This is the documentation for the latest (main) development branch of Zephyr. If you are looking for the documentation of previous releases, use the drop-down menu on the left and select the desired version.

CMSIS RTOS v2

Cortex-M Software Interface Standard (CMSIS) RTOS is a vendor-independent hardware abstraction layer for the ARM Cortex-M processor series and defines generic tool interfaces. Though it was originally defined for ARM Cortex-M microcontrollers alone, it could be easily extended to other microcontrollers making it generic. For more information on CMSIS RTOS v2, please refer to the CMSIS-RTOS2 Documentation.

Features not supported in Zephyr implementation

Kernel

osKernelGetState, osKernelSuspend, osKernelResume, osKernelInitialize and osKernelStart are not supported.

Mutex

osMutexPrioInherit is supported by default and is not configurable, you cannot select/unselect this attribute.

osMutexRecursive is also supported by default. If this attribute is not set, an error is thrown when the same thread tries to acquire it the second time.

osMutexRobust is not supported in Zephyr.

Return values not supported in the Zephyr implementation

osKernelUnlock, osKernelLock, osKernelRestoreLock

osError (Unspecified error) is not supported.

osSemaphoreDelete

osErrorResource (the semaphore specified by parameter semaphore_id is in an invalid semaphore state) is not supported.

osMutexDelete

osErrorResource (mutex specified by parameter mutex_id is in an invalid mutex state) is not supported.

osTimerDelete

osErrorResource (the timer specified by parameter timer_id is in an invalid timer state) is not supported.

osMessageQueueReset

osErrorResource (the message queue specified by parameter msgq_id is in an invalid message queue state) is not supported.

osMessageQueueDelete

osErrorResource (the message queue specified by parameter msgq_id is in an invalid message queue state) is not supported.

osMemoryPoolFree

osErrorResource (the memory pool specified by parameter mp_id is in an invalid memory pool state) is not supported.

osMemoryPoolDelete

osErrorResource (the memory pool specified by parameter mp_id is in an invalid memory pool state) is not supported.

osEventFlagsSet, osEventFlagsClear

osFlagsErrorUnknown (Unspecified error) and osFlagsErrorResource (Event flags object specified by parameter ef_id is not ready to be used) are not supported.

osEventFlagsDelete

osErrorParameter (the value of the parameter ef_id is incorrect) is not supported.

osThreadFlagsSet

osFlagsErrorUnknown (Unspecified error) and osFlagsErrorResource (Thread specified by parameter thread_id is not active to receive flags) are not supported.

osThreadFlagsClear

osFlagsErrorResource (Running thread is not active to receive flags) is not supported.

osDelayUntil

osParameter (the time cannot be handled) is not supported.