Merge pull request #372 from hathach/add-rtt

Add rtt as logger option

.github/ISSUE_TEMPLATE/bug_report.md

@@ -7,17 +7,20 @@ assignees: ''
 
 ---
 
-**Set up (mandatory):**
-Provide details of your setup help us to reproduce the issue as quick as possible  
+**Set up**
+[Mandatory] Provide details of your setup help us to reproduce the issue as quick as possible  
  - **PC OS**   : Ubuntu 18.04 / Windows 10/ macOS 10.15 
  - **Board**   : Feather nRF52840 Express
  - **Firmware**: examples/device/cdc_msc
 
-**Bug Description**
-Describe what the bug is.
+**Describe the bug**
+A clear and concise description of what the bug is.
 
-**Reproduce**
+**To reproduce**
 Steps to reproduce the behavior:
 1. Go to '...'
 2. Click on '....'
 3. See error
+
+**Log & screenshots**
+If applicable, add screenshots and TinyUSB's log to help explain your problem. To enable logging, add `LOG=2` to your make command if building with stock examples or set `CFG_TUSB_DEBUG=2` in your tusb_config.h. More information can be found at [example's readme](/examples/readme.md)

.github/ISSUE_TEMPLATE/feature_request.md

@@ -7,5 +7,8 @@ assignees: ''
 
 ---
 
-**Feature Description**
-Describe your feature
+**Is your feature request related to a problem? Please describe.**
+A clear and concise description of what the problem is. Ex. I'm always frustrated when [...]
+
+**Describe the solution you'd like**
+A clear and concise description of what you want to happen.

.github/ISSUE_TEMPLATE/question.md

@@ -7,4 +7,4 @@ assignees: ''
 
 ---
 
-**Question Description**
+**Describe what the question is**

README.md

@@ -73,10 +73,6 @@ TinyUSB is completely thread-safe by pushing all ISR events into a central queue
 - **FreeRTOS**
 - **Mynewt** Due to the newt package build system, Mynewt examples are better to be on its [own repo](https://github.com/hathach/mynewt-tinyusb-example) 
 
-## Compiler & IDE
-
-The stack is developed with GCC compiler and should be compilable with others. The `examples` folder provides Makefile and Segger Embedded Studio build support. [Here are example build instructions](examples/readme.md).
-
 ## Getting Started
 
 [Here are the details for getting started](docs/getting_started.md) with the stack.

docs/getting_started.md

@@ -4,8 +4,6 @@
 
 ```
 git clone git@github.com:hathach/tinyusb.git tinyusb
-cd tinyusb
-git submodule update --init
 ```
 
 *examples* is the folder where all the application & project files are located. There are demos for both device and hosts. For each, there are different projects for each of supported RTOS. Click to have more information on how to [build](../examples/readme.md) and run [device](../examples/device/readme.md) demos.

examples/make.mk

@@ -75,7 +75,17 @@ else
 	CFLAGS += -Os
 endif
 
-# TUSB Logging option
+# Log level is mapped to TUSB DEBUG option
 ifneq ($(LOG),)
   CFLAGS += -DCFG_TUSB_DEBUG=$(LOG)
 endif
+
+# Logger: default is UART, can be set to RTT
+ifeq ($(LOGGER),rtt)
+	RTT_SRC = lib/SEGGER_RTT
+	
+	CFLAGS += -DLOGGER_RTT
+  INC   += $(TOP)/$(RTT_SRC)/RTT
+  SRC_C += $(RTT_SRC)/RTT/SEGGER_RTT_printf.c
+  SRC_C += $(RTT_SRC)/RTT/SEGGER_RTT.c
+endif

examples/readme.md

@@ -32,12 +32,38 @@ Then compile with `make BOARD=[your_board] all`, for example
 $ make BOARD=feather_nrf52840_express all
 ```
 
+### Debug Log
+
+### Log Level
+
+Should you have an issue running example and/or submitting an bug report. You could enable TinyUSB built-in debug logging with optional `LOG=`. LOG=1 will only print out error message, LOG=2 print more information with on-going events. LOG=3 or higher is not used yet. 
+
+```
+$ make LOG=2 BOARD=feather_nrf52840_express all
+```
+
+### Logger
+
+By default log message is printed via on-board UART which is slow and take lots of CPU time comparing to USB speed. If your board support on-board/external JLink debugger, it would be more efficient to use it with [RTT protocol](https://www.segger.com/products/debug-probes/j-link/technology/about-real-time-transfer/) for logging. To do that add option `LOGGER=rtt` to build command e.g
+
+```
+$ make LOG=2 LOGGER=rtt BOARD=feather_nrf52840_express all
+```
+
+The log can be retrieved by JLink RTT Viewer/Client/Logger software which is bundled with their JLink driver.
+
 ## Flash
 
-`flash` target will use the on-board debugger (jlink/cmsisdap/stlink/dfu) to flash the binary. We should install those debugger/programmer software in advance. Furthermore, since external jlink can be used with most of the board, there is also `flash-jlink` target for your convenience.
+`flash` target will use the default on-board debugger (jlink/cmsisdap/stlink/dfu) to flash the binary, please install those support software in advance. Some board use bootloader/DFU via serial which is required to pass to make command
 
 ```
 $ make BOARD=feather_nrf52840_express flash
+$ make SERIAL=/dev/ttyACM0 BOARD=feather_nrf52840_express flash
+```
+
+Since jlink can be used with most of the boards, there is also `flash-jlink` target for your convenience.
+
+```
 $ make BOARD=feather_nrf52840_express flash-jlink
 ```
 
@@ -46,4 +72,3 @@ Some board use uf2 bootloader for drag & drop in to mass storage device, uf2 can
 ```
 $ make BOARD=feather_nrf52840_express all uf2
 ```
-

hw/bsp/board.c

@@ -32,25 +32,31 @@
   #define sys_write   _write
   #define sys_read    _read
 #endif
+
 //--------------------------------------------------------------------+
-// MACRO TYPEDEF CONSTANT ENUM DECLARATION
+// newlib read()/write() retarget
 //--------------------------------------------------------------------+
 
-//#if CFG_PRINTF_TARGET == PRINTF_TARGET_UART
-//  #define retarget_getchar    board_uart_getchar
-//  #define retarget_putchar    board_uart_putchar
-//#elif CFG_PRINTF_TARGET == PRINTF_TARGET_SWO
-//  volatile int32_t ITM_RxBuffer;  // keil variable to read from SWO
-//	#define retarget_getchar    ITM_ReceiveChar
-//	#define retarget_putchar    ITM_SendChar
-//#else
-//	#error Target is not implemented yet
-//#endif
+#ifdef LOGGER_RTT
 
-//------------- IMPLEMENTATION -------------//
+#include "SEGGER_RTT.h"
 
-// newlib read()/write() retarget
+TU_ATTR_USED int sys_write (int fhdl, const void *buf, size_t count)
+{
+  (void) fhdl;
+  SEGGER_RTT_Write(0, (char*) buf, (int) count);
+  return count;
+}
+
+TU_ATTR_USED int sys_read (int fhdl, char *buf, size_t count)
+{
+  (void) fhdl;
+  return SEGGER_RTT_Read(0, buf, count);
+}
 
+#else
+
+// Default logger is on-board UART
 TU_ATTR_USED int sys_write (int fhdl, const void *buf, size_t count)
 {
   (void) fhdl;
@@ -62,3 +68,5 @@ TU_ATTR_USED int sys_read (int fhdl, char *buf, size_t count)
   (void) fhdl;
   return board_uart_read((uint8_t*) buf, count);
 }
+
+#endif

lib/SEGGER_RTT/License.txt

@@ -0,0 +1,34 @@
+Important - Read carefully:
+
+SEGGER RTT - Real Time Transfer for embedded targets
+
+All rights reserved.
+
+SEGGER strongly recommends to not make any changes
+to or modify the source code of this software in order to stay
+compatible with the RTT protocol and J-Link.
+
+Redistribution and use in source and binary forms, with or
+without modification, are permitted provided that the following
+condition is met:
+
+o Redistributions of source code must retain the above copyright
+  notice, this condition and the following disclaimer.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
+CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
+INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL SEGGER Microcontroller BE LIABLE FOR
+ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
+USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
+DAMAGE.
+
+
+(c) 2014 - 2016  SEGGER Microcontroller GmbH
+www.segger.com

lib/SEGGER_RTT/README.txt

@@ -0,0 +1,20 @@
+README.txt for the SEGGER RTT Implementation Pack.
+
+Included files:
+===============
+Root Directory
+  - Examples
+    - Main_RTT_InputEchoApp.c    - Sample application which echoes input on Channel 0.
+    - Main_RTT_MenuApp.c         - Sample application to demonstrate RTT bi-directional functionality.
+    - Main_RTT_PrintfTest.c      - Sample application to test RTT small printf implementation.
+    - Main_RTT_SpeedTestApp.c    - Sample application for measuring RTT performance. embOS needed.
+  - RTT
+    - SEGGER_RTT.c                - The RTT implementation.
+    - SEGGER_RTT.h                - Header for RTT implementation.
+    - SEGGER_RTT_Conf.h           - Pre-processor configuration for the RTT implementation.
+    - SEGGER_RTT_Printf.c         - Simple implementation of printf to write formatted strings via RTT.
+  - Syscalls
+    - RTT_Syscalls_GCC.c          - Low-level syscalls to retarget printf() to RTT with GCC / Newlib.
+    - RTT_Syscalls_IAR.c          - Low-level syscalls to retarget printf() to RTT with IAR compiler.
+    - RTT_Syscalls_KEIL.c         - Low-level syscalls to retarget printf() to RTT with KEIL/uVision compiler.
+    - RTT_Syscalls_SES.c          - Low-level syscalls to retarget printf() to RTT with SEGGER Embedded Studio.

lib/segger_rtt/SEGGER_RTT.c → lib/SEGGER_RTT/RTT/SEGGER_RTT.c

@@ -3,32 +3,34 @@
 *                        The Embedded Experts                        *
 **********************************************************************
 *                                                                    *
-*            (c) 2014 - 2018 SEGGER Microcontroller GmbH             *
+*            (c) 1995 - 2019 SEGGER Microcontroller GmbH             *
 *                                                                    *
-*           www.segger.com     Support: support@segger.com           *
+*       www.segger.com     Support: support@segger.com               *
+*                                                                    *
+**********************************************************************
+*                                                                    *
+*       SEGGER RTT * Real Time Transfer for embedded targets         *
 *                                                                    *
 **********************************************************************
 *                                                                    *
 * All rights reserved.                                               *
 *                                                                    *
+* SEGGER strongly recommends to not make any changes                 *
+* to or modify the source code of this software in order to stay     *
+* compatible with the RTT protocol and J-Link.                       *
+*                                                                    *
 * Redistribution and use in source and binary forms, with or         *
 * without modification, are permitted provided that the following    *
-* conditions are met:                                                *
-*                                                                    *
-* - Redistributions of source code must retain the above copyright   *
-*   notice, this list of conditions and the following disclaimer.    *
+* condition is met:                                                  *
 *                                                                    *
-* - Neither the name of SEGGER Microcontroller GmbH                  *
-*   nor the names of its contributors may be used to endorse or      *
-*   promote products derived from this software without specific     *
-*   prior written permission.                                        *
+* o Redistributions of source code must retain the above copyright   *
+*   notice, this condition and the following disclaimer.             *
 *                                                                    *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND             *
 * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,        *
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF           *
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE           *
-* DISCLAIMED.                                                        *
-* IN NO EVENT SHALL SEGGER Microcontroller GmbH BE LIABLE FOR        *
+* DISCLAIMED. IN NO EVENT SHALL SEGGER Microcontroller BE LIABLE FOR *
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR           *
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT  *
 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;    *
@@ -44,7 +46,7 @@ File    : SEGGER_RTT.c
 Purpose : Implementation of SEGGER real-time transfer (RTT) which
           allows real-time communication on targets which support
           debugger memory accesses while the CPU is running.
-Revision: $Rev: 12804 $
+Revision: $Rev: 17697 $
 
 Additional information:
           Type "int" is assumed to be 32-bits in size
@@ -124,6 +126,10 @@ Additional information:
   #define STRLEN(a)                                       strlen((a))
 #endif
 
+#ifndef   STRCPY
+  #define STRCPY(pDest, pSrc, NumBytes)                   strcpy((pDest), (pSrc))
+#endif
+
 #ifndef   SEGGER_RTT_MEMCPY_USE_BYTELOOP
   #define SEGGER_RTT_MEMCPY_USE_BYTELOOP                  0
 #endif
@@ -240,7 +246,7 @@ SEGGER_RTT_PUT_CB_SECTION(SEGGER_RTT_CB_ALIGN(SEGGER_RTT_CB _SEGGER_RTT));
 SEGGER_RTT_PUT_BUFFER_SECTION(SEGGER_RTT_BUFFER_ALIGN(static char _acUpBuffer  [BUFFER_SIZE_UP]));
 SEGGER_RTT_PUT_BUFFER_SECTION(SEGGER_RTT_BUFFER_ALIGN(static char _acDownBuffer[BUFFER_SIZE_DOWN]));
 
-static char _ActiveTerminal;
+static unsigned char _ActiveTerminal;
 
 /*********************************************************************
 *
@@ -292,8 +298,8 @@ static void _DoInit(void) {
   // Copy Id string in three steps to make sure "SEGGER RTT" is not found
   // in initializer memory (usually flash) by J-Link
   //
-  strcpy(&p->acID[7], "RTT");
-  strcpy(&p->acID[0], "SEGGER");
+  STRCPY(&p->acID[7], "RTT", 9);
+  STRCPY(&p->acID[0], "SEGGER", 7);
   p->acID[6] = ' ';
 }
 
@@ -490,6 +496,105 @@ static unsigned _GetAvailWriteSpace(SEGGER_RTT_BUFFER_UP* pRing) {
 *
 **********************************************************************
 */
+/*********************************************************************
+*
+*       SEGGER_RTT_ReadUpBufferNoLock()
+*
+*  Function description
+*    Reads characters from SEGGER real-time-terminal control block
+*    which have been previously stored by the application.
+*    Do not lock against interrupts and multiple access.
+*    Used to do the same operation that J-Link does, to transfer 
+*    RTT data via other channels, such as TCP/IP or UART.
+*
+*  Parameters
+*    BufferIndex  Index of Up-buffer to be used.
+*    pBuffer      Pointer to buffer provided by target application, to copy characters from RTT-up-buffer to.
+*    BufferSize   Size of the target application buffer.
+*
+*  Return value
+*    Number of bytes that have been read.
+*
+*  Additional information
+*    This function must not be called when J-Link might also do RTT.
+*/
+unsigned SEGGER_RTT_ReadUpBufferNoLock(unsigned BufferIndex, void* pData, unsigned BufferSize) {
+  unsigned                NumBytesRem;
+  unsigned                NumBytesRead;
+  unsigned                RdOff;
+  unsigned                WrOff;
+  unsigned char*          pBuffer;
+  SEGGER_RTT_BUFFER_UP*   pRing;
+#if SEGGER_RTT_MEMCPY_USE_BYTELOOP
+  const char*             pSrc;
+#endif
+  //
+  INIT();
+  pRing = &_SEGGER_RTT.aUp[BufferIndex];
+  pBuffer = (unsigned char*)pData;
+  RdOff = pRing->RdOff;
+  WrOff = pRing->WrOff;
+  NumBytesRead = 0u;
+  //
+  // Read from current read position to wrap-around of buffer, first
+  //
+  if (RdOff > WrOff) {
+    NumBytesRem = pRing->SizeOfBuffer - RdOff;
+    NumBytesRem = MIN(NumBytesRem, BufferSize);
+#if SEGGER_RTT_MEMCPY_USE_BYTELOOP
+    pSrc = pRing->pBuffer + RdOff;
+    NumBytesRead += NumBytesRem;
+    BufferSize   -= NumBytesRem;
+    RdOff        += NumBytesRem;
+    while (NumBytesRem--) {
+      *pBuffer++ = *pSrc++;
+    };
+#else
+    SEGGER_RTT_MEMCPY(pBuffer, pRing->pBuffer + RdOff, NumBytesRem);
+    NumBytesRead += NumBytesRem;
+    pBuffer      += NumBytesRem;
+    BufferSize   -= NumBytesRem;
+    RdOff        += NumBytesRem;
+#endif
+    //
+    // Handle wrap-around of buffer
+    //
+    if (RdOff == pRing->SizeOfBuffer) {
+      RdOff = 0u;
+    }
+  }
+  //
+  // Read remaining items of buffer
+  //
+  NumBytesRem = WrOff - RdOff;
+  NumBytesRem = MIN(NumBytesRem, BufferSize);
+  if (NumBytesRem > 0u) {
+#if SEGGER_RTT_MEMCPY_USE_BYTELOOP
+    pSrc = pRing->pBuffer + RdOff;
+    NumBytesRead += NumBytesRem;
+    BufferSize   -= NumBytesRem;
+    RdOff        += NumBytesRem;
+    while (NumBytesRem--) {
+      *pBuffer++ = *pSrc++;
+    };
+#else
+    SEGGER_RTT_MEMCPY(pBuffer, pRing->pBuffer + RdOff, NumBytesRem);
+    NumBytesRead += NumBytesRem;
+    pBuffer      += NumBytesRem;
+    BufferSize   -= NumBytesRem;
+    RdOff        += NumBytesRem;
+#endif
+  }
+  //
+  // Update read offset of buffer
+  //
+  if (NumBytesRead) {
+    pRing->RdOff = RdOff;
+  }
+  //
+  return NumBytesRead;
+}
+
 /*********************************************************************
 *
 *       SEGGER_RTT_ReadNoLock()
@@ -581,6 +686,47 @@ unsigned SEGGER_RTT_ReadNoLock(unsigned BufferIndex, void* pData, unsigned Buffe
   return NumBytesRead;
 }
 
+/*********************************************************************
+*
+*       SEGGER_RTT_ReadUpBuffer
+*
+*  Function description
+*    Reads characters from SEGGER real-time-terminal control block
+*    which have been previously stored by the application.
+*    Used to do the same operation that J-Link does, to transfer 
+*    RTT data via other channels, such as TCP/IP or UART.
+*
+*  Parameters
+*    BufferIndex  Index of Up-buffer to be used.
+*    pBuffer      Pointer to buffer provided by target application, to copy characters from RTT-up-buffer to.
+*    BufferSize   Size of the target application buffer.
+*
+*  Return value
+*    Number of bytes that have been read.
+*
+*  Additional information
+*    This function must not be called when J-Link might also do RTT.
+*    This function locks against all other RTT operations. I.e. during
+*    the read operation, writing is also locked.
+*    If only one consumer reads from the up buffer, 
+*    call sEGGER_RTT_ReadUpBufferNoLock() instead.
+*/
+unsigned SEGGER_RTT_ReadUpBuffer(unsigned BufferIndex, void* pBuffer, unsigned BufferSize) {
+  unsigned NumBytesRead;
+  //
+  SEGGER_RTT_LOCK();
+  //
+  // Call the non-locking read function
+  //
+  NumBytesRead = SEGGER_RTT_ReadUpBufferNoLock(BufferIndex, pBuffer, BufferSize);
+  //
+  // Finish up.
+  //
+  SEGGER_RTT_UNLOCK();
+  //
+  return NumBytesRead;
+}
+
 /*********************************************************************
 *
 *       SEGGER_RTT_Read
@@ -722,9 +868,12 @@ void SEGGER_RTT_WriteWithOverwriteNoLock(unsigned BufferIndex, const void* pBuff
 *    BufferIndex  Index of "Up"-buffer to be used (e.g. 0 for "Terminal").
 *    pBuffer      Pointer to character array. Does not need to point to a \0 terminated string.
 *    NumBytes     Number of bytes to be stored in the SEGGER RTT control block.
+*                 MUST be > 0!!!
+*                 This is done for performance reasons, so no initial check has do be done.
 *
 *  Return value
-*    Number of bytes which have been stored in the "Up"-buffer.
+*    1: Data has been copied
+*    0: No space, data has not been copied
 *
 *  Notes
 *    (1) If there is not enough space in the "Up"-buffer, all data is dropped.
@@ -732,6 +881,7 @@ void SEGGER_RTT_WriteWithOverwriteNoLock(unsigned BufferIndex, const void* pBuff
 *        and may only be called after RTT has been initialized.
 *        Either by calling SEGGER_RTT_Init() or calling another RTT API function first.
 */
+#if (RTT_USE_ASM == 0)
 unsigned SEGGER_RTT_WriteSkipNoLock(unsigned BufferIndex, const void* pBuffer, unsigned NumBytes) {
   const char*           pData;
   SEGGER_RTT_BUFFER_UP* pRing;
@@ -739,118 +889,134 @@ unsigned SEGGER_RTT_WriteSkipNoLock(unsigned BufferIndex, const void* pBuffer, u
   unsigned              RdOff;
   unsigned              WrOff;
   unsigned              Rem;
-#if SEGGER_RTT_MEMCPY_USE_BYTELOOP
-  char*                 pDst;
-#endif
-
-  pData = (const char *)pBuffer;
   //
-  // Get "to-host" ring buffer and copy some elements into local variables.
+  // Cases:
+  //   1) RdOff <= WrOff => Space until wrap-around is sufficient
+  //   2) RdOff <= WrOff => Space after wrap-around needed (copy in 2 chunks)
+  //   3) RdOff <  WrOff => No space in buf
+  //   4) RdOff >  WrOff => Space is sufficient
+  //   5) RdOff >  WrOff => No space in buf
+  //
+  // 1) is the most common case for large buffers and assuming that J-Link reads the data fast enough
   //
+  pData = (const char *)pBuffer;
   pRing = &_SEGGER_RTT.aUp[BufferIndex];
   RdOff = pRing->RdOff;
   WrOff = pRing->WrOff;
-  //
-  // Handle the most common cases fastest.
-  // Which is:
-  //    RdOff <= WrOff -> Space until wrap around is free.
-  //  AND
-  //    WrOff + NumBytes < SizeOfBuffer -> No Wrap around necessary.
-  //
-  //  OR
-  //
-  //    RdOff > WrOff -> Space until RdOff - 1 is free.
-  //  AND
-  //    WrOff + NumBytes < RdOff -> Data fits into buffer
-  //
-  if (RdOff <= WrOff) {
-    //
-    // Get space until WrOff will be at wrap around.
-    //
-    Avail = pRing->SizeOfBuffer - 1u - WrOff ;
-    if (Avail >= NumBytes) {
-#if SEGGER_RTT_MEMCPY_USE_BYTELOOP
-      pDst = pRing->pBuffer + WrOff;
-      WrOff += NumBytes;
-      while (NumBytes--) {
-        *pDst++ = *pData++;
-      };
-      pRing->WrOff = WrOff;
-#else
-      SEGGER_RTT_MEMCPY(pRing->pBuffer + WrOff, pData, NumBytes);
+  if (RdOff <= WrOff) {                                 // Case 1), 2) or 3)
+    Avail = pRing->SizeOfBuffer - WrOff - 1u;           // Space until wrap-around (assume 1 byte not usable for case that RdOff == 0)
+    if (Avail >= NumBytes) {                            // Case 1)?
+CopyStraight:
+      memcpy(pRing->pBuffer + WrOff, pData, NumBytes);
       pRing->WrOff = WrOff + NumBytes;
-#endif
       return 1;
     }
-    //
-    // If data did not fit into space until wrap around calculate complete space in buffer.
-    //
-    Avail += RdOff;
-    //
-    // If there is still no space for the whole of this output, don't bother.
-    //
-    if (Avail >= NumBytes) {
+    Avail += RdOff;                                     // Space incl. wrap-around
+    if (Avail >= NumBytes) {                            // Case 2? => If not, we have case 3) (does not fit)
+      Rem = pRing->SizeOfBuffer - WrOff;                // Space until end of buffer
+      memcpy(pRing->pBuffer + WrOff, pData, Rem);       // Copy 1st chunk
+      NumBytes -= Rem;
       //
-      //  OK, we have enough space in buffer. Copy in one or 2 chunks
+      // Special case: First check that assumed RdOff == 0 calculated that last element before wrap-around could not be used
+      // But 2nd check (considering space until wrap-around and until RdOff) revealed that RdOff is not 0, so we can use the last element
+      // In this case, we may use a copy straight until buffer end anyway without needing to copy 2 chunks
+      // Therefore, check if 2nd memcpy is necessary at all
       //
-      Rem = pRing->SizeOfBuffer - WrOff;      // Space until end of buffer
-      if (Rem > NumBytes) {
-#if SEGGER_RTT_MEMCPY_USE_BYTELOOP
-        pDst = pRing->pBuffer + WrOff;
-        WrOff += NumBytes;
-        while (NumBytes--) {
-          *pDst++ = *pData++;
-        };
-        pRing->WrOff = WrOff;
-#else
-        SEGGER_RTT_MEMCPY(pRing->pBuffer + WrOff, pData, NumBytes);
-        pRing->WrOff = WrOff + NumBytes;
-#endif
-      } else {
-        //
-        // We reach the end of the buffer, so need to wrap around
-        //
-#if SEGGER_RTT_MEMCPY_USE_BYTELOOP
-        pDst = pRing->pBuffer + WrOff;
-        NumBytes -= Rem;
-        WrOff = NumBytes;
-        do {
-          *pDst++ = *pData++;
-        } while (--Rem);
-        pDst = pRing->pBuffer;
-        while (NumBytes--) {
-          *pDst++ = *pData++;
-        };
-        pRing->WrOff = WrOff;
-#else
-        SEGGER_RTT_MEMCPY(pRing->pBuffer + WrOff, pData, Rem);
-        SEGGER_RTT_MEMCPY(pRing->pBuffer, pData + Rem, NumBytes - Rem);
-        pRing->WrOff = NumBytes - Rem;
-#endif
+      if (NumBytes) {
+        memcpy(pRing->pBuffer, pData + Rem, NumBytes);
       }
+      pRing->WrOff = NumBytes;
       return 1;
     }
-  } else {
+  } else {                                             // Potential case 4)
     Avail = RdOff - WrOff - 1u;
-    if (Avail >= NumBytes) {
-#if SEGGER_RTT_MEMCPY_USE_BYTELOOP
-      pDst = pRing->pBuffer + WrOff;
-      WrOff += NumBytes;
-      while (NumBytes--) {
-        *pDst++ = *pData++;
-      };
-      pRing->WrOff = WrOff;
-#else
-      SEGGER_RTT_MEMCPY(pRing->pBuffer + WrOff, pData, NumBytes);
-      pRing->WrOff = WrOff + NumBytes;
+    if (Avail >= NumBytes) {                           // Case 4)? => If not, we have case 5) (does not fit)
+      goto CopyStraight;
+    }
+  }
+  return 0;     // No space in buffer
+}
 #endif
-      return 1;
+
+/*********************************************************************
+*
+*       SEGGER_RTT_WriteDownBufferNoLock
+*
+*  Function description
+*    Stores a specified number of characters in SEGGER RTT
+*    control block inside a <Down> buffer.
+*    SEGGER_RTT_WriteDownBufferNoLock does not lock the application.
+*    Used to do the same operation that J-Link does, to transfer 
+*    RTT data from other channels, such as TCP/IP or UART.
+*
+*  Parameters
+*    BufferIndex  Index of "Down"-buffer to be used.
+*    pBuffer      Pointer to character array. Does not need to point to a \0 terminated string.
+*    NumBytes     Number of bytes to be stored in the SEGGER RTT control block.
+*
+*  Return value
+*    Number of bytes which have been stored in the "Down"-buffer.
+*
+*  Notes
+*    (1) Data is stored according to buffer flags.
+*    (2) For performance reasons this function does not call Init()
+*        and may only be called after RTT has been initialized.
+*        Either by calling SEGGER_RTT_Init() or calling another RTT API function first.
+*
+*  Additional information
+*    This function must not be called when J-Link might also do RTT.
+*/
+unsigned SEGGER_RTT_WriteDownBufferNoLock(unsigned BufferIndex, const void* pBuffer, unsigned NumBytes) {
+  unsigned                Status;
+  unsigned                Avail;
+  const char*             pData;
+  SEGGER_RTT_BUFFER_UP*   pRing;
+
+  pData = (const char *)pBuffer;
+  //
+  // Get "to-target" ring buffer.
+  // It is save to cast that to a "to-host" buffer. Up and Down buffer differ in volatility of offsets that might be modified by J-Link.
+  //
+  pRing = (SEGGER_RTT_BUFFER_UP*)&_SEGGER_RTT.aDown[BufferIndex];
+  //
+  // How we output depends upon the mode...
+  //
+  switch (pRing->Flags) {
+  case SEGGER_RTT_MODE_NO_BLOCK_SKIP:
+    //
+    // If we are in skip mode and there is no space for the whole
+    // of this output, don't bother.
+    //
+    Avail = _GetAvailWriteSpace(pRing);
+    if (Avail < NumBytes) {
+      Status = 0u;
+    } else {
+      Status = NumBytes;
+      _WriteNoCheck(pRing, pData, NumBytes);
     }
+    break;
+  case SEGGER_RTT_MODE_NO_BLOCK_TRIM:
+    //
+    // If we are in trim mode, trim to what we can output without blocking.
+    //
+    Avail = _GetAvailWriteSpace(pRing);
+    Status = Avail < NumBytes ? Avail : NumBytes;
+    _WriteNoCheck(pRing, pData, Status);
+    break;
+  case SEGGER_RTT_MODE_BLOCK_IF_FIFO_FULL:
+    //
+    // If we are in blocking mode, output everything.
+    //
+    Status = _WriteBlocking(pRing, pData, NumBytes);
+    break;
+  default:
+    Status = 0u;
+    break;
   }
   //
-  // If we reach this point no data has been written
+  // Finish up.
   //
-  return 0;
+  return Status;
 }
 
 /*********************************************************************
@@ -928,6 +1094,48 @@ unsigned SEGGER_RTT_WriteNoLock(unsigned BufferIndex, const void* pBuffer, unsig
   return Status;
 }
 
+/*********************************************************************
+*
+*       SEGGER_RTT_WriteDownBuffer
+*
+*  Function description
+*    Stores a specified number of characters in SEGGER RTT control block in a <Down> buffer.
+*
+*  Parameters
+*    BufferIndex  Index of "Up"-buffer to be used (e.g. 0 for "Terminal").
+*    pBuffer      Pointer to character array. Does not need to point to a \0 terminated string.
+*    NumBytes     Number of bytes to be stored in the SEGGER RTT control block.
+*
+*  Return value
+*    Number of bytes which have been stored in the "Down"-buffer.
+*
+*  Notes
+*    (1) Data is stored according to buffer flags.
+*
+*  Additional information
+*    This function must not be called when J-Link might also do RTT.
+*    This function locks against all other RTT operations. I.e. during
+*    the write operation, writing from the application is also locked.
+*    If only one consumer writes to the down buffer, 
+*    call SEGGER_RTT_WriteDownBufferNoLock() instead.
+*/
+unsigned SEGGER_RTT_WriteDownBuffer(unsigned BufferIndex, const void* pBuffer, unsigned NumBytes) {
+  unsigned Status;
+  //
+  INIT();
+  SEGGER_RTT_LOCK();
+  //
+  // Call the non-locking write function
+  //
+  Status = SEGGER_RTT_WriteDownBufferNoLock(BufferIndex, pBuffer, NumBytes);
+  //
+  // Finish up.
+  //
+  SEGGER_RTT_UNLOCK();
+  //
+  return Status;
+}
+
 /*********************************************************************
 *
 *       SEGGER_RTT_Write
@@ -1620,7 +1828,7 @@ void SEGGER_RTT_Init (void) {
 *    >= 0  O.K.
 *     < 0  Error (e.g. if RTT is configured for non-blocking mode and there was no space in the buffer to set the new terminal Id)
 */
-int SEGGER_RTT_SetTerminal (char TerminalId) {
+int SEGGER_RTT_SetTerminal (unsigned char TerminalId) {
   unsigned char         ac[2];
   SEGGER_RTT_BUFFER_UP* pRing;
   unsigned Avail;
@@ -1630,8 +1838,8 @@ int SEGGER_RTT_SetTerminal (char TerminalId) {
   //
   r = 0;
   ac[0] = 0xFFu;
-  if ((unsigned char)TerminalId < (unsigned char)sizeof(_aTerminalId)) { // We only support a certain number of channels
-    ac[1] = _aTerminalId[(unsigned char)TerminalId];
+  if (TerminalId < sizeof(_aTerminalId)) { // We only support a certain number of channels
+    ac[1] = _aTerminalId[TerminalId];
     pRing = &_SEGGER_RTT.aUp[0];    // Buffer 0 is always reserved for terminal I/O, so we can use index 0 here, fixed
     SEGGER_RTT_LOCK();    // Lock to make sure that no other task is writing into buffer, while we are and number of free bytes in buffer does not change downwards after checking and before writing
     if ((pRing->Flags & SEGGER_RTT_MODE_MASK) == SEGGER_RTT_MODE_BLOCK_IF_FIFO_FULL) {
@@ -1670,7 +1878,7 @@ int SEGGER_RTT_SetTerminal (char TerminalId) {
 *     < 0 - Error.
 *
 */
-int SEGGER_RTT_TerminalOut (char TerminalId, const char* s) {
+int SEGGER_RTT_TerminalOut (unsigned char TerminalId, const char* s) {
   int                   Status;
   unsigned              FragLen;
   unsigned              Avail;
@@ -1745,5 +1953,53 @@ int SEGGER_RTT_TerminalOut (char TerminalId, const char* s) {
   return Status;
 }
 
+/*********************************************************************
+*
+*       SEGGER_RTT_GetAvailWriteSpace
+*
+*  Function description
+*    Returns the number of bytes available in the ring buffer.
+*
+*  Parameters
+*    BufferIndex  Index of the up buffer.
+*
+*  Return value
+*    Number of bytes that are free in the selected up buffer.
+*/
+unsigned SEGGER_RTT_GetAvailWriteSpace (unsigned BufferIndex){
+  return _GetAvailWriteSpace(&_SEGGER_RTT.aUp[BufferIndex]);
+}
+
+
+/*********************************************************************
+*
+*       SEGGER_RTT_GetBytesInBuffer()
+*
+*  Function description
+*    Returns the number of bytes currently used in the up buffer.
+*
+*  Parameters
+*    BufferIndex  Index of the up buffer.
+*
+*  Return value
+*    Number of bytes that are used in the buffer.
+*/
+unsigned SEGGER_RTT_GetBytesInBuffer(unsigned BufferIndex) {
+  unsigned RdOff;
+  unsigned WrOff;
+  unsigned r;
+  //
+  // Avoid warnings regarding volatile access order.  It's not a problem
+  // in this case, but dampen compiler enthusiasm.
+  //
+  RdOff = _SEGGER_RTT.aUp[BufferIndex].RdOff;
+  WrOff = _SEGGER_RTT.aUp[BufferIndex].WrOff;
+  if (RdOff <= WrOff) {
+    r = WrOff - RdOff;
+  } else {
+    r = _SEGGER_RTT.aUp[BufferIndex].SizeOfBuffer - (WrOff - RdOff);
+  }
+  return r;
+}
 
 /*************************** End of file ****************************/

lib/segger_rtt/SEGGER_RTT.h → lib/SEGGER_RTT/RTT/SEGGER_RTT.h

@@ -3,32 +3,34 @@
 *                        The Embedded Experts                        *
 **********************************************************************
 *                                                                    *
-*            (c) 2014 - 2018 SEGGER Microcontroller GmbH             *
+*            (c) 1995 - 2019 SEGGER Microcontroller GmbH             *
 *                                                                    *
-*           www.segger.com     Support: support@segger.com           *
+*       www.segger.com     Support: support@segger.com               *
+*                                                                    *
+**********************************************************************
+*                                                                    *
+*       SEGGER RTT * Real Time Transfer for embedded targets         *
 *                                                                    *
 **********************************************************************
 *                                                                    *
 * All rights reserved.                                               *
 *                                                                    *
+* SEGGER strongly recommends to not make any changes                 *
+* to or modify the source code of this software in order to stay     *
+* compatible with the RTT protocol and J-Link.                       *
+*                                                                    *
 * Redistribution and use in source and binary forms, with or         *
 * without modification, are permitted provided that the following    *
-* conditions are met:                                                *
+* condition is met:                                                  *
 *                                                                    *
-* - Redistributions of source code must retain the above copyright   *
-*   notice, this list of conditions and the following disclaimer.    *
-*                                                                    *
-* - Neither the name of SEGGER Microcontroller GmbH                  *
-*   nor the names of its contributors may be used to endorse or      *
-*   promote products derived from this software without specific     *
-*   prior written permission.                                        *
+* o Redistributions of source code must retain the above copyright   *
+*   notice, this condition and the following disclaimer.             *
 *                                                                    *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND             *
 * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,        *
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF           *
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE           *
-* DISCLAIMED.                                                        *
-* IN NO EVENT SHALL SEGGER Microcontroller GmbH BE LIABLE FOR        *
+* DISCLAIMED. IN NO EVENT SHALL SEGGER Microcontroller BE LIABLE FOR *
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR           *
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT  *
 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;    *
@@ -44,7 +46,7 @@ File    : SEGGER_RTT.h
 Purpose : Implementation of SEGGER real-time transfer which allows
           real-time communication on targets which support debugger 
           memory accesses while the CPU is running.
-Revision: $Rev: 12804 $
+Revision: $Rev: 17697 $
 ----------------------------------------------------------------------
 */
 
@@ -52,6 +54,63 @@ Revision: $Rev: 12804 $
 #define SEGGER_RTT_H
 
 #include "SEGGER_RTT_Conf.h"
+
+
+
+/*********************************************************************
+*
+*       Defines, defaults
+*
+**********************************************************************
+*/
+#ifndef RTT_USE_ASM
+  #if (defined __SES_ARM)                       // SEGGER Embedded Studio
+    #define _CC_HAS_RTT_ASM_SUPPORT 1
+  #elif (defined __CROSSWORKS_ARM)              // Rowley Crossworks
+    #define _CC_HAS_RTT_ASM_SUPPORT 1
+  #elif (defined __GNUC__)                      // GCC
+    #define _CC_HAS_RTT_ASM_SUPPORT 1
+  #elif (defined __clang__)                     // Clang compiler
+    #define _CC_HAS_RTT_ASM_SUPPORT 1
+  #elif (defined __IASMARM__)                   // IAR assembler
+    #define _CC_HAS_RTT_ASM_SUPPORT 1
+  #elif (defined __ICCARM__)                    // IAR compiler
+    #define _CC_HAS_RTT_ASM_SUPPORT 1
+  #else
+    #define _CC_HAS_RTT_ASM_SUPPORT 0
+  #endif
+  #if (defined __ARM_ARCH_7M__)                 // Cortex-M3/4
+    #define _CORE_HAS_RTT_ASM_SUPPORT 1
+  #elif (defined __ARM_ARCH_7EM__)              // Cortex-M7
+    #define _CORE_HAS_RTT_ASM_SUPPORT 1
+  #elif (defined __ARM_ARCH_8M_MAIN__)          // Cortex-M33
+    #define _CORE_HAS_RTT_ASM_SUPPORT 1
+  #elif (defined __ARM7M__)                     // IAR Cortex-M3/4
+    #if (__CORE__ == __ARM7M__)
+      #define _CORE_HAS_RTT_ASM_SUPPORT 1
+    #else
+      #define _CORE_HAS_RTT_ASM_SUPPORT 0
+    #endif
+  #elif (defined __ARM7EM__)                    // IAR Cortex-M7
+    #if (__CORE__ == __ARM7EM__)
+      #define _CORE_HAS_RTT_ASM_SUPPORT 1
+    #else
+      #define _CORE_HAS_RTT_ASM_SUPPORT 0
+    #endif
+  #else
+    #define _CORE_HAS_RTT_ASM_SUPPORT 0
+  #endif
+  //
+  // If IDE and core support the ASM version, enable ASM version by default
+  //
+  #if (_CC_HAS_RTT_ASM_SUPPORT && _CORE_HAS_RTT_ASM_SUPPORT)
+    #define RTT_USE_ASM                           (1)
+  #else
+    #define RTT_USE_ASM                           (0)
+  #endif
+#endif
+
+#ifndef SEGGER_RTT_ASM  // defined when SEGGER_RTT.h is included from assembly file
 #include <stdlib.h>
 #include <stdarg.h>
 
@@ -144,24 +203,44 @@ int          SEGGER_RTT_WaitKey                 (void);
 unsigned     SEGGER_RTT_Write                   (unsigned BufferIndex, const void* pBuffer, unsigned NumBytes);
 unsigned     SEGGER_RTT_WriteNoLock             (unsigned BufferIndex, const void* pBuffer, unsigned NumBytes);
 unsigned     SEGGER_RTT_WriteSkipNoLock         (unsigned BufferIndex, const void* pBuffer, unsigned NumBytes);
+unsigned     SEGGER_RTT_ASM_WriteSkipNoLock     (unsigned BufferIndex, const void* pBuffer, unsigned NumBytes);
 unsigned     SEGGER_RTT_WriteString             (unsigned BufferIndex, const char* s);
 void         SEGGER_RTT_WriteWithOverwriteNoLock(unsigned BufferIndex, const void* pBuffer, unsigned NumBytes);
 unsigned     SEGGER_RTT_PutChar                 (unsigned BufferIndex, char c);
 unsigned     SEGGER_RTT_PutCharSkip             (unsigned BufferIndex, char c);
 unsigned     SEGGER_RTT_PutCharSkipNoLock       (unsigned BufferIndex, char c);
+unsigned     SEGGER_RTT_GetAvailWriteSpace      (unsigned BufferIndex);
+unsigned     SEGGER_RTT_GetBytesInBuffer        (unsigned BufferIndex);
 //
 // Function macro for performance optimization
 //
 #define      SEGGER_RTT_HASDATA(n)       (_SEGGER_RTT.aDown[n].WrOff - _SEGGER_RTT.aDown[n].RdOff)
 
+#if RTT_USE_ASM
+  #define SEGGER_RTT_WriteSkipNoLock  SEGGER_RTT_ASM_WriteSkipNoLock
+#endif
+
+/*********************************************************************
+*
+*       RTT transfer functions to send RTT data via other channels.
+*
+**********************************************************************
+*/
+unsigned     SEGGER_RTT_ReadUpBuffer            (unsigned BufferIndex, void* pBuffer, unsigned BufferSize);
+unsigned     SEGGER_RTT_ReadUpBufferNoLock      (unsigned BufferIndex, void* pData, unsigned BufferSize);
+unsigned     SEGGER_RTT_WriteDownBuffer         (unsigned BufferIndex, const void* pBuffer, unsigned NumBytes);
+unsigned     SEGGER_RTT_WriteDownBufferNoLock   (unsigned BufferIndex, const void* pBuffer, unsigned NumBytes);
+
+#define      SEGGER_RTT_HASDATA_UP(n)    (_SEGGER_RTT.aUp[n].WrOff - _SEGGER_RTT.aUp[n].RdOff)
+
 /*********************************************************************
 *
 *       RTT "Terminal" API functions
 *
 **********************************************************************
 */
-int     SEGGER_RTT_SetTerminal        (char TerminalId);
-int     SEGGER_RTT_TerminalOut        (char TerminalId, const char* s);
+int     SEGGER_RTT_SetTerminal        (unsigned char TerminalId);
+int     SEGGER_RTT_TerminalOut        (unsigned char TerminalId, const char* s);
 
 /*********************************************************************
 *
@@ -176,6 +255,8 @@ int SEGGER_RTT_vprintf(unsigned BufferIndex, const char * sFormat, va_list * pPa
   }
 #endif
 
+#endif // ifndef(SEGGER_RTT_ASM)
+
 /*********************************************************************
 *
 *       Defines
@@ -186,10 +267,10 @@ int SEGGER_RTT_vprintf(unsigned BufferIndex, const char * sFormat, va_list * pPa
 //
 // Operating modes. Define behavior if buffer is full (not enough space for entire message)
 //
-#define SEGGER_RTT_MODE_NO_BLOCK_SKIP         (0U)     // Skip. Do not block, output nothing. (Default)
-#define SEGGER_RTT_MODE_NO_BLOCK_TRIM         (1U)     // Trim: Do not block, output as much as fits.
-#define SEGGER_RTT_MODE_BLOCK_IF_FIFO_FULL    (2U)     // Block: Wait until there is space in the buffer.
-#define SEGGER_RTT_MODE_MASK                  (3U)
+#define SEGGER_RTT_MODE_NO_BLOCK_SKIP         (0)     // Skip. Do not block, output nothing. (Default)
+#define SEGGER_RTT_MODE_NO_BLOCK_TRIM         (1)     // Trim: Do not block, output as much as fits.
+#define SEGGER_RTT_MODE_BLOCK_IF_FIFO_FULL    (2)     // Block: Wait until there is space in the buffer.
+#define SEGGER_RTT_MODE_MASK                  (3)
 
 //
 // Control sequences, based on ANSI.

lib/SEGGER_RTT/RTT/SEGGER_RTT_ASM_ARMv7M.S

@@ -0,0 +1,235 @@
+/*********************************************************************
+*                   (c) SEGGER Microcontroller GmbH                  *
+*                        The Embedded Experts                        *
+*                           www.segger.com                           *
+**********************************************************************
+
+-------------------------- END-OF-HEADER -----------------------------
+
+File    : SEGGER_RTT_ASM_ARMv7M.S
+Purpose : Assembler implementation of RTT functions for ARMv7M
+
+Additional information:
+  This module is written to be assembler-independent and works with
+  GCC and clang (Embedded Studio) and IAR.
+*/
+
+#define SEGGER_RTT_ASM      // Used to control processed input from header file
+#include "SEGGER_RTT.h"
+
+/*********************************************************************
+*
+*       Defines, fixed
+*
+**********************************************************************
+*/
+#define _CCIAR   0
+#define _CCCLANG 1
+
+#if (defined __SES_ARM) || (defined __GNUC__) || (defined __clang__)
+  #define _CC_TYPE             _CCCLANG
+  #define _PUB_SYM             .global
+  #define _EXT_SYM             .extern
+  #define _END                 .end
+  #define _WEAK                .weak
+  #define _THUMB_FUNC          .thumb_func
+  #define _THUMB_CODE          .code 16
+  #define _WORD                .word
+  #define _SECTION(Sect, Type, AlignExp) .section Sect ##, "ax"
+  #define _ALIGN(Exp)          .align Exp 
+  #define _PLACE_LITS          .ltorg
+  #define _DATA_SECT_START 
+  #define _C_STARTUP           _start
+  #define _STACK_END           __stack_end__
+  #define _RAMFUNC
+  //
+  // .text     => Link to flash
+  // .fast     => Link to RAM
+  // OtherSect => Usually link to RAM
+  // Alignment is 2^x
+  //
+#elif defined (__IASMARM__)
+  #define _CC_TYPE             _CCIAR
+  #define _PUB_SYM             PUBLIC
+  #define _EXT_SYM             EXTERN
+  #define _END                 END
+  #define _WEAK                _WEAK
+  #define _THUMB_FUNC
+  #define _THUMB_CODE          THUMB
+  #define _WORD                DCD
+  #define _SECTION(Sect, Type, AlignExp) SECTION Sect ## : ## Type ## :REORDER:NOROOT ## (AlignExp)
+  #define _ALIGN(Exp)          alignrom Exp 
+  #define _PLACE_LITS
+  #define _DATA_SECT_START     DATA
+  #define _C_STARTUP           __iar_program_start
+  #define _STACK_END           sfe(CSTACK)
+  #define _RAMFUNC             SECTION_TYPE SHT_PROGBITS, SHF_WRITE | SHF_EXECINSTR
+  //
+  // .text     => Link to flash
+  // .textrw   => Link to RAM
+  // OtherSect => Usually link to RAM
+  // NOROOT    => Allows linker to throw away the function, if not referenced
+  // Alignment is 2^x
+  //
+#endif
+
+#if (_CC_TYPE == _CCIAR)
+        NAME SEGGER_RTT_ASM_ARMv7M
+#else
+        .syntax unified
+#endif
+
+#if defined (RTT_USE_ASM) && (RTT_USE_ASM == 1)
+        #define SHT_PROGBITS 0x1
+
+/*********************************************************************
+*
+*       Public / external symbols
+*
+**********************************************************************
+*/
+
+        _EXT_SYM __aeabi_memcpy
+        _EXT_SYM __aeabi_memcpy4
+        _EXT_SYM _SEGGER_RTT
+
+        _PUB_SYM SEGGER_RTT_ASM_WriteSkipNoLock
+
+/*********************************************************************
+*
+*       SEGGER_RTT_WriteSkipNoLock
+*
+*  Function description
+*    Stores a specified number of characters in SEGGER RTT
+*    control block which is then read by the host.
+*    SEGGER_RTT_WriteSkipNoLock does not lock the application and
+*    skips all data, if the data does not fit into the buffer.
+*
+*  Parameters
+*    BufferIndex  Index of "Up"-buffer to be used (e.g. 0 for "Terminal").
+*    pBuffer      Pointer to character array. Does not need to point to a \0 terminated string.
+*    NumBytes     Number of bytes to be stored in the SEGGER RTT control block.
+*                 MUST be > 0!!!
+*                 This is done for performance reasons, so no initial check has do be done.
+*
+*  Return value
+*    1: Data has been copied
+*    0: No space, data has not been copied
+*
+*  Notes
+*    (1) If there is not enough space in the "Up"-buffer, all data is dropped.
+*    (2) For performance reasons this function does not call Init()
+*        and may only be called after RTT has been initialized.
+*        Either by calling SEGGER_RTT_Init() or calling another RTT API function first.
+*/
+        _SECTION(.text, CODE, 2)
+        _ALIGN(2)
+        _THUMB_FUNC
+SEGGER_RTT_ASM_WriteSkipNoLock:   // unsigned SEGGER_RTT_WriteSkipNoLock(unsigned BufferIndex, const void* pData, unsigned NumBytes) {
+        //
+        // Cases:
+        //   1) RdOff <= WrOff => Space until wrap-around is sufficient
+        //   2) RdOff <= WrOff => Space after wrap-around needed (copy in 2 chunks)
+        //   3) RdOff <  WrOff => No space in buf
+        //   4) RdOff >  WrOff => Space is sufficient
+        //   5) RdOff >  WrOff => No space in buf
+        //
+        // 1) is the most common case for large buffers and assuming that J-Link reads the data fast enough
+        //
+        // Register usage:
+        //   R0 Temporary needed as RdOff, <Tmp> register later on
+        //   R1 pData
+        //   R2 <NumBytes>
+        //   R3 <Tmp> register. Hold free for subroutine calls
+        //   R4 <Rem>
+        //   R5 pRing->pBuffer
+        //   R6 pRing (Points to active struct SEGGER_RTT_BUFFER_DOWN)
+        //   R7 WrOff
+        //
+        PUSH     {R4-R7}
+        ADD      R3,R0,R0, LSL #+1
+        LDR.W    R0,=_SEGGER_RTT                 // pRing = &_SEGGER_RTT.aUp[BufferIndex];
+        ADD      R0,R0,R3, LSL #+3
+        ADD      R6,R0,#+24
+        LDR      R0,[R6, #+16]                   // RdOff = pRing->RdOff;
+        LDR      R7,[R6, #+12]                   // WrOff = pRing->WrOff;
+        LDR      R5,[R6, #+4]                    // pRing->pBuffer
+        CMP      R7,R0
+        BCC.N    _CheckCase4                     // if (RdOff <= WrOff) {                           => Case 1), 2) or 3)
+        //
+        // Handling for case 1, later on identical to case 4
+        //
+        LDR      R3,[R6, #+8]                    //  Avail = pRing->SizeOfBuffer - WrOff - 1u;      => Space until wrap-around (assume 1 byte not usable for case that RdOff == 0)
+        SUBS     R4,R3,R7                        // <Rem> (Used in case we jump into case 2 afterwards)
+        SUBS     R3,R4,#+1                       // <Avail>
+        CMP      R3,R2
+        BCC.N    _CheckCase2                     // if (Avail >= NumBytes) {  => Case 1)?
+_Case4:
+        ADDS     R5,R7,R5                        // pBuffer += WrOff
+        ADDS     R0,R2,R7                        // v = WrOff + NumBytes
+        //
+        // 2x unrolling for the copy loop that is used most of the time
+        // This is a special optimization for small SystemView packets and makes them even faster
+        //
+        _ALIGN(2)
+_LoopCopyStraight:                               // memcpy(pRing->pBuffer + WrOff, pData, NumBytes);
+        LDRB     R3,[R1], #+1
+        STRB     R3,[R5], #+1                    // *pDest++ = *pSrc++
+        SUBS     R2,R2,#+1
+        BEQ      _CSDone
+        LDRB     R3,[R1], #+1
+        STRB     R3,[R5], #+1                    // *pDest++ = *pSrc++
+        SUBS     R2,R2,#+1
+        BNE      _LoopCopyStraight
+_CSDone:
+        STR      R0,[R6, #+12]                   // pRing->WrOff = WrOff + NumBytes;
+        MOVS     R0,#+1
+        POP      {R4-R7}
+        BX       LR                              // Return 1
+_CheckCase2:
+        ADDS     R0,R0,R3                        // Avail += RdOff; => Space incl. wrap-around
+        CMP      R0,R2
+        BCC.N    _Case3                          // if (Avail >= NumBytes) {           => Case 2? => If not, we have case 3) (does not fit)
+        //
+        // Handling for case 2
+        //
+        ADDS     R0,R7,R5                        // v = pRing->pBuffer + WrOff => Do not change pRing->pBuffer here because 2nd chunk needs org. value
+        SUBS     R2,R2,R4                        // NumBytes -= Rem;  (Rem = pRing->SizeOfBuffer - WrOff; => Space until end of buffer)
+_LoopCopyBeforeWrapAround:                       // memcpy(pRing->pBuffer + WrOff, pData, Rem); => Copy 1st chunk
+        LDRB     R3,[R1], #+1
+        STRB     R3,[R0], #+1                    // *pDest++ = *pSrc++
+        SUBS     R4,R4,#+1
+        BNE      _LoopCopyBeforeWrapAround
+        //
+        // Special case: First check that assumed RdOff == 0 calculated that last element before wrap-around could not be used
+        // But 2nd check (considering space until wrap-around and until RdOff) revealed that RdOff is not 0, so we can use the last element
+        // In this case, we may use a copy straight until buffer end anyway without needing to copy 2 chunks
+        // Therefore, check if 2nd memcpy is necessary at all
+        //
+        ADDS     R4,R2,#+0                       // Save <NumBytes> (needed as counter in loop but must be written to <WrOff> after the loop). Also use this inst to update the flags to skip 2nd loop if possible
+        BEQ.N    _No2ChunkNeeded                 // if (NumBytes) {
+_LoopCopyAfterWrapAround:                        // memcpy(pRing->pBuffer, pData + Rem, NumBytes);
+        LDRB     R3,[R1], #+1                    // pData already points to the next src byte due to copy loop increment before this loop
+        STRB     R3,[R5], #+1                    // *pDest++ = *pSrc++
+        SUBS     R2,R2,#+1
+        BNE      _LoopCopyAfterWrapAround
+_No2ChunkNeeded:
+        STR      R4,[R6, #+12]                   // pRing->WrOff = NumBytes; => Must be written after copying data because J-Link may read control block asynchronously while writing into buffer
+        MOVS     R0,#+1
+        POP      {R4-R7}
+        BX       LR                              // Return 1
+_CheckCase4:
+        SUBS     R0,R0,R7
+        SUBS     R0,R0,#+1                       // Avail = RdOff - WrOff - 1u;
+        CMP      R0,R2
+        BCS.N    _Case4                          // if (Avail >= NumBytes) {      => Case 4) == 1) ? => If not, we have case 5) == 3) (does not fit)
+_Case3:
+        MOVS     R0,#+0
+        POP      {R4-R7}
+        BX       LR                              // Return 0
+        _PLACE_LITS
+
+#endif  // defined (RTT_USE_ASM) && (RTT_USE_ASM == 1)
+        _END
+
+/*************************** End of file ****************************/

lib/segger_rtt/SEGGER_RTT_Conf.h → lib/SEGGER_RTT/RTT/SEGGER_RTT_Conf.h

@@ -3,32 +3,34 @@
 *                        The Embedded Experts                        *
 **********************************************************************
 *                                                                    *
-*            (c) 2014 - 2018 SEGGER Microcontroller GmbH             *
+*            (c) 1995 - 2019 SEGGER Microcontroller GmbH             *
 *                                                                    *
-*           www.segger.com     Support: support@segger.com           *
+*       www.segger.com     Support: support@segger.com               *
+*                                                                    *
+**********************************************************************
+*                                                                    *
+*       SEGGER RTT * Real Time Transfer for embedded targets         *
 *                                                                    *
 **********************************************************************
 *                                                                    *
 * All rights reserved.                                               *
 *                                                                    *
+* SEGGER strongly recommends to not make any changes                 *
+* to or modify the source code of this software in order to stay     *
+* compatible with the RTT protocol and J-Link.                       *
+*                                                                    *
 * Redistribution and use in source and binary forms, with or         *
 * without modification, are permitted provided that the following    *
-* conditions are met:                                                *
-*                                                                    *
-* - Redistributions of source code must retain the above copyright   *
-*   notice, this list of conditions and the following disclaimer.    *
+* condition is met:                                                  *
 *                                                                    *
-* - Neither the name of SEGGER Microcontroller GmbH                  *
-*   nor the names of its contributors may be used to endorse or      *
-*   promote products derived from this software without specific     *
-*   prior written permission.                                        *
+* o Redistributions of source code must retain the above copyright   *
+*   notice, this condition and the following disclaimer.             *
 *                                                                    *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND             *
 * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,        *
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF           *
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE           *
-* DISCLAIMED.                                                        *
-* IN NO EVENT SHALL SEGGER Microcontroller GmbH BE LIABLE FOR        *
+* DISCLAIMED. IN NO EVENT SHALL SEGGER Microcontroller BE LIABLE FOR *
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR           *
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT  *
 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;    *
@@ -44,7 +46,7 @@ File    : SEGGER_RTT_Conf.h
 Purpose : Implementation of SEGGER real-time transfer (RTT) which
           allows real-time communication on targets which support
           debugger memory accesses while the CPU is running.
-Revision: $Rev: 12804 $
+Revision: $Rev: 18601 $
 
 */
 
@@ -61,16 +63,29 @@ Revision: $Rev: 12804 $
 *
 **********************************************************************
 */
+#ifndef   SEGGER_RTT_MAX_NUM_UP_BUFFERS
+  #define SEGGER_RTT_MAX_NUM_UP_BUFFERS             (3)     // Max. number of up-buffers (T->H) available on this target    (Default: 3)
+#endif
 
-#define SEGGER_RTT_MAX_NUM_UP_BUFFERS             (2)     // Max. number of up-buffers (T->H) available on this target    (Default: 2)
-#define SEGGER_RTT_MAX_NUM_DOWN_BUFFERS           (2)     // Max. number of down-buffers (H->T) available on this target  (Default: 2)
+#ifndef   SEGGER_RTT_MAX_NUM_DOWN_BUFFERS
+  #define SEGGER_RTT_MAX_NUM_DOWN_BUFFERS           (3)     // Max. number of down-buffers (H->T) available on this target  (Default: 3)
+#endif
 
-#define BUFFER_SIZE_UP                            (1024)  // Size of the buffer for terminal output of target, up to host (Default: 1k)
-#define BUFFER_SIZE_DOWN                          (16)    // Size of the buffer for terminal input to target from host (Usually keyboard input) (Default: 16)
+#ifndef   BUFFER_SIZE_UP
+  #define BUFFER_SIZE_UP                            (1024)  // Size of the buffer for terminal output of target, up to host (Default: 1k)
+#endif
 
-#define SEGGER_RTT_PRINTF_BUFFER_SIZE             (64u)    // Size of buffer for RTT printf to bulk-send chars via RTT     (Default: 64)
+#ifndef   BUFFER_SIZE_DOWN
+  #define BUFFER_SIZE_DOWN                          (16)    // Size of the buffer for terminal input to target from host (Usually keyboard input) (Default: 16)
+#endif
 
-#define SEGGER_RTT_MODE_DEFAULT                   SEGGER_RTT_MODE_NO_BLOCK_SKIP // Mode for pre-initialized terminal channel (buffer 0)
+#ifndef   SEGGER_RTT_PRINTF_BUFFER_SIZE
+  #define SEGGER_RTT_PRINTF_BUFFER_SIZE             (64u)    // Size of buffer for RTT printf to bulk-send chars via RTT     (Default: 64)
+#endif
+
+#ifndef   SEGGER_RTT_MODE_DEFAULT
+  #define SEGGER_RTT_MODE_DEFAULT                   SEGGER_RTT_MODE_NO_BLOCK_SKIP // Mode for pre-initialized terminal channel (buffer 0)
+#endif
 
 /*********************************************************************
 *
@@ -84,7 +99,9 @@ Revision: $Rev: 12804 $
 *       This is may be required with memory access restrictions, 
 *       such as on Cortex-A devices with MMU.
 */
-#define SEGGER_RTT_MEMCPY_USE_BYTELOOP              0 // 0: Use memcpy/SEGGER_RTT_MEMCPY, 1: Use a simple byte-loop
+#ifndef   SEGGER_RTT_MEMCPY_USE_BYTELOOP
+  #define SEGGER_RTT_MEMCPY_USE_BYTELOOP              0 // 0: Use memcpy/SEGGER_RTT_MEMCPY, 1: Use a simple byte-loop
+#endif
 //
 // Example definition of SEGGER_RTT_MEMCPY to external memcpy with GCC toolchains and Cortex-A targets
 //
@@ -106,15 +123,16 @@ Revision: $Rev: 12804 $
 // In case of doubt mask all interrupts: 1 << (8 - BASEPRI_PRIO_BITS) i.e. 1 << 5 when 3 bits are implemented in NVIC
 // or define SEGGER_RTT_LOCK() to completely disable interrupts.
 //
-
-#define SEGGER_RTT_MAX_INTERRUPT_PRIORITY         (0x20)   // Interrupt priority to lock on SEGGER_RTT_LOCK on Cortex-M3/4 (Default: 0x20)
+#ifndef   SEGGER_RTT_MAX_INTERRUPT_PRIORITY
+  #define SEGGER_RTT_MAX_INTERRUPT_PRIORITY         (0x20)   // Interrupt priority to lock on SEGGER_RTT_LOCK on Cortex-M3/4 (Default: 0x20)
+#endif
 
 /*********************************************************************
 *
 *       RTT lock configuration for SEGGER Embedded Studio,
 *       Rowley CrossStudio and GCC
 */
-#if (defined __SES_ARM) || (defined __CROSSWORKS_ARM) || (defined __GNUC__) || (defined __clang__)
+#if ((defined(__SES_ARM) || defined(__SES_RISCV) || defined(__CROSSWORKS_ARM) || defined(__GNUC__) || defined(__clang__)) && !defined (__CC_ARM) && !defined(WIN32))
   #if (defined(__ARM_ARCH_6M__) || defined(__ARM_ARCH_8M_BASE__))
     #define SEGGER_RTT_LOCK()   {                                                                   \
                                     unsigned int LockState;                                         \
@@ -176,7 +194,26 @@ Revision: $Rev: 12804 $
                                                 : "r0", "r1"                   \
                                                 );                             \
                             }
-#else
+  #elif defined(__riscv) || defined(__riscv_xlen)
+    #define SEGGER_RTT_LOCK()  {                                               \
+                                 unsigned int LockState;                       \
+                                 __asm volatile ("csrr  %0, mstatus  \n\t"     \
+                                                 "csrci mstatus, 8   \n\t"     \
+                                                 "andi  %0, %0,  8   \n\t"     \
+                                                 : "=r" (LockState)            \
+                                                 :                             \
+                                                 :                             \
+                                                );
+                               
+  #define SEGGER_RTT_UNLOCK()    __asm volatile ("csrr  a1, mstatus  \n\t"     \
+                                                 "or    %0, %0, a1   \n\t"     \
+                                                 "csrs  mstatus, %0  \n\t"     \
+                                                 :                             \
+                                                 : "r"  (LockState)            \
+                                                 : "a1"                        \
+                                                );                             \
+                               }
+  #else
     #define SEGGER_RTT_LOCK()
     #define SEGGER_RTT_UNLOCK()
   #endif
@@ -187,7 +224,8 @@ Revision: $Rev: 12804 $
 *       RTT lock configuration for IAR EWARM
 */
 #ifdef __ICCARM__
-  #if (defined (__ARM6M__) && (__CORE__ == __ARM6M__))
+  #if (defined (__ARM6M__)          && (__CORE__ == __ARM6M__))             ||                      \
+      (defined (__ARM8M_BASELINE__) && (__CORE__ == __ARM8M_BASELINE__))
     #define SEGGER_RTT_LOCK()   {                                                                   \
                                   unsigned int LockState;                                           \
                                   LockState = __get_PRIMASK();                                      \
@@ -195,7 +233,10 @@ Revision: $Rev: 12804 $
 
     #define SEGGER_RTT_UNLOCK()   __set_PRIMASK(LockState);                                         \
                                 }
-  #elif ((defined (__ARM7EM__) && (__CORE__ == __ARM7EM__)) || (defined (__ARM7M__) && (__CORE__ == __ARM7M__)))
+  #elif (defined (__ARM7EM__)         && (__CORE__ == __ARM7EM__))          ||                      \
+        (defined (__ARM7M__)          && (__CORE__ == __ARM7M__))           ||                      \
+        (defined (__ARM8M_MAINLINE__) && (__CORE__ == __ARM8M_MAINLINE__))  ||                      \
+        (defined (__ARM8M_MAINLINE__) && (__CORE__ == __ARM8M_MAINLINE__))
     #ifndef   SEGGER_RTT_MAX_INTERRUPT_PRIORITY
       #define SEGGER_RTT_MAX_INTERRUPT_PRIORITY   (0x20)
     #endif
@@ -296,6 +337,37 @@ Revision: $Rev: 12804 $
   #endif
 #endif
 
+/*********************************************************************
+*
+*       RTT lock configuration for CCRX
+*/
+#ifdef __RX
+  #define SEGGER_RTT_LOCK()   {                                                                     \
+                                unsigned long LockState;                                            \
+                                LockState = get_psw() & 0x010000;                                   \
+                                clrpsw_i();                           
+                                    
+  #define SEGGER_RTT_UNLOCK()   set_psw(get_psw() | LockState);                                     \
+                              }
+#endif
+
+/*********************************************************************
+*
+*       RTT lock configuration for embOS Simulation on Windows
+*       (Can also be used for generic RTT locking with embOS)
+*/
+#if defined(WIN32) || defined(SEGGER_RTT_LOCK_EMBOS)
+
+void OS_SIM_EnterCriticalSection(void);
+void OS_SIM_LeaveCriticalSection(void);
+
+#define SEGGER_RTT_LOCK()       {                                                                   \
+                                  OS_SIM_EnterCriticalSection();
+
+#define SEGGER_RTT_UNLOCK()       OS_SIM_LeaveCriticalSection();                                    \
+                                }
+#endif
+
 /*********************************************************************
 *
 *       RTT lock configuration fallback

lib/SEGGER_RTT/RTT/SEGGER_RTT_printf.c

@@ -0,0 +1,500 @@
+/*********************************************************************
+*                    SEGGER Microcontroller GmbH                     *
+*                        The Embedded Experts                        *
+**********************************************************************
+*                                                                    *
+*            (c) 1995 - 2019 SEGGER Microcontroller GmbH             *
+*                                                                    *
+*       www.segger.com     Support: support@segger.com               *
+*                                                                    *
+**********************************************************************
+*                                                                    *
+*       SEGGER RTT * Real Time Transfer for embedded targets         *
+*                                                                    *
+**********************************************************************
+*                                                                    *
+* All rights reserved.                                               *
+*                                                                    *
+* SEGGER strongly recommends to not make any changes                 *
+* to or modify the source code of this software in order to stay     *
+* compatible with the RTT protocol and J-Link.                       *
+*                                                                    *
+* Redistribution and use in source and binary forms, with or         *
+* without modification, are permitted provided that the following    *
+* condition is met:                                                  *
+*                                                                    *
+* o Redistributions of source code must retain the above copyright   *
+*   notice, this condition and the following disclaimer.             *
+*                                                                    *
+* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND             *
+* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,        *
+* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF           *
+* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE           *
+* DISCLAIMED. IN NO EVENT SHALL SEGGER Microcontroller BE LIABLE FOR *
+* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR           *
+* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT  *
+* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;    *
+* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF      *
+* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT          *
+* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE  *
+* USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH   *
+* DAMAGE.                                                            *
+*                                                                    *
+**********************************************************************
+---------------------------END-OF-HEADER------------------------------
+File    : SEGGER_RTT_printf.c
+Purpose : Replacement for printf to write formatted data via RTT
+Revision: $Rev: 17697 $
+----------------------------------------------------------------------
+*/
+#include "SEGGER_RTT.h"
+#include "SEGGER_RTT_Conf.h"
+
+/*********************************************************************
+*
+*       Defines, configurable
+*
+**********************************************************************
+*/
+
+#ifndef SEGGER_RTT_PRINTF_BUFFER_SIZE
+  #define SEGGER_RTT_PRINTF_BUFFER_SIZE (64)
+#endif
+
+#include <stdlib.h>
+#include <stdarg.h>
+
+
+#define FORMAT_FLAG_LEFT_JUSTIFY   (1u << 0)
+#define FORMAT_FLAG_PAD_ZERO       (1u << 1)
+#define FORMAT_FLAG_PRINT_SIGN     (1u << 2)
+#define FORMAT_FLAG_ALTERNATE      (1u << 3)
+
+/*********************************************************************
+*
+*       Types
+*
+**********************************************************************
+*/
+
+typedef struct {
+  char*     pBuffer;
+  unsigned  BufferSize;
+  unsigned  Cnt;
+
+  int   ReturnValue;
+
+  unsigned RTTBufferIndex;
+} SEGGER_RTT_PRINTF_DESC;
+
+/*********************************************************************
+*
+*       Function prototypes
+*
+**********************************************************************
+*/
+
+/*********************************************************************
+*
+*       Static code
+*
+**********************************************************************
+*/
+/*********************************************************************
+*
+*       _StoreChar
+*/
+static void _StoreChar(SEGGER_RTT_PRINTF_DESC * p, char c) {
+  unsigned Cnt;
+
+  Cnt = p->Cnt;
+  if ((Cnt + 1u) <= p->BufferSize) {
+    *(p->pBuffer + Cnt) = c;
+    p->Cnt = Cnt + 1u;
+    p->ReturnValue++;
+  }
+  //
+  // Write part of string, when the buffer is full
+  //
+  if (p->Cnt == p->BufferSize) {
+    if (SEGGER_RTT_Write(p->RTTBufferIndex, p->pBuffer, p->Cnt) != p->Cnt) {
+      p->ReturnValue = -1;
+    } else {
+      p->Cnt = 0u;
+    }
+  }
+}
+
+/*********************************************************************
+*
+*       _PrintUnsigned
+*/
+static void _PrintUnsigned(SEGGER_RTT_PRINTF_DESC * pBufferDesc, unsigned v, unsigned Base, unsigned NumDigits, unsigned FieldWidth, unsigned FormatFlags) {
+  static const char _aV2C[16] = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };
+  unsigned Div;
+  unsigned Digit;
+  unsigned Number;
+  unsigned Width;
+  char c;
+
+  Number = v;
+  Digit = 1u;
+  //
+  // Get actual field width
+  //
+  Width = 1u;
+  while (Number >= Base) {
+    Number = (Number / Base);
+    Width++;
+  }
+  if (NumDigits > Width) {
+    Width = NumDigits;
+  }
+  //
+  // Print leading chars if necessary
+  //
+  if ((FormatFlags & FORMAT_FLAG_LEFT_JUSTIFY) == 0u) {
+    if (FieldWidth != 0u) {
+      if (((FormatFlags & FORMAT_FLAG_PAD_ZERO) == FORMAT_FLAG_PAD_ZERO) && (NumDigits == 0u)) {
+        c = '0';
+      } else {
+        c = ' ';
+      }
+      while ((FieldWidth != 0u) && (Width < FieldWidth)) {
+        FieldWidth--;
+        _StoreChar(pBufferDesc, c);
+        if (pBufferDesc->ReturnValue < 0) {
+          break;
+        }
+      }
+    }
+  }
+  if (pBufferDesc->ReturnValue >= 0) {
+    //
+    // Compute Digit.
+    // Loop until Digit has the value of the highest digit required.
+    // Example: If the output is 345 (Base 10), loop 2 times until Digit is 100.
+    //
+    while (1) {
+      if (NumDigits > 1u) {       // User specified a min number of digits to print? => Make sure we loop at least that often, before checking anything else (> 1 check avoids problems with NumDigits being signed / unsigned)
+        NumDigits--;
+      } else {
+        Div = v / Digit;
+        if (Div < Base) {        // Is our divider big enough to extract the highest digit from value? => Done
+          break;
+        }
+      }
+      Digit *= Base;
+    }
+    //
+    // Output digits
+    //
+    do {
+      Div = v / Digit;
+      v -= Div * Digit;
+      _StoreChar(pBufferDesc, _aV2C[Div]);
+      if (pBufferDesc->ReturnValue < 0) {
+        break;
+      }
+      Digit /= Base;
+    } while (Digit);
+    //
+    // Print trailing spaces if necessary
+    //
+    if ((FormatFlags & FORMAT_FLAG_LEFT_JUSTIFY) == FORMAT_FLAG_LEFT_JUSTIFY) {
+      if (FieldWidth != 0u) {
+        while ((FieldWidth != 0u) && (Width < FieldWidth)) {
+          FieldWidth--;
+          _StoreChar(pBufferDesc, ' ');
+          if (pBufferDesc->ReturnValue < 0) {
+            break;
+          }
+        }
+      }
+    }
+  }
+}
+
+/*********************************************************************
+*
+*       _PrintInt
+*/
+static void _PrintInt(SEGGER_RTT_PRINTF_DESC * pBufferDesc, int v, unsigned Base, unsigned NumDigits, unsigned FieldWidth, unsigned FormatFlags) {
+  unsigned Width;
+  int Number;
+
+  Number = (v < 0) ? -v : v;
+
+  //
+  // Get actual field width
+  //
+  Width = 1u;
+  while (Number >= (int)Base) {
+    Number = (Number / (int)Base);
+    Width++;
+  }
+  if (NumDigits > Width) {
+    Width = NumDigits;
+  }
+  if ((FieldWidth > 0u) && ((v < 0) || ((FormatFlags & FORMAT_FLAG_PRINT_SIGN) == FORMAT_FLAG_PRINT_SIGN))) {
+    FieldWidth--;
+  }
+
+  //
+  // Print leading spaces if necessary
+  //
+  if ((((FormatFlags & FORMAT_FLAG_PAD_ZERO) == 0u) || (NumDigits != 0u)) && ((FormatFlags & FORMAT_FLAG_LEFT_JUSTIFY) == 0u)) {
+    if (FieldWidth != 0u) {
+      while ((FieldWidth != 0u) && (Width < FieldWidth)) {
+        FieldWidth--;
+        _StoreChar(pBufferDesc, ' ');
+        if (pBufferDesc->ReturnValue < 0) {
+          break;
+        }
+      }
+    }
+  }
+  //
+  // Print sign if necessary
+  //
+  if (pBufferDesc->ReturnValue >= 0) {
+    if (v < 0) {
+      v = -v;
+      _StoreChar(pBufferDesc, '-');
+    } else if ((FormatFlags & FORMAT_FLAG_PRINT_SIGN) == FORMAT_FLAG_PRINT_SIGN) {
+      _StoreChar(pBufferDesc, '+');
+    } else {
+
+    }
+    if (pBufferDesc->ReturnValue >= 0) {
+      //
+      // Print leading zeros if necessary
+      //
+      if (((FormatFlags & FORMAT_FLAG_PAD_ZERO) == FORMAT_FLAG_PAD_ZERO) && ((FormatFlags & FORMAT_FLAG_LEFT_JUSTIFY) == 0u) && (NumDigits == 0u)) {
+        if (FieldWidth != 0u) {
+          while ((FieldWidth != 0u) && (Width < FieldWidth)) {
+            FieldWidth--;
+            _StoreChar(pBufferDesc, '0');
+            if (pBufferDesc->ReturnValue < 0) {
+              break;
+            }
+          }
+        }
+      }
+      if (pBufferDesc->ReturnValue >= 0) {
+        //
+        // Print number without sign
+        //
+        _PrintUnsigned(pBufferDesc, (unsigned)v, Base, NumDigits, FieldWidth, FormatFlags);
+      }
+    }
+  }
+}
+
+/*********************************************************************
+*
+*       Public code
+*
+**********************************************************************
+*/
+/*********************************************************************
+*
+*       SEGGER_RTT_vprintf
+*
+*  Function description
+*    Stores a formatted string in SEGGER RTT control block.
+*    This data is read by the host.
+*
+*  Parameters
+*    BufferIndex  Index of "Up"-buffer to be used. (e.g. 0 for "Terminal")
+*    sFormat      Pointer to format string
+*    pParamList   Pointer to the list of arguments for the format string
+*
+*  Return values
+*    >= 0:  Number of bytes which have been stored in the "Up"-buffer.
+*     < 0:  Error
+*/
+int SEGGER_RTT_vprintf(unsigned BufferIndex, const char * sFormat, va_list * pParamList) {
+  char c;
+  SEGGER_RTT_PRINTF_DESC BufferDesc;
+  int v;
+  unsigned NumDigits;
+  unsigned FormatFlags;
+  unsigned FieldWidth;
+  char acBuffer[SEGGER_RTT_PRINTF_BUFFER_SIZE];
+
+  BufferDesc.pBuffer        = acBuffer;
+  BufferDesc.BufferSize     = SEGGER_RTT_PRINTF_BUFFER_SIZE;
+  BufferDesc.Cnt            = 0u;
+  BufferDesc.RTTBufferIndex = BufferIndex;
+  BufferDesc.ReturnValue    = 0;
+
+  do {
+    c = *sFormat;
+    sFormat++;
+    if (c == 0u) {
+      break;
+    }
+    if (c == '%') {
+      //
+      // Filter out flags
+      //
+      FormatFlags = 0u;
+      v = 1;
+      do {
+        c = *sFormat;
+        switch (c) {
+        case '-': FormatFlags |= FORMAT_FLAG_LEFT_JUSTIFY; sFormat++; break;
+        case '0': FormatFlags |= FORMAT_FLAG_PAD_ZERO;     sFormat++; break;
+        case '+': FormatFlags |= FORMAT_FLAG_PRINT_SIGN;   sFormat++; break;
+        case '#': FormatFlags |= FORMAT_FLAG_ALTERNATE;    sFormat++; break;
+        default:  v = 0; break;
+        }
+      } while (v);
+      //
+      // filter out field with
+      //
+      FieldWidth = 0u;
+      do {
+        c = *sFormat;
+        if ((c < '0') || (c > '9')) {
+          break;
+        }
+        sFormat++;
+        FieldWidth = (FieldWidth * 10u) + ((unsigned)c - '0');
+      } while (1);
+
+      //
+      // Filter out precision (number of digits to display)
+      //
+      NumDigits = 0u;
+      c = *sFormat;
+      if (c == '.') {
+        sFormat++;
+        do {
+          c = *sFormat;
+          if ((c < '0') || (c > '9')) {
+            break;
+          }
+          sFormat++;
+          NumDigits = NumDigits * 10u + ((unsigned)c - '0');
+        } while (1);
+      }
+      //
+      // Filter out length modifier
+      //
+      c = *sFormat;
+      do {
+        if ((c == 'l') || (c == 'h')) {
+          sFormat++;
+          c = *sFormat;
+        } else {
+          break;
+        }
+      } while (1);
+      //
+      // Handle specifiers
+      //
+      switch (c) {
+      case 'c': {
+        char c0;
+        v = va_arg(*pParamList, int);
+        c0 = (char)v;
+        _StoreChar(&BufferDesc, c0);
+        break;
+      }
+      case 'd':
+        v = va_arg(*pParamList, int);
+        _PrintInt(&BufferDesc, v, 10u, NumDigits, FieldWidth, FormatFlags);
+        break;
+      case 'u':
+        v = va_arg(*pParamList, int);
+        _PrintUnsigned(&BufferDesc, (unsigned)v, 10u, NumDigits, FieldWidth, FormatFlags);
+        break;
+      case 'x':
+      case 'X':
+        v = va_arg(*pParamList, int);
+        _PrintUnsigned(&BufferDesc, (unsigned)v, 16u, NumDigits, FieldWidth, FormatFlags);
+        break;
+      case 's':
+        {
+          const char * s = va_arg(*pParamList, const char *);
+          do {
+            c = *s;
+            s++;
+            if (c == '\0') {
+              break;
+            }
+           _StoreChar(&BufferDesc, c);
+          } while (BufferDesc.ReturnValue >= 0);
+        }
+        break;
+      case 'p':
+        v = va_arg(*pParamList, int);
+        _PrintUnsigned(&BufferDesc, (unsigned)v, 16u, 8u, 8u, 0u);
+        break;
+      case '%':
+        _StoreChar(&BufferDesc, '%');
+        break;
+      default:
+        break;
+      }
+      sFormat++;
+    } else {
+      _StoreChar(&BufferDesc, c);
+    }
+  } while (BufferDesc.ReturnValue >= 0);
+
+  if (BufferDesc.ReturnValue > 0) {
+    //
+    // Write remaining data, if any
+    //
+    if (BufferDesc.Cnt != 0u) {
+      SEGGER_RTT_Write(BufferIndex, acBuffer, BufferDesc.Cnt);
+    }
+    BufferDesc.ReturnValue += (int)BufferDesc.Cnt;
+  }
+  return BufferDesc.ReturnValue;
+}
+
+/*********************************************************************
+*
+*       SEGGER_RTT_printf
+*
+*  Function description
+*    Stores a formatted string in SEGGER RTT control block.
+*    This data is read by the host.
+*
+*  Parameters
+*    BufferIndex  Index of "Up"-buffer to be used. (e.g. 0 for "Terminal")
+*    sFormat      Pointer to format string, followed by the arguments for conversion
+*
+*  Return values
+*    >= 0:  Number of bytes which have been stored in the "Up"-buffer.
+*     < 0:  Error
+*
+*  Notes
+*    (1) Conversion specifications have following syntax:
+*          %[flags][FieldWidth][.Precision]ConversionSpecifier
+*    (2) Supported flags:
+*          -: Left justify within the field width
+*          +: Always print sign extension for signed conversions
+*          0: Pad with 0 instead of spaces. Ignored when using '-'-flag or precision
+*        Supported conversion specifiers:
+*          c: Print the argument as one char
+*          d: Print the argument as a signed integer
+*          u: Print the argument as an unsigned integer
+*          x: Print the argument as an hexadecimal integer
+*          s: Print the string pointed to by the argument
+*          p: Print the argument as an 8-digit hexadecimal integer. (Argument shall be a pointer to void.)
+*/
+int SEGGER_RTT_printf(unsigned BufferIndex, const char * sFormat, ...) {
+  int r;
+  va_list ParamList;
+
+  va_start(ParamList, sFormat);
+  r = SEGGER_RTT_vprintf(BufferIndex, sFormat, &ParamList);
+  va_end(ParamList);
+  return r;
+}
+/*************************** End of file ****************************/

lib/SEGGER_RTT/Syscalls/SEGGER_RTT_Syscalls_GCC.c

@@ -0,0 +1,120 @@
+/*********************************************************************
+*                    SEGGER Microcontroller GmbH                     *
+*                        The Embedded Experts                        *
+**********************************************************************
+*                                                                    *
+*            (c) 1995 - 2019 SEGGER Microcontroller GmbH             *
+*                                                                    *
+*       www.segger.com     Support: support@segger.com               *
+*                                                                    *
+**********************************************************************
+*                                                                    *
+*       SEGGER RTT * Real Time Transfer for embedded targets         *
+*                                                                    *
+**********************************************************************
+*                                                                    *
+* All rights reserved.                                               *
+*                                                                    *
+* SEGGER strongly recommends to not make any changes                 *
+* to or modify the source code of this software in order to stay     *
+* compatible with the RTT protocol and J-Link.                       *
+*                                                                    *
+* Redistribution and use in source and binary forms, with or         *
+* without modification, are permitted provided that the following    *
+* condition is met:                                                  *
+*                                                                    *
+* o Redistributions of source code must retain the above copyright   *
+*   notice, this condition and the following disclaimer.             *
+*                                                                    *
+* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND             *
+* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,        *
+* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF           *
+* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE           *
+* DISCLAIMED. IN NO EVENT SHALL SEGGER Microcontroller BE LIABLE FOR *
+* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR           *
+* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT  *
+* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;    *
+* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF      *
+* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT          *
+* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE  *
+* USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH   *
+* DAMAGE.                                                            *
+*                                                                    *
+**********************************************************************
+---------------------------END-OF-HEADER------------------------------
+File    : SEGGER_RTT_Syscalls_GCC.c
+Purpose : Low-level functions for using printf() via RTT in GCC.
+          To use RTT for printf output, include this file in your 
+          application.
+Revision: $Rev: 17697 $
+----------------------------------------------------------------------
+*/
+#if (defined __GNUC__) && !(defined __SES_ARM) && !(defined __CROSSWORKS_ARM)
+
+#include <reent.h>  // required for _write_r
+#include "SEGGER_RTT.h"
+
+
+/*********************************************************************
+*
+*       Types
+*
+**********************************************************************
+*/
+//
+// If necessary define the _reent struct 
+// to match the one passed by the used standard library.
+//
+struct _reent;
+
+/*********************************************************************
+*
+*       Function prototypes
+*
+**********************************************************************
+*/
+int _write(int file, char *ptr, int len);
+int _write_r(struct _reent *r, int file, const void *ptr, int len);
+
+/*********************************************************************
+*
+*       Global functions
+*
+**********************************************************************
+*/
+
+/*********************************************************************
+*
+*       _write()
+*
+* Function description
+*   Low-level write function.
+*   libc subroutines will use this system routine for output to all files,
+*   including stdout.
+*   Write data via RTT.
+*/
+int _write(int file, char *ptr, int len) {
+  (void) file;  /* Not used, avoid warning */
+  SEGGER_RTT_Write(0, ptr, len);
+  return len;
+}
+
+/*********************************************************************
+*
+*       _write_r()
+*
+* Function description
+*   Low-level reentrant write function.
+*   libc subroutines will use this system routine for output to all files,
+*   including stdout.
+*   Write data via RTT.
+*/
+int _write_r(struct _reent *r, int file, const void *ptr, int len) {
+  (void) file;  /* Not used, avoid warning */
+  (void) r;     /* Not used, avoid warning */
+  SEGGER_RTT_Write(0, ptr, len);
+  return len;
+}
+
+#endif
+/****** End Of File *************************************************/

lib/SEGGER_RTT/Syscalls/SEGGER_RTT_Syscalls_IAR.c

@@ -0,0 +1,115 @@
+/*********************************************************************
+*                    SEGGER Microcontroller GmbH                     *
+*                        The Embedded Experts                        *
+**********************************************************************
+*                                                                    *
+*            (c) 1995 - 2019 SEGGER Microcontroller GmbH             *
+*                                                                    *
+*       www.segger.com     Support: support@segger.com               *
+*                                                                    *
+**********************************************************************
+*                                                                    *
+*       SEGGER RTT * Real Time Transfer for embedded targets         *
+*                                                                    *
+**********************************************************************
+*                                                                    *
+* All rights reserved.                                               *
+*                                                                    *
+* SEGGER strongly recommends to not make any changes                 *
+* to or modify the source code of this software in order to stay     *
+* compatible with the RTT protocol and J-Link.                       *
+*                                                                    *
+* Redistribution and use in source and binary forms, with or         *
+* without modification, are permitted provided that the following    *
+* condition is met:                                                  *
+*                                                                    *
+* o Redistributions of source code must retain the above copyright   *
+*   notice, this condition and the following disclaimer.             *
+*                                                                    *
+* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND             *
+* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,        *
+* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF           *
+* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE           *
+* DISCLAIMED. IN NO EVENT SHALL SEGGER Microcontroller BE LIABLE FOR *
+* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR           *
+* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT  *
+* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;    *
+* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF      *
+* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT          *
+* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE  *
+* USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH   *
+* DAMAGE.                                                            *
+*                                                                    *
+**********************************************************************
+---------------------------END-OF-HEADER------------------------------
+File    : SEGGER_RTT_Syscalls_IAR.c
+Purpose : Low-level functions for using printf() via RTT in IAR.
+          To use RTT for printf output, include this file in your
+          application and set the Library Configuration to Normal.
+Revision: $Rev: 17697 $
+----------------------------------------------------------------------
+*/
+#ifdef __IAR_SYSTEMS_ICC__
+
+//
+// Since IAR EWARM V8 and EWRX V4, yfuns.h is considered as deprecated and LowLevelIOInterface.h
+// shall be used instead. To not break any compatibility with older compiler versions, we have a
+// version check in here.
+//
+#if ((defined __ICCARM__) && (__VER__ >= 8000000)) || ((defined __ICCRX__)  && (__VER__ >= 400))
+  #include <LowLevelIOInterface.h>
+#else
+  #include <yfuns.h>
+#endif
+
+#include "SEGGER_RTT.h"
+#pragma module_name = "?__write"
+
+/*********************************************************************
+*
+*       Function prototypes
+*
+**********************************************************************
+*/
+size_t __write(int handle, const unsigned char * buffer, size_t size);
+
+/*********************************************************************
+*
+*       Global functions
+*
+**********************************************************************
+*/
+/*********************************************************************
+*
+*       __write()
+*
+* Function description
+*   Low-level write function.
+*   Standard library subroutines will use this system routine
+*   for output to all files, including stdout.
+*   Write data via RTT.
+*/
+size_t __write(int handle, const unsigned char * buffer, size_t size) {
+  (void) handle;  /* Not used, avoid warning */
+  SEGGER_RTT_Write(0, (const char*)buffer, size);
+  return size;
+}
+
+/*********************************************************************
+*
+*       __write_buffered()
+*
+* Function description
+*   Low-level write function.
+*   Standard library subroutines will use this system routine
+*   for output to all files, including stdout.
+*   Write data via RTT.
+*/
+size_t __write_buffered(int handle, const unsigned char * buffer, size_t size) {
+  (void) handle;  /* Not used, avoid warning */
+  SEGGER_RTT_Write(0, (const char*)buffer, size);
+  return size;
+}
+
+#endif
+/****** End Of File *************************************************/

lib/SEGGER_RTT/Syscalls/SEGGER_RTT_Syscalls_KEIL.c

@@ -0,0 +1,386 @@
+/*********************************************************************
+*                    SEGGER Microcontroller GmbH                     *
+*                        The Embedded Experts                        *
+**********************************************************************
+*                                                                    *
+*            (c) 1995 - 2019 SEGGER Microcontroller GmbH             *
+*                                                                    *
+*       www.segger.com     Support: support@segger.com               *
+*                                                                    *
+**********************************************************************
+*                                                                    *
+*       SEGGER RTT * Real Time Transfer for embedded targets         *
+*                                                                    *
+**********************************************************************
+*                                                                    *
+* All rights reserved.                                               *
+*                                                                    *
+* SEGGER strongly recommends to not make any changes                 *
+* to or modify the source code of this software in order to stay     *
+* compatible with the RTT protocol and J-Link.                       *
+*                                                                    *
+* Redistribution and use in source and binary forms, with or         *
+* without modification, are permitted provided that the following    *
+* condition is met:                                                  *
+*                                                                    *
+* o Redistributions of source code must retain the above copyright   *
+*   notice, this condition and the following disclaimer.             *
+*                                                                    *
+* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND             *
+* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,        *
+* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF           *
+* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE           *
+* DISCLAIMED. IN NO EVENT SHALL SEGGER Microcontroller BE LIABLE FOR *
+* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR           *
+* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT  *
+* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;    *
+* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF      *
+* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT          *
+* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE  *
+* USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH   *
+* DAMAGE.                                                            *
+*                                                                    *
+**********************************************************************
+---------------------------END-OF-HEADER------------------------------
+File    : RTT_Syscalls_KEIL.c
+Purpose : Retargeting module for KEIL MDK-CM3.
+          Low-level functions for using printf() via RTT
+Revision: $Rev: 17697 $
+----------------------------------------------------------------------
+*/
+#ifdef __CC_ARM
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <rt_sys.h>
+#include <rt_misc.h>
+
+#include "SEGGER_RTT.h"
+/*********************************************************************
+*
+*       #pragmas
+*
+**********************************************************************
+*/
+#pragma import(__use_no_semihosting)
+
+#ifdef _MICROLIB
+  #pragma import(__use_full_stdio)
+#endif
+
+/*********************************************************************
+*
+*       Defines non-configurable
+*
+**********************************************************************
+*/
+
+/* Standard IO device handles - arbitrary, but any real file system handles must be
+   less than 0x8000. */
+#define STDIN             0x8001    // Standard Input Stream
+#define STDOUT            0x8002    // Standard Output Stream
+#define STDERR            0x8003    // Standard Error Stream
+
+/*********************************************************************
+*
+*       Public const
+*
+**********************************************************************
+*/
+#if __ARMCC_VERSION < 5000000
+//const char __stdin_name[]  = "STDIN";
+const char __stdout_name[] = "STDOUT";
+const char __stderr_name[] = "STDERR";
+#endif
+
+/*********************************************************************
+*
+*       Public code
+*
+**********************************************************************
+*/
+
+/*********************************************************************
+*
+*       _ttywrch
+*
+*  Function description:
+*    Outputs a character to the console
+*
+*  Parameters:
+*    c    - character to output
+*  
+*/
+void _ttywrch(int c) {
+  fputc(c, stdout); // stdout
+  fflush(stdout);
+}
+
+/*********************************************************************
+*
+*       _sys_open
+*
+*  Function description:
+*    Opens the device/file in order to do read/write operations
+*
+*  Parameters:
+*    sName        - sName of the device/file to open
+*    OpenMode    - This parameter is currently ignored
+*  
+*  Return value:
+*    != 0     - Handle to the object to open, otherwise 
+*    == 0     -"device" is not handled by this module
+*
+*/
+FILEHANDLE _sys_open(const char * sName, int OpenMode) {
+  (void)OpenMode;
+  // Register standard Input Output devices.
+  if (strcmp(sName, __stdout_name) == 0) {
+    return (STDOUT);
+  } else if (strcmp(sName, __stderr_name) == 0) {
+    return (STDERR);
+  } else
+  return (0);  // Not implemented
+}
+
+/*********************************************************************
+*
+*       _sys_close
+*
+*  Function description:
+*    Closes the handle to the open device/file
+*
+*  Parameters:
+*    hFile    - Handle to a file opened via _sys_open
+*  
+*  Return value:
+*    0     - device/file closed
+*
+*/
+int _sys_close(FILEHANDLE hFile) {
+  (void)hFile;
+  return 0;  // Not implemented
+}
+
+/*********************************************************************
+*
+*       _sys_write
+*
+*  Function description:
+*    Writes the data to an open handle.
+*    Currently this function only outputs data to the console
+*
+*  Parameters:
+*    hFile    - Handle to a file opened via _sys_open
+*    pBuffer  - Pointer to the data that shall be written
+*    NumBytes      - Number of bytes to write
+*    Mode     - The Mode that shall be used
+*  
+*  Return value:
+*    Number of bytes *not* written to the file/device
+*
+*/
+int _sys_write(FILEHANDLE hFile, const unsigned char * pBuffer, unsigned NumBytes, int Mode) {
+  int r = 0;
+
+  (void)Mode;
+  if (hFile == STDOUT) {
+    SEGGER_RTT_Write(0, (const char*)pBuffer, NumBytes);
+		return 0;
+  }
+  return r;
+}
+
+/*********************************************************************
+*
+*       _sys_read
+*
+*  Function description:
+*    Reads data from an open handle.
+*    Currently this modules does nothing.
+*
+*  Parameters:
+*    hFile    - Handle to a file opened via _sys_open
+*    pBuffer  - Pointer to buffer to store the read data
+*    NumBytes      - Number of bytes to read
+*    Mode     - The Mode that shall be used
+*  
+*  Return value:
+*    Number of bytes read from the file/device
+*
+*/
+int _sys_read(FILEHANDLE hFile, unsigned char * pBuffer, unsigned NumBytes, int Mode) {
+  (void)hFile;
+  (void)pBuffer;
+  (void)NumBytes;
+  (void)Mode;
+  return (0);  // Not implemented
+}
+
+/*********************************************************************
+*
+*       _sys_istty
+*
+*  Function description:
+*    This function shall return whether the opened file 
+*    is a console device or not.
+*
+*  Parameters:
+*    hFile    - Handle to a file opened via _sys_open
+*  
+*  Return value:
+*    1       - Device is     a console
+*    0       - Device is not a console
+*
+*/
+int _sys_istty(FILEHANDLE hFile) {
+  if (hFile > 0x8000) {
+    return (1);
+  }
+  return (0);  // Not implemented
+}
+
+/*********************************************************************
+*
+*       _sys_seek
+*
+*  Function description:
+*    Seeks via the file to a specific position
+*
+*  Parameters:
+*    hFile  - Handle to a file opened via _sys_open
+*    Pos    - 
+*  
+*  Return value:
+*    int       - 
+*
+*/
+int _sys_seek(FILEHANDLE hFile, long Pos) {
+  (void)hFile;
+  (void)Pos;
+  return (0);  // Not implemented
+}
+
+/*********************************************************************
+*
+*       _sys_ensure
+*
+*  Function description:
+*    
+*
+*  Parameters:
+*    hFile    - Handle to a file opened via _sys_open
+*  
+*  Return value:
+*    int       - 
+*
+*/
+int _sys_ensure(FILEHANDLE hFile) {
+  (void)hFile;
+  return (-1);  // Not implemented
+}
+
+/*********************************************************************
+*
+*       _sys_flen
+*
+*  Function description:
+*    Returns the length of the opened file handle
+*
+*  Parameters:
+*    hFile    - Handle to a file opened via _sys_open
+*  
+*  Return value:
+*    Length of the file
+*
+*/
+long _sys_flen(FILEHANDLE hFile) {
+  (void)hFile;
+  return (0);  // Not implemented
+}
+
+/*********************************************************************
+*
+*       _sys_tmpnam
+*
+*  Function description:
+*    This function converts the file number fileno for a temporary 
+*    file to a unique filename, for example, tmp0001.
+*
+*  Parameters:
+*    pBuffer    - Pointer to a buffer to store the name
+*    FileNum    - file number to convert
+*    MaxLen     - Size of the buffer
+*  
+*  Return value:
+*     1 - Error
+*     0 - Success  
+*
+*/
+int _sys_tmpnam(char * pBuffer, int FileNum, unsigned MaxLen) {
+  (void)pBuffer;
+  (void)FileNum;
+  (void)MaxLen;
+  return (1);  // Not implemented
+}
+
+/*********************************************************************
+*
+*       _sys_command_string
+*
+*  Function description:
+*    This function shall execute a system command.
+*
+*  Parameters:
+*    cmd    - Pointer to the command string
+*    len    - Length of the string
+*  
+*  Return value:
+*    == NULL - Command was not successfully executed
+*    == sCmd - Command was passed successfully
+*
+*/
+char * _sys_command_string(char * cmd, int len) {
+  (void)len;
+  return cmd;  // Not implemented
+}
+
+/*********************************************************************
+*
+*       _sys_exit
+*
+*  Function description:
+*    This function is called when the application returns from main
+*
+*  Parameters:
+*    ReturnCode    - Return code from the main function
+*  
+*
+*/
+void _sys_exit(int ReturnCode) {
+  (void)ReturnCode;
+  while (1);  // Not implemented
+}
+
+#if __ARMCC_VERSION >= 5000000
+/*********************************************************************
+*
+*       stdout_putchar
+*
+*  Function description:
+*    Put a character to the stdout
+*
+*  Parameters:
+*    ch    - Character to output
+*  
+*
+*/
+int stdout_putchar(int ch) {
+  (void)ch;
+  return ch;  // Not implemented
+}
+#endif
+
+#endif
+/*************************** End of file ****************************/

lib/SEGGER_RTT/Syscalls/SEGGER_RTT_Syscalls_SES.c

@@ -0,0 +1,247 @@
+/*********************************************************************
+*                    SEGGER Microcontroller GmbH                     *
+*                        The Embedded Experts                        *
+**********************************************************************
+*                                                                    *
+*            (c) 1995 - 2019 SEGGER Microcontroller GmbH             *
+*                                                                    *
+*       www.segger.com     Support: support@segger.com               *
+*                                                                    *
+**********************************************************************
+*                                                                    *
+*       SEGGER RTT * Real Time Transfer for embedded targets         *
+*                                                                    *
+**********************************************************************
+*                                                                    *
+* All rights reserved.                                               *
+*                                                                    *
+* SEGGER strongly recommends to not make any changes                 *
+* to or modify the source code of this software in order to stay     *
+* compatible with the RTT protocol and J-Link.                       *
+*                                                                    *
+* Redistribution and use in source and binary forms, with or         *
+* without modification, are permitted provided that the following    *
+* condition is met:                                                  *
+*                                                                    *
+* o Redistributions of source code must retain the above copyright   *
+*   notice, this condition and the following disclaimer.             *
+*                                                                    *
+* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND             *
+* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,        *
+* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF           *
+* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE           *
+* DISCLAIMED. IN NO EVENT SHALL SEGGER Microcontroller BE LIABLE FOR *
+* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR           *
+* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT  *
+* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;    *
+* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF      *
+* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT          *
+* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE  *
+* USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH   *
+* DAMAGE.                                                            *
+*                                                                    *
+**********************************************************************
+---------------------------END-OF-HEADER------------------------------
+File    : SEGGER_RTT_Syscalls_SES.c
+Purpose : Reimplementation of printf, puts and __getchar using RTT
+          in SEGGER Embedded Studio.
+          To use RTT for printf output, include this file in your
+          application.
+Revision: $Rev: 18539 $
+----------------------------------------------------------------------
+*/
+#if (defined __SES_ARM) || (defined __SES_RISCV) || (defined __CROSSWORKS_ARM)
+
+#include "SEGGER_RTT.h"
+#include <stdarg.h>
+#include <stdio.h>
+#include "limits.h"
+#include "__libc.h"
+#include "__vfprintf.h"
+
+/*********************************************************************
+*
+*       Defines, configurable
+*
+**********************************************************************
+*/
+//
+// Select string formatting implementation.
+//
+// RTT printf formatting
+//  - Configurable stack usage. (SEGGER_RTT_PRINTF_BUFFER_SIZE in SEGGER_RTT_Conf.h)
+//  - No maximum string length.
+//  - Limited conversion specifiers and flags. (See SEGGER_RTT_printf.c)
+// Standard library printf formatting
+//  - Configurable formatting capabilities.
+//  - Full conversion specifier and flag support.
+//  - Maximum string length has to be known or (slightly) slower character-wise output.
+//
+// #define PRINTF_USE_SEGGER_RTT_FORMATTING    0 // Use standard library formatting
+// #define PRINTF_USE_SEGGER_RTT_FORMATTING    1 // Use RTT formatting
+//
+#ifndef   PRINTF_USE_SEGGER_RTT_FORMATTING
+  #define PRINTF_USE_SEGGER_RTT_FORMATTING    0
+#endif
+//
+// If using standard library formatting,
+// select maximum output string buffer size or character-wise output.
+//
+// #define PRINTF_BUFFER_SIZE                  0 // Use character-wise output
+// #define PRINTF_BUFFER_SIZE                128 // Default maximum string length
+//
+#ifndef   PRINTF_BUFFER_SIZE
+  #define PRINTF_BUFFER_SIZE                128
+#endif
+
+#if PRINTF_USE_SEGGER_RTT_FORMATTING  // Use SEGGER RTT formatting implementation
+/*********************************************************************
+*
+*       Function prototypes
+*
+**********************************************************************
+*/
+int SEGGER_RTT_vprintf(unsigned BufferIndex, const char * sFormat, va_list * pParamList);
+
+/*********************************************************************
+*
+*       Global functions, printf
+*
+**********************************************************************
+*/
+/*********************************************************************
+*
+*       printf()
+*
+*  Function description
+*    print a formatted string using RTT and SEGGER RTT formatting.
+*/
+int printf(const char *fmt,...) {
+  int     n;
+  va_list args;
+
+  va_start (args, fmt);
+  n = SEGGER_RTT_vprintf(0, fmt, &args);
+  va_end(args);
+  return n;
+}
+
+#elif PRINTF_BUFFER_SIZE == 0 // Use standard library formatting with character-wise output
+
+/*********************************************************************
+*
+*       Static functions
+*
+**********************************************************************
+*/
+static int _putchar(int x, __printf_tag_ptr ctx) {
+  (void)ctx;
+  SEGGER_RTT_Write(0, (char *)&x, 1);
+  return x;
+}
+
+/*********************************************************************
+*
+*       Global functions, printf
+*
+**********************************************************************
+*/
+/*********************************************************************
+*
+*       printf()
+*
+*  Function description
+*    print a formatted string character-wise, using RTT and standard
+*    library formatting.
+*/
+int printf(const char *fmt, ...) {
+  int         n;
+  va_list     args;
+  __printf_t  iod;
+
+  va_start(args, fmt);
+  iod.string    = 0;
+  iod.maxchars  = INT_MAX;
+  iod.output_fn = _putchar;
+  SEGGER_RTT_LOCK();
+  n = __vfprintf(&iod, fmt, args);
+  SEGGER_RTT_UNLOCK();
+  va_end(args);
+  return n;
+}
+
+#else // Use standard library formatting with static buffer
+
+/*********************************************************************
+*
+*       Global functions, printf
+*
+**********************************************************************
+*/
+/*********************************************************************
+*
+*       printf()
+*
+*  Function description
+*    print a formatted string using RTT and standard library formatting.
+*/
+int printf(const char *fmt,...) {
+  int     n;
+  char    aBuffer[PRINTF_BUFFER_SIZE];
+  va_list args;
+
+  va_start (args, fmt);
+  n = vsnprintf(aBuffer, sizeof(aBuffer), fmt, args);
+  if (n > (int)sizeof(aBuffer)) {
+    SEGGER_RTT_Write(0, aBuffer, sizeof(aBuffer));
+  } else if (n > 0) {
+    SEGGER_RTT_Write(0, aBuffer, n);
+  }
+  va_end(args);
+  return n;
+}
+#endif
+
+/*********************************************************************
+*
+*       Global functions
+*
+**********************************************************************
+*/
+/*********************************************************************
+*
+*       puts()
+*
+*  Function description
+*    print a string using RTT.
+*/
+int puts(const char *s) {
+  return SEGGER_RTT_WriteString(0, s);
+}
+
+/*********************************************************************
+*
+*       __putchar()
+*
+*  Function description
+*    Write one character via RTT.
+*/
+int __putchar(int x, __printf_tag_ptr ctx) {
+  (void)ctx;
+  SEGGER_RTT_Write(0, (char *)&x, 1);
+  return x;
+}
+
+/*********************************************************************
+*
+*       __getchar()
+*
+*  Function description
+*    Wait for and get a character via RTT.
+*/
+int __getchar() {
+  return SEGGER_RTT_WaitKey();
+}
+
+#endif
+/****** End Of File *************************************************/

lib/segger_rtt/SEGGER_RTT_SES.c

@@ -1,79 +0,0 @@
-/*********************************************************************
-*                    SEGGER Microcontroller GmbH                     *
-*                        The Embedded Experts                        *
-**********************************************************************
-*                                                                    *
-*            (c) 2014 - 2018 SEGGER Microcontroller GmbH             *
-*                                                                    *
-*           www.segger.com     Support: support@segger.com           *
-*                                                                    *
-**********************************************************************
-*                                                                    *
-* All rights reserved.                                               *
-*                                                                    *
-* Redistribution and use in source and binary forms, with or         *
-* without modification, are permitted provided that the following    *
-* conditions are met:                                                *
-*                                                                    *
-* - Redistributions of source code must retain the above copyright   *
-*   notice, this list of conditions and the following disclaimer.    *
-*                                                                    *
-* - Neither the name of SEGGER Microcontroller GmbH                  *
-*   nor the names of its contributors may be used to endorse or      *
-*   promote products derived from this software without specific     *
-*   prior written permission.                                        *
-*                                                                    *
-* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND             *
-* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,        *
-* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF           *
-* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE           *
-* DISCLAIMED.                                                        *
-* IN NO EVENT SHALL SEGGER Microcontroller GmbH BE LIABLE FOR        *
-* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR           *
-* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT  *
-* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;    *
-* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF      *
-* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT          *
-* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE  *
-* USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH   *
-* DAMAGE.                                                            *
-*                                                                    *
-**********************************************************************
---------  END-OF-HEADER  ---------------------------------------------
-File    : SEGGER_RTT_Syscalls_SES.c
-Purpose : Reimplementation of printf, puts and 
-          implementation of __putchar and __getchar using RTT in SES.
-          To use RTT for printf output, include this file in your 
-          application.
-----------------------------------------------------------------------
-*/
-#include "SEGGER_RTT.h"
-#include "__libc.h"
-#include <stdarg.h>
-#include <stdio.h>
-
-int printf(const char *fmt,...) {
-  char buffer[128];
-  va_list args;
-  va_start (args, fmt);
-  int n = vsnprintf(buffer, sizeof(buffer), fmt, args);
-  SEGGER_RTT_Write(0, buffer, n);
-  va_end(args);
-  return n;
-}
-
-int puts(const char *s) {
-  return SEGGER_RTT_WriteString(0, s);
-}
-
-int __putchar(int x, __printf_tag_ptr ctx) {
-  (void)ctx;
-  SEGGER_RTT_Write(0, (char *)&x, 1);
-  return x;
-}
-
-int __getchar() {
-  return SEGGER_RTT_WaitKey();
-}
-
-/****** End Of File *************************************************/

src/class/midi/midi_device.c

@@ -88,13 +88,14 @@ bool tud_midi_n_mounted (uint8_t itf)
 static void _prep_out_transaction (midid_interface_t* p_midi)
 {
   // skip if previous transfer not complete
-  if ( usbd_edpt_busy(TUD_OPT_RHPORT, p_midi->ep_out) )
-    return;
+  if ( usbd_edpt_busy(TUD_OPT_RHPORT, p_midi->ep_out) ) return;
 
   // Prepare for incoming data but only allow what we can store in the ring buffer.
   uint16_t max_read = tu_fifo_remaining(&p_midi->rx_ff);
   if ( max_read >= CFG_TUD_MIDI_EPSIZE )
+  {
     usbd_edpt_xfer(TUD_OPT_RHPORT, p_midi->ep_out, p_midi->epout_buf, CFG_TUD_MIDI_EPSIZE);
+  }
 }
 
 //--------------------------------------------------------------------+