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  8. 	<META NAME="CHANGEDBY" CONTENT="Anatoli Arkhipenko">
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  25. <BODY LANG="en-US" TEXT="#000000" LINK="#0000ff" BGCOLOR="#ffffff" DIR="LTR">
    26. 

  26. <P CLASS="western" STYLE="margin-bottom: 0in"><FONT SIZE=4 STYLE="font-size: 15pt"><B>Task
    27. 

  27. Scheduler</B></FONT></P>
    28. 

  28. <P CLASS="western" STYLE="margin-bottom: 0in"><B>Cooperative
    29. 

  29. multitasking for Arduino microcontrollers</B></P>
    30. 

  30. <P CLASS="western" STYLE="margin-bottom: 0in; border-top: none; border-bottom: 1px solid #000000; border-left: none; border-right: none; padding-top: 0in; padding-bottom: 0.01in; padding-left: 0in; padding-right: 0in">
    31. 

  31. <FONT SIZE=2 STYLE="font-size: 11pt"><B>Version 2.0.0: 2015-12-23</B></FONT></P>
    32. 

  32. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    33. 

  33. </P>
    34. 

  34. <P CLASS="western" STYLE="margin-bottom: 0in"><B>OVERVIEW</B>:</P>
    35. 

  35. <P CLASS="western" STYLE="margin-bottom: 0in">A lightweight
    36. 

  36. implementation of cooperative multitasking (task scheduling)
    37. 

  37. supporting:</P>
    38. 

  38. <OL>
    39. 

  39. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in">Periodic task
    40. 

  40. 	execution (with dynamic execution period in milliseconds –
    41. 

  41. 	frequency of execution)</P>
    42. 

  42. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in">Number of
    43. 

  43. 	iterations (limited or infinite number of iterations)</P>
    44. 

  44. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in">Execution of tasks
    45. 

  45. 	in predefined sequence</P>
    46. 

  46. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in">Dynamic change of
    47. 

  47. 	task execution parameters (frequency, number of iterations, callback
    48. 

  48. 	methods)</P>
    49. 

  49. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in">Power saving via
    50. 

  50. 	entering IDLE sleep mode when tasks are not scheduled to run</P>
    51. 

  51. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in">Support for
    52. 

  52. 	event-driven task invocation via Status Request object</P>
    53. 

  53. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in">Support for task
    54. 

  54. 	IDs and Control Points for error handling and watchdog timer</P>
    55. 

  55. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in">Support for Local
    56. 

  56. 	Task Storage pointer (allowing use of same callback code for
    57. 

  57. 	multiple tasks)</P>
    58. 

  58. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in">Support for
    59. 

  59. 	layered task prioritization</P>
    60. 

  60. </OL>
    61. 

  61. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    62. 

  62. </P>
    63. 

  63. <P CLASS="western" STYLE="margin-bottom: 0in">Scheduling overhead:
    64. 

  64. between 15 and 18 microseconds per scheduling pass.</P>
    65. 

  65. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    66. 

  66. </P>
    67. 

  67. <P CLASS="western" STYLE="margin-bottom: 0in"><B>TASK</B>:</P>
    68. 

  68. <P CLASS="western" STYLE="margin-bottom: 0in">“Task” is a
    69. 

  69. container concept that links together:</P>
    70. 

  70. <OL>
    71. 

  71. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in">Program code
    72. 

  72. 	performing specific task activities (callback methods)</P>
    73. 

  73. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in">Execution interval</P>
    74. 

  74. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in">Number of
    75. 

  75. 	execution iterations</P>
    76. 

  76. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in">(Optionally)
    77. 

  77. 	Execution event (Status Request)</P>
    78. 

  78. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in">(Optionally)
    79. 

  79. 	Pointer to a Local Task Storage area</P>
    80. 

  80. </OL>
    81. 

  81. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    82. 

  82. </P>
    83. 

  83. <P CLASS="western" STYLE="margin-bottom: 0in"><B>Tasks</B> perform
    84. 

  84. certain functions, which could require periodic or one-time
    85. 

  85. execution, update of specific variables, or waiting for specific
    86. 

  86. events. Tasks also could be controlling specific hardware, or
    87. 

  87. triggered by hardware interrupts. 
    88. 

  88. </P>
    89. 

  89. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    90. 

  90. </P>
    91. 

  91. <P CLASS="western" STYLE="margin-bottom: 0in">For execution purposes
    92. 

  92. <B>Tasks</B> are linked into execution <B>chains</B>, which are
    93. 

  93. processed by the <B>Scheduler</B> in the order they were added
    94. 

  94. (linked together).</P>
    95. 

  95. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    96. 

  96. </P>
    97. 

  97. <P CLASS="western" STYLE="margin-bottom: 0in"><B>Starting with
    98. 

  98. version 2.0.0 TaskScheduler supports task prioritization. Please
    99. 

  99. refer to the specific chapter of this manual for details on layered
    100. 

  100. prioritization. </B>
    101. 

  101. </P>
    102. 

  102. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    103. 

  103. </P>
    104. 

  104. <P CLASS="western" STYLE="margin-bottom: 0in">Each task performs its
    105. 

  105. function via a callback method. Scheduler calls Task’s callback
    106. 

  106. method periodically until task is disabled or runs out of iterations.
    107. 

  107. In addition to “regular” callback method, two additional methods
    108. 

  108. could be utilized for each task: a callback method invoked every time
    109. 

  109. the task is enabled, and a callback method invoked once when the task
    110. 

  110. is disabled. Those two special methods allow tasks to properly
    111. 

  111. initiate themselves for execution, and clean-up after execution is
    112. 

  112. over (E.g., setup pin modes on enable, and always bring pin level to
    113. 

  113. LOW at the end). 
    114. 

  114. </P>
    115. 

  115. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    116. 

  116. </P>
    117. 

  117. <P CLASS="western" STYLE="margin-bottom: 0in">Tasks are responsible
    118. 

  118. for supporting <B>cooperative</B> <B>multitasking</B> by being “good
    119. 

  119. neighbors”, i.e., running their callback methods quickly in a
    120. 

  120. non-blocking way, and releasing control back to scheduler as soon as
    121. 

  121. possible. 
    122. 

  122. </P>
    123. 

  123. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    124. 

  124. </P>
    125. 

  125. <P CLASS="western" STYLE="margin-bottom: 0in"><B>Scheduler</B> is
    126. 

  126. executing Tasks' callback methods in the order the tasks were added
    127. 

  127. to the chain, from first to last. Scheduler stops and exists after
    128. 

  128. processing the chain once in order to allow other statements in the
    129. 

  129. main code of <B>loop()</B> method to run.  This is referred to as a
    130. 

  130. <B>“scheduling pass”.</B></P>
    131. 

  131. <P CLASS="western" STYLE="margin-bottom: 0in">(Normally, there is no
    132. 

  132. need to have any other statements in the <B>loop</B>() method other
    133. 

  133. than the Scheduler's <B>execute</B>() method).</P>
    134. 

  134. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    135. 

  135. </P>
    136. 

  136. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    137. 

  137. <B>Below is the flowchart of a Task lifecycle:</B></P>
    138. 

  138. <P CLASS="western" STYLE="margin-bottom: 0in"><IMG SRC="TaskScheduler_html.png" NAME="graphics1" ALIGN=BOTTOM WIDTH=664 HEIGHT=517 BORDER=0></P>
    139. 

  139. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    140. 

  140. </P>
    141. 

  141. <P CLASS="western" STYLE="margin-bottom: 0in"><B>TaskScheduler</B>
    142. 

  142. library maybe compiled with different compilation controls
    143. 

  143. enabled/disabled. This is a way to limit TaskScheduler functionality
    144. 

  144. (and size) for specific purpose (sketch). This is achieved by
    145. 

  145. defining specific #<B>define</B> parameters <I>before</I>
    146. 

  146. TaskScheduler.h header file. Specifically:</P>
    147. 

  147. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    148. 

  148. </P>
    149. 

  149. <P CLASS="western" STYLE="margin-bottom: 0in">If compiled with
    150. 

  150. <FONT FACE="Courier New, monospace">_TASK_SLEEP_ON_IDLE_RUN</FONT>
    151. 

  151. enabled, the scheduler will place processor into IDLE sleep mode (for
    152. 

  152. approximately 1 ms, as the timer interrupt will wake it up), after
    153. 

  153. what is determined to be an “idle” pass. An Idle Pass is a pass
    154. 

  154. through the task chain when no Tasks were scheduled to run their
    155. 

  155. callback methods. This is done to avoid repetitive idle passes
    156. 

  156. through the chain when no tasks need to be executed. If any of the
    157. 

  157. tasks in the chain always requires immediate execution (aInterval =
    158. 

  158. 0), then there will be no IDLE sleep between task's callback method
    159. 

  159. execution.</P>
    160. 

  160. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    161. 

  161. </P>
    162. 

  162. <P CLASS="western" STYLE="margin-bottom: 0in"><B>NOTE: </B>Task
    163. 

  163. Scheduler uses <B>millis()</B> to determine if tasks are ready to be
    164. 

  164. invoked. Therefore, if you put your device to any “deep” sleep
    165. 

  165. mode disabling timer interrupts, the <B>millis()</B> count will be
    166. 

  166. suspended, leading to effective suspension of scheduling. Upon wake
    167. 

  167. up, active tasks need to be re-enabled, which will effectively reset
    168. 

  168. their internal time scheduling variables to the new value of
    169. 

  169. <B>millis(). </B>Time spent in deep sleep mode should be considered
    170. 

  170. “frozen”, i.e., if a task was scheduled to run in 1 second from
    171. 

  171. now, and device was put to sleep for 5 minutes, upon wake up, the
    172. 

  172. task will still be scheduled 1 second from the time of wake up.
    173. 

  173. Executing <B>enable() </B>method on this tasks will make it run as
    174. 

  174. soon as possible. This is a concern only for tasks which are required
    175. 

  175. to run in a truly periodical manner (in absolute time terms). 
    176. 

  176. </P>
    177. 

  177. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    178. 

  178. </P>
    179. 

  179. <P CLASS="western" STYLE="margin-bottom: 0in">In addition to
    180. 

  180. time-only (<B>millis</B>() only)  invocation, tasks can be scheduled
    181. 

  181. to wait on an event employing StatusRequest objects (more about
    182. 

  182. Status Requests later).</P>
    183. 

  183. <P CLASS="western" STYLE="margin-bottom: 0in">Consider a scenario
    184. 

  184. when one task (t1) is performing a function which affects execution
    185. 

  185. of many tasks (t2, t3). In this case the task t1 will “signal”
    186. 

  186. completion of its function via Status Request object. Tasks t2 and t3
    187. 

  187. are “waiting” on the same Status Request object. As soon as
    188. 

  188. status request completes, t2 and t3 are activated.</P>
    189. 

  189. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    190. 

  190. </P>
    191. 

  191. <P CLASS="western" STYLE="margin-bottom: 0in">Alternative scenario is
    192. 

  192. the ne task (t1) and waiting for the completion of a number of tasks
    193. 

  193. (t2, t3). When done, t2 and t3 signal completion of their functions,
    194. 

  194. t1 is invoked. 
    195. 

  195. </P>
    196. 

  196. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    197. 

  197. </P>
    198. 

  198. <P CLASS="western" STYLE="margin-bottom: 0in">Please see the code
    199. 

  199. examples at the end of this document, and included with the library
    200. 

  200. package for details.</P>
    201. 

  201. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    202. 

  202. </P>
    203. 

  203. <P CLASS="western" STYLE="margin-bottom: 0in"><B>COMPILE PARAMETERS:</B></P>
    204. 

  204. <P CLASS="western" STYLE="margin-bottom: 0in">This library could be
    205. 

  205. compiled in several configurations.</P>
    206. 

  206. <P CLASS="western" STYLE="margin-bottom: 0in">Parameters (<B>#define</B>s)
    207. 

  207. defining what functionality should or should not be included need be
    208. 

  208. defined before the library header file in the body of arduino sketch.</P>
    209. 

  209. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    210. 

  210. </P>
    211. 

  211. <P CLASS="western" STYLE="margin-bottom: 0in">#define
    212. 

  212. <B>_TASK_TIMECRITICAL</B></P>
    213. 

  213. <P CLASS="western" STYLE="margin-bottom: 0in">...will compile the
    214. 

  214. library with time critical tracking option enabled.</P>
    215. 

  215. <P CLASS="western" STYLE="margin-bottom: 0in">Time critical option
    216. 

  216. keeps track when current execution took place relative to when it was
    217. 

  217. scheduled, and where next execution time of the task falls. Two
    218. 

  218. methods provide this information. 
    219. 

  219. </P>
    220. 

  220. <P CLASS="western" STYLE="margin-bottom: 0in"><B>Task::getStartDelay()
    221. 

  221. </B>method: return number of milliseconds between current system time
    222. 

  222. (millis) and point in time when the task was scheduled to start. A
    223. 

  223. value of 0 (zero) indicates that task started right on time per
    224. 

  224. schedule. 
    225. 

  225. </P>
    226. 

  226. <P CLASS="western" STYLE="margin-bottom: 0in"><B>Task::getOverrun()</B>
    227. 

  227. method: If <B>getOverrun </B>returns a negative value, this Task’s
    228. 

  228. next execution time point is <I>already</I> in the past, and task is
    229. 

  229. behind schedule. This most probably means that either task’s
    230. 

  230. callback method's runtime is too long, or the execution interval is
    231. 

  231. too short (and therefore schedule is too aggressive).</P>
    232. 

  232. <P CLASS="western" STYLE="margin-bottom: 0in">A positive value
    233. 

  233. indicates that task is on schedule, and callback methods have enough
    234. 

  234. time to finish before the next scheduled pass. 
    235. 

  235. </P>
    236. 

  236. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    237. 

  237. </P>
    238. 

  238. <P CLASS="western" STYLE="margin-bottom: 0in">#define
    239. 

  239. <B>_TASK_SLEEP_ON_IDLE_RUN</B></P>
    240. 

  240. <P CLASS="western" STYLE="margin-bottom: 0in">...will compile the
    241. 

  241. library with the <B>sleep</B> option enabled (AVR boards only).</P>
    242. 

  242. <P CLASS="western" STYLE="margin-bottom: 0in">When enabled, scheduler
    243. 

  243. will put the microcontroller into <B>SLEEP_MODE_IDLE</B> state if
    244. 

  244. none of the tasks’ callback methods were activated during execution
    245. 

  245. pass. <B>IDLE</B> state is interrupted by timers once every 1 ms.
    246. 

  246. Putting microcontroller to IDLE state helps conserve power.  Device
    247. 

  247. in SLEEP_MODE_IDLE wakes up to all hardware and timer interrupts, so
    248. 

  248. scheduling is kept current.</P>
    249. 

  249. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    250. 

  250. </P>
    251. 

  251. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    252. 

  252. #define <B>_TASK_STATUS_REQUEST</B></P>
    253. 

  253. <P CLASS="western" STYLE="margin-bottom: 0in">…will compile
    254. 

  254. TaskScheduler with support for StatusRequest object. Status Requests
    255. 

  255. are objects allowing tasks to wait on an event, and signal event
    256. 

  256. completion to each other. 
    257. 

  257. </P>
    258. 

  258. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    259. 

  259. </P>
    260. 

  260. <P CLASS="western" STYLE="margin-bottom: 0in">#define <B>_TASK_WDT_IDS</B></P>
    261. 

  261. <P CLASS="western" STYLE="margin-bottom: 0in">…will compile
    262. 

  262. TaskScheduler with support for Task IDs and Control Points. Each task
    263. 

  263. can be (and is by default) assigned an ID, which could be used to
    264. 

  264. identify the task in case there is a problem with it. Furthermore
    265. 

  265. within the task, Control Points could be defined to further help with
    266. 

  266. pinpointing potential problem areas. For instance, the tasks which
    267. 

  267. deal with external resources (sensors, serial communications,
    268. 

  268. anything hardware dependent) can be blocked (or hung), by failed
    269. 

  269. hardware. In this case, a watchdog timer could be employed to trap
    270. 

  270. such a failed task, and identify which one (by task id) and where in
    271. 

  271. the task (by a control point) the problem is likely located.</P>
    272. 

  272. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    273. 

  273. </P>
    274. 

  274. <P CLASS="western" STYLE="margin-bottom: 0in"><B>NOTE: </B>by
    275. 

  275. default, talk IDs are assigned sequentially (1, 2, 3, …) to the
    276. 

  276. tasks as they are being created. Programmer can assign a specific
    277. 

  277. task id. <B>Task ids are unsigned integers.</B></P>
    278. 

  278. <P CLASS="western" STYLE="margin-bottom: 0in">Control points provide
    279. 

  279. a way to identify potential problem points within a task. Control
    280. 

  280. points are <B>unsigned integers </B>as well. Please note that there
    281. 

  281. is only one control point per task, and it is set to zero when the
    282. 

  282. task’s callback method is invoked (this is done to prevent “stray”
    283. 

  283. control point from previous task(s) confusing the matters.</P>
    284. 

  284. <P CLASS="western" STYLE="margin-bottom: 0in">Example #7 contains a
    285. 

  285. test of task ID and control points functionality.  
    286. 

  286. </P>
    287. 

  287. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    288. 

  288. </P>
    289. 

  289. <P CLASS="western" STYLE="margin-bottom: 0in">#define
    290. 

  290. <B>_TASK_LTS_POINTER</B></P>
    291. 

  291. <P CLASS="western" STYLE="margin-bottom: 0in">…will compile
    292. 

  292. TaskScheduler with support for Local Task Storage pointer (LTS). LTS
    293. 

  293. is a generic (void*) pointer which could be set to reference a
    294. 

  294. variable or a structure specific to a particular task. A callback
    295. 

  295. method can get access to specific variables by getting reference to a
    296. 

  296. currently running task from the scheduler, and then casting (void*)
    297. 

  297. LTS pointer to the appropriate pointer type. 
    298. 

  298. </P>
    299. 

  299. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    300. 

  300. </P>
    301. 

  301. <P CLASS="western" STYLE="margin-bottom: 0in"><B>NOTE: </B>above
    302. 

  302. parameters are<B> DISABLED </B>by default, and need to be explicitly
    303. 

  303. enabled by placing appropriate #define statements in front of the
    304. 

  304. #include statement for the TaskScheduler header file.</P>
    305. 

  305. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    306. 

  306. </P>
    307. 

  307. <P CLASS="western" STYLE="margin-bottom: 0in">#define <B>_TASK_PRIORITY</B></P>
    308. 

  308. <P CLASS="western" STYLE="margin-bottom: 0in">…will compile
    309. 

  309. TaskScheduler with support for layered task prioritization. Task
    310. 

  310. prioritization is achieved by creating several schedulers, and
    311. 

  311. organizing them in priority layers. Tasks are assigned to schedulers
    312. 

  312. corresponding to their priority. Tasks assigned to the “higher”
    313. 

  313. layers are evaluated for invocation more frequently, and are given
    314. 

  314. priority in execution in case of the scheduling coincidence. More
    315. 

  315. about layered prioritization in the API documentation and
    316. 

  316. TaskScheduler examples.  
    317. 

  317. </P>
    318. 

  318. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    319. 

  319. </P>
    320. 

  320. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    321. 

  321. </P>
    322. 

  322. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    323. 

  323. </P>
    324. 

  324. <P CLASS="western" STYLE="margin-bottom: 0in"><B>TASK PRIORITY AND
    325. 

  325. COOPERATIVE MULTITASKING:</B></P>
    326. 

  326. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    327. 

  327. </P>
    328. 

  328. <P CLASS="western" STYLE="margin-bottom: 0in">Starting with version
    329. 

  329. 2.0.0 TaskScheduler supports task prioritization. Priority is
    330. 

  330. associated with a <B>Scheduler</B>, not individual <B>Tasks</B>,
    331. 

  331. hence the concept of priority layers. Tasks subsequently are assigned
    332. 

  332. to schedulers corresponding to their desired priority. The lowest
    333. 

  333. priority Scheduler is called “<B>base scheduler</B>” or “<B>base
    334. 

  334. layer</B>”. Let’s call higher priority schedulers by their
    335. 

  335. priority number, with larger number corresponding to higher priority
    336. 

  336. of task execution. 
    337. 

  337. </P>
    338. 

  338. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    339. 

  339. </P>
    340. 

  340. <P CLASS="western" STYLE="margin-bottom: 0in">Task prioritization is
    341. 

  341. achieved by executing the entire chain of tasks of the higher
    342. 

  342. priority scheduler for every single step (task) of the lower priority
    343. 

  343. chain. <B>Note</B> that actual callback method invocation depends on
    344. 

  344. priority <B>and </B>the timing of task schedule. However, higher
    345. 

  345. priority tasks are evaluated more frequently and are given priority
    346. 

  346. in case of scheduling collision. 
    347. 

  347. </P>
    348. 

  348. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    349. 

  349. </P>
    350. 

  350. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    351. 

  351. </P>
    352. 

  352. <P CLASS="western" STYLE="margin-bottom: 0in">For most tasks
    353. 

  353. TaskScheduler <B>does not need </B>task priority functionality.
    354. 

  354. Prioritization requires additional scheduling overhead, and should be
    355. 

  355. used only for critical tasks.</P>
    356. 

  356. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    357. 

  357. </P>
    358. 

  358. <P CLASS="western" STYLE="margin-bottom: 0in">A few points on that:</P>
    359. 

  359. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    360. 

  360. </P>
    361. 

  361. <P CLASS="western" STYLE="margin-bottom: 0in">1. Plain (non-layered)
    362. 

  362. execution chain is simple and efficient. The main idea is to minimize
    363. 

  363. scheduling overhead by Scheduler going through the chain. Each
    364. 

  364. priority layer adds scheduling overhead to overall task chain
    365. 

  365. execution. Let’s review 3 scenarios:</P>
    366. 

  366. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    367. 

  367. </P>
    368. 

  368. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><B>I.
    369. 

  369. Flat chain of 7 tasks:</B></P>
    370. 

  370. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Scheduling
    371. 

  371. evaluation sequence:</P>
    372. 

  372. <P CLASS="western" ALIGN=CENTER STYLE="margin-left: 0.49in; margin-bottom: 0in">
    373. 

  373. 1 <FONT FACE="Wingdings"></FONT> 2 <FONT FACE="Wingdings"></FONT>
    374. 

  374. 3 <FONT FACE="Wingdings"></FONT> 4 <FONT FACE="Wingdings"></FONT>
    375. 

  375. 5 <FONT FACE="Wingdings"></FONT> 6 <FONT FACE="Wingdings"></FONT>
    376. 

  376. 7</P>
    377. 

  377. <P CLASS="western" ALIGN=CENTER STYLE="margin-left: 0.49in; margin-bottom: 0in">
    378. 

  378. <BR>
    379. 

  379. </P>
    380. 

  380. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Scheduling
    381. 

  381. overhead:</P>
    382. 

  382. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">O
    383. 

  383. = B * T = 7 * 18 = 126 microseconds,</P>
    384. 

  384. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Where:</P>
    385. 

  385. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in">O
    386. 

  386. – scheduling overhead</P>
    387. 

  387. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in">B
    388. 

  388. – number of tasks in the base layer</P>
    389. 

  389. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in">T
    390. 

  390. – scheduling overhead of a single task execution evaluation
    391. 

  391. (currently with Arduino Uno running at 16 Mhz is between 15 and 18
    392. 

  392. microseconds).</P>
    393. 

  393. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    394. 

  394. </P>
    395. 

  395. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><B>II.
    396. 

  396. Two priority layers of 7 tasks. </B>
    397. 

  397. </P>
    398. 

  398. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><B>	</B>Tasks
    399. 

  399. 1, 2, 3, 4, 5 are base priority and 6, 7 are higher priority:</P>
    400. 

  400. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    401. 

  401. </P>
    402. 

  402. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Scheduling
    403. 

  403. evaluation sequence:</P>
    404. 

  404. <P CLASS="western" ALIGN=CENTER STYLE="margin-left: 0.49in; margin-bottom: 0in">
    405. 

  405. 6 <FONT FACE="Wingdings"></FONT> 7 <FONT FACE="Wingdings"></FONT>
    406. 

  406. 1 <FONT FACE="Wingdings"></FONT> 6 <FONT FACE="Wingdings"></FONT>
    407. 

  407. 7 <FONT FACE="Wingdings"></FONT> 2 <FONT FACE="Wingdings"></FONT>
    408. 

  408. 6 <FONT FACE="Wingdings"></FONT> 7 <FONT FACE="Wingdings"></FONT>
    409. 

  409. 3 <FONT FACE="Wingdings"></FONT> 6 <FONT FACE="Wingdings"></FONT>
    410. 

  410. 7 <FONT FACE="Wingdings"></FONT> 4 <FONT FACE="Wingdings"></FONT>
    411. 

  411. 6 <FONT FACE="Wingdings"></FONT> 7 <FONT FACE="Wingdings"></FONT>
    412. 

  412. 5</P>
    413. 

  413. <P CLASS="western" ALIGN=CENTER STYLE="margin-left: 0.49in; margin-bottom: 0in">
    414. 

  414. <BR>
    415. 

  415. </P>
    416. 

  416. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Scheduling
    417. 

  417. overhead:</P>
    418. 

  418. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">O
    419. 

  419. = (B + B * P1) * T = (5 + 5 * 2) * 18 = 270 microseconds,</P>
    420. 

  420. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Where:</P>
    421. 

  421. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in">O
    422. 

  422. – scheduling overhead</P>
    423. 

  423. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in">B
    424. 

  424. – number of tasks in the base layer</P>
    425. 

  425. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in">P1
    426. 

  426. – number of tasks in the priority 1 layer</P>
    427. 

  427. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in">T
    428. 

  428. – scheduling overhead of a single task execution evaluation
    429. 

  429. (currently with Arduino Uno running at 16 Mhz is between 15 and 18
    430. 

  430. microseconds).</P>
    431. 

  431. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    432. 

  432. </P>
    433. 

  433. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><B>III.
    434. 

  434. Three priority layers of 7 tasks. </B>
    435. 

  435. </P>
    436. 

  436. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><B>	</B>Tasks
    437. 

  437. 1, 2, 3, are base priority, 4, 5 are priority 1, and 6, 7 are
    438. 

  438. priority 2:</P>
    439. 

  439. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    440. 

  440. </P>
    441. 

  441. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Scheduling
    442. 

  442. evaluation sequence:</P>
    443. 

  443. <P CLASS="western" ALIGN=CENTER STYLE="margin-left: 0.49in; margin-bottom: 0in">
    444. 

  444. 6 <FONT FACE="Wingdings"></FONT> 7 <FONT FACE="Wingdings"></FONT>
    445. 

  445. 4 <FONT FACE="Wingdings"></FONT> 6 <FONT FACE="Wingdings"></FONT>
    446. 

  446. 7 <FONT FACE="Wingdings"></FONT> 5 <FONT FACE="Wingdings"></FONT>
    447. 

  447. 1 <FONT FACE="Wingdings"></FONT> 6 <FONT FACE="Wingdings"></FONT>
    448. 

  448. 7 <FONT FACE="Wingdings"></FONT> 4 <FONT FACE="Wingdings"></FONT>
    449. 

  449. 6 <FONT FACE="Wingdings"></FONT> 7 <FONT FACE="Wingdings"></FONT>
    450. 

  450. 5 <FONT FACE="Wingdings"></FONT> 2 <FONT FACE="Wingdings"></FONT>6
    451. 

  451. <FONT FACE="Wingdings"></FONT> 7 <FONT FACE="Wingdings"></FONT>
    452. 

  452. 4 <FONT FACE="Wingdings"></FONT> 6 <FONT FACE="Wingdings"></FONT>
    453. 

  453. 7 <FONT FACE="Wingdings"></FONT> 5 <FONT FACE="Wingdings"></FONT>
    454. 

  454. 3 
    455. 

  455. </P>
    456. 

  456. <P CLASS="western" ALIGN=CENTER STYLE="margin-left: 0.49in; margin-bottom: 0in">
    457. 

  457. <BR>
    458. 

  458. </P>
    459. 

  459. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Scheduling
    460. 

  460. overhead:</P>
    461. 

  461. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">O
    462. 

  462. = (B + B * P1 + B * P1 * P2) * T = (3 + 3 * 2 + 3 * 2 * 2) * 18 = 378
    463. 

  463. microseconds,</P>
    464. 

  464. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Where:</P>
    465. 

  465. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in">O
    466. 

  466. – scheduling overhead</P>
    467. 

  467. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in">B
    468. 

  468. – number of tasks in the base layer</P>
    469. 

  469. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in">P1
    470. 

  470. – number of tasks in the priority 1 layer</P>
    471. 

  471. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in">P2
    472. 

  472. – number of tasks in the priority 2 layer</P>
    473. 

  473. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in">T
    474. 

  474. – scheduling overhead of a single task execution evaluation
    475. 

  475. (currently with Arduino Uno running at 16 Mhz is between 15 and 18
    476. 

  476. microseconds).</P>
    477. 

  477. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    478. 

  478. </P>
    479. 

  479. <P CLASS="western" STYLE="margin-bottom: 0in">Scheduling overhead of
    480. 

  480. a 3 layer prioritization approach is 3 times higher than that of a
    481. 

  481. flat execution chain. <B>Do</B> evaluate if task prioritization is
    482. 

  482. really required for your sketch.</P>
    483. 

  483. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    484. 

  484. </P>
    485. 

  485. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    486. 

  486. </P>
    487. 

  487. <P CLASS="western" STYLE="margin-bottom: 0in">2. TaskScheduler is <B>NOT</B>
    488. 

  488. a pre-emptive multi-tasking library. Nor is it a Real-Time OS. There
    489. 

  489. is no way to break execution of one task in favor of another.
    490. 

  490. Therefore callback methods require careful programming for
    491. 

  491. cooperative behavior.</P>
    492. 

  492. <P CLASS="western" STYLE="margin-bottom: 0in">This has, however,
    493. 

  493. significant benefits: you don't need to worry about concurrency
    494. 

  494. inside the callback method, since only one callback method runs at a
    495. 

  495. time, and could not be interrupted. All resources are yours for that
    496. 

  496. period of time, no one can switch the value of variables (except
    497. 

  497. interrupt functions of course...), etc. It is a stable and
    498. 

  498. predictable environment, and it helps a lot with writing stable code.
    499. 

  499. </P>
    500. 

  500. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    501. 

  501. </P>
    502. 

  502. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    503. 

  503. </P>
    504. 

  504. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    505. 

  505. </P>
    506. 

  506. <P CLASS="western" STYLE="margin-bottom: 0in">A number of things
    507. 

  507. could be done instead of priorities:</P>
    508. 

  508. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    509. 

  509. </P>
    510. 

  510. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    511. 

  511. </P>
    512. 

  512. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    513. 

  513. </P>
    514. 

  514. <P CLASS="western" STYLE="margin-bottom: 0in">1. Schedule your
    515. 

  515. critical tasks to run more frequently than the other tasks</P>
    516. 

  516. <P CLASS="western" STYLE="margin-bottom: 0in">. <BR>(Since you can
    517. 

  517. control the interval, you could also change the task to run more or
    518. 

  518. less frequently as the situation demands).</P>
    519. 

  519. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    520. 

  520. </P>
    521. 

  521. <P CLASS="western" STYLE="margin-bottom: 0in">2. If one particular
    522. 

  522. callback routine is critical, create a couple of tasks referring to
    523. 

  523. the same callback and &quot;sprinkle&quot; them around the chain:</P>
    524. 

  524. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    525. 

  525. </P>
    526. 

  526. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    527. 

  527. </P>
    528. 

  528. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    529. 

  529. </P>
    530. 

  530. <P CLASS="western" STYLE="margin-bottom: 0in">    <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">Scheduler
    531. 

  531. ts;</FONT></FONT></P>
    532. 

  532. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    533. 

  533. </P>
    534. 

  534. <P CLASS="western" STYLE="margin-bottom: 0in">    <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">Task
    535. 

  535. t1(20, TASK_FOREVER, &amp;callback1, &amp;ts);</FONT></FONT></P>
    536. 

  536. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    537. 

  537. </P>
    538. 

  538. <P CLASS="western" STYLE="margin-bottom: 0in">    <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">Task
    539. 

  539. t2(1000, TASK_FOREVER, &amp;callback2, &amp;ts);</FONT></FONT></P>
    540. 

  540. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    541. 

  541. </P>
    542. 

  542. <P CLASS="western" STYLE="margin-bottom: 0in">    <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">Task
    543. 

  543. t3(20, TASK_FOREVER, &amp;callback1, &amp;ts);</FONT></FONT></P>
    544. 

  544. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    545. 

  545. </P>
    546. 

  546. <P CLASS="western" STYLE="margin-bottom: 0in">    <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">Task
    547. 

  547. t4(1000, TASK_FOREVER, &amp;callback4, &amp;ts);</FONT></FONT></P>
    548. 

  548. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    549. 

  549. </P>
    550. 

  550. <P CLASS="western" STYLE="margin-bottom: 0in">    <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">t3.delay(10);</FONT></FONT></P>
    551. 

  551. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    552. 

  552. </P>
    553. 

  553. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    554. 

  554. </P>
    555. 

  555. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    556. 

  556. </P>
    557. 

  557. <P CLASS="western" STYLE="margin-bottom: 0in">Note that t1 and t3
    558. 

  558. call the same callback method, and are shifted in time by 10 millis.
    559. 

  559. So effectively callback1 will be called every 10 millis, but would be
    560. 

  560. &quot;sandwiched&quot; between t2 and t4. 
    561. 

  561. </P>
    562. 

  562. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    563. 

  563. </P>
    564. 

  564. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    565. 

  565. </P>
    566. 

  566. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    567. 

  567. </P>
    568. 

  568. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    569. 

  569. </P>
    570. 

  570. <P CLASS="western" STYLE="margin-bottom: 0in">3. Use short efficient
    571. 

  571. callback methods written for cooperative multitasking.</P>
    572. 

  572. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    573. 

  573. </P>
    574. 

  574. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    575. 

  575. </P>
    576. 

  576. <P CLASS="western" STYLE="margin-bottom: 0in">What that means is:</P>
    577. 

  577. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    578. 

  578. </P>
    579. 

  579. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    580. 

  580. </P>
    581. 

  581. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    582. 

  582. </P>
    583. 

  583. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">a)
    584. 

  584. <B>DO NOT</B> use Arduino's  <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt"><B>delay</B></FONT></FONT><FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">()</FONT></FONT><FONT FACE="Andale Mono, MS Mincho">
    585. 

  585. </FONT>function. It is blocking and will hold the entire chain.
    586. 

  586. Instead break the callback method into two, switch the callback
    587. 

  587. method of the task where delay is necessary and delay the task by
    588. 

  588. that number of millis. You get your delay, and other tasks get a
    589. 

  589. chance to run:</P>
    590. 

  590. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    591. 

  591. </P>
    592. 

  592. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    593. 

  593. </P>
    594. 

  594. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    595. 

  595. </P>
    596. 

  596. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">instead
    597. 

  597. of:</P>
    598. 

  598. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    599. 

  599. </P>
    600. 

  600. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    601. 

  601. </P>
    602. 

  602. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    603. 

  603. </P>
    604. 

  604. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    605. 

  605.  <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">void
    606. 

  606. callback() {</FONT></FONT></P>
    607. 

  607. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    608. 

  608. </P>
    609. 

  609. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    610. 

  610.   <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">...
    611. 

  611. stuff</FONT></FONT></P>
    612. 

  612. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    613. 

  613. </P>
    614. 

  614. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    615. 

  615.   <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">delay(1000);</FONT></FONT></P>
    616. 

  616. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    617. 

  617. </P>
    618. 

  618. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    619. 

  619.   <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">...
    620. 

  620. more stuff</FONT></FONT></P>
    621. 

  621. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    622. 

  622. </P>
    623. 

  623. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    624. 

  624.  <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">}</FONT></FONT></P>
    625. 

  625. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    626. 

  626. </P>
    627. 

  627. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    628. 

  628.   
    629. 

  629. </P>
    630. 

  630. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    631. 

  631. </P>
    632. 

  632. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">do
    633. 

  633. this:</P>
    634. 

  634. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    635. 

  635. </P>
    636. 

  636. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    637. 

  637. </P>
    638. 

  638. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    639. 

  639. </P>
    640. 

  640. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    641. 

  641.  <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">void
    642. 

  642. callback1() {</FONT></FONT></P>
    643. 

  643. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    644. 

  644. </P>
    645. 

  645. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    646. 

  646.   <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">...
    647. 

  647. stuff</FONT></FONT></P>
    648. 

  648. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    649. 

  649. </P>
    650. 

  650. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    651. 

  651.   <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">t1.setCallback(&amp;callback2);</FONT></FONT></P>
    652. 

  652. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    653. 

  653. </P>
    654. 

  654. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    655. 

  655.   <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">t1.delay(1000);</FONT></FONT></P>
    656. 

  656. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    657. 

  657. </P>
    658. 

  658. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    659. 

  659.  <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">}</FONT></FONT></P>
    660. 

  660. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    661. 

  661. </P>
    662. 

  662. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    663. 

  663. </P>
    664. 

  664. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    665. 

  665.  <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">void
    666. 

  666. callback2() {</FONT></FONT></P>
    667. 

  667. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    668. 

  668. </P>
    669. 

  669. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    670. 

  670.   <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">...
    671. 

  671. more stuff</FONT></FONT></P>
    672. 

  672. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    673. 

  673. </P>
    674. 

  674. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    675. 

  675.   <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">t1.setCallback(&amp;callback1);</FONT></FONT></P>
    676. 

  676. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    677. 

  677. </P>
    678. 

  678. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    679. 

  679.  <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">}</FONT></FONT></P>
    680. 

  680. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    681. 

  681. </P>
    682. 

  682. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    683. 

  683. </P>
    684. 

  684. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    685. 

  685. </P>
    686. 

  686. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    687. 

  687. </P>
    688. 

  688. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    689. 

  689. </P>
    690. 

  690. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">b)
    691. 

  691. Same goes to <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt"><B>pulseIn</B></FONT></FONT><FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">()</FONT></FONT>
    692. 

  692. function. If you have to use it, set the timeout parameter such that
    693. 

  693. it is not a default 1 second. PulseIn functionality could be achieved
    694. 

  694. via pin interrupts, and that solution is non-blocking.</P>
    695. 

  695. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    696. 

  696. </P>
    697. 

  697. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    698. 

  698. </P>
    699. 

  699. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    700. 

  700. </P>
    701. 

  701. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">c)
    702. 

  702. Do don run long loops (for or do/while) in you callback methods. Make
    703. 

  703. the main arduino loop be the loop driver for you:</P>
    704. 

  704. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    705. 

  705. </P>
    706. 

  706. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    707. 

  707. </P>
    708. 

  708. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    709. 

  709. </P>
    710. 

  710. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">instead
    711. 

  711. of:</P>
    712. 

  712. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    713. 

  713. </P>
    714. 

  714. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    715. 

  715. </P>
    716. 

  716. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    717. 

  717. </P>
    718. 

  718. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    719. 

  719.  <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">void
    720. 

  720. callback() {</FONT></FONT></P>
    721. 

  721. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    722. 

  722. </P>
    723. 

  723. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    724. 

  724.  
    725. 

  725. </P>
    726. 

  726. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    727. 

  727. </P>
    728. 

  728. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    729. 

  729.    <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">for(int
    730. 

  730. i=0; i&lt;1000; i++) {</FONT></FONT></P>
    731. 

  731. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    732. 

  732. </P>
    733. 

  733. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    734. 

  734.      <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">...
    735. 

  735. stuff // one loop action</FONT></FONT></P>
    736. 

  736. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    737. 

  737. </P>
    738. 

  738. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    739. 

  739.    <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">}</FONT></FONT></P>
    740. 

  740. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    741. 

  741. </P>
    742. 

  742. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    743. 

  743.  <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">}</FONT></FONT></P>
    744. 

  744. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    745. 

  745. </P>
    746. 

  746. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    747. 

  747. </P>
    748. 

  748. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    749. 

  749. </P>
    750. 

  750. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">do
    751. 

  751. this:</P>
    752. 

  752. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    753. 

  753. </P>
    754. 

  754. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    755. 

  755. </P>
    756. 

  756. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    757. 

  757. </P>
    758. 

  758. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    759. 

  759.  <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">Task
    760. 

  760. t1(TASK_IMMEDIATE, 1000, &amp;callback);</FONT></FONT></P>
    761. 

  761. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    762. 

  762. </P>
    763. 

  763. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    764. 

  764.   
    765. 

  765. </P>
    766. 

  766. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    767. 

  767. </P>
    768. 

  768. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    769. 

  769.  <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">void
    770. 

  770. callback() {</FONT></FONT></P>
    771. 

  771. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    772. 

  772. </P>
    773. 

  773. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    774. 

  774.    <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">int
    775. 

  775. i = t1.getRunCounter() -1;</FONT></FONT></P>
    776. 

  776. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    777. 

  777. </P>
    778. 

  778. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    779. 

  779.    <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">...
    780. 

  780. stuff // one loop action</FONT></FONT></P>
    781. 

  781. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    782. 

  782. </P>
    783. 

  783. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    784. 

  784.  <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">}</FONT></FONT></P>
    785. 

  785. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    786. 

  786. </P>
    787. 

  787. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    788. 

  788. </P>
    789. 

  789. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    790. 

  790. </P>
    791. 

  791. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">or
    792. 

  792. this:</P>
    793. 

  793. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    794. 

  794. </P>
    795. 

  795. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    796. 

  796. </P>
    797. 

  797. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    798. 

  798. </P>
    799. 

  799. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    800. 

  800.  <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">Task
    801. 

  801. t1(TASK_IMMEDIATE, 1000, &amp;callback, true, &amp;t1On);</FONT></FONT></P>
    802. 

  802. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    803. 

  803. </P>
    804. 

  804. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    805. 

  805.  
    806. 

  806. </P>
    807. 

  807. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    808. 

  808. </P>
    809. 

  809. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    810. 

  810.  <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">int
    811. 

  811. i;</FONT></FONT></P>
    812. 

  812. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    813. 

  813. </P>
    814. 

  814. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    815. 

  815.  <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">bool
    816. 

  816. t1On() {</FONT></FONT></P>
    817. 

  817. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    818. 

  818. </P>
    819. 

  819. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    820. 

  820.    <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">i
    821. 

  821. = 0;</FONT></FONT></P>
    822. 

  822. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    823. 

  823. </P>
    824. 

  824. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    825. 

  825.    <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">return
    826. 

  826. true;</FONT></FONT></P>
    827. 

  827. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    828. 

  828. </P>
    829. 

  829. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    830. 

  830.  <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">}</FONT></FONT></P>
    831. 

  831. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    832. 

  832. </P>
    833. 

  833. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    834. 

  834.  
    835. 

  835. </P>
    836. 

  836. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    837. 

  837. </P>
    838. 

  838. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    839. 

  839.  <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">void
    840. 

  840. callback() {</FONT></FONT></P>
    841. 

  841. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    842. 

  842. </P>
    843. 

  843. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    844. 

  844.    <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">...
    845. 

  845. stuff // one loop action</FONT></FONT></P>
    846. 

  846. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    847. 

  847. </P>
    848. 

  848. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    849. 

  849.    <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">i++;</FONT></FONT></P>
    850. 

  850. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    851. 

  851. </P>
    852. 

  852. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    853. 

  853.  <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">}</FONT></FONT></P>
    854. 

  854. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    855. 

  855. </P>
    856. 

  856. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    857. 

  857. </P>
    858. 

  858. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    859. 

  859. </P>
    860. 

  860. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    861. 

  861. </P>
    862. 

  862. <P CLASS="western" ALIGN=CENTER STYLE="margin-left: 0.49in; margin-bottom: 0in">
    863. 

  863. <B>REMEMBER: you are already inside the loop - take advantage of it. </B>
    864. 

  864. </P>
    865. 

  865. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    866. 

  866. </P>
    867. 

  867. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">d)
    868. 

  868. Break long running callback methods into several shorter ones, and
    869. 

  869. pass control from one to the other via <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt"><B>setCallback</B></FONT></FONT><FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">()
    870. 

  870. </FONT></FONT>method:</P>
    871. 

  871. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    872. 

  872. </P>
    873. 

  873. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    874. 

  874. </P>
    875. 

  875. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    876. 

  876. </P>
    877. 

  877. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    878. 

  878.  <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">Task
    879. 

  879. t1(TASK_IMMEDIATE, TASK_FAREVER, &amp;callback);</FONT></FONT></P>
    880. 

  880. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    881. 

  881. </P>
    882. 

  882. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    883. 

  883.  
    884. 

  884. </P>
    885. 

  885. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    886. 

  886. </P>
    887. 

  887. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    888. 

  888.  <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">void
    889. 

  889. callback() {</FONT></FONT></P>
    890. 

  890. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    891. 

  891. </P>
    892. 

  892. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    893. 

  893.    <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">...
    894. 

  894. do some stuff</FONT></FONT></P>
    895. 

  895. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    896. 

  896. </P>
    897. 

  897. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    898. 

  898.    <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">t1.setCallback(&amp;callback_step2);</FONT></FONT></P>
    899. 

  899. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    900. 

  900. </P>
    901. 

  901. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    902. 

  902.  <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">}</FONT></FONT></P>
    903. 

  903. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    904. 

  904. </P>
    905. 

  905. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    906. 

  906.  <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">void
    907. 

  907. callback_step2() {</FONT></FONT></P>
    908. 

  908. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    909. 

  909. </P>
    910. 

  910. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    911. 

  911.    <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">...
    912. 

  912. do more stuff</FONT></FONT></P>
    913. 

  913. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    914. 

  914. </P>
    915. 

  915. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    916. 

  916.    <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">t1.setCallback(&amp;callback_step3);</FONT></FONT></P>
    917. 

  917. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    918. 

  918. </P>
    919. 

  919. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    920. 

  920.  <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">}</FONT></FONT></P>
    921. 

  921. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    922. 

  922. </P>
    923. 

  923. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    924. 

  924.  <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">void
    925. 

  925. callback_step3() {</FONT></FONT></P>
    926. 

  926. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    927. 

  927. </P>
    928. 

  928. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    929. 

  929.    <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">...
    930. 

  930. do last part of the stuff</FONT></FONT></P>
    931. 

  931. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    932. 

  932. </P>
    933. 

  933. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    934. 

  934.    <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">t1.setCallback(&amp;callback);</FONT></FONT></P>
    935. 

  935. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    936. 

  936. </P>
    937. 

  937. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    938. 

  938.    <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">t1.delay(1000);</FONT></FONT></P>
    939. 

  939. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    940. 

  940. </P>
    941. 

  941. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    942. 

  942.  <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">}</FONT></FONT></P>
    943. 

  943. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    944. 

  944. </P>
    945. 

  945. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    946. 

  946. </P>
    947. 

  947. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    948. 

  948. </P>
    949. 

  949. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">This
    950. 

  950. will execute all parts of the callback function in three successive
    951. 

  951. steps, scheduled immediately, but allowing other tasks in the chain
    952. 

  952. to run. Notice that task is scheduled to run immediately, and 1
    953. 

  953. second period is achieved by delaying the task for 1000 millis at the
    954. 

  954. last step. 
    955. 

  955. </P>
    956. 

  956. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    957. 

  957. </P>
    958. 

  958. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Alternatively
    959. 

  959. you could schedule the task to run every 1000 millis and use
    960. 

  960. <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">forceNextIteration()</FONT></FONT>
    961. 

  961. method in steps 1 and 2 (but not 3!)</P>
    962. 

  962. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    963. 

  963. </P>
    964. 

  964. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    965. 

  965. </P>
    966. 

  966. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    967. 

  967. </P>
    968. 

  968. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    969. 

  969.  <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">Task
    970. 

  970. t1(1000, TASK_FOREVER, &amp;callback);</FONT></FONT></P>
    971. 

  971. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    972. 

  972. </P>
    973. 

  973. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    974. 

  974.  
    975. 

  975. </P>
    976. 

  976. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    977. 

  977. </P>
    978. 

  978. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    979. 

  979.  <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">void
    980. 

  980. callback() {</FONT></FONT></P>
    981. 

  981. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    982. 

  982. </P>
    983. 

  983. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    984. 

  984.    <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">...
    985. 

  985. do some stuff</FONT></FONT></P>
    986. 

  986. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    987. 

  987. </P>
    988. 

  988. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    989. 

  989.    <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">t1.setCallback(&amp;callback_step2);</FONT></FONT></P>
    990. 

  990. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    991. 

  991. </P>
    992. 

  992. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    993. 

  993.    <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">t1.forceNextIteration();</FONT></FONT></P>
    994. 

  994. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    995. 

  995. </P>
    996. 

  996. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    997. 

  997.  <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">}</FONT></FONT></P>
    998. 

  998. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    999. 

  999. </P>
    1000. 

  1000. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    1001. 

  1001.  <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">void
    1002. 

  1002. callback_step2() {</FONT></FONT></P>
    1003. 

  1003. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1004. 

  1004. </P>
    1005. 

  1005. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    1006. 

  1006.    <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">...
    1007. 

  1007. do more stuff</FONT></FONT></P>
    1008. 

  1008. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1009. 

  1009. </P>
    1010. 

  1010. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    1011. 

  1011.    <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">t1.setCallback(&amp;callback_step3);</FONT></FONT></P>
    1012. 

  1012. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1013. 

  1013. </P>
    1014. 

  1014. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    1015. 

  1015.    <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">t1.forceNextIteration();</FONT></FONT></P>
    1016. 

  1016. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1017. 

  1017. </P>
    1018. 

  1018. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    1019. 

  1019.  <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">}</FONT></FONT></P>
    1020. 

  1020. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1021. 

  1021. </P>
    1022. 

  1022. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    1023. 

  1023.  <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">void
    1024. 

  1024. callback_step3() {</FONT></FONT></P>
    1025. 

  1025. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1026. 

  1026. </P>
    1027. 

  1027. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    1028. 

  1028.    <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">...
    1029. 

  1029. do last part of the stuff</FONT></FONT></P>
    1030. 

  1030. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1031. 

  1031. </P>
    1032. 

  1032. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    1033. 

  1033.    <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">t1.setCallback(&amp;callback);</FONT></FONT></P>
    1034. 

  1034. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1035. 

  1035. </P>
    1036. 

  1036. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    1037. 

  1037.  <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt">}</FONT></FONT></P>
    1038. 

  1038. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1039. 

  1039. </P>
    1040. 

  1040. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1041. 

  1041. </P>
    1042. 

  1042. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1043. 

  1043. </P>
    1044. 

  1044. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1045. 

  1045. </P>
    1046. 

  1046. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1047. 

  1047. </P>
    1048. 

  1048. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">e)
    1049. 

  1049. Compile the library with <FONT FACE="FreeMono, MS Mincho, monospace"><FONT SIZE=2 STYLE="font-size: 10pt"><B>_TASK_TIMECRITICAL</B></FONT></FONT>
    1050. 

  1050. enabled and check if your tasks are falling behind schedule. If they
    1051. 

  1051. are - you need to optimize your code further (or maybe re-evaluate
    1052. 

  1052. your schedule). If they are not - all is well and you don't need to
    1053. 

  1053. do anything. E.g., I have a spider robot which needs to measure
    1054. 

  1054. distance, control motors, and keep track of the angle via querying
    1055. 

  1055. gyroscope and accelerometer every 10 ms. The idea was to flash
    1056. 

  1056. onboard LED if any of the tasks fall behind. At 10 ms interval for
    1057. 

  1057. the gyro the LED does not flash, which means none of the tasks are
    1058. 

  1058. blocking the others from starting on time. 
    1059. 

  1059. </P>
    1060. 

  1060. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    1061. 

  1061. </P>
    1062. 

  1062. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    1063. 

  1063. </P>
    1064. 

  1064. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    1065. 

  1065. </P>
    1066. 

  1066. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1067. 

  1067. <FONT SIZE=4><B>API DOCUMENTATION:</B></FONT></P>
    1068. 

  1068. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1069. 

  1069. <BR>
    1070. 

  1070. </P>
    1071. 

  1071. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1072. 

  1072. <FONT SIZE=4><B>TASKS:</B></FONT></P>
    1073. 

  1073. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1074. 

  1074. <BR>
    1075. 

  1075. </P>
    1076. 

  1076. <P CLASS="western" STYLE="margin-bottom: 0in">CREATION:</P>
    1077. 

  1077. <P CLASS="western" STYLE="margin-bottom: 0in"><B>Task();</B></P>
    1078. 

  1078. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    1079. 

  1079. </P>
    1080. 

  1080. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Default
    1081. 

  1081. constructor. 
    1082. 

  1082. </P>
    1083. 

  1083. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Takes
    1084. 

  1084. no parameters and creates a task that could be scheduled to run at
    1085. 

  1085. every scheduling pass indefinitely, but does not have a callback
    1086. 

  1086. method defined, so no code execution will actually take place. 
    1087. 

  1087. </P>
    1088. 

  1088. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">All
    1089. 

  1089. tasks are created <B>disabled</B> by default.</P>
    1090. 

  1090. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    1091. 

  1091. </P>
    1092. 

  1092. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1093. 

  1093. <B>Task(unsigned long aInterval, long aIterations, void
    1094. 

  1094. (*aCallback)(), Scheduler* aScheduler, bool aEnable, bool
    1095. 

  1095. (*aOnEnable)(), void (*aOnDisable)())</B></P>
    1096. 

  1096. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    1097. 

  1097. </P>
    1098. 

  1098. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Constructor
    1099. 

  1099. with parameters. 
    1100. 

  1100. </P>
    1101. 

  1101. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Creates
    1102. 

  1102. a task that is scheduled to run every &lt;aInterval&gt; milliseconds,
    1103. 

  1103. &lt;aIterations&gt; times, executing &lt;aCallback&gt; method on
    1104. 

  1104. every pass. 
    1105. 

  1105. </P>
    1106. 

  1106. <OL>
    1107. 

  1107. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in">aInterval is in
    1108. 

  1108. 	milliseconds (<B>default = 0)</B></P>
    1109. 

  1109. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in">aIteration in
    1110. 

  1110. 	number of times, -1 for indefinite execution (<B>default = -1)</B><BR><B>Note:
    1111. 

  1111. 	</B>Tasks do not remember the number of iteration set initially.
    1112. 

  1112. 	After the iterations are done, internal iteration counter is 0. If
    1113. 

  1113. 	you need to perform another set of iterations, you need to set the
    1114. 

  1114. 	number of iterations again. <BR><B>Note: </B>Tasks which performed
    1115. 

  1115. 	all their iterations remain active. 
    1116. 

  1116. 	</P>
    1117. 

  1117. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in">aCallback is a
    1118. 

  1118. 	pointer to a void callback method without parameters (<B>default =
    1119. 

  1119. 	NULL)</B></P>
    1120. 

  1120. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in">aScheduler –
    1121. 

  1121. 	<B>optional</B> reference to existing scheduler. If supplied (not
    1122. 

  1122. 	NULL) this task will be appended to the task chain of the current
    1123. 

  1123. 	scheduler). (<B>default = NULL)</B></P>
    1124. 

  1124. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in">aEnable –
    1125. 

  1125. 	<B>optional</B>. Value of <B>true </B>will create task enabled.
    1126. 

  1126. 	(<B>default = false)</B></P>
    1127. 

  1127. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in">aOnEnable is a
    1128. 

  1128. 	pointer to a bool callback method without parameters, invoked when
    1129. 

  1129. 	task is enabled. If OnEnable method returns <B>true</B>, task is
    1130. 

  1130. 	enabled. If <B>OnEnable</B> method return <B>false</B>, task remains
    1131. 

  1131. 	disabled (<B>default = NULL)</B></P>
    1132. 

  1132. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in">aOnDisable is a
    1133. 

  1133. 	pointer to a void callback method without parameters, invoked when
    1134. 

  1134. 	task is disabled (<B>default = NULL)</B></P>
    1135. 

  1135. </OL>
    1136. 

  1136. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1137. 

  1137. </P>
    1138. 

  1138. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">All
    1139. 

  1139. tasks are created <B>disabled</B> by default (unless <B>aEnable</B> =
    1140. 

  1140. true). You have to explicitly enable the task for execution.</P>
    1141. 

  1141. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1142. 

  1142. </P>
    1143. 

  1143. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><B>NOTE:
    1144. 

  1144. </B>OnEnable callback method is called immediately when task is
    1145. 

  1145. enabled, which could be well ahead of the scheduled execution time of
    1146. 

  1146. the task. Please bear that in mind – other tasks, hardware, serial
    1147. 

  1147. interface may not even be initialized yet. It is always advisable to
    1148. 

  1148. explicitly enable tasks with OnEnable methods after all
    1149. 

  1149. initialization methods completed (e.g., at the end of <B>setup</B>()
    1150. 

  1150. method) 
    1151. 

  1151. </P>
    1152. 

  1152. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1153. 

  1153. </P>
    1154. 

  1154. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Enabled
    1155. 

  1155. task is scheduled for execution as soon as the Scheduler's <B>execute</B>()
    1156. 

  1156. methods gets control. In order to delay first run of the task, use
    1157. 

  1157. <B>enableDelayed</B> or <B>delay</B> method (for enabled tasks)
    1158. 

  1158. method.</P>
    1159. 

  1159. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1160. 

  1160. </P>
    1161. 

  1161. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1162. 

  1162. <B>Task(void (*aCallback)(), Scheduler* aScheduler, bool
    1163. 

  1163. (*aOnEnable)(), void (*aOnDisable)())</B></P>
    1164. 

  1164. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1165. 

  1165. </P>
    1166. 

  1166. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">If
    1167. 

  1167. compiled with support for Status Request objects, this constructor
    1168. 

  1168. creates a Task for activation on event (since such tasks must run
    1169. 

  1169. <B>waitFor() </B>method, their <I>interval</I>, <I>iteration</I> and
    1170. 

  1170. <I>enabled</I> status will be set by that method (<I>to 0, 1 and
    1171. 

  1171. false</I> respectively).</P>
    1172. 

  1172. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1173. 

  1173. </P>
    1174. 

  1174. <P CLASS="western" STYLE="margin-bottom: 0in"><B>INFORMATION</B></P>
    1175. 

  1175. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">The
    1176. 

  1176. following 3 “getter” methods return task status
    1177. 

  1177. (enabled/disabled), execution interval in milliseconds, number of
    1178. 

  1178. <I><B>remaining</B></I> iterations. 
    1179. 

  1179. </P>
    1180. 

  1180. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1181. 

  1181. </P>
    1182. 

  1182. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><B>bool
    1183. 

  1183. isEnabled() </B>
    1184. 

  1184. </P>
    1185. 

  1185. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><B>unsigned
    1186. 

  1186. long getInterval()</B></P>
    1187. 

  1187. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><B>long
    1188. 

  1188. getIterations() </B>
    1189. 

  1189. </P>
    1190. 

  1190. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1191. 

  1191. </P>
    1192. 

  1192. <P CLASS="western" STYLE="margin-bottom: 0in"><B>long getStartDelay()</B></P>
    1193. 

  1193. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">If
    1194. 

  1194. library is compiled with <FONT FACE="Courier New, monospace">_TASK_TIMECRITICAL</FONT>
    1195. 

  1195. enabled, you can assess how much later the callback method was
    1196. 

  1196. invoked against when it was scheduled to be invoked. The return value
    1197. 

  1197. of  <B>getStartDelay () </B>method provides this information in
    1198. 

  1198. milliseconds. 
    1199. 

  1199. </P>
    1200. 

  1200. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    1201. 

  1201. </P>
    1202. 

  1202. <P CLASS="western" STYLE="margin-bottom: 0in"><B>long getOverrun()</B></P>
    1203. 

  1203. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">If
    1204. 

  1204. library is compiled with <FONT FACE="Courier New, monospace">_TASK_TIMECRITICAL</FONT>
    1205. 

  1205. enabled, tasks are monitored for “long running” scenario. A “long
    1206. 

  1206. running” task is a task that does not finish processing its
    1207. 

  1207. callback methods quickly, and thus creates a situation for itself and
    1208. 

  1208. other tasks where they don't run on a scheduled interval, but rather
    1209. 

  1209. “catch up” and are behind.  When task scheduler sets the next
    1210. 

  1210. execution target time, it adds Task's execution interval to the
    1211. 

  1211. previously scheduled execution time:</P>
    1212. 

  1212. <P CLASS="western" ALIGN=CENTER STYLE="margin-left: 0.49in; margin-bottom: 0in">
    1213. 

  1213. <B>next execution time = current execution scheduled time + task
    1214. 

  1214. execution interval</B></P>
    1215. 

  1215. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1216. 

  1216. </P>
    1217. 

  1217. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">If
    1218. 

  1218. <B>next execution time</B> happens to be already in the past (<B>next
    1219. 

  1219. execution time</B> &lt; <B>millis()</B>), then task is considered
    1220. 

  1220. <I><B>overrun</B></I>. <B>GetOverrun</B> method returns number of
    1221. 

  1221. milliseconds between next execution time and current time. If the
    1222. 

  1222. <B>value is negative</B>, the task has overrun (cut into the) next
    1223. 

  1223. execution interval by that many milliseconds. 
    1224. 

  1224. </P>
    1225. 

  1225. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Positive
    1226. 

  1226. value indicate number of milliseconds of slack this task has for
    1227. 

  1227. execution purposes. 
    1228. 

  1228. </P>
    1229. 

  1229. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1230. 

  1230. </P>
    1231. 

  1231. <P CLASS="western" STYLE="margin-bottom: 0in"><B>unsigned long
    1232. 

  1232. getRunCounter()</B></P>
    1233. 

  1233. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Returns
    1234. 

  1234. the number of the current run. “Current run” is the number of
    1235. 

  1235. times a callback method has been invoked since the last time a task
    1236. 

  1236. was enabled. <BR><BR>
    1237. 

  1237. </P>
    1238. 

  1238. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><B>NOTE:
    1239. 

  1239. </B>The <B>runCounter</B> value is incremented <I>before</I> callback
    1240. 

  1240. method is invoked. If a task is checking the <B>runCounter</B> value
    1241. 

  1241. within its callback method, then the first run value is 1. 
    1242. 

  1242. </P>
    1243. 

  1243. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">If
    1244. 

  1244. task T1 is checking the <B>runCounter</B> value of another task (T2)
    1245. 

  1245. , then value = 0 indicates that T2 has not been invoked yet, and
    1246. 

  1246. value = 1 indicates that T2 has run once. 
    1247. 

  1247. </P>
    1248. 

  1248. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    1249. 

  1249. </P>
    1250. 

  1250. <P CLASS="western" STYLE="margin-bottom: 0in"><B>bool
    1251. 

  1251. isFirstIteration()</B></P>
    1252. 

  1252. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Indicates
    1253. 

  1253. whether current pass is (or will be) a first iteration of the task. 
    1254. 

  1254. </P>
    1255. 

  1255. <P CLASS="western" STYLE="margin-bottom: 0in"><B>bool
    1256. 

  1256. isLastIteration()</B></P>
    1257. 

  1257. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">For
    1258. 

  1258. tasks with a l<I>imited number of iterations only</I>, indicates
    1259. 

  1259. whether current pass is the last iteration. 
    1260. 

  1260. </P>
    1261. 

  1261. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    1262. 

  1262. </P>
    1263. 

  1263. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1264. 

  1264. <B>CONTROL:</B></P>
    1265. 

  1265. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1266. 

  1266. <BR>
    1267. 

  1267. </P>
    1268. 

  1268. <P CLASS="western" STYLE="margin-bottom: 0in"><B>void enable();</B></P>
    1269. 

  1269. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    1270. 

  1270. </P>
    1271. 

  1271. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Enables
    1272. 

  1272. the task, and schedules it for immediate execution (without delay) at
    1273. 

  1273. this or next scheduling pass depending on when the task was enabled.
    1274. 

  1274. Scheduler will execute the next pass without any delay because there
    1275. 

  1275. is a task which was enabled and requires execution. 
    1276. 

  1276. </P>
    1277. 

  1277. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1278. 

  1278. </P>
    1279. 

  1279. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><B>NOTE:
    1280. 

  1280. </B>if task being enabled is not assigned to a scheduler and is not
    1281. 

  1281. part of execution chain, then task <B>will not</B> be enabled.</P>
    1282. 

  1282. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1283. 

  1283. </P>
    1284. 

  1284. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><B>NOTE:
    1285. 

  1285. </B>enable() invokes task’s <B>OnEnable</B> method (if not NULL)
    1286. 

  1286. <B>immediately</B>, which can prepare task for execution. <B>OnEnable</B>
    1287. 

  1287. must return a value of <B>true</B> for task to be enabled. If
    1288. 

  1288. <B>OnEnable</B> returns <B>false</B>, task remains disabled. 
    1289. 

  1289. <B>OnEnable</B> is invoked every time <B>enable</B> is called,
    1290. 

  1290. regardless if task is already enabled or not. Alignment to current
    1291. 

  1291. millis() is performed after <B>OnEnable</B> exits, so any changes to
    1292. 

  1292. the interval inside <B>OnEnable</B> is taken into consideration.</P>
    1293. 

  1293. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">TaskScheduler
    1294. 

  1294. allows tasks to be added to the a Scheduler and enabled at the time
    1295. 

  1295. of creation. <B>Be very careful</B> with such tasks – the <B>OnEnable
    1296. 

  1296. </B>method will be executed immediately, while certain objects (i.e.,
    1297. 

  1297. other Tasks, libraries) are not yet ready (e.g., <B>Wire.begin()</B>
    1298. 

  1298. was not yet called), or hardware not yet activated (pins not set to
    1299. 

  1299. INPUT or OUTPUT). 
    1300. 

  1300. </P>
    1301. 

  1301. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">It
    1302. 

  1302. is very much recommended to to enable all tasks at the end of <B>setup()</B>
    1303. 

  1303. method after all initializations are done. 
    1304. 

  1304. </P>
    1305. 

  1305. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">If
    1306. 

  1306. you require immediate execution of already enabled task, use
    1307. 

  1307. <B>forceNextIteratoin</B>() method instead of <B>enable</B>(): it
    1308. 

  1308. achieves the result, but does not call <B>OnEnable</B> method. 
    1309. 

  1309. </P>
    1310. 

  1310. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1311. 

  1311. </P>
    1312. 

  1312. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><B>NOTE:</B>
    1313. 

  1313. in the event <B>enable</B>() method is called inside the <B>OnEnable</B>
    1314. 

  1314. callback method (thus basically creating indefinte loop),
    1315. 

  1315. TaskScheduler will only call <B>OnEnable</B> once (thus protecting
    1316. 

  1316. the Task against <B>OnEnable</B> infinite loop). 
    1317. 

  1317. </P>
    1318. 

  1318. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1319. 

  1319. </P>
    1320. 

  1320. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1321. 

  1321. <B>bool enableIfNot();</B></P>
    1322. 

  1322. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1323. 

  1323. <BR>
    1324. 

  1324. </P>
    1325. 

  1325. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Enables
    1326. 

  1326. the task only if it was previously disabled. Returns previous enable
    1327. 

  1327. state: <B>true</B> if task was already enabled, and <B>false</B> if
    1328. 

  1328. task was disabled. Since <B>enable() </B>schedules Task for execution
    1329. 

  1329. immediately, this method provides a way to activate tasks and
    1330. 

  1330. schedule them for immediate execution only if they are not active
    1331. 

  1331. already.</P>
    1332. 

  1332. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    1333. 

  1333. </P>
    1334. 

  1334. <P CLASS="western" STYLE="margin-bottom: 0in"><B>void delay();</B></P>
    1335. 

  1335. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    1336. 

  1336. </P>
    1337. 

  1337. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Schedules
    1338. 

  1338. the task for execution after a delay (aInterval), but does not change
    1339. 

  1339. the enabled/disabled status of the task. 
    1340. 

  1340. </P>
    1341. 

  1341. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1342. 

  1342. </P>
    1343. 

  1343. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><B>NOTE:
    1344. 

  1344. </B>a delay of 0 (zero) will delay task for current execution
    1345. 

  1345. interval. Use <B>forceNextIteration() </B>method to force execution
    1346. 

  1346. of the task’s callback during immediate next scheduling pass. 
    1347. 

  1347. </P>
    1348. 

  1348. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1349. 

  1349. </P>
    1350. 

  1350. <P CLASS="western" STYLE="margin-bottom: 0in"><B>void
    1351. 

  1351. forceNextIteration();</B></P>
    1352. 

  1352. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    1353. 

  1353. </P>
    1354. 

  1354. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Schedules
    1355. 

  1355. the task for execution during immediate next scheduling pass.</P>
    1356. 

  1356. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">The
    1357. 

  1357. Task must be already <I>enabled</I> prior to this method. 
    1358. 

  1358. </P>
    1359. 

  1359. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1360. 

  1360. </P>
    1361. 

  1361. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><B>Note:
    1362. 

  1362. </B>Task’s schedule is adjusted to run from this moment in time.
    1363. 

  1363. For instance: if a task was running every 10 seconds: 10, 20, 30, ..,
    1364. 

  1364. calling <B>forceNextIteration </B>at 44th second of task execution
    1365. 

  1365. will make subsequent schedule  look like: 44, 54, 64, 74, ..</P>
    1366. 

  1366. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1367. 

  1367. </P>
    1368. 

  1368. <P CLASS="western" STYLE="margin-bottom: 0in"><B>void
    1369. 

  1369. enableDelayed();</B></P>
    1370. 

  1370. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    1371. 

  1371. </P>
    1372. 

  1372. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Enables
    1373. 

  1373. the task, and schedules it for execution after task's current
    1374. 

  1374. scheduling interval (aInterval). 
    1375. 

  1375. </P>
    1376. 

  1376. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1377. 

  1377. </P>
    1378. 

  1378. <P CLASS="western" STYLE="margin-bottom: 0in"><B>void enableDelayed
    1379. 

  1379. (unsigned long aDelay);</B></P>
    1380. 

  1380. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    1381. 

  1381. </P>
    1382. 

  1382. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Enables
    1383. 

  1383. the task, and schedules it for execution after a specific delay
    1384. 

  1384. (aDelay, which maybe different from aInterval). 
    1385. 

  1385. </P>
    1386. 

  1386. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1387. 

  1387. </P>
    1388. 

  1388. <P CLASS="western" STYLE="margin-bottom: 0in"><B>void restart();</B></P>
    1389. 

  1389. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    1390. 

  1390. </P>
    1391. 

  1391. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">For
    1392. 

  1392. tasks with limited number of iterations only, <B>restart</B> method
    1393. 

  1393. will re-enable the task, set the number of iterations back to last
    1394. 

  1394. set value, and schedule task for execution as soon as possible.</P>
    1395. 

  1395. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1396. 

  1396. </P>
    1397. 

  1397. <P CLASS="western" STYLE="margin-bottom: 0in"><B>void restartDelayed
    1398. 

  1398. (unsigned long aDelay);</B></P>
    1399. 

  1399. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    1400. 

  1400. </P>
    1401. 

  1401. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Same
    1402. 

  1402. as <B>restart()</B> method, with the only difference being that Task
    1403. 

  1403. is scheduled to run first iteration after a delay = <B>aDelay</B>
    1404. 

  1404. milliseconds.</P>
    1405. 

  1405. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    1406. 

  1406. </P>
    1407. 

  1407. <P CLASS="western" STYLE="margin-bottom: 0in"><B>bool disable();</B></P>
    1408. 

  1408. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    1409. 

  1409. </P>
    1410. 

  1410. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Disables
    1411. 

  1411. the task. Scheduler will not execute this task any longer, even if it
    1412. 

  1412. remains in the chain.  Task <B>can</B> be later re-enabled for
    1413. 

  1413. execution. 
    1414. 

  1414. </P>
    1415. 

  1415. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Return
    1416. 

  1416. previous enabled state: <B>true</B> if task was enabled prior to
    1417. 

  1417. calling disable, and <B>false</B> otherwise.</P>
    1418. 

  1418. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">If
    1419. 

  1419. not NULL, task’s <B>OnDisable</B> method is invoked <B>immediately</B>.
    1420. 

  1420. <B>OnDisable</B> is invoked only if task was in enabled state. 
    1421. 

  1421. Calling <B>disable</B> 3 times for instance will invoke <B>OnDisable</B>
    1422. 

  1422. only once.</P>
    1423. 

  1423. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1424. 

  1424. </P>
    1425. 

  1425. <P CLASS="western" STYLE="margin-bottom: 0in"><B>void set(unsigned
    1426. 

  1426. long aInterval, long aIterations, void (*aCallback)() , bool
    1427. 

  1427. (*aOnEnable)() , void (*aOnDisable)());</B></P>
    1428. 

  1428. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    1429. 

  1429. </P>
    1430. 

  1430. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Allows
    1431. 

  1431. dynamic control of task execution parameters in one method call. 
    1432. 

  1432. </P>
    1433. 

  1433. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><B>Note</B><B>:
    1434. 

  1434. </B>OnEnable and OnDisable parameters can be omitted. In that case
    1435. 

  1435. they will be assigned to <B>NULL</B> and respective methods will no
    1436. 

  1436. longer be called. Therefore it is advisable to use either all five
    1437. 

  1437. parameters explicitly, or employ individual “setter” methods
    1438. 

  1438. below instead. 
    1439. 

  1439. </P>
    1440. 

  1440. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1441. 

  1441. </P>
    1442. 

  1442. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1443. 

  1443. Next five “setter” methods allow changes of individual task
    1444. 

  1444. execution control parameters. 
    1445. 

  1445. </P>
    1446. 

  1446. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><B>void
    1447. 

  1447. setInterval (unsigned long aInterval) </B>
    1448. 

  1448. </P>
    1449. 

  1449. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><B>void
    1450. 

  1450. setIterations (long aIterations) </B>
    1451. 

  1451. </P>
    1452. 

  1452. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><B>void
    1453. 

  1453. setCallback (void (*aCallback)()) </B>
    1454. 

  1454. </P>
    1455. 

  1455. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><B>void
    1456. 

  1456. setOnEnable (bool (*aCallback)()) </B>
    1457. 

  1457. </P>
    1458. 

  1458. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><B>void
    1459. 

  1459. setOnDisable (void (*aCallback)()) </B>
    1460. 

  1460. </P>
    1461. 

  1461. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    1462. 

  1462. </P>
    1463. 

  1463. <P CLASS="western" STYLE="margin-bottom: 0in"><B>NOTE: </B>Next
    1464. 

  1464. execution time calculation takes place <B>after</B> the callback
    1465. 

  1465. method is called, so new interval will be used immediately by the
    1466. 

  1466. scheduler. For the situations when one task is changing the interval
    1467. 

  1467. parameter for the other, <B>setInterval</B> method calls <B>delay
    1468. 

  1468. </B>explicitly to guarantee schedule change, however it <B>does not
    1469. 

  1469. </B>enable the task if task is disabled.</P>
    1470. 

  1470. <P CLASS="western" STYLE="margin-bottom: 0in"><B>NOTE: </B>Tasks that
    1471. 

  1471. ran through all their allocated iterations are disabled.
    1472. 

  1472. <B>SetIterations()</B> method <B>DOES NOT</B> enable the task. Either
    1473. 

  1473. <B>enable</B> explicitly, or use <B>restart</B> methods. 
    1474. 

  1474. </P>
    1475. 

  1475. <P CLASS="western" STYLE="margin-bottom: 0in">Please note that as a
    1476. 

  1476. result execution of the taks is <B>delayed</B> by the provided
    1477. 

  1477. interval. If immediate invocation is required, call
    1478. 

  1478. <B>forceNextIteration</B>() method after setting a new interval. 
    1479. 

  1479. </P>
    1480. 

  1480. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    1481. 

  1481. </P>
    1482. 

  1482. <P CLASS="western" STYLE="margin-bottom: 0in"><B>STATUS REQUEST
    1483. 

  1483. METHODS:</B></P>
    1484. 

  1484. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1485. 

  1485. <BR>
    1486. 

  1486. </P>
    1487. 

  1487. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1488. 

  1488. <B>void waitFor(StatusRequest* aStatusRequest, unsigned long
    1489. 

  1489. aInterval = 0, long aIterations = 1)</B></P>
    1490. 

  1490. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1491. 

  1491. <B>void waitForDelayed(StatusRequest* aStatusRequest, unsigned long
    1492. 

  1492. aInterval = 0, long aIterations = 1)</B></P>
    1493. 

  1493. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1494. 

  1494. <BR>
    1495. 

  1495. </P>
    1496. 

  1496. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">If
    1497. 

  1497. compiled with support for Status Requests, these methods make task
    1498. 

  1498. wait for the completion of <B>aStatusRequest</B> event. 
    1499. 

  1499. </P>
    1500. 

  1500. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">By
    1501. 

  1501. default <B>waitFor() </B>sets tasks interval to <B>0 (zero)</B> for
    1502. 

  1502. immediate execution when event happens, and also sets the number of
    1503. 

  1503. <B>iterations to 1</B>. However, you can specify different interval
    1504. 

  1504. and number of iterations. 
    1505. 

  1505. </P>
    1506. 

  1506. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">By
    1507. 

  1507. default <B>waitForDelayed() </B>sets tasks interval to a supplied
    1508. 

  1508. value or (if omitted or zero) keeps the current interval, so delayed
    1509. 

  1509. execution will take place when the event happens.  It also sets the
    1510. 

  1510. number of <B>iterations to 1</B> by default if not supplied.  
    1511. 

  1511. </P>
    1512. 

  1512. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">When
    1513. 

  1513. Status Request object completes, all tasks waiting on it are executed
    1514. 

  1514. during next scheduling pass. Tasks waiting via <B>waitFor</B>()
    1515. 

  1515. method are executed immediately. Tasks waiting via <B>waitForDelayed</B>()
    1516. 

  1516. method are activated, but executed after current or supplied interval
    1517. 

  1517. delay. 
    1518. 

  1518. </P>
    1519. 

  1519. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><B>Note:
    1520. 

  1520. aStatusRequest</B> should be “activated” by calling <B>setWaiting()
    1521. 

  1521. </B>method before making a task wait on it. Otherwise, the task will
    1522. 

  1522. execute immediately. 
    1523. 

  1523. </P>
    1524. 

  1524. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">The
    1525. 

  1525. sequence of events to use Status Request object is as follows:</P>
    1526. 

  1526. <OL>
    1527. 

  1527. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in">Create a status
    1528. 

  1528. 	request object</P>
    1529. 

  1529. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in">Activate status
    1530. 

  1530. 	request object (calling its <B>setWaiting</B>() method)</P>
    1531. 

  1531. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in">Set up tasks to
    1532. 

  1532. 	wait of the event completion</P>
    1533. 

  1533. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in">Signal completion
    1534. 

  1534. 	of event(s)</P>
    1535. 

  1535. </OL>
    1536. 

  1536. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    1537. 

  1537. </P>
    1538. 

  1538. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    1539. 

  1539. </P>
    1540. 

  1540. <P CLASS="western" STYLE="margin-bottom: 0in"><B>StatusRequest*
    1541. 

  1541. getStatusRequest()</B></P>
    1542. 

  1542. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Returns
    1543. 

  1543. a StatusReqeust object this Task was waiting on. 
    1544. 

  1544. </P>
    1545. 

  1545. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1546. 

  1546. </P>
    1547. 

  1547. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1548. 

  1548. </P>
    1549. 

  1549. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1550. 

  1550. </P>
    1551. 

  1551. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1552. 

  1552. <B>TASK ID, CONTROL POINTS METHODS:</B></P>
    1553. 

  1553. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1554. 

  1554. <BR>
    1555. 

  1555. </P>
    1556. 

  1556. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1557. 

  1557. <B>void setId(unsigned int aID);</B></P>
    1558. 

  1558. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1559. 

  1559. <BR>
    1560. 

  1560. </P>
    1561. 

  1561. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">If
    1562. 

  1562. compiled with support for Task IDs, this method will set the task ID
    1563. 

  1563. explicitly. 
    1564. 

  1564. </P>
    1565. 

  1565. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Calling
    1566. 

  1566. this method is not necessary as task IDs are assigned automatically
    1567. 

  1567. during task creation: 1, 2, 3, …</P>
    1568. 

  1568. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    1569. 

  1569. </P>
    1570. 

  1570. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1571. 

  1571. <B>unsigned int getId();</B></P>
    1572. 

  1572. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1573. 

  1573. <BR>
    1574. 

  1574. </P>
    1575. 

  1575. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">If
    1576. 

  1576. compiled with support for Task IDs, this method return current task’s
    1577. 

  1577. ID.</P>
    1578. 

  1578. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1579. 

  1579. </P>
    1580. 

  1580. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1581. 

  1581. <B>void setControlPoint (unsigned int aPoint);</B></P>
    1582. 

  1582. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1583. 

  1583. <BR>
    1584. 

  1584. </P>
    1585. 

  1585. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">If
    1586. 

  1586. compiled with support for Task IDs, this method will set a control
    1587. 

  1587. point in the task’s code. Control points are similar to “try…catch”
    1588. 

  1588. blocks, with control point ID specifying where in the code the “try”
    1589. 

  1589. part started, and a mechanism like watchdog timer providing the
    1590. 

  1590. “catch” functionality.</P>
    1591. 

  1591. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1592. 

  1592. </P>
    1593. 

  1593. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1594. 

  1594. <B>unsigned int getControlPoint()</B></P>
    1595. 

  1595. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in; page-break-after: avoid">
    1596. 

  1596. <BR>
    1597. 

  1597. </P>
    1598. 

  1598. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in; page-break-after: avoid">
    1599. 

  1599. If compiled with support for Task IDs, this method will return
    1600. 

  1600. currently set control point for this task.</P>
    1601. 

  1601. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1602. 

  1602. <BR>
    1603. 

  1603. </P>
    1604. 

  1604. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1605. 

  1605. <BR>
    1606. 

  1606. </P>
    1607. 

  1607. <P CLASS="western" STYLE="margin-bottom: 0in"><B>LOCAL TASK STORAGE
    1608. 

  1608. METHODS:</B></P>
    1609. 

  1609. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1610. 

  1610. <BR>
    1611. 

  1611. </P>
    1612. 

  1612. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1613. 

  1613. <B>void setLtsPointer(void *aPtr);</B></P>
    1614. 

  1614. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1615. 

  1615. <BR>
    1616. 

  1616. </P>
    1617. 

  1617. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">If
    1618. 

  1618. compiled with support for LTS, this method will set the task's local
    1619. 

  1619. storage pointer.</P>
    1620. 

  1620. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    1621. 

  1621. </P>
    1622. 

  1622. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1623. 

  1623. <B>void *getLtsPointer();</B></P>
    1624. 

  1624. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1625. 

  1625. <BR>
    1626. 

  1626. </P>
    1627. 

  1627. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">If
    1628. 

  1628. compiled with support for LTS, this method will return reference to
    1629. 

  1629. the task's local storage.</P>
    1630. 

  1630. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><B>Note:
    1631. 

  1631. </B>the value returned has type (void *), and needs to be re-cast
    1632. 

  1632. into appropriate pointer type. Please refer to example sketches for
    1633. 

  1633. implementation options. 
    1634. 

  1634. </P>
    1635. 

  1635. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1636. 

  1636. </P>
    1637. 

  1637. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1638. 

  1638. </P>
    1639. 

  1639. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1640. 

  1640. </P>
    1641. 

  1641. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1642. 

  1642. <B>STATUS REQUEST:</B></P>
    1643. 

  1643. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1644. 

  1644. <BR>
    1645. 

  1645. </P>
    1646. 

  1646. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1647. 

  1647. <B>CREATION:</B></P>
    1648. 

  1648. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1649. 

  1649. <BR>
    1650. 

  1650. </P>
    1651. 

  1651. <P CLASS="western" STYLE="margin-bottom: 0in"><B>StatusRequest()</B><BR><BR>
    1652. 

  1652. </P>
    1653. 

  1653. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Default
    1654. 

  1654. constructor. 
    1655. 

  1655. </P>
    1656. 

  1656. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Takes
    1657. 

  1657. no parameters. Creates Status Request object, which is assigned a
    1658. 

  1658. status of “completed” on creation. 
    1659. 

  1659. </P>
    1660. 

  1660. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1661. 

  1661. </P>
    1662. 

  1662. <P CLASS="western" STYLE="margin-bottom: 0in"><B>void
    1663. 

  1663. setWaiting(unsigned int aCount = 1)</B></P>
    1664. 

  1664. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Activates
    1665. 

  1665. Status Request object. By default each object is set to wait on one
    1666. 

  1666. event only, however, if <B>aCount</B> is supplied, Status Request can
    1667. 

  1667. wait on multiple events. For instance, <B>setWaiting(3)</B> will wait
    1668. 

  1668. on three signals. An example could be waiting for completion of
    1669. 

  1669. measurements from 3 sensors. 
    1670. 

  1670. </P>
    1671. 

  1671. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1672. 

  1672. </P>
    1673. 

  1673. <P CLASS="western" STYLE="margin-bottom: 0in"><B>bool signal(int
    1674. 

  1674. aStatus)</B></P>
    1675. 

  1675. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Signals
    1676. 

  1676. completion of the event to the Status Request object, and passes a
    1677. 

  1677. completion code, which could be interrogated later. 
    1678. 

  1678. </P>
    1679. 

  1679. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><B>Note:
    1680. 

  1680. </B> passing a <B>negative</B> status code to the status request
    1681. 

  1681. object is considered reporting an error condition, and will complete
    1682. 

  1682. the status request regardless of how many outstanding signals it is
    1683. 

  1683. still waiting for. 
    1684. 

  1684. </P>
    1685. 

  1685. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><B>Note</B>:
    1686. 

  1686. only the latest status code is kept.</P>
    1687. 

  1687. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1688. 

  1688. </P>
    1689. 

  1689. <P CLASS="western" STYLE="margin-bottom: 0in"><B>bool signalComplete
    1690. 

  1690. (int aStatus)</B></P>
    1691. 

  1691. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Signals
    1692. 

  1692. completion of <B>ALL</B> events to the Status Request object, and
    1693. 

  1693. passes a completion code, which could be interrogated later. The
    1694. 

  1694. status request completes regardless of how many events it is still
    1695. 

  1695. waiting on. 
    1696. 

  1696. </P>
    1697. 

  1697. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1698. 

  1698. </P>
    1699. 

  1699. <P CLASS="western" STYLE="margin-bottom: 0in"><B>bool pending() </B>
    1700. 

  1700. </P>
    1701. 

  1701. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Returns
    1702. 

  1702. <B>true</B> if status request is still waiting for event or events to
    1703. 

  1703. happen.</P>
    1704. 

  1704. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1705. 

  1705. </P>
    1706. 

  1706. <P CLASS="western" STYLE="margin-bottom: 0in"><B>bool completed () </B>
    1707. 

  1707. </P>
    1708. 

  1708. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Returns
    1709. 

  1709. <B>true</B> if status has completed.</P>
    1710. 

  1710. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1711. 

  1711. </P>
    1712. 

  1712. <P CLASS="western" STYLE="margin-bottom: 0in"><B>int getStatus()</B></P>
    1713. 

  1713. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Returns
    1714. 

  1714. the status code passed to the status request object by the <B>signal()
    1715. 

  1715. </B>and <B>signalComplete() </B>methods. 
    1716. 

  1716. </P>
    1717. 

  1717. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Any
    1718. 

  1718. <B>positive</B> number is considered a successful completion status.</P>
    1719. 

  1719. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">A
    1720. 

  1720. 0 (zero) is considered a default successful completion status.</P>
    1721. 

  1721. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Any
    1722. 

  1722. <B>negative</B> number is considered an error code and unsuccessful
    1723. 

  1723. completion of a request.</P>
    1724. 

  1724. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    1725. 

  1725. </P>
    1726. 

  1726. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    1727. 

  1727. </P>
    1728. 

  1728. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1729. 

  1729. <BR>
    1730. 

  1730. </P>
    1731. 

  1731. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-inside: avoid; page-break-after: avoid">
    1732. 

  1732. <FONT SIZE=4><B>TASK SCHEDULER:</B></FONT></P>
    1733. 

  1733. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-inside: avoid; page-break-after: avoid">
    1734. 

  1734. <BR>
    1735. 

  1735. </P>
    1736. 

  1736. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-inside: avoid; page-break-after: avoid">
    1737. 

  1737. <B>CREATION:</B></P>
    1738. 

  1738. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-inside: avoid; page-break-after: avoid">
    1739. 

  1739. <BR>
    1740. 

  1740. </P>
    1741. 

  1741. <P CLASS="western" STYLE="margin-bottom: 0in"><B>Scheduler()</B><BR><BR>
    1742. 

  1742. </P>
    1743. 

  1743. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Default
    1744. 

  1744. constructor. 
    1745. 

  1745. </P>
    1746. 

  1746. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Takes
    1747. 

  1747. no parameters. Creates task scheduler with default parameters and an
    1748. 

  1748. empty task queue. 
    1749. 

  1749. </P>
    1750. 

  1750. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1751. 

  1751. </P>
    1752. 

  1752. <P CLASS="western" STYLE="margin-bottom: 0in"><B>void init()</B></P>
    1753. 

  1753. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1754. 

  1754. </P>
    1755. 

  1755. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Initializes
    1756. 

  1756. the task queue and scheduler parameters, Executed as part of
    1757. 

  1757. constructor, so don't need to be explicitly called after creation.</P>
    1758. 

  1758. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><B>Note:
    1759. 

  1759. </B>be default (if compiled with <FONT FACE="Courier New, monospace">_TASK_TIMECRITICAL</FONT>
    1760. 

  1760. enabled) scheduler is allowed to put processor to IDLE sleep mode. If
    1761. 

  1761. this behavior was changed via <B>allowSleep()</B> method, <B>inti()
    1762. 

  1762. </B>will <B>NOT</B> reset allow sleep particular parameter. 
    1763. 

  1763. </P>
    1764. 

  1764. <P CLASS="western" STYLE="margin-bottom: 0in"><BR><B>void
    1765. 

  1765. addTask(Task&amp; aTask)</B></P>
    1766. 

  1766. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1767. 

  1767. </P>
    1768. 

  1768. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Adds
    1769. 

  1769. task aTask to the execution queue (or chain) of tasks by appending it
    1770. 

  1770. to the end of the chain. If two tasks are scheduled for execution,
    1771. 

  1771. the sequence will match the order in which tasks were appended to the
    1772. 

  1772. chain. However, in reality, due to different timing of task
    1773. 

  1773. execution, the actual order may be different. 
    1774. 

  1774. </P>
    1775. 

  1775. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><B>Note:
    1776. 

  1776. </B>Currently, changing the execution sequence in a chain dynamically
    1777. 

  1777. is not supported. 
    1778. 

  1778. </P>
    1779. 

  1779. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">If
    1780. 

  1780. you need to reorder the chain sequence – initialize the scheduler
    1781. 

  1781. and re-add the tasks in a different order. 
    1782. 

  1782. </P>
    1783. 

  1783. <P CLASS="western" STYLE="margin-bottom: 0in"><BR><B>void
    1784. 

  1784. deleteTask(Task&amp; aTask)</B></P>
    1785. 

  1785. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1786. 

  1786. </P>
    1787. 

  1787. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Deletes
    1788. 

  1788. task aTask from the execution chain. The chain of remaining tasks is
    1789. 

  1789. linked together (i.e</P>
    1790. 

  1790. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">if
    1791. 

  1791. original task chain is 1 → 2 → 3 → 4, deleting 3 will result in
    1792. 

  1792. 1 → 2 → 4).</P>
    1793. 

  1793. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><B>Note:
    1794. 

  1794. </B>it is not required to delete a task from the chain. A disabled
    1795. 

  1795. task will not be executed anyway, but you save a few microseconds per
    1796. 

  1796. scheduling pass by deleting it, since it is not even considered for
    1797. 

  1797. execution. 
    1798. 

  1798. </P>
    1799. 

  1799. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">An
    1800. 

  1800. example of proper use of this method would be running some sort of
    1801. 

  1801. <B>initialize</B> task in the chain, and then deleting it from the
    1802. 

  1802. chain since it only needs to run once. 
    1803. 

  1803. </P>
    1804. 

  1804. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1805. 

  1805. </P>
    1806. 

  1806. <P CLASS="western" STYLE="margin-bottom: 0in"><B>void allowSleep(bool
    1807. 

  1807. aState) </B>
    1808. 

  1808. </P>
    1809. 

  1809. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1810. 

  1810. </P>
    1811. 

  1811. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Available
    1812. 

  1812. in API only  if compiled with <FONT FACE="Courier New, monospace">_TASK_TIMECRITICAL</FONT>
    1813. 

  1813. enabled. Controls whether scheduler is allowed (<B>aState =true</B>),
    1814. 

  1814. or not (<B>aState =false</B>) to put processor into IDLE sleep mode
    1815. 

  1815. in case not tasks are scheduled to run.</P>
    1816. 

  1816. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">The
    1817. 

  1817. <B>default</B> behavior of scheduler upon creation is to allow sleep
    1818. 

  1818. mode. 
    1819. 

  1819. </P>
    1820. 

  1820. <P CLASS="western" STYLE="margin-bottom: 0in"><BR><B>void
    1821. 

  1821. enableAll(bool aRecursive= true)</B></P>
    1822. 

  1822. <P CLASS="western" STYLE="margin-bottom: 0in"><B>void disableAll(bool
    1823. 

  1823. aRecursive= true)</B></P>
    1824. 

  1824. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    1825. 

  1825. </P>
    1826. 

  1826. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">enables
    1827. 

  1827. and disables (respectively) all tasks in the chain. Convenient if
    1828. 

  1828. your need to enable/disable majority of the tasks (i.e. disable all
    1829. 

  1829. and then enable one). 
    1830. 

  1830. </P>
    1831. 

  1831. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">If
    1832. 

  1832. support for layered task priority is enabled, supplying <B>aRecursive</B>
    1833. 

  1833. parameter will enable/disable higher priority tasks as well (<B>true</B>,
    1834. 

  1834. default), or tasks only on this priority layer (<B>false</B>). 
    1835. 

  1835. </P>
    1836. 

  1836. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1837. 

  1837. <BR><B>Task&amp; currentTask()<BR></B><BR>
    1838. 

  1838. </P>
    1839. 

  1839. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Returns
    1840. 

  1840. reference to the task, currently executing via <B>execute()</B> loop
    1841. 

  1841. <B>OR </B>for OnEnable and OnDisable methods, reference to the task
    1842. 

  1842. being enabled or disabled. 
    1843. 

  1843. </P>
    1844. 

  1844. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">This
    1845. 

  1845. distinction is important because one task can activate the other, and
    1846. 

  1846. OnEnable should be referring to the task being enabled, not being
    1847. 

  1847. executed. 
    1848. 

  1848. </P>
    1849. 

  1849. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Could
    1850. 

  1850. be used by callback methods to identify which Task actually invoked
    1851. 

  1851. this callback method.</P>
    1852. 

  1852. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    1853. 

  1853. </P>
    1854. 

  1854. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1855. 

  1855. <B>void* currentLts()<BR></B><BR>
    1856. 

  1856. </P>
    1857. 

  1857. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Returns
    1858. 

  1858. pointer to Local Task Storage of the task, currently executing via
    1859. 

  1859. <B>execute()</B> loop <B>OR </B>for OnEnable and OnDisable methods,
    1860. 

  1860. task being enabled or disabled. 
    1861. 

  1861. </P>
    1862. 

  1862. <P CLASS="western" STYLE="margin-bottom: 0in"><BR><B>bool execute()</B></P>
    1863. 

  1863. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    1864. 

  1864. </P>
    1865. 

  1865. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Executes
    1866. 

  1866. one scheduling pass, including (in case of the base priority
    1867. 

  1867. scheduler) end-of-pass sleep. This method is typically placed inside
    1868. 

  1868. the <B>loop()</B> method of the sketch. Since <B>execute</B> exits
    1869. 

  1869. after every pass, you can put additional statements after <B>execute</B>
    1870. 

  1870. inside the <B>loop().</B></P>
    1871. 

  1871. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1872. 

  1872. </P>
    1873. 

  1873. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><B>If
    1874. 

  1874. layered task prioritization is enabled, all higher priority tasks
    1875. 

  1875. will be evaluated and invoked by the base <FONT FACE="Courier New, monospace">execute()</FONT>
    1876. 

  1876. method. There is no need to call <FONT FACE="Courier New, monospace">execute()</FONT>
    1877. 

  1877. of the higher priority schedulers explicitly. </B>
    1878. 

  1878. </P>
    1879. 

  1879. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1880. 

  1880. </P>
    1881. 

  1881. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">Generally,
    1882. 

  1882. base priority execute will perform the following steps:</P>
    1883. 

  1883. <OL>
    1884. 

  1884. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in">Call higher
    1885. 

  1885. 	priority scheduler’s execute method, if provided.</P>
    1886. 

  1886. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in">Ignore task
    1887. 

  1887. 	completely if it is disabled.</P>
    1888. 

  1888. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in">Disable task if it
    1889. 

  1889. 	ran out of iterations (calling OnDisable, if necessary).</P>
    1890. 

  1890. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in">Check if task is
    1891. 

  1891. 	waiting on a StatusRequest object, and make appropriate scheduling
    1892. 

  1892. 	arrangements</P>
    1893. 

  1893. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in">Perform necessary
    1894. 

  1894. 	timing calculations</P>
    1895. 

  1895. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in">Invoke task's
    1896. 

  1896. 	callback method, if it is time to do so, and one is provided. 
    1897. 

  1897. 	</P>
    1898. 

  1898. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in">Put
    1899. 

  1899. 	microcontroller to sleep (if requested and supported) if none of the
    1900. 

  1900. 	tasks were invoked. 
    1901. 

  1901. 	</P>
    1902. 

  1902. </OL>
    1903. 

  1903. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1904. 

  1904. </P>
    1905. 

  1905. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><B>Please
    1906. 

  1906. NOTE:</B> schedule-related calculations are performed prior to task's
    1907. 

  1907. callback method invocation. This allows tasks to manipulate their
    1908. 

  1908. runtime parameters (like execution interval) directly.</P>
    1909. 

  1909. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1910. 

  1910. </P>
    1911. 

  1911. <P CLASS="western" STYLE="margin-bottom: 0in"><B>bool isOverrun()</B></P>
    1912. 

  1912. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">If
    1913. 

  1913. library is compiled with <FONT FACE="Courier New, monospace">_TASK_TIMECRITICAL</FONT>
    1914. 

  1914. enabled, this method returns <B>true</B> if currently invoked task
    1915. 

  1915. has overrun its scheduled start time when it was invoked. Returns
    1916. 

  1916. <B>false</B> if task has been invoked according to schedule.</P>
    1917. 

  1917. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1918. 

  1918. </P>
    1919. 

  1919. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1920. 

  1920. <BR>
    1921. 

  1921. </P>
    1922. 

  1922. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1923. 

  1923. <B>TASK PRIORITY:</B></P>
    1924. 

  1924. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1925. 

  1925. <BR>
    1926. 

  1926. </P>
    1927. 

  1927. <P CLASS="western" STYLE="margin-bottom: 0in"><B>void
    1928. 

  1928. setHighPriorityScheduler(Scheduler* aScheduler);</B><BR><BR>
    1929. 

  1929. </P>
    1930. 

  1930. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">If
    1931. 

  1931. library is compiled with <FONT FACE="Courier New, monospace">_TASK_PRIORITY
    1932. 

  1932. </FONT>enabled, this method associates current scheduler with a
    1933. 

  1933. higher priority scheduler. 
    1934. 

  1934. </P>
    1935. 

  1935. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><B>NOTE:
    1936. 

  1936. </B>Only one <B>execute() </B>method needs to be explicitly called in
    1937. 

  1937. the main <B>loop(). </B>That is the execute method of <B>base</B>
    1938. 

  1938. priority scheduler. All higher priority schedulers are called by the
    1939. 

  1939. base priority scheduler.</P>
    1940. 

  1940. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1941. 

  1941. </P>
    1942. 

  1942. <P CLASS="western" STYLE="margin-bottom: 0in"><B>static Scheduler&amp;
    1943. 

  1943. currentScheduler()</B></P>
    1944. 

  1944. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">If
    1945. 

  1945. library is compiled with <FONT FACE="Courier New, monospace">_TASK_PRIORITY
    1946. 

  1946. </FONT>enabled, this method returns reference to a scheduler, which
    1947. 

  1947. invoked current task. 
    1948. 

  1948. </P>
    1949. 

  1949. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    1950. 

  1950. </P>
    1951. 

  1951. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><B>NOTE:
    1952. 

  1952. Please refer to examples 11 and 12 for illustration of Task Priority
    1953. 

  1953. functionality</B></P>
    1954. 

  1954. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1955. 

  1955. <BR>
    1956. 

  1956. </P>
    1957. 

  1957. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1958. 

  1958. <BR>
    1959. 

  1959. </P>
    1960. 

  1960. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1961. 

  1961. <BR>
    1962. 

  1962. </P>
    1963. 

  1963. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1964. 

  1964. <B>CONSTANTS:</B></P>
    1965. 

  1965. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    1966. 

  1966. <BR>
    1967. 

  1967. </P>
    1968. 

  1968. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in; page-break-after: avoid">
    1969. 

  1969. <B>TASK_SECOND	(1000)</B></P>
    1970. 

  1970. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in">Task
    1971. 

  1971. interval of 1 second</P>
    1972. 

  1972. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><BR>
    1973. 

  1973. </P>
    1974. 

  1974. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in; page-break-after: avoid">
    1975. 

  1975. <B>TASK_MINUTE	(60000)</B></P>
    1976. 

  1976. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in">Task
    1977. 

  1977. interval of 1 minute</P>
    1978. 

  1978. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><BR>
    1979. 

  1979. </P>
    1980. 

  1980. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in; page-break-after: avoid">
    1981. 

  1981. <B>TASK_HOUR		(3600000)</B></P>
    1982. 

  1982. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in">Task
    1983. 

  1983. interval of 1 hour</P>
    1984. 

  1984. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in; page-break-after: avoid">
    1985. 

  1985. <B>TASK_FOREVER	(-1)</B></P>
    1986. 

  1986. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in">Task
    1987. 

  1987. number of iterations for infinite number of iterations</P>
    1988. 

  1988. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><BR>
    1989. 

  1989. </P>
    1990. 

  1990. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in; page-break-after: avoid">
    1991. 

  1991. <B>TASK_ONCE		(1)</B></P>
    1992. 

  1992. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in">Task
    1993. 

  1993. single iteration</P>
    1994. 

  1994. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><BR>
    1995. 

  1995. </P>
    1996. 

  1996. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in; page-break-after: avoid">
    1997. 

  1997. <B>TASK_IMMEDIATE	(0)</B></P>
    1998. 

  1998. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in">Task
    1999. 

  1999. interval for immediate execution</P>
    2000. 

  2000. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2001. 

  2001. </P>
    2002. 

  2002. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2003. 

  2003. </P>
    2004. 

  2004. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-before: always; page-break-after: avoid">
    2005. 

  2005. <B>IMPLEMENTATION SCENARIOS AND IDEAS:</B></P>
    2006. 

  2006. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    2007. 

  2007. <BR>
    2008. 

  2008. </P>
    2009. 

  2009. <OL>
    2010. 

  2010. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    2011. 

  2011. 	<B>EVENT DRIVEN PROGRAMMING</B></P>
    2012. 

  2012. </OL>
    2013. 

  2013. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    2014. 

  2014. <BR>
    2015. 

  2015. </P>
    2016. 

  2016. <P CLASS="western" STYLE="margin-bottom: 0in">Each of the processes
    2017. 

  2017. of your application becomes a separate and distinct programming area,
    2018. 

  2018. which may or may not interact and control each other. 
    2019. 

  2019. </P>
    2020. 

  2020. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    2021. 

  2021. </P>
    2022. 

  2022. <P CLASS="western" STYLE="margin-bottom: 0in">Example: 
    2023. 

  2023. </P>
    2024. 

  2024. <P CLASS="western" STYLE="margin-bottom: 0in">In a plant watering
    2025. 

  2025. system you need to measure soil humidity, control pump and display
    2026. 

  2026. the results</P>
    2027. 

  2027. <P CLASS="western" STYLE="margin-bottom: 0in">Each of the areas
    2028. 

  2028. becomes a task:</P>
    2029. 

  2029. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    2030. 

  2030. </P>
    2031. 

  2031. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>Task
    2032. 

  2032. <B>tMeasure</B> (TMEASURE_INTERVAL*SECOND, TASK_FOREVER,
    2033. 

  2033. &amp;measureCallback);<BR>Task <B>tWater</B>  
    2034. 

  2034. (TWATER_INTERVAL*SECOND, RETRIES, &amp;waterCallback);<BR>Task
    2035. 

  2035. <B>tDisplay</B> (TDISPLAY_INTERVAL*SECOND, TASK_FOREVER,
    2036. 

  2036. &amp;displayCallback); <BR></FONT></FONT><BR>
    2037. 

  2037. </P>
    2038. 

  2038. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>Scheduler
    2039. 

  2039. </FONT></FONT><FONT FACE="Courier New, monospace"><FONT SIZE=2><B>taskManager</B></FONT></FONT><FONT FACE="Courier New, monospace"><FONT SIZE=2>;</FONT></FONT><BR><BR>
    2040. 

  2040. </P>
    2041. 

  2041. <P CLASS="western" STYLE="margin-bottom: 0in">Further, once you turn
    2042. 

  2042. on the pump, you keep it running for TWATER_INTERVAL interval and
    2043. 

  2043. then turn it off. Turning off a pump is also a task which only needs
    2044. 

  2044. to run once for every time the pump is turned on:</P>
    2045. 

  2045. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    2046. 

  2046. </P>
    2047. 

  2047. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>Task
    2048. 

  2048. </FONT></FONT><FONT FACE="Courier New, monospace"><FONT SIZE=2><B>tWaterOff</B></FONT></FONT><FONT FACE="Courier New, monospace"><FONT SIZE=2>
    2049. 

  2049. (WATERTIME*SECOND, TASK_ONCE,</FONT></FONT><FONT FACE="Courier New, monospace">
    2050. 

  2050. &amp;waterOffCallback);</FONT><BR><BR>
    2051. 

  2051. </P>
    2052. 

  2052. <P CLASS="western" STYLE="margin-bottom: 0in">Example of the callback
    2053. 

  2053. method:</P>
    2054. 

  2054. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    2055. 

  2055. </P>
    2056. 

  2056. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>void
    2057. 

  2057. waterOffCallback() {<BR>    motorOff();<BR>   
    2058. 

  2058. tWater.enableDelayed();<BR>}</FONT></FONT></P>
    2059. 

  2059. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2060. 

  2060. </P>
    2061. 

  2061. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>or</FONT></FONT></P>
    2062. 

  2062. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2063. 

  2063. </P>
    2064. 

  2064. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>void
    2065. 

  2065. waterCallback() {<BR>    if (tWater.getIterations()) {</FONT></FONT></P>
    2066. 

  2066. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>//
    2067. 

  2067. If this is not the last iteration = turn the pump on<BR>     
    2068. 

  2068. motorOn();<BR>      tWaterOff.set(parameters.watertime * TASK_SECOND,
    2069. 

  2069. TASK_ONCE, &amp;waterOffCallback);<BR>     
    2070. 

  2070. tWaterOff.enableDelayed();<BR>      return;<BR>    }</FONT></FONT></P>
    2071. 

  2071. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>//
    2072. 

  2072. We could not reach target humidity – something is wrong<BR>   
    2073. 

  2073. motorOff;<BR>    taskManager.disableAll();<BR>    tError.enable();<BR>}</FONT></FONT></P>
    2074. 

  2074. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    2075. 

  2075. </P>
    2076. 

  2076. <P CLASS="western" STYLE="margin-bottom: 0in"><FONT FACE="Times New Roman, serif">Your
    2077. 

  2077. sample <B>setup</B>() and <B>loop</B>() (partially) are as follows. </FONT>
    2078. 

  2078. </P>
    2079. 

  2079. <P CLASS="western" STYLE="margin-bottom: 0in"><FONT FACE="Times New Roman, serif"><B>Note:
    2080. 

  2080. </B>please note that tWater is <B>not</B> activated during setup().
    2081. 

  2081. It is activated by tMeasure callback once the watering conditions are
    2082. 

  2082. met. </FONT>
    2083. 

  2083. </P>
    2084. 

  2084. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    2085. 

  2085. </P>
    2086. 

  2086. <P CLASS="western" STYLE="margin-bottom: 0in"><FONT SIZE=2><FONT FACE="Times New Roman, serif">	void
    2087. 

  2087. </FONT><FONT FACE="Courier New, monospace">setup()</FONT></FONT></P>
    2088. 

  2088. <P CLASS="western" STYLE="margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>	
    2089. 

  2089.  ...</FONT></FONT></P>
    2090. 

  2090. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2091. 

  2091. <FONT SIZE=2><FONT FACE="Courier New, monospace">tWater.setIterations(parameters.retries);<BR>
    2092. 

  2092.  tWaterOff.setInterval(parameters.watertime * SECOND);<BR><BR><BR> 
    2093. 

  2093. taskManager.init();<BR>  taskManager.addTask(tMeasure);<BR> 
    2094. 

  2094. taskManager.addTask(tDisplay);<BR>  taskManager.addTask(tWater);<BR> 
    2095. 

  2095. taskManager.addTask(tWaterOff);<BR>  <BR>  tMeasure.enable();<BR> 
    2096. 

  2096. tDisplay.enable();<BR><BR>  currentHumidity =
    2097. 

  2097. measureHumidity();<BR>}<BR><BR><BR>void loop ()<BR>{<BR> 
    2098. 

  2098. taskManager.execute();<BR>}</FONT><FONT FACE="Times New Roman, serif"><BR></FONT></FONT><BR>
    2099. 

  2099. </P>
    2100. 

  2100. <OL START=2>
    2101. 

  2101. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    2102. 

  2102. 	“<FONT FACE="Times New Roman, serif"><B>NATIVE” SUPPORT FOR
    2103. 

  2103. 	FINITE STATE MACHINE</B></FONT></P>
    2104. 

  2104. </OL>
    2105. 

  2105. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    2106. 

  2106. <BR>
    2107. 

  2107. </P>
    2108. 

  2108. <P CLASS="western" STYLE="margin-bottom: 0in"><FONT FACE="Times New Roman, serif">Define
    2109. 

  2109. “states” as callback method or methods. Each callback method
    2110. 

  2110. executes activities specific to a “state” and then “transitions”
    2111. 

  2111. to the next state by assigning next callback method to the task. </FONT>
    2112. 

  2112. </P>
    2113. 

  2113. <P CLASS="western" STYLE="margin-bottom: 0in"><FONT FACE="Times New Roman, serif">Transition
    2114. 

  2114. from one state to the next is achieved by setting next callback
    2115. 

  2115. method at the end of preceding one. </FONT>
    2116. 

  2116. </P>
    2117. 

  2117. <P CLASS="western" STYLE="margin-bottom: 0in"><FONT FACE="Times New Roman, serif"><B>Note:
    2118. 

  2118. </B>do not call the next callback method explicitly. Yield to the
    2119. 

  2119. scheduler, and let the scheduler take care of next iteration during
    2120. 

  2120. the next pass. (Thus giving other tasks change to run their callback
    2121. 

  2121. methods). </FONT>
    2122. 

  2122. </P>
    2123. 

  2123. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    2124. 

  2124. </P>
    2125. 

  2125. <P CLASS="western" STYLE="margin-bottom: 0in"><FONT FACE="Times New Roman, serif">Example:
    2126. 

  2126. Blinking LED 2 times a second could be achieved this way</FONT></P>
    2127. 

  2127. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2128. 

  2128. </P>
    2129. 

  2129. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>Scheduler
    2130. 

  2130. ts;</FONT></FONT></P>
    2131. 

  2131. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>Task
    2132. 

  2132. tLedBlinker (500, TASK_FOREVER, &amp;ledOnCallback, &amp;ts, true);</FONT></FONT></P>
    2133. 

  2133. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2134. 

  2134. </P>
    2135. 

  2135. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>void
    2136. 

  2136.  ledOnCallback() {</FONT></FONT></P>
    2137. 

  2137. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>	turnLedOn();</FONT></FONT></P>
    2138. 

  2138. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>	tLedBlinker.setCallback(&amp;ledOffCallback);</FONT></FONT></P>
    2139. 

  2139. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>}</FONT></FONT></P>
    2140. 

  2140. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2141. 

  2141. </P>
    2142. 

  2142. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>void
    2143. 

  2143.  ledOffCallback() {</FONT></FONT></P>
    2144. 

  2144. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>	turnLedOff();</FONT></FONT></P>
    2145. 

  2145. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>	tLedBlinker.setCallback(&amp;ledOnCallback);</FONT></FONT></P>
    2146. 

  2146. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>}</FONT></FONT></P>
    2147. 

  2147. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2148. 

  2148. </P>
    2149. 

  2149. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>setup()
    2150. 

  2150. {</FONT></FONT></P>
    2151. 

  2151. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>}</FONT></FONT></P>
    2152. 

  2152. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2153. 

  2153. </P>
    2154. 

  2154. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>loop
    2155. 

  2155. () {</FONT></FONT></P>
    2156. 

  2156. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>	ts.execute();</FONT></FONT></P>
    2157. 

  2157. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>}</FONT></FONT><FONT FACE="Times New Roman, serif"><BR></FONT><BR>
    2158. 

  2158. </P>
    2159. 

  2159. <P CLASS="western" STYLE="margin-bottom: 0in"><FONT FACE="Times New Roman, serif">Obviously
    2160. 

  2160. the example is simple, but gives the idea of how the tasks could be
    2161. 

  2161. used to go through states.</FONT></P>
    2162. 

  2162. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    2163. 

  2163. </P>
    2164. 

  2164. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    2165. 

  2165. </P>
    2166. 

  2166. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    2167. 

  2167. </P>
    2168. 

  2168. <OL START=3>
    2169. 

  2169. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    2170. 

  2170. 	<FONT FACE="Times New Roman, serif"><B>MULTIPLE POSSIBLE CALLBACKS
    2171. 

  2171. 	FOR TASK</B></FONT></P>
    2172. 

  2172. </OL>
    2173. 

  2173. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    2174. 

  2174. <BR>
    2175. 

  2175. </P>
    2176. 

  2176. <P CLASS="western" STYLE="margin-bottom: 0in"><FONT FACE="Times New Roman, serif">There
    2177. 

  2177. may be a need to select an option for callback method based on
    2178. 

  2178. certain criteria, or randomly. </FONT>
    2179. 

  2179. </P>
    2180. 

  2180. <P CLASS="western" STYLE="margin-bottom: 0in"><FONT FACE="Times New Roman, serif">You
    2181. 

  2181. can achieve that by defining an array of callback method pointers and
    2182. 

  2182. selecting one based on the criteria you need. </FONT>
    2183. 

  2183. </P>
    2184. 

  2184. <P CLASS="western" STYLE="margin-bottom: 0in"><FONT FACE="Times New Roman, serif">Example:
    2185. 

  2185. when a robot detects an obstacle, it may go left, right backwards,
    2186. 

  2186. etc. Each of the “directions” or “behaviors” are represented
    2187. 

  2187. by a different callback methods. </FONT>
    2188. 

  2188. </P>
    2189. 

  2189. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    2190. 

  2190. </P>
    2191. 

  2191. <P CLASS="western" STYLE="margin-bottom: 0in"><FONT FACE="Times New Roman, serif">Another
    2192. 

  2192. example of using multiple callbacks:</FONT></P>
    2193. 

  2193. <P CLASS="western" STYLE="margin-bottom: 0in"><FONT FACE="Times New Roman, serif">You
    2194. 

  2194. may need to “initialize” variables for a particular task.</FONT></P>
    2195. 

  2195. <P CLASS="western" STYLE="margin-bottom: 0in"><FONT FACE="Times New Roman, serif">In
    2196. 

  2196. this case, define a tasks with two callbacks:</FONT></P>
    2197. 

  2197. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    2198. 

  2198. </P>
    2199. 

  2199. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>Task
    2200. 

  2200. <B>tWork</B> (T_INTERVAL, TASK_FOREVER, &amp;workCallbackInit);</FONT></FONT></P>
    2201. 

  2201. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">…</P>
    2202. 

  2202. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2203. 

  2203. </P>
    2204. 

  2204. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>void
    2205. 

  2205.  workCallbackInit() {</FONT></FONT></P>
    2206. 

  2206. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>	//
    2207. 

  2207. do your initializationstuff here</FONT></FONT></P>
    2208. 

  2208. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>	</FONT></FONT></P>
    2209. 

  2209. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>	//
    2210. 

  2210. finally assigne the main callback method </FONT></FONT>
    2211. 

  2211. </P>
    2212. 

  2212. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>	tWork.setCallback(&amp;workCallback);</FONT></FONT></P>
    2213. 

  2213. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>}</FONT></FONT></P>
    2214. 

  2214. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2215. 

  2215. </P>
    2216. 

  2216. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>void
    2217. 

  2217. workCallback() {</FONT></FONT></P>
    2218. 

  2218. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>	//
    2219. 

  2219. main callback method</FONT></FONT></P>
    2220. 

  2220. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>	…</FONT></FONT></P>
    2221. 

  2221. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>}</FONT></FONT></P>
    2222. 

  2222. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    2223. 

  2223. </P>
    2224. 

  2224. <P CLASS="western" STYLE="margin-bottom: 0in"><FONT FACE="Times New Roman, serif">The
    2225. 

  2225. task will initialize during first execution pass and switch to
    2226. 

  2226. “regular” callback execution starting with second pass. There is
    2227. 

  2227. a delay between first and second passes of the task (scheduling
    2228. 

  2228. period, if defined). In order to execute the second pass immediately
    2229. 

  2229. after initialization first pass, change the above code like this:</FONT></P>
    2230. 

  2230. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    2231. 

  2231. </P>
    2232. 

  2232. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>void
    2233. 

  2233.  workCallbackInit() {</FONT></FONT></P>
    2234. 

  2234. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>	//
    2235. 

  2235. do your initializationstuff here</FONT></FONT></P>
    2236. 

  2236. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>	</FONT></FONT></P>
    2237. 

  2237. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>	//
    2238. 

  2238. finally assigne the main callback method </FONT></FONT>
    2239. 

  2239. </P>
    2240. 

  2240. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>	tWork.setCallback(&amp;workCallback);</FONT></FONT></P>
    2241. 

  2241. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>	tWork.enable();</FONT></FONT></P>
    2242. 

  2242. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>}</FONT></FONT></P>
    2243. 

  2243. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    2244. 

  2244. </P>
    2245. 

  2245. <P CLASS="western" STYLE="margin-bottom: 0in"><FONT FACE="Times New Roman, serif">The
    2246. 

  2246. task will run initialization first, then immediately second pass, and
    2247. 

  2247. then switch to processing at regular intervals starting with a third
    2248. 

  2248. pass. </FONT>
    2249. 

  2249. </P>
    2250. 

  2250. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    2251. 

  2251. </P>
    2252. 

  2252. <OL START=3>
    2253. 

  2253. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    2254. 

  2254. 	<FONT FACE="Times New Roman, serif"><B>INTERRUP-DRIVEN EXECUTION
    2255. 

  2255. 	SUPPORT </B></FONT>
    2256. 

  2256. 	</P>
    2257. 

  2257. </OL>
    2258. 

  2258. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    2259. 

  2259. <BR>
    2260. 

  2260. </P>
    2261. 

  2261. <P CLASS="western" STYLE="margin-bottom: 0in"><FONT FACE="Times New Roman, serif">In
    2262. 

  2262. case of interrupt-driven program flow, tasks could be scheduled to
    2263. 

  2263. run once to request asynchronous execution (request), and then
    2264. 

  2264. re-enabled (restarted) again with a different callback method to
    2265. 

  2265. process the results. </FONT>
    2266. 

  2266. </P>
    2267. 

  2267. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    2268. 

  2268. </P>
    2269. 

  2269. <P CLASS="western" STYLE="margin-bottom: 0in"><FONT FACE="Times New Roman, serif"><B>Example</B>:
    2270. 

  2270. event driven distance calculation for ultrasonic pulses. EchoPin #6
    2271. 

  2271. triggers pin change interrupts on rising and falling edges to
    2272. 

  2272. determine the length of ultrasonic pulse.</FONT></P>
    2273. 

  2273. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    2274. 

  2274. </P>
    2275. 

  2275. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>#include
    2276. 

  2276. &lt;DirectIO.h&gt;<BR>#include &lt;TaskScheduler.h&gt;<BR>#include
    2277. 

  2277. &lt;PinChangeInt.h&gt;<BR><BR><BR>#define  TRIGGERPIN 5<BR>#define 
    2278. 

  2278. ECHOPIN    6<BR><BR>Output&lt;TRIGGERPIN&gt; 
    2279. 

  2279. pTrigger;<BR>Input&lt;ECHOPIN&gt;      pEcho;<BR><BR>Scheduler
    2280. 

  2280. r;<BR><BR>Task  tMeasure(TASK_SECOND, TASK_FOREVER, &amp;measureCallback,
    2281. 

  2281. &amp;r, true);<BR>Task  tDisplay(TASK_SECOND, TASK_FOREVER,
    2282. 

  2282. &amp;displayCallback, &amp;r, true);<BR>Task  tPing(TASK_IMMEDIATE,
    2283. 

  2283. TASK_ONCE, &amp;pingCalcCallback, &amp;r, false);<BR><BR><BR>volatile
    2284. 

  2284. bool pulseBusy = false;<BR>volatile bool pulseTimeout =
    2285. 

  2285. false;<BR>volatile unsigned long pulseStart = 0;<BR>volatile unsigned
    2286. 

  2286. long pulseStop = 0;<BR>volatile unsigned long pingDistance =
    2287. 

  2287. 0;<BR><BR><BR>void pingTrigger(unsigned long aTimeout) {<BR>  if
    2288. 

  2288. (pulseBusy) return;  // do not trigger if in the middle of a pulse<BR>
    2289. 

  2289.  if (pEcho == HIGH) return; // do not trigger if ECHO pin is high<BR>
    2290. 

  2290.  <BR>  pulseBusy = true;<BR>  pulseTimeout = false;</FONT></FONT></P>
    2291. 

  2291. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2><BR>
    2292. 

  2292.  pTrigger = LOW;<BR>  delayMicroseconds(4);<BR>  pTrigger = HIGH;<BR><BR>
    2293. 

  2293.  tPing.setInterval (aTimeout);<BR><BR>  delayMicroseconds(10);<BR> 
    2294. 

  2294. pTrigger = LOW; <BR></FONT></FONT><BR>
    2295. 

  2295. </P>
    2296. 

  2296. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2297. 

  2297. <FONT FACE="Courier New, monospace"><FONT SIZE=2>tPing.restartDelayed();
    2298. 

  2298. // timeout countdown starts now<BR></FONT></FONT><BR>
    2299. 

  2299. </P>
    2300. 

  2300. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>//
    2301. 

  2301. will start the pulse clock on the rising edge of ECHO pin</FONT></FONT></P>
    2302. 

  2302. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2303. 

  2303. <FONT FACE="Courier New, monospace"><FONT SIZE=2>PCintPort::attachInterrupt(ECHOPIN,
    2304. 

  2304. &amp;pingStartClock, RISING); <BR>}<BR><BR></FONT></FONT><BR>
    2305. 

  2305. </P>
    2306. 

  2306. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>//
    2307. 

  2307. Start clock on the <B>rising</B> edge of the ultrasonic pulse<BR>void
    2308. 

  2308. pingStartClock() {<BR>  pulseStart = micros();<BR> 
    2309. 

  2309. PCintPort::detachInterrupt(ECHOPIN); // not sure this is necessary<BR>
    2310. 

  2310.  PCintPort::attachInterrupt(ECHOPIN, &amp;pingStopClock, FALLING); <BR>
    2311. 

  2311.  tPing.restartDelayed();<BR>}<BR><BR>// Stop clock on the <B>falling</B>
    2312. 

  2312. edge of the ultrasonic pulse<BR>void pingStopClock() {<BR>  pulseStop
    2313. 

  2313. = micros();<BR>  PcintPort::detachInterrupt(ECHOPIN);</FONT></FONT></P>
    2314. 

  2314. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2315. 

  2315. <FONT FACE="Courier New, monospace"><FONT SIZE=2>pingDistance =
    2316. 

  2316. pulseStop - pulseStart;<BR>  pulseBusy = false;<BR>  tPing.disable();
    2317. 

  2317. // disable timeout<BR>}<BR></FONT></FONT><BR>
    2318. 

  2318. </P>
    2319. 

  2319. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>//
    2320. 

  2320. Stop clock because of the timeout – the wave did not return<BR>void
    2321. 

  2321. pingCalcCallback() {<BR>  if (pulseBusy) {<BR>    pingStopClock();<BR>
    2322. 

  2322.  }<BR>  pulseTimeout = true;<BR>}<BR><BR><BR><BR>// Initial measure
    2323. 

  2323. callback sets the trigger<BR>void measureCallback() {<BR>  if
    2324. 

  2324. (pulseBusy) {  // already measuring, try again<BR>   
    2325. 

  2325. tMeasure.enable();<BR>    return;<BR>  }<BR>  pingTrigger(30); // 30
    2326. 

  2326. milliseconds or max range of ~5.1 meters<BR> 
    2327. 

  2327. tMeasure.setCallback(&amp;measureCallbackWait);<BR>}<BR></FONT></FONT><BR>
    2328. 

  2328. </P>
    2329. 

  2329. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>//
    2330. 

  2330. Wait for the measurement to <BR>void measureCallbackWait() {<BR>  if
    2331. 

  2331. (pulseBusy) return;<BR>  tMeasure.setCallback(&amp;measureCallback); 
    2332. 

  2332. <BR>}<BR><BR><BR>bool state = true;<BR><BR>void displayCallback() {<BR>
    2333. 

  2333.  char d[256];<BR>   <BR>  unsigned long cm = pingDistance * 17 / 100;
    2334. 

  2334. // cm<BR>  <BR>  snprintf(d, 256, &quot;pulseStart =
    2335. 

  2335. %8lu\tpulseStop=%8lu\tdistance, cm=%8lu&quot;, pulseStart, pulseStop,
    2336. 

  2336. cm);<BR>  Serial.println(d);<BR>  <BR>}<BR><BR>void setup() {<BR>  //
    2337. 

  2337. put your setup code here, to run once:<BR>  <BR> 
    2338. 

  2338. Serial.begin(115200);<BR>  <BR><BR>  pTrigger = LOW;<BR>  pEcho =
    2339. 

  2339. LOW;<BR>  <BR>}<BR><BR>void loop() {<BR>  // put your main code here,
    2340. 

  2340. to run repeatedly:<BR>  r.execute();<BR>}<BR></FONT></FONT><BR>
    2341. 

  2341. </P>
    2342. 

  2342. <OL START=3>
    2343. 

  2343. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    2344. 

  2344. 	<FONT FACE="Times New Roman, serif"><B>USING ONENABLE AND ONDISBALE
    2345. 

  2345. 	METHODS </B></FONT>
    2346. 

  2346. 	</P>
    2347. 

  2347. </OL>
    2348. 

  2348. <P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    2349. 

  2349. <BR>
    2350. 

  2350. </P>
    2351. 

  2351. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Times New Roman, serif">Consider
    2352. 

  2352. a task to flash onboard LED for 5 seconds with random frequency. Task
    2353. 

  2353. should be repeated every 30 seconds indefinitely. Since frequency is
    2354. 

  2354. random, there are two challenges:</FONT></P>
    2355. 

  2355. <OL START=3>
    2356. 

  2356. 	<OL>
    2357. 

  2357. 		<LI><P CLASS="western" STYLE="margin-bottom: 0in"><FONT FACE="Times New Roman, serif">We
    2358. 

  2358. 		need to make sure LED is turned OFF at the last iteration</FONT></P>
    2359. 

  2359. 		<LI><P CLASS="western" STYLE="margin-bottom: 0in"><FONT FACE="Times New Roman, serif">We
    2360. 

  2360. 		need to calculate random frequency every time</FONT></P>
    2361. 

  2361. 	</OL>
    2362. 

  2362. </OL>
    2363. 

  2363. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2364. 

  2364. </P>
    2365. 

  2365. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Times New Roman, serif">Below
    2366. 

  2366. is the implementation using TaskScheduler </FONT>
    2367. 

  2367. </P>
    2368. 

  2368. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2369. 

  2369. </P>
    2370. 

  2370. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2><BR></FONT></FONT><BR>
    2371. 

  2371. </P>
    2372. 

  2372. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>#define
    2373. 

  2373. _TASK_SLEEP_ON_IDLE_RUN</FONT></FONT></P>
    2374. 

  2374. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>#include
    2375. 

  2375. &lt;TaskScheduler.h&gt;</FONT></FONT></P>
    2376. 

  2376. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2377. 

  2377. </P>
    2378. 

  2378. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>#define
    2379. 

  2379.  LEDPIN    13</FONT></FONT></P>
    2380. 

  2380. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2381. 

  2381. </P>
    2382. 

  2382. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2383. 

  2383. </P>
    2384. 

  2384. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>Scheduler
    2385. 

  2385. ts;</FONT></FONT></P>
    2386. 

  2386. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2387. 

  2387. </P>
    2388. 

  2388. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>Task
    2389. 

  2389. tWrapper(30000, TASK_FOREVER, &amp;WrapperCallback, &amp;ts, true);</FONT></FONT></P>
    2390. 

  2390. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>Task
    2391. 

  2391. tBlink(5000, TASK_ONCE, NULL, &amp;ts, false, &amp;BlinkOnEnable,
    2392. 

  2392. &amp;BlinkOnDisable);</FONT></FONT></P>
    2393. 

  2393. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>Task
    2394. 

  2394. tLED(TASK_IMMEDIATE, TASK_FOREVER, NULL, &amp;ts, false, NULL,
    2395. 

  2395. &amp;LEDOff);</FONT></FONT></P>
    2396. 

  2396. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2397. 

  2397. </P>
    2398. 

  2398. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>void
    2399. 

  2399. WrapperCallback() {</FONT></FONT></P>
    2400. 

  2400. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2401. 

  2401. <FONT FACE="Courier New, monospace"><FONT SIZE=2>Serial.println(&quot;In
    2402. 

  2402. WrapperCallback&quot;);</FONT></FONT></P>
    2403. 

  2403. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2404. 

  2404. <FONT FACE="Courier New, monospace"><FONT SIZE=2>tBlink.restartDelayed();
    2405. 

  2405.   // LED blinking  is initiated </FONT></FONT>
    2406. 

  2406. </P>
    2407. 

  2407. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    2408. 

  2408.             <FONT FACE="Courier New, monospace"><FONT SIZE=2>//every
    2409. 

  2409. 30 seconds for 5 seconds</FONT></FONT></P>
    2410. 

  2410. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>}</FONT></FONT></P>
    2411. 

  2411. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2412. 

  2412. </P>
    2413. 

  2413. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2414. 

  2414. </P>
    2415. 

  2415. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>//
    2416. 

  2416. Upon being enabled, tBlink will define the parameters</FONT></FONT></P>
    2417. 

  2417. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>//
    2418. 

  2418. and enable LED blinking task, which actually controls</FONT></FONT></P>
    2419. 

  2419. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>//
    2420. 

  2420. the hardware (LED in this example)</FONT></FONT></P>
    2421. 

  2421. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>bool
    2422. 

  2422. BlinkOnEnable() {</FONT></FONT></P>
    2423. 

  2423. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2424. 

  2424. <FONT FACE="Courier New, monospace"><FONT SIZE=2>Serial.println(&quot;In
    2425. 

  2425. BlinkOnEnable&quot;);</FONT></FONT></P>
    2426. 

  2426. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2427. 

  2427. <FONT FACE="Courier New, monospace"><FONT SIZE=2>tLED.setInterval(
    2428. 

  2428. 500 + random(501) );</FONT></FONT></P>
    2429. 

  2429. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2430. 

  2430. <FONT FACE="Courier New, monospace"><FONT SIZE=2>tLED.setCallback(
    2431. 

  2431. &amp;LEDOn);</FONT></FONT></P>
    2432. 

  2432. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2433. 

  2433. <FONT FACE="Courier New, monospace"><FONT SIZE=2>tLED.enable();</FONT></FONT></P>
    2434. 

  2434. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2435. 

  2435. </P>
    2436. 

  2436. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2437. 

  2437. <FONT FACE="Courier New, monospace"><FONT SIZE=2>return true;  //
    2438. 

  2438. Task should be enabled</FONT></FONT></P>
    2439. 

  2439. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>}</FONT></FONT></P>
    2440. 

  2440. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2441. 

  2441. </P>
    2442. 

  2442. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>//
    2443. 

  2443. tBlink does not really need a callback method</FONT></FONT></P>
    2444. 

  2444. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>//
    2445. 

  2445. since it just waits for 5 seconds for the first </FONT></FONT>
    2446. 

  2446. </P>
    2447. 

  2447. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>//
    2448. 

  2448. and only iteration to occur. Once the iteration</FONT></FONT></P>
    2449. 

  2449. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>//
    2450. 

  2450. takes place, tBlink is disabled by the Scheduler, </FONT></FONT>
    2451. 

  2451. </P>
    2452. 

  2452. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>//
    2453. 

  2453. thus executing its OnDisable method below.</FONT></FONT></P>
    2454. 

  2454. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2455. 

  2455. </P>
    2456. 

  2456. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>void
    2457. 

  2457. BlinkOnDisable() {</FONT></FONT></P>
    2458. 

  2458. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2459. 

  2459. <FONT FACE="Courier New, monospace"><FONT SIZE=2>Serial.println(&quot;In
    2460. 

  2460. BlinkOnDisable&quot;);</FONT></FONT></P>
    2461. 

  2461. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2462. 

  2462. <FONT FACE="Courier New, monospace"><FONT SIZE=2>tLED.disable();</FONT></FONT></P>
    2463. 

  2463. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>}</FONT></FONT></P>
    2464. 

  2464. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2465. 

  2465. </P>
    2466. 

  2466. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>void
    2467. 

  2467. LEDOn () {</FONT></FONT></P>
    2468. 

  2468. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2469. 

  2469. <FONT FACE="Courier New, monospace"><FONT SIZE=2>Serial.println(&quot;In
    2470. 

  2470. LEDOn&quot;);</FONT></FONT></P>
    2471. 

  2471. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2472. 

  2472. <FONT FACE="Courier New, monospace"><FONT SIZE=2>digitalWrite(LEDPIN,
    2473. 

  2473. HIGH);</FONT></FONT></P>
    2474. 

  2474. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2475. 

  2475. <FONT FACE="Courier New, monospace"><FONT SIZE=2>tLED.setCallback(
    2476. 

  2476. &amp;LEDOff);</FONT></FONT></P>
    2477. 

  2477. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>}</FONT></FONT></P>
    2478. 

  2478. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2479. 

  2479. </P>
    2480. 

  2480. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>void
    2481. 

  2481. LEDOff () {</FONT></FONT></P>
    2482. 

  2482. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2483. 

  2483. <FONT FACE="Courier New, monospace"><FONT SIZE=2>Serial.println(&quot;In
    2484. 

  2484. LEDOff&quot;);</FONT></FONT></P>
    2485. 

  2485. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2486. 

  2486. <FONT FACE="Courier New, monospace"><FONT SIZE=2>digitalWrite(LEDPIN,
    2487. 

  2487. LOW);</FONT></FONT></P>
    2488. 

  2488. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2489. 

  2489. <FONT FACE="Courier New, monospace"><FONT SIZE=2>tLED.setCallback(
    2490. 

  2490. &amp;LEDOn);</FONT></FONT></P>
    2491. 

  2491. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>}</FONT></FONT></P>
    2492. 

  2492. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2493. 

  2493. </P>
    2494. 

  2494. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>//
    2495. 

  2495. Note that LEDOff method serves as OnDisable method</FONT></FONT></P>
    2496. 

  2496. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>//
    2497. 

  2497. to make sure the LED is turned off when the tBlink</FONT></FONT></P>
    2498. 

  2498. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>//
    2499. 

  2499. task finishes (or disabled ahead of time)</FONT></FONT></P>
    2500. 

  2500. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2501. 

  2501. </P>
    2502. 

  2502. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>void
    2503. 

  2503. setup() {</FONT></FONT></P>
    2504. 

  2504. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2505. 

  2505. </P>
    2506. 

  2506. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2507. 

  2507. <FONT FACE="Courier New, monospace"><FONT SIZE=2>Serial.begin(115200);
    2508. 

  2508. </FONT></FONT>
    2509. 

  2509. </P>
    2510. 

  2510. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2511. 

  2511. <FONT FACE="Courier New, monospace"><FONT SIZE=2>pinMode(LEDPIN,
    2512. 

  2512. OUTPUT); </FONT></FONT>
    2513. 

  2513. </P>
    2514. 

  2514. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>}</FONT></FONT></P>
    2515. 

  2515. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2516. 

  2516. </P>
    2517. 

  2517. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>void
    2518. 

  2518. loop() {</FONT></FONT></P>
    2519. 

  2519. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2520. 

  2520. <FONT FACE="Courier New, monospace"><FONT SIZE=2>// put your main
    2521. 

  2521. code here, to run repeatedly:</FONT></FONT></P>
    2522. 

  2522. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2523. 

  2523. </P>
    2524. 

  2524. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2525. 

  2525. <FONT FACE="Courier New, monospace"><FONT SIZE=2>ts.execute();</FONT></FONT></P>
    2526. 

  2526. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>}</FONT></FONT></P>
    2527. 

  2527. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2528. 

  2528. </P>
    2529. 

  2529. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2530. 

  2530. </P>
    2531. 

  2531. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2532. 

  2532. </P>
    2533. 

  2533. <OL START=3>
    2534. 

  2534. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    2535. 

  2535. 	<FONT FACE="Times New Roman, serif"><B>USING STATUS REQUEST OBJECTS 
    2536. 

  2536. 	</B></FONT>
    2537. 

  2537. 	</P>
    2538. 

  2538. </OL>
    2539. 

  2539. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in; page-break-after: avoid">
    2540. 

  2540. <BR>
    2541. 

  2541. </P>
    2542. 

  2542. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Times New Roman, serif"><FONT SIZE=2 STYLE="font-size: 11pt">This
    2543. 

  2543. test emulates querying 3 sensors once every 10 seconds, each could
    2544. 

  2544. respond with a different delay (ultrasonic sensors for instance) and
    2545. 

  2545. printing a min value of the three when all three have reported their
    2546. 

  2546. values.</FONT></FONT></P>
    2547. 

  2547. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2548. 

  2548. </P>
    2549. 

  2549. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Times New Roman, serif"><FONT SIZE=2 STYLE="font-size: 11pt">The
    2550. 

  2550. overall timeout of 1 second is setup as well.</FONT></FONT></P>
    2551. 

  2551. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Times New Roman, serif"><FONT SIZE=2 STYLE="font-size: 11pt">An
    2552. 

  2552. error message needs to be printed if a timeout occurred instead of a
    2553. 

  2553. value.</FONT></FONT></P>
    2554. 

  2554. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2555. 

  2555. </P>
    2556. 

  2556. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2557. 

  2557. </P>
    2558. 

  2558. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>#define
    2559. 

  2559. _TASK_SLEEP_ON_IDLE_RUN</FONT></FONT></P>
    2560. 

  2560. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>#define
    2561. 

  2561. _TASK_STATUS_REQUEST</FONT></FONT></P>
    2562. 

  2562. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2563. 

  2563. </P>
    2564. 

  2564. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>#include
    2565. 

  2565. &lt;TaskScheduler.h&gt;</FONT></FONT></P>
    2566. 

  2566. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2567. 

  2567. </P>
    2568. 

  2568. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>StatusRequest
    2569. 

  2569. measure;</FONT></FONT></P>
    2570. 

  2570. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2571. 

  2571. </P>
    2572. 

  2572. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>Scheduler
    2573. 

  2573. ts; </FONT></FONT>
    2574. 

  2574. </P>
    2575. 

  2575. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2576. 

  2576. </P>
    2577. 

  2577. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>Task
    2578. 

  2578. tCycle(10000, TASK_FOREVER, &amp;CycleCallback, &amp;ts, true);</FONT></FONT></P>
    2579. 

  2579. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>Task
    2580. 

  2580. tMeasure(TASK_SECOND, TASK_ONCE, &amp;MeasureCallback, &amp;ts,
    2581. 

  2581. false, &amp;MeasureEnable, &amp;MeasureDisable);</FONT></FONT></P>
    2582. 

  2582. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>Task
    2583. 

  2583. tCalculate(&amp;CalcCallback, &amp;ts);</FONT></FONT></P>
    2584. 

  2584. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>Task
    2585. 

  2585. tSensor1(TASK_IMMEDIATE, TASK_ONCE, &amp;S1Callback, &amp;ts, false,
    2586. 

  2586. &amp;S1Enable);</FONT></FONT></P>
    2587. 

  2587. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>Task
    2588. 

  2588. tSensor2(TASK_IMMEDIATE, TASK_ONCE, &amp;S2Callback, &amp;ts, false,
    2589. 

  2589. &amp;S2Enable);</FONT></FONT></P>
    2590. 

  2590. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>Task
    2591. 

  2591. tSensor3(TASK_IMMEDIATE, TASK_ONCE, &amp;S3Callback, &amp;ts, false,
    2592. 

  2592. &amp;S3Enable);</FONT></FONT></P>
    2593. 

  2593. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2594. 

  2594. </P>
    2595. 

  2595. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2596. 

  2596. </P>
    2597. 

  2597. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>long
    2598. 

  2598. distance, d1, d2, d3;</FONT></FONT></P>
    2599. 

  2599. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2600. 

  2600. </P>
    2601. 

  2601. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>void
    2602. 

  2602. CycleCallback() {</FONT></FONT></P>
    2603. 

  2603. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2604. 

  2604. <FONT FACE="Courier New, monospace"><FONT SIZE=2>Serial.println(&quot;CycleCallback:
    2605. 

  2605. Initiating measurement cycle every 10 seconds&quot;);</FONT></FONT></P>
    2606. 

  2606. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2607. 

  2607. </P>
    2608. 

  2608. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2609. 

  2609. <FONT FACE="Courier New, monospace"><FONT SIZE=2>tMeasure.restartDelayed();</FONT></FONT></P>
    2610. 

  2610. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>}</FONT></FONT></P>
    2611. 

  2611. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2612. 

  2612. </P>
    2613. 

  2613. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2614. 

  2614. </P>
    2615. 

  2615. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2616. 

  2616. </P>
    2617. 

  2617. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>bool
    2618. 

  2618. MeasureEnable() {</FONT></FONT></P>
    2619. 

  2619. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2620. 

  2620. <FONT FACE="Courier New, monospace"><FONT SIZE=2>Serial.println(&quot;MeasureEnable:
    2621. 

  2621. Activating sensors&quot;);  </FONT></FONT>
    2622. 

  2622. </P>
    2623. 

  2623. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2624. 

  2624. </P>
    2625. 

  2625. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2626. 

  2626. <FONT FACE="Courier New, monospace"><FONT SIZE=2>distance = 0;</FONT></FONT></P>
    2627. 

  2627. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2628. 

  2628. <FONT FACE="Courier New, monospace"><FONT SIZE=2>measure.setWaiting(3);
    2629. 

  2629. // Set the StatusRequest to wait for 3 signals. </FONT></FONT>
    2630. 

  2630. </P>
    2631. 

  2631. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2632. 

  2632. <FONT FACE="Courier New, monospace"><FONT SIZE=2>tCalculate.waitFor(&amp;measure);</FONT></FONT></P>
    2633. 

  2633. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2634. 

  2634. </P>
    2635. 

  2635. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2636. 

  2636. <FONT FACE="Courier New, monospace"><FONT SIZE=2>tSensor1.restart();</FONT></FONT></P>
    2637. 

  2637. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2638. 

  2638. <FONT FACE="Courier New, monospace"><FONT SIZE=2>tSensor2.restart();</FONT></FONT></P>
    2639. 

  2639. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2640. 

  2640. <FONT FACE="Courier New, monospace"><FONT SIZE=2>tSensor3.restart();</FONT></FONT></P>
    2641. 

  2641. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2642. 

  2642. </P>
    2643. 

  2643. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2644. 

  2644. <FONT FACE="Courier New, monospace"><FONT SIZE=2>return true;</FONT></FONT></P>
    2645. 

  2645. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>}</FONT></FONT></P>
    2646. 

  2646. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2647. 

  2647. </P>
    2648. 

  2648. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>void
    2649. 

  2649. MeasureCallback() {</FONT></FONT></P>
    2650. 

  2650. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2651. 

  2651. <FONT FACE="Courier New, monospace"><FONT SIZE=2>Serial.println(&quot;MeasureCallback:
    2652. 

  2652. Invoked by calculate task or one second later&quot;);  </FONT></FONT>
    2653. 

  2653. </P>
    2654. 

  2654. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2655. 

  2655. </P>
    2656. 

  2656. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2657. 

  2657. <FONT FACE="Courier New, monospace"><FONT SIZE=2>if
    2658. 

  2658. (measure.pending()) {</FONT></FONT></P>
    2659. 

  2659. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    2660. 

  2660.  <FONT FACE="Courier New, monospace"><FONT SIZE=2>tCalculate.disable();</FONT></FONT></P>
    2661. 

  2661. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    2662. 

  2662.  <FONT FACE="Courier New, monospace"><FONT SIZE=2>measure.signalComplete(-1);
    2663. 

  2663.  // signal error</FONT></FONT></P>
    2664. 

  2664. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    2665. 

  2665.  <FONT FACE="Courier New, monospace"><FONT SIZE=2>Serial.println(&quot;MeasureCallback:
    2666. 

  2666. Timeout!&quot;);</FONT></FONT></P>
    2667. 

  2667. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2668. 

  2668. <FONT FACE="Courier New, monospace"><FONT SIZE=2>}</FONT></FONT></P>
    2669. 

  2669. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2670. 

  2670. <FONT FACE="Courier New, monospace"><FONT SIZE=2>else {</FONT></FONT></P>
    2671. 

  2671. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    2672. 

  2672.  <FONT FACE="Courier New, monospace"><FONT SIZE=2>Serial.print(&quot;MeasureCallback:
    2673. 

  2673. Min distance=&quot;);Serial.println(distance);</FONT></FONT></P>
    2674. 

  2674. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2675. 

  2675. <FONT FACE="Courier New, monospace"><FONT SIZE=2>}</FONT></FONT></P>
    2676. 

  2676. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>}</FONT></FONT></P>
    2677. 

  2677. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2678. 

  2678. </P>
    2679. 

  2679. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>void
    2680. 

  2680. MeasureDisable() {</FONT></FONT></P>
    2681. 

  2681. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2682. 

  2682. <FONT FACE="Courier New, monospace"><FONT SIZE=2>Serial.println(&quot;MeasureDisable:
    2683. 

  2683. Cleaning up&quot;);  </FONT></FONT>
    2684. 

  2684. </P>
    2685. 

  2685. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    2686. 

  2686. </P>
    2687. 

  2687. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2688. 

  2688. <FONT FACE="Courier New, monospace"><FONT SIZE=2>tSensor1.disable();</FONT></FONT></P>
    2689. 

  2689. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2690. 

  2690. <FONT FACE="Courier New, monospace"><FONT SIZE=2>tSensor2.disable();</FONT></FONT></P>
    2691. 

  2691. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2692. 

  2692. <FONT FACE="Courier New, monospace"><FONT SIZE=2>tSensor3.disable();</FONT></FONT></P>
    2693. 

  2693. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>}</FONT></FONT></P>
    2694. 

  2694. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2695. 

  2695. </P>
    2696. 

  2696. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2697. 

  2697. </P>
    2698. 

  2698. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>void
    2699. 

  2699. CalcCallback() {</FONT></FONT></P>
    2700. 

  2700. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2701. 

  2701. <FONT FACE="Courier New, monospace"><FONT SIZE=2>Serial.println(&quot;CalcCallback:
    2702. 

  2702. calculating&quot;);  </FONT></FONT>
    2703. 

  2703. </P>
    2704. 

  2704. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2705. 

  2705. <FONT FACE="Courier New, monospace"><FONT SIZE=2>distance = -1;</FONT></FONT></P>
    2706. 

  2706. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2707. 

  2707. <FONT FACE="Courier New, monospace"><FONT SIZE=2>if (
    2708. 

  2708. measure.getStatus() &gt;= 0) {  // only calculate if statusrequest
    2709. 

  2709. ended successfully</FONT></FONT></P>
    2710. 

  2710. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    2711. 

  2711.  <FONT FACE="Courier New, monospace"><FONT SIZE=2>distance = d1 &lt;
    2712. 

  2712. d2 ? d1 : d2;</FONT></FONT></P>
    2713. 

  2713. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    2714. 

  2714.  <FONT FACE="Courier New, monospace"><FONT SIZE=2>distance = d3 &lt;
    2715. 

  2715. distance ? d3 : distance;</FONT></FONT></P>
    2716. 

  2716. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    2717. 

  2717.  <FONT FACE="Courier New, monospace"><FONT SIZE=2>tMeasure.forceNextIteration();</FONT></FONT></P>
    2718. 

  2718. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2719. 

  2719. <FONT FACE="Courier New, monospace"><FONT SIZE=2>}</FONT></FONT></P>
    2720. 

  2720. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>}</FONT></FONT></P>
    2721. 

  2721. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2722. 

  2722. </P>
    2723. 

  2723. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2724. 

  2724. </P>
    2725. 

  2725. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>/**
    2726. 

  2726. Simulation code for sensor 1</FONT></FONT></P>
    2727. 

  2727. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> <FONT FACE="Courier New, monospace"><FONT SIZE=2>*
    2728. 

  2728.  ----------------------------</FONT></FONT></P>
    2729. 

  2729. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">
    2730. 

  2730. <FONT FACE="Courier New, monospace"><FONT SIZE=2>*/</FONT></FONT></P>
    2731. 

  2731. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>bool
    2732. 

  2732. S1Enable() {</FONT></FONT></P>
    2733. 

  2733. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2734. 

  2734. <FONT FACE="Courier New, monospace"><FONT SIZE=2>Serial.print(&quot;S1Enable:
    2735. 

  2735. Triggering sensor1. Delay=&quot;);  </FONT></FONT>
    2736. 

  2736. </P>
    2737. 

  2737. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2738. 

  2738. </P>
    2739. 

  2739. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2740. 

  2740. <FONT FACE="Courier New, monospace"><FONT SIZE=2>tSensor1.setInterval(
    2741. 

  2741. random(1200) );  // Simulating sensor delay, which could go over 1
    2742. 

  2742. second and cause timeout</FONT></FONT></P>
    2743. 

  2743. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2744. 

  2744. <FONT FACE="Courier New, monospace"><FONT SIZE=2>d1 = 0;</FONT></FONT></P>
    2745. 

  2745. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    2746. 

  2746. </P>
    2747. 

  2747. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2748. 

  2748. <FONT FACE="Courier New, monospace"><FONT SIZE=2>Serial.println(
    2749. 

  2749. tSensor1.getInterval() );</FONT></FONT></P>
    2750. 

  2750. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2751. 

  2751. <FONT FACE="Courier New, monospace"><FONT SIZE=2>return true;</FONT></FONT></P>
    2752. 

  2752. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>}</FONT></FONT></P>
    2753. 

  2753. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2754. 

  2754. </P>
    2755. 

  2755. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>void
    2756. 

  2756. S1Callback() {</FONT></FONT></P>
    2757. 

  2757. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2758. 

  2758. <FONT FACE="Courier New, monospace"><FONT SIZE=2>Serial.print(&quot;S1Callback:
    2759. 

  2759. Emulating measurement. d1=&quot;);  </FONT></FONT>
    2760. 

  2760. </P>
    2761. 

  2761. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2762. 

  2762. <FONT FACE="Courier New, monospace"><FONT SIZE=2>d1 = random(501); //
    2763. 

  2763. pick a value from 0 to 500 &quot;centimeters&quot; simulating a
    2764. 

  2764. measurement </FONT></FONT>
    2765. 

  2765. </P>
    2766. 

  2766. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2767. 

  2767. <FONT FACE="Courier New, monospace"><FONT SIZE=2>measure.signal();</FONT></FONT></P>
    2768. 

  2768. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    2769. 

  2769. </P>
    2770. 

  2770. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2771. 

  2771. <FONT FACE="Courier New, monospace"><FONT SIZE=2>Serial.println(d1); </FONT></FONT>
    2772. 

  2772. </P>
    2773. 

  2773. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>}</FONT></FONT></P>
    2774. 

  2774. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2775. 

  2775. </P>
    2776. 

  2776. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2777. 

  2777. </P>
    2778. 

  2778. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>/**
    2779. 

  2779. Simulation code for sensor 2</FONT></FONT></P>
    2780. 

  2780. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> <FONT FACE="Courier New, monospace"><FONT SIZE=2>*
    2781. 

  2781.  ----------------------------</FONT></FONT></P>
    2782. 

  2782. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">
    2783. 

  2783. <FONT FACE="Courier New, monospace"><FONT SIZE=2>*/</FONT></FONT></P>
    2784. 

  2784. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>bool
    2785. 

  2785. S2Enable() {</FONT></FONT></P>
    2786. 

  2786. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2787. 

  2787. <FONT FACE="Courier New, monospace"><FONT SIZE=2>Serial.print(&quot;S2Enable:
    2788. 

  2788. Triggering sensor2. Delay=&quot;);  </FONT></FONT>
    2789. 

  2789. </P>
    2790. 

  2790. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2791. 

  2791. </P>
    2792. 

  2792. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2793. 

  2793. <FONT FACE="Courier New, monospace"><FONT SIZE=2>tSensor2.setInterval(
    2794. 

  2794. random(1200) );  // Simulating sensor delay, which could go over 1
    2795. 

  2795. second and cause timeout</FONT></FONT></P>
    2796. 

  2796. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2797. 

  2797. <FONT FACE="Courier New, monospace"><FONT SIZE=2>d2 = 0;</FONT></FONT></P>
    2798. 

  2798. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2799. 

  2799. </P>
    2800. 

  2800. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2801. 

  2801. <FONT FACE="Courier New, monospace"><FONT SIZE=2>Serial.println(
    2802. 

  2802. tSensor2.getInterval() );</FONT></FONT></P>
    2803. 

  2803. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2804. 

  2804. <FONT FACE="Courier New, monospace"><FONT SIZE=2>return true;</FONT></FONT></P>
    2805. 

  2805. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>}</FONT></FONT></P>
    2806. 

  2806. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2807. 

  2807. </P>
    2808. 

  2808. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>void
    2809. 

  2809. S2Callback() {</FONT></FONT></P>
    2810. 

  2810. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2811. 

  2811. <FONT FACE="Courier New, monospace"><FONT SIZE=2>Serial.print(&quot;S2Callback:
    2812. 

  2812. Emulating measurement. d2=&quot;);  </FONT></FONT>
    2813. 

  2813. </P>
    2814. 

  2814. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2815. 

  2815. <FONT FACE="Courier New, monospace"><FONT SIZE=2>d2 = random(501); //
    2816. 

  2816. pick a value from 0 to 500 &quot;centimeters&quot; simulating a
    2817. 

  2817. measurement</FONT></FONT></P>
    2818. 

  2818. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2819. 

  2819. <FONT FACE="Courier New, monospace"><FONT SIZE=2>measure.signal();</FONT></FONT></P>
    2820. 

  2820. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2821. 

  2821. </P>
    2822. 

  2822. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2823. 

  2823. <FONT FACE="Courier New, monospace"><FONT SIZE=2>Serial.println(d2); 
    2824. 

  2824. </FONT></FONT>
    2825. 

  2825. </P>
    2826. 

  2826. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>}</FONT></FONT></P>
    2827. 

  2827. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2828. 

  2828. </P>
    2829. 

  2829. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2830. 

  2830. </P>
    2831. 

  2831. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>/**
    2832. 

  2832. Simulation code for sensor 3</FONT></FONT></P>
    2833. 

  2833. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> <FONT FACE="Courier New, monospace"><FONT SIZE=2>*
    2834. 

  2834.  ----------------------------</FONT></FONT></P>
    2835. 

  2835. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">
    2836. 

  2836. <FONT FACE="Courier New, monospace"><FONT SIZE=2>*/</FONT></FONT></P>
    2837. 

  2837. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>bool
    2838. 

  2838. S3Enable() {</FONT></FONT></P>
    2839. 

  2839. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2840. 

  2840. <FONT FACE="Courier New, monospace"><FONT SIZE=2>Serial.print(&quot;S3Enable:
    2841. 

  2841. Triggering sensor3. Delay=&quot;);  </FONT></FONT>
    2842. 

  2842. </P>
    2843. 

  2843. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2844. 

  2844. </P>
    2845. 

  2845. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2846. 

  2846. <FONT FACE="Courier New, monospace"><FONT SIZE=2>tSensor3.setInterval(
    2847. 

  2847. random(1200) );  // Simulating sensor delay, which could go over 1
    2848. 

  2848. second and cause timeout</FONT></FONT></P>
    2849. 

  2849. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2850. 

  2850. <FONT FACE="Courier New, monospace"><FONT SIZE=2>d3 = 0;</FONT></FONT></P>
    2851. 

  2851. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2852. 

  2852. </P>
    2853. 

  2853. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2854. 

  2854. <FONT FACE="Courier New, monospace"><FONT SIZE=2>Serial.println(
    2855. 

  2855. tSensor3.getInterval() );</FONT></FONT></P>
    2856. 

  2856. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2857. 

  2857. <FONT FACE="Courier New, monospace"><FONT SIZE=2>return true;</FONT></FONT></P>
    2858. 

  2858. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>}</FONT></FONT></P>
    2859. 

  2859. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2860. 

  2860. </P>
    2861. 

  2861. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>void
    2862. 

  2862. S3Callback() {</FONT></FONT></P>
    2863. 

  2863. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2864. 

  2864. <FONT FACE="Courier New, monospace"><FONT SIZE=2>Serial.print(&quot;S3Callback:
    2865. 

  2865. Emulating measurement. d3=&quot;);  </FONT></FONT>
    2866. 

  2866. </P>
    2867. 

  2867. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2868. 

  2868. <FONT FACE="Courier New, monospace"><FONT SIZE=2>d3 = random(501); //
    2869. 

  2869. pick a value from 0 to 500 &quot;centimeters&quot; simulating a
    2870. 

  2870. measurement</FONT></FONT></P>
    2871. 

  2871. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2872. 

  2872. <FONT FACE="Courier New, monospace"><FONT SIZE=2>measure.signal();</FONT></FONT></P>
    2873. 

  2873. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">  
    2874. 

  2874. </P>
    2875. 

  2875. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2876. 

  2876. <FONT FACE="Courier New, monospace"><FONT SIZE=2>Serial.println(d3); </FONT></FONT>
    2877. 

  2877. </P>
    2878. 

  2878. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>}</FONT></FONT></P>
    2879. 

  2879. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2880. 

  2880. </P>
    2881. 

  2881. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2882. 

  2882. </P>
    2883. 

  2883. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>/**
    2884. 

  2884. Main Arduino code</FONT></FONT></P>
    2885. 

  2885. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> <FONT FACE="Courier New, monospace"><FONT SIZE=2>*
    2886. 

  2886.  Not much is left here - everything is taken care of by the framework</FONT></FONT></P>
    2887. 

  2887. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in">
    2888. 

  2888. <FONT FACE="Courier New, monospace"><FONT SIZE=2>*/</FONT></FONT></P>
    2889. 

  2889. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>void
    2890. 

  2890. setup() {</FONT></FONT></P>
    2891. 

  2891. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2892. 

  2892. </P>
    2893. 

  2893. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2894. 

  2894. <FONT FACE="Courier New, monospace"><FONT SIZE=2>Serial.begin(115200);</FONT></FONT></P>
    2895. 

  2895. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2896. 

  2896. <FONT FACE="Courier New, monospace"><FONT SIZE=2>Serial.println(&quot;TaskScheduler
    2897. 

  2897. StatusRequest Sensor Emulation Test. Complex Test.&quot;);  </FONT></FONT>
    2898. 

  2898. </P>
    2899. 

  2899. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2900. 

  2900. <FONT FACE="Courier New, monospace"><FONT SIZE=2>randomSeed(analogRead(A1)+millis());</FONT></FONT></P>
    2901. 

  2901. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>}</FONT></FONT></P>
    2902. 

  2902. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2903. 

  2903. </P>
    2904. 

  2904. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>void
    2905. 

  2905. loop() {</FONT></FONT></P>
    2906. 

  2906. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"> 
    2907. 

  2907. <FONT FACE="Courier New, monospace"><FONT SIZE=2>ts.execute();</FONT></FONT></P>
    2908. 

  2908. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>}</FONT></FONT></P>
    2909. 

  2909. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2910. 

  2910. </P>
    2911. 

  2911. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2912. 

  2912. </P>
    2913. 

  2913. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2914. 

  2914. </P>
    2915. 

  2915. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2916. 

  2916. </P>
    2917. 

  2917. <OL START=3>
    2918. 

  2918. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    2919. 

  2919. 	<FONT FACE="Times New Roman, serif"><B>USING LOCAL TASK STORAGE
    2920. 

  2920. 	POINTER  </B></FONT>
    2921. 

  2921. 	</P>
    2922. 

  2922. </OL>
    2923. 

  2923. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in; page-break-after: avoid">
    2924. 

  2924. <BR>
    2925. 

  2925. </P>
    2926. 

  2926. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Times New Roman, serif"><FONT SIZE=2 STYLE="font-size: 11pt">Tasks
    2927. 

  2927. can store a pointer to specific variable, structure or array, which
    2928. 

  2928. represents variables specific for a particular task. This may be
    2929. 

  2929. needed if you plan to use same callback method for multiple tasks.</FONT></FONT></P>
    2930. 

  2930. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Times New Roman, serif"><FONT SIZE=2 STYLE="font-size: 11pt">Consider
    2931. 

  2931. a scenario where you have several sensors of the same type. The
    2932. 

  2932. actual process of triggering measurement and collecting information
    2933. 

  2933. is identical. The only difference is the sensor address and a
    2934. 

  2934. variable for storing the results.  </FONT></FONT>
    2935. 

  2935. </P>
    2936. 

  2936. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Times New Roman, serif"><FONT SIZE=2 STYLE="font-size: 11pt">In
    2937. 

  2937. this case each of the tasks, which performs measurement will utilize
    2938. 

  2938. the same callback methods. The only difference will be the variables
    2939. 

  2939. (specific for each of the sensor). </FONT></FONT>
    2940. 

  2940. </P>
    2941. 

  2941. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2942. 

  2942. </P>
    2943. 

  2943. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Times New Roman, serif"><FONT SIZE=2 STYLE="font-size: 11pt">Let's
    2944. 

  2944. define a sensor data structure and declare a couple of variables (for
    2945. 

  2945. 2 sensors for instance)</FONT></FONT></P>
    2946. 

  2946. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2947. 

  2947. </P>
    2948. 

  2948. <P LANG="" CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in">
    2949. 

  2949. <FONT FACE="Courier New, monospace"><FONT SIZE=2>typedef struct {</FONT></FONT></P>
    2950. 

  2950. <P LANG="" CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in">
    2951. 

  2951. <FONT FACE="Courier New, monospace"><FONT SIZE=2>	unsigned int
    2952. 

  2952. 	address;</FONT></FONT></P>
    2953. 

  2953. <P LANG="" CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in">
    2954. 

  2954. <FONT FACE="Courier New, monospace"><FONT SIZE=2>	unsigned
    2955. 

  2955. long	distance;</FONT></FONT></P>
    2956. 

  2956. <P LANG="" CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in">
    2957. 

  2957. <FONT FACE="Courier New, monospace"><FONT SIZE=2>} sensor_data;</FONT></FONT></P>
    2958. 

  2958. <P LANG="" CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in">
    2959. 

  2959. <BR>
    2960. 

  2960. </P>
    2961. 

  2961. <P LANG="" CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in">
    2962. 

  2962. <FONT FACE="Courier New, monospace"><FONT SIZE=2>sensor_data s1, s2; </FONT></FONT>
    2963. 

  2963. </P>
    2964. 

  2964. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2965. 

  2965. </P>
    2966. 

  2966. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Times New Roman, serif"><FONT SIZE=2 STYLE="font-size: 11pt">Two
    2967. 

  2967. separate tasks are running to collect sensor data.</FONT></FONT></P>
    2968. 

  2968. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Times New Roman, serif"><FONT SIZE=2 STYLE="font-size: 11pt">(Note
    2969. 

  2969. that both tasks refer to the same callback methods)</FONT></FONT></P>
    2970. 

  2970. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2971. 

  2971. </P>
    2972. 

  2972. <P LANG="" CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in">
    2973. 

  2973. <FONT FACE="Courier New, monospace"><FONT SIZE=2>Scheduler ts;</FONT></FONT></P>
    2974. 

  2974. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2><SPAN LANG="">Task
    2975. 

  2975. t1(100, </SPAN>TASK_FOREVER<SPAN LANG="">, &amp;Measure, &amp;ts,
    2976. 

  2976. false, &amp;MeasureOn); </SPAN></FONT></FONT>
    2977. 

  2977. </P>
    2978. 

  2978. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2><SPAN LANG="">Task
    2979. 

  2979. t2(100, </SPAN>TASK_FOREVER<SPAN LANG="">, &amp;Measure, &amp;ts,
    2980. 

  2980. false, &amp;MeasureOn); </SPAN></FONT></FONT>
    2981. 

  2981. </P>
    2982. 

  2982. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><BR>
    2983. 

  2983. </P>
    2984. 

  2984. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Times New Roman, serif"><FONT SIZE=2 STYLE="font-size: 11pt">Assign
    2985. 

  2985. pointers to the respective variables in the <B>setup</B>() method:</FONT></FONT></P>
    2986. 

  2986. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    2987. 

  2987. </P>
    2988. 

  2988. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>void
    2989. 

  2989. setup() {</FONT></FONT></P>
    2990. 

  2990. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><BR>
    2991. 

  2991. </P>
    2992. 

  2992. <P CLASS="western" STYLE="margin-left: 1.48in; margin-bottom: 0in">…</P>
    2993. 

  2993. <P CLASS="western" STYLE="margin-left: 1.48in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>t1.setLtsPointer(&amp;s1);</FONT></FONT></P>
    2994. 

  2994. <P CLASS="western" STYLE="margin-left: 1.48in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>t2.setLtsPointer(&amp;s2);</FONT></FONT></P>
    2995. 

  2995. <P CLASS="western" STYLE="margin-left: 1.48in; margin-bottom: 0in">…</P>
    2996. 

  2996. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><BR>
    2997. 

  2997. </P>
    2998. 

  2998. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>}</FONT></FONT></P>
    2999. 

  2999. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><BR>
    3000. 

  3000. </P>
    3001. 

  3001. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Times New Roman, serif"><FONT SIZE=2 STYLE="font-size: 11pt">Obtain
    3002. 

  3002. reference to specific <B>sensor_data</B> structure inside the common
    3003. 

  3003. callback method:</FONT></FONT></P>
    3004. 

  3004. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    3005. 

  3005. </P>
    3006. 

  3006. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>void
    3007. 

  3007. Measure() {</FONT></FONT></P>
    3008. 

  3008. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>	Task&amp;
    3009. 

  3009. T = ts.currentTask(); </FONT></FONT>
    3010. 

  3010. </P>
    3011. 

  3011. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>	Sensor_data&amp;
    3012. 

  3012. V = *((sensor_data*) T.getLtsPointer());</FONT></FONT></P>
    3013. 

  3013. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>//
    3014. 

  3014. For t1, V will be pointing at s1</FONT></FONT></P>
    3015. 

  3015. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>//
    3016. 

  3016. For t2, V will be pointing at s2</FONT></FONT></P>
    3017. 

  3017. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><BR>
    3018. 

  3018. </P>
    3019. 

  3019. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>//
    3020. 

  3020. Alternatively use the Scheduler method:</FONT></FONT></P>
    3021. 

  3021. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>	Sensor_data&amp;
    3022. 

  3022. V1 = *((sensor_data*) ts.currentLts());</FONT></FONT></P>
    3023. 

  3023. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><BR>
    3024. 

  3024. </P>
    3025. 

  3025. <P CLASS="western" STYLE="margin-left: 0.98in; text-indent: 0.49in; margin-bottom: 0in">
    3026. 

  3026. …</P>
    3027. 

  3027. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>	V.distance
    3028. 

  3028. = &lt;calculate your values here&gt;;</FONT></FONT></P>
    3029. 

  3029. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>}</FONT></FONT></P>
    3030. 

  3030. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><BR>
    3031. 

  3031. </P>
    3032. 

  3032. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    3033. 

  3033. </P>
    3034. 

  3034. <OL START=3>
    3035. 

  3035. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in; page-break-after: avoid">
    3036. 

  3036. 	<FONT FACE="Times New Roman, serif"><B>ENABLING TASK PRIORITIZATION 
    3037. 

  3037. 	</B></FONT>
    3038. 

  3038. 	</P>
    3039. 

  3039. </OL>
    3040. 

  3040. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in; page-break-after: avoid">
    3041. 

  3041. <BR>
    3042. 

  3042. </P>
    3043. 

  3043. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Times New Roman, serif"><FONT SIZE=2 STYLE="font-size: 11pt">In
    3044. 

  3044. certain cases you want a task to be invoked before others in case of
    3045. 

  3045. scheduling collision (tasks ready to be invoked at the same time). In
    3046. 

  3046. a flat execution chain scenario tasks are evaluated for execution in
    3047. 

  3047. the order they were added to the chain. Therefore a single task has
    3048. 

  3048. to wait for the rest of the chain to be evaluated to get a chance
    3049. 

  3049. again. </FONT></FONT>
    3050. 

  3050. </P>
    3051. 

  3051. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Times New Roman, serif"><FONT SIZE=2 STYLE="font-size: 11pt">Consider
    3052. 

  3052. a scenario where a task taking gyroscope measurements has to be
    3053. 

  3053. invoked as close to the actual scheduling time as possible. That is
    3054. 

  3054. when task prioritization comes to help.  </FONT></FONT>
    3055. 

  3055. </P>
    3056. 

  3056. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Times New Roman, serif"><FONT SIZE=2 STYLE="font-size: 11pt">Let’s
    3057. 

  3057. say tasks t4 and t5 are taking measurements from gyroscope and
    3058. 

  3058. accelerometer, and tasks t1, t2 and t3 are doing something less
    3059. 

  3059. important.</FONT></FONT></P>
    3060. 

  3060. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Times New Roman, serif"><FONT SIZE=2 STYLE="font-size: 11pt">This
    3061. 

  3061. is how such setup is coded:</FONT></FONT></P>
    3062. 

  3062. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    3063. 

  3063. </P>
    3064. 

  3064. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>#define
    3065. 

  3065. _TASK_PRIORITY</FONT></FONT></P>
    3066. 

  3066. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>#include
    3067. 

  3067. &lt;TaskScheduler.h&gt;</FONT></FONT></P>
    3068. 

  3068. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><BR>
    3069. 

  3069. </P>
    3070. 

  3070. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>Scheduler
    3071. 

  3071. r, hpr;</FONT></FONT></P>
    3072. 

  3072. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><BR>
    3073. 

  3073. </P>
    3074. 

  3074. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>//
    3075. 

  3075. Tasks</FONT></FONT></P>
    3076. 

  3076. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>Task
    3077. 

  3077. t1(1000, TASK_FOREVER, &amp;tCallback, &amp;r);  //base priority</FONT></FONT></P>
    3078. 

  3078. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>Task
    3079. 

  3079. t2(2000, TASK_FOREVER, &amp;tCallback, &amp;r);</FONT></FONT></P>
    3080. 

  3080. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>Task
    3081. 

  3081. t3(3000, TASK_FOREVER, &amp;tCallback, &amp;r);</FONT></FONT></P>
    3082. 

  3082. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><BR>
    3083. 

  3083. </P>
    3084. 

  3084. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>Task
    3085. 

  3085. t4(10, TASK_FOREVER, &amp;tCallback, &amp;hpr);  // higher priority</FONT></FONT></P>
    3086. 

  3086. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>Task
    3087. 

  3087. t5(100, TASK_FOREVER, &amp;tCallback, &amp;hpr);  //higher priority</FONT></FONT></P>
    3088. 

  3088. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><BR>
    3089. 

  3089. </P>
    3090. 

  3090. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in">…</P>
    3091. 

  3091. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><BR>
    3092. 

  3092. </P>
    3093. 

  3093. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>void
    3094. 

  3094. setup () {</FONT></FONT></P>
    3095. 

  3095. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in">  
    3096. 

  3096. </P>
    3097. 

  3097. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"> 
    3098. 

  3098. …</P>
    3099. 

  3099. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><BR>
    3100. 

  3100. </P>
    3101. 

  3101. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"> 
    3102. 

  3102. <FONT FACE="Courier New, monospace"><FONT SIZE=2>r.setHighPriorityScheduler(&amp;hpr);
    3103. 

  3103. </FONT></FONT>
    3104. 

  3104. </P>
    3105. 

  3105. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"> 
    3106. 

  3106. <FONT FACE="Courier New, monospace"><FONT SIZE=2>r.enableAll(true);
    3107. 

  3107. // this will recursively enable the higher priority tasks as well</FONT></FONT></P>
    3108. 

  3108. <P CLASS="western" STYLE="margin-left: 0.98in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>}</FONT></FONT></P>
    3109. 

  3109. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    3110. 

  3110. </P>
    3111. 

  3111. <OL START=3>
    3112. 

  3112. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in"><FONT FACE="Times New Roman, serif"><B>FUTHER
    3113. 

  3113. 	INFROMATION</B></FONT></P>
    3114. 

  3114. </OL>
    3115. 

  3115. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    3116. 

  3116. </P>
    3117. 

  3117. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>Please
    3118. 

  3118. refer to examples, provided with TaskScheduler package for further
    3119. 

  3119. information and implementation options.</FONT></FONT></P>
    3120. 

  3120. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><BR>
    3121. 

  3121. </P>
    3122. 

  3122. <P CLASS="western" STYLE="margin-left: 0.49in; margin-bottom: 0in"><FONT FACE="Courier New, monospace"><FONT SIZE=2>Real
    3123. 

  3123. time examples of TaskScheduler are available here:</FONT></FONT></P>
    3124. 

  3124. <OL>
    3125. 

  3125. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in"><FONT COLOR="#0000ff"><U><A HREF="http://www.instructables.com/id/APIS-Automated-Plant-Irrigation-System/"><FONT FACE="Courier New, monospace">http://www.instructables.com/id/APIS-Automated-Plant-Irrigation-System/</FONT></A></U></FONT></P>
    3126. 

  3126. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in"><FONT COLOR="#0000ff"><U><A HREF="http://www.instructables.com/id/Wave-your-hand-to-control-OWI-Robotic-Arm-no-strin/"><FONT FACE="Courier New, monospace">http://www.instructables.com/id/Wave-your-hand-to-control-OWI-Robotic-Arm-no-strin/</FONT></A></U></FONT></P>
    3127. 

  3127. 	<LI><P CLASS="western" STYLE="margin-bottom: 0in"><FONT COLOR="#0000ff"><U><A HREF="http://www.instructables.com/id/Arduino-Nano-based-Hexbug-Scarab-Robotic-Spider"><FONT FACE="Courier New, monospace">http://www.instructables.com/id/Arduino-Nano-based-Hexbug-Scarab-Robotic-Spider</FONT></A></U></FONT></P>
    3128. 

  3128. </OL>
    3129. 

  3129. <P CLASS="western" STYLE="margin-bottom: 0in"><BR>
    3130. 

  3130. </P>
    3131. 

  3131. <DIV TYPE=FOOTER>
    3132. 

  3132. 	<P STYLE="margin-top: 0.35in; margin-bottom: 0in">	<SDFIELD TYPE=PAGE SUBTYPE=RANDOM FORMAT=ARABIC>33</SDFIELD></P>
    3133. 

  3133. </DIV>
    3134. 

  3134. </BODY>
    3135. 

  3135. </HTML>
    3136.