Hands-On RTOS with Microcontrollers

Delay functions

Delay functions map cleanly between the two APIs:

CMSIS-RTOS name	FreeRTOS functions called	Notes
osDelay	vTaskDelay	osDelay is in ms or ticks, depending on which documentation and comments you believe. Be sure to check your CMSIS-RTOS implementation of osDelay() if a Systick frequency of something other than 1 kHz is used!
osDelayUntil	vTaskDelayUntil, xTaskGetTickCount

 

These basic delay functions work in very similar ways – the biggest difference to keep in mind is that CMSIS-RTOS specifies osDelay in milliseconds instead of ticks, as FreeRTOS does.