Dear all, I have a situation which I am trying to undertand. The scenario is something like below. I have two tasks task_A and task_B A binary semaphore ABC is created. task_A( ) {       A();       delay 100ticks } task_B( ) {       B();       delay 100ticks } A( ) { if(xSemaphoreTake( ABC, portMAX_DELAY ) == pdTRUE )    {        // do something        xSemaphoreGive( ABC );        taskdelay (25 ms; //Note delay here    }    else    {           printf("Task A Error");    } } B( ) { if(xSemaphoreTake( ABC, portMAX_DELAY ) == pdTRUE )    {        // do something        xSemaphoreGive( ABC );  //Note NO delay here }    else    {           printf("Task B Error");    } } My setup is configured as 32bits, thereofre portMAX_DELAY will be large. However I see that I get errors "Task B Error".(and Task A error sometimes) Is it possible that the sempahore is timing out even with portMAX_DELAY or am I doing sonmething wrong here? Any insight will be appreciated. At he moment my workaround is while ((xSemaphoreTake( ABC, portMAX_DELAY ) != pdTRUE ), but I wnat to know what is wrong. -regards Narayan

Its difficult to say, as you are using a rather old version (there have been 23 updates since V3.2.2!).  There were some situation where a premature unblock was possible, and under certain circumstances the outer == TRUE was required, but I think this was to do with multiple tasks and interrupts accessing the same queue/semaphore.  Do you have anything else accessing the semaphore, or just these tasks? Can you update to a newer version? Regards.