gadkins wrote on Thursday, May 28, 2009:
I have created a very simple shell of a programme that I need to generate four time based tasks and a couple of event ones. Having problem I have simplified it the following:
static void prvTask5ms( void *pvParameters )
{
// some work here for first time through then
portTickType lastTickTime;
int x = 0;
// set up counter to start
lastTickTime = xTaskGetTickCount();
for(;
{
//Delay from last time run not now
vTaskDelayUntil(&lastTickTime, (5 / portTICK_RATE_MS));
// do something
x++;
}
}
static void prvTask10ms( void *pvParameters )
{
// some work here for first time through then
portTickType lastTickTime;
int x = 0;
// set up counter to start
lastTickTime = xTaskGetTickCount();
for(;
{
//Delay from last time run not now
vTaskDelayUntil(&lastTickTime, (10 / portTICK_RATE_MS));
// do something
x++;
}
}
In execution task prvTask5ms runs first (having a high priority) as you would expect but does not stop running after calling the delay function. Looking at the MPLAB OS window it shows the task to be blocked but executing, following the debug trail also shown the task moving from the running to the blocked queue, just before returning it calls Task yield, this seems to do nothing? So returns straight back to the tasks after that it will never work as the counter are out of sequence.
I have build and run the demo SW and this seems to show the same problem