RTOS is not working in STM32F072.

[AP.6]

I have created a project in STM32CubeIDE with UART and some GPIO's as Input and Output.

I have created 2 Tasks using FreeRTOS - CMSIS v1(osPriorityNormal, osPriorityBelowNormal) with different osDelay(osDelay(500);, osDelay(600);). 

I have compiled and Flased to STM32F072CBT6 board. Both threads are working fine(Using UART printing some debug messages and blinking LEDs), after sometime board hangs, and nothing has transmitted over UART and LED also Stops blinking.

[MM..1]

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