# PIC32 Application using queue crashes **URL:** \ **Category:** Kernel\ **Created:** [November 1, 2012, 2:44pm UTC](https://forums.freertos.org/t/pic32-application-using-queue-crashes/5131 "2012-11-01T14:44:41Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![system](https://d2v6vdsk2p900z.cloudfront.net/original/1X/7fc8fdb729c645aab5b20282bbe34e57cb407be6.jpeg) [@system](https://forums.freertos.org/u/system)\ **Post date:** [November 1, 2012, 2:44pm UTC](https://forums.freertos.org/t/pic32-application-using-queue-crashes/5131/1 "2012-11-01T14:44:41Z")
**[aethamyn](https://sourceforge.net/u/aethamyn/)** wrote on [Thursday, November 01, 2012](https://sourceforge.net/p/freertos/discussion/382005/thread/dfef08af/#d06e): Hi everybody, I am facing a problem with PIC32 port when I try to use queues. I got a simple application, only one task, one queue. There are correctly initialised (task and queue handles aren’t null), vTaskStartScheduler() is called, then my task tries to receive a message from the queue with xQueueReceive(). I get stuck in vListInsert(), but : 1. My stack task doesn’t overflow (I use method 2 for stack checking and vApplicationStackOverflowHook() is never called) 2. I don’t think I have trouble with interrupts priorities : Kernell priority is 1, max interrupt priority is set to 4. Plus, I don’t have used any other interrupts than those used for the kernell. 3. When xQueueReceived() is called, the scheduler is running (xSchedulerRunning = 1 and uxSchedulerSuspended = 0) but in vListInsert(), scheduler is suspended (is that ok ?). Actually it is suspended when calling vTaskSuspendAll in xQueueGenericReceive(). 4. Queue has been initialised, no pending message. Then, a bus exception is thrown (DBE). I have the same problem if I create a second task that put a message into the queue. If it could help, I am using XC32 v1.11. I can reproduce the problem with MPLAB Sim and when I am debugging with a Digilent Cerebot MX7ck board with built-in licensed debugger. ---
**Author:** ![system](https://d2v6vdsk2p900z.cloudfront.net/original/1X/7fc8fdb729c645aab5b20282bbe34e57cb407be6.jpeg) [@system](https://forums.freertos.org/u/system)\ **Post date:** [November 1, 2012, 2:59pm UTC](https://forums.freertos.org/t/pic32-application-using-queue-crashes/5131/2 "2012-11-01T14:59:21Z")
**[davedoors](https://sourceforge.net/u/davedoors/)** wrote on [Thursday, November 01, 2012](https://sourceforge.net/p/freertos/discussion/382005/thread/dfef08af/#0dc9): As your application is so small, please post the code. Make sure to enclose it with the Codify Text tags (button just above the text entry box in the forum). ---
**Author:** ![system](https://d2v6vdsk2p900z.cloudfront.net/original/1X/7fc8fdb729c645aab5b20282bbe34e57cb407be6.jpeg) [@system](https://forums.freertos.org/u/system)\ **Post date:** [November 2, 2012, 7:23am UTC](https://forums.freertos.org/t/pic32-application-using-queue-crashes/5131/3 "2012-11-02T07:23:43Z")
**[aethamyn](https://sourceforge.net/u/aethamyn/)** wrote on [Friday, November 02, 2012](https://sourceforge.net/p/freertos/discussion/382005/thread/dfef08af/#a04d): - Main(): ``` int main(void) { vSetupHardware(); Create_Ressources_OSTracing(); vTaskStartScheduler(); return 0; } ``` - Create\_Ressources\_OSTracing(): ``` ErrorCode_t Create_Ressources_OSTracing (void) { ErrorCode_t ErrorCode = {0}; #ifdef OS_TRACE // 1. Create Task if((ErrorCode.Code&ERRCODEMASK) == CODE_000_NO_ERROR) { if(xTaskCreate(_OS_Trace_TaskHandler, "RTOS Trace Task", STACKSIZE_OS_TRACE, NULL, PRIORITY_OS_TRACE, &TASK_OSTracing) != pdPASS) { ErrorCode.Code = LAYER_Service | TASKID_OSTrace | CODE_002_MEMORY_ALLOCATION_ERROR; } } // 2. Create Message to Send Queue if((ErrorCode.Code&ERRCODEMASK) == CODE_000_NO_ERROR) { Q_OSTracing = xQueueCreate(MAX_MSG_Q_OS_TRACE, sizeof(OS_TRACE_Msg_t)); if(Q_OSTracing == NULL) { ErrorCode.Code = LAYER_Service | TASKID_OSTrace | CODE_002_MEMORY_ALLOCATION_ERROR; } else { #if __DEBUG vQueueAddToRegistry(Q_OSTracing, "OS Tracing Queue"); #endif } } #endif return ErrorCode; } ``` - The task - \_OS\_Trace\_TaskHandler(): ``` void _OS_Trace_TaskHandler (void * pvTaskParam) { OS_TRACE_Msg_t TraceMsg; OS_TRACE_Time_t TraceTime; vTaskDelayMs(2000); while(1) { if(xQueueReceive(&Q_OSTracing, &TraceMsg, portMAX_DELAY) == pdPASS) { if(TraceMsg.DateFlag) { _OS_Trace_GetTime(&TraceTime); _OS_Trace_FormatTime(&TraceTime, &TraceMsg); } _OS_Trace_LogTrace(&TraceMsg); } } } ``` vTaskDelayMs() is a macro that calls vTaskDelay and converts parameter in ms to ticks with portTICK\_RATE\_MS. ---
**Author:** ![rtel](https://d3iykfbgfh8zhg.cloudfront.net/user_avatar/forums.freertos.org/rtel/32/31_2.png) [@rtel](https://forums.freertos.org/u/rtel)\ **Post date:** [November 2, 2012, 10:01am UTC](https://forums.freertos.org/t/pic32-application-using-queue-crashes/5131/4 "2012-11-02T10:01:12Z")
**[rtel](https://sourceforge.net/u/rtel/)** wrote on [Friday, November 02, 2012](https://sourceforge.net/p/freertos/discussion/382005/thread/dfef08af/#995b): I’m curious why you test ``` if((ErrorCode.Code&ERRCODEMASK) == CODE_000_NO_ERROR) ``` when ErrorCode is a local variable and just been initialised so can’t hold any value other than 0, but that is probably not relevant. What is probably relevant is the following call: ``` if(xQueueReceive(&Q_OSTracing, &TraceMsg, portMAX_DELAY) == pdPASS) ``` You don’t show the definition of Q\_OSTracing, but I suspect you don’t need the ‘&’ in front of it. If you declare it as: ``` xQueueHandle Q_OSTracing; ``` …and it the queue has been created, then you can read from it using: ``` xQueueReceive(Q_OSTracing, &TraceMsg, portMAX_DELAY); ``` As you are using portMAX\_DELAY, you only need to test the return value if INCLUDE\_vTaskSuspend is not set to 1 in FreeRTOSConfig.h.  That is because if INCLUDE\_vTaskSuspend is set to one portMAX\_DELAY will act as an indefinite wait. Regards. ---
**Author:** ![system](https://d2v6vdsk2p900z.cloudfront.net/original/1X/7fc8fdb729c645aab5b20282bbe34e57cb407be6.jpeg) [@system](https://forums.freertos.org/u/system)\ **Post date:** [November 2, 2012, 12:25pm UTC](https://forums.freertos.org/t/pic32-application-using-queue-crashes/5131/5 "2012-11-02T12:25:22Z")
**[aethamyn](https://sourceforge.net/u/aethamyn/)** wrote on [Friday, November 02, 2012](https://sourceforge.net/p/freertos/discussion/382005/thread/dfef08af/#255e): > when ErrorCode is a local variable and just been initialised so can’t hold any value other than 0, but that is probably not relevant. Yes it is, actually it’s more a “way” that I try to respect, I agree this test isn’t usefull 😉 > What is probably relevant is the following call:  You don’t show the definition of Q\_OSTracing, but I suspect you don’t need the ‘&’ in front of it. If you declare it as: > xQueueHandle Q\_OSTracing; Exact ! I’m more familiar with EmbOS from Segger, in which queue type is a structure, not a handle, which is actually just a void pointer … I made the same mistake when I wanted to put a message into the queue : ``` if(xQueueIsQueueFullFromISR(Q_OSTracing) != pdFALSE) { xQueueSend(&Q_OSTracing, &TraceMsg, MS_TO_TICK(50)); } ``` That’s why I got troubles in sending messages too. > As you are using portMAX\_DELAY, you only need to test the return value if INCLUDE\_vTaskSuspend is not set to 1 in FreeRTOSConfig.h. That is because if INCLUDE\_vTaskSuspend is set to one portMAX\_DELAY will act as an indefinite wait. Yes, my task is suspended. I will let the test because this task maybe be used with different configuration of FreeRTOS, it is some kind of generic method to trace OS and application events for a few different  FreeRTOS based softwares. Anyway, thank you for your help !