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Scheduler gets stuck if more than 3 tasks

Posted by petermaier on April 26, 2016

Hi all, I am having trouble starting more than 3 tasks even if they're absolute dummy tasks.

I've built a project with STM32CubeMX which included freeRTOS as middleware.

IDE: Atollic TrueSTUDIO with GCC MCU: STM32151LCBU6

main.c: xTaskCreate(DataHandlerTask,"Data Handler", 280U, NULL, 4U, NULL); xTaskCreate(LightMeasureTask,"Light Measurement", 100U, NULL, 4U, NULL); xTaskCreate(TemperatureMeasureTask,"Temp Measurement", 100U, NULL, 4U, NULL); xTaskCreate(HumidityMeasureTask,"Humid Measurement", 100U, NULL, 4U, NULL); xTaskCreate(PressureMeasureTask,"Pressure Measurement", 100U, NULL, 4U, NULL); vTaskStartScheduler();

tasks (there are 5 identically simple tasks): void HumidityMeasureTask(void pvargs){ int32t humidityValue=0; for (;;) { osDelay(HUMIDITYTASKDELAYMS); } }

xTaskCreate returns in every case 1. After it gets stuck in vTaskStartScheduler() and does nothing.

If I create only 3 tasks everything works fine. However, if there are more than 3 tasks the scheduler is getting stuck. Is there a define for maximum tasks or something?

Any suggestions on how to get this working would be greatly appreciated. Peter Maier

Scheduler gets stuck if more than 3 tasks

Posted by rtel on April 26, 2016

Please read the heap management page on the FreeRTOS web site - could it be you just need to increase configTOTALHEAPSIZE?

Do you have a malloc failed hook defined?

Do you have configASSERT() defined?

Scheduler gets stuck if more than 3 tasks

Posted by petermaier on April 27, 2016

To increase configTOTALHEAPSIZE worked fine.

You made my day, thank you

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