crDELAY

Collaboration diagram for crDELAY:

croutine. h

crDELAY( CoRoutineHandle_t xHandle, TickType_t xTicksToDelay );

Delay a co-routine for a fixed period of time.

crDELAY can only be called from the co-routine function itself - not from within a function called by the co-routine function. This is because co-routines do not maintain their own stack.

Parameters

xHandle	The handle of the co-routine to delay. This is the xHandle parameter of the co-routine function.
xTickToDelay	The number of ticks that the co-routine should delay for. The actual amount of time this equates to is defined by configTICK_RATE_HZ (set in FreeRTOSConfig.h). The constant portTICK_PERIOD_MS can be used to convert ticks to milliseconds.

Example usage:

// Co-routine to be created.
void vACoRoutine( 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.
// We are to delay for 200ms.
static const xTickType xDelayTime = 200 / portTICK_PERIOD_MS;
 
  // Must start every co-routine with a call to crSTART();
  crSTART( xHandle );
 
  for( ;; )
  {
     // Delay for 200ms.
     crDELAY( xHandle, xDelayTime );
 
     // Do something here.
  }
 
  // Must end every co-routine with a call to crEND();
  crEND();
}