croutine.h
BaseType_t xCoRoutineCreate
(
crCOROUTINE_CODE pxCoRoutineCode,
UBaseType_t uxPriority,
UBaseType_t uxIndex
);
Create a new co-routine and add it to the list of co-routines that are ready to run.
- Parameters:
-
pxCoRoutineCode | Pointer to the co-routine function. Co-routine functions require special syntax - see the co-routine section of the web documentation for more information. |
uxPriority | The priority with respect to other co-routines at which the co-routine will run.. |
uxIndex | Used to distinguish between different co-routines that execute the same function. See the example below and the co-routine section of the web documentation for further information. |
- Returns:
- pdPASS if the co-routine was successfully created and added to a ready list, otherwise an error code defined with ProjDefs.h.
Example usage:
// Co-routine to be created.
void vFlashCoRoutine( CoRoutineHandle_t xHandle, UBaseType_t uxIndex )
{
// Variables in co-routines must be declared static if they must
// maintain value across a blocking call. This may not be necessary
// for const variables.
static const char cLedToFlash[ 2 ] = { 5, 6 };
static const TickType_t uxFlashRates[ 2 ] = { 200, 400 };
// Must start every co-routine with a call to crSTART();
crSTART( xHandle );
for( ;; )
{
// This co-routine just delays for a fixed period, then toggles
// an LED. Two co-routines are created using this function, so
// the uxIndex parameter is used to tell the co-routine which
// LED to flash and how long to delay. This assumes xQueue has
// already been created.
vParTestToggleLED( cLedToFlash[ uxIndex ] );
crDELAY( xHandle, uxFlashRates[ uxIndex ] );
}
// Must end every co-routine with a call to crEND();
crEND();
}
// Function that creates two co-routines.
void vOtherFunction( void )
{
unsigned char ucParameterToPass;
TaskHandle_t xHandle;
// Create two co-routines at priority 0. The first is given index 0
// so (from the code above) toggles LED 5 every 200 ticks. The second
// is given index 1 so toggles LED 6 every 400 ticks.
for( uxIndex = 0; uxIndex < 2; uxIndex++ )
{
xCoRoutineCreate( vFlashCoRoutine, 0, uxIndex );
}
}
CoRoutineHandle_t
Type by which co-routines are referenced. The co-routine handle is automatically passed into each co-routine function.
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