Make debug print safer by checking if ST-Link debugger is connected

Core/Src/cansend.c

@@ -111,10 +111,13 @@ void vUARTLogger(void *argument)
       {
         DEBUG_PRINT("CAN frame detected\r\n");
         int len = format_can_message(tx_buffer, message.source, &message);
-        HAL_UART_Transmit_DMA(&huart1, (uint8_t*)tx_buffer, len);
+        if (HAL_UART_Transmit_DMA(&huart1, (uint8_t*)tx_buffer, len) == HAL_OK)
+        {
             osSemaphoreAcquire(xUARTDMASemaphore, osWaitForever);
             DEBUG_PRINT("CAN frame sent via UART\r\n");
         }
+        else DEBUG_PRINT("HAL error, CAN frame NOT sent!\r\n");
+      }
     }
 }
 /* END vUARTLoggerListen */

Core/Src/main.c

@@ -77,10 +77,15 @@ static void MX_SDIO_SD_Init(void);
 static void MX_USART1_UART_Init(void);
 
 /* USER CODE BEGIN PFP */
-int _write(int file, char *ptr, int len) {
+int _write(int file, char *ptr, int len)
- for (int i = 0; i < len; i++) {
+{
+  if ((CoreDebug->DEMCR & CoreDebug_DEMCR_TRCENA_Msk) && (ITM->TCR & ITM_TCR_ITMENA_Msk))
+  {
+    for (int i = 0; i < len; i++)
+    {
       ITM_SendChar((*ptr++));
     }
+  }
   return len;
 }
 /* USER CODE END PFP */