Merge pull request #51 from SummerGGift/2018_8_3

【修改】：串口设备找到后没有打开的问题

port/machine_uart.c

@@ -66,6 +66,14 @@ STATIC mp_obj_t machine_uart_make_new(const mp_obj_type_t *type, size_t n_args,
         rt_kprintf("ERROR: UART device %s not found!\n", uart_dev_name);
         nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "UART(%s) doesn't exist", uart_dev_name));
     }
+	
+    rt_err_t result;
+    result = rt_device_open((rt_device_t)rt_serial_device, RT_DEVICE_OFLAG_RDWR);
+    if (result != RT_EOK)
+    {
+        rt_kprintf("ERROR: UART device %s can't open!\n", uart_dev_name);
+        nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "UART(%s) can't open", uart_dev_name));
+    }
 
     // create new uart object
     machine_uart_obj_t *self = m_new_obj(machine_uart_obj_t);
@@ -223,7 +231,7 @@ STATIC mp_uint_t machine_uart_read(mp_obj_t self_in, void *buf_in, mp_uint_t siz
     machine_uart_obj_t *self = self_in;
     byte *buf = buf_in;
     //TODO dfs sync read
-    MP_RTT_NOT_IMPL_PRINT;
+    //MP_RTT_NOT_IMPL_PRINT;
     return rt_device_read((struct rt_device *)(self->uart_device), -1, buf, size);
 }
 
@@ -231,7 +239,7 @@ STATIC mp_uint_t machine_uart_write(mp_obj_t self_in, const void *buf_in, mp_uin
     machine_uart_obj_t *self = self_in;
     const byte *buf = buf_in;
     //TODO dfs sync write
-    MP_RTT_NOT_IMPL_PRINT;
+    //MP_RTT_NOT_IMPL_PRINT;
     return rt_device_write((struct rt_device *)(self->uart_device), -1, buf, size);
 }