API Usage
[API]

Selecting the API to Use

• Only those API functions specifically designated for use from within an ISR should be used from within an ISR.

• Tasks and co-routines use different API functions to access queues. A queue cannot be used to communicate between a task and a co-routine or visa versa.

• Intertask communication can be achieved using the full featured API functions, the alternative API functions, and the light weight API functions (those with "FromISR" in their name).

• Use of the light weight functions outside of an ISR requires special consideration, as described under the heading "Performance tips and tricks - using the light weight API".

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Task API

A task may call any API function listed in the menu frame on the left other than those under the co-routine specific section.

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Co-Routine API

In addition to the API functions listed under the co-routine specific section, a co-routine may use the following API calls.

• taskYIELD() - will yield the task in which the co-routines are running.

• taskENTER_CRITICAL().

• taskEXIT_CRITICAL().

• vTaskStartScheduler() - this is still used to start the scheduler even if the application only includes co-routines and no tasks.

• vTaskSuspendAll() - can still be used to lock the scheduler.

• xTaskResumeAll()

• xTaskGetTickCount()

• uxTaskGetNumberOfTasks()

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