CooCox CoOS User's Guide

Example usage:
#include "CCRTOS.h"
OS_EventID semaphore;;
void TaskN (void *pdata)
{
StatusType result;
...
/* Pend a semaphore, Time out: 20 */
result = CoPendSem (semaphore, 20);
if (result != E_OK)
{
if (result == E_INVALID_ID)
{
printf("Invalid event ID !\n");
}
else if (result == E_CALL)
{
printf("Error call in ISR !\n");
}
else if (result == E_TIMEOUT)
{
printf("Semaphore was not received within the specified timeout time !\n");
}
}
else
{
…
/* Process semaphore here */
…
}
...
}
Note:
1)This function runs a task sheduling while waiting and give the system
execution time to the highest priority task.
2)The number of the semaphore resources substract 1 after getting the
resources successfully.
3)The function cann’t be used in the interrupt service program.
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