vTaskStartScheduler() causes an Assertion

flat213 wrote on Wednesday, October 26, 2016:


i’m new to FreeRTOS and just want to set up a test project with Windows Port.
So i’ve started the demo project therefor and it works fine.

For my project i didn’t changed anything in the demo except of starting with the function main_blinky(), i start with the function usrAppInit(), which looks like that:

void usrAppInit(void)


void StartTasks(void)
	TaskHandle_t xNvmTaskHandle = NULL;
	TaskHandle_t xMainTaskHandle = NULL;
	xTaskCreate(NVMTask, "tNVMTask",initNVM_STACK_SIZE, ( void * ) 1, initNVM_TASK_PRIORITY, &xNvmTaskHandle );
	xTaskCreate(MainTask, "tMainTask", initMAIN_STACK_SIZE, (void *) 1, initMAIN_TASK_PRIORITY, &xMainTaskHandle );


	for (;; );

and both Tasks are empty(just a printf):

void MainTask( void * pvParameters )
	/* Prevent the compiler warning about the unused parameter. */
	( void ) pvParameters;

	for ( ;; )
		printf("Task Main ist dran\n");

When i debug this, i always get the following:

“ASSERT! Line 422, file c:…\timers.c, GetLastError() 0
Trace output saved to Trace.dump”

I know that the Assertion is caused by vTaskStartScheduling, but why? What can be wrong? I think it’s quite the same as in the demo which is running within the same project.

Thank you for helping!

flat213 wrote on Wednesday, October 26, 2016:

Ok, i have found the fail. Its because of my implementation to get my application started. It looks like this:



I don’t know which Line of Code exact causes the fail, but if i put my function instead of the blinky and start with mainCREATE_SIMPLE_BLINKY_DEMO_ONLY declared as 1, it should be ok.

You can delete or close.

tlafleur wrote on Wednesday, October 26, 2016:

Printf are not in general terms, “rtos friendly”. You might try running without them and see if you have the same issue.

Their is a friendly version in some of the demo code

flat213 wrote on Wednesday, October 26, 2016:

Yes, i read this. But i think for test purposes it’s ok to use printf. In my final project shouldn’t be any printf.
This didn’t cause the error.