Hello, My application uses the CPU STM32F437+ freeRTOS+ environment IAR I wish I were confirmed: - The CSTACK whose size is set in the file stm32f437xI.icf is used until it is launched function vTaskStartScheduler? So it is? Another question The interrupt functions use CSTACK or task stack? Carlo

Before the scheduler is started only the CSTACK exists, so that is the only stack used. After the scheduler has started the stacks used by the tasks come from the FreeRTOS heap, and the CSTACK is used by interrupts.

Regards.

Thanks for the answer clear and comprehensive