Receiving queue message but nobody sends

Kernel
1

willywortel wrote on Tuesday, March 24, 2009:

I`m on pic32.

Have created a queue succesfully for RS485 task. No other task / file has the queue send function to this queue.

When using this:

        while( xQueueReceive( xRS485Queue, &Rs485msg, 1000 ) != pdPASS );
        // block as long as UART interrupt is still busy

After some amount of time (less then a minute) it manages to break the while loop.
I don’t get it. Anyone any suggestions where i should look? i`m sure nobody sends data to this queue

It doesnt happen when i use portMAX_DELAY, but from my insights it than only takes longer since
portMAX_DELAY = oxFFFF = 65535mS = ~ about an hour (when using 1000hz for os tick counter).
So i think when i use portMAX_DELAY it only takes longer when the loop breaks.

2

willywortel wrote on Tuesday, March 24, 2009:

Gets even more strange.

when using this test code:

        unsigned portLONG data = 0;
        while( data == 0 )
        {
            data = xQueueReceive( xRS485Queue, &Rs485msg, 1000);
            if(data)
            {
                while(1);
            }   
        }

Then the code gets in the while(1) part. When checking the data variable with the REALICE debugger, the variable is 0.

Still, nobody sends data to the queue

3

davedoors wrote on Tuesday, March 24, 2009:

Which version of FreeRTOS are you using?

4

willywortel wrote on Tuesday, March 24, 2009:

v5.1.2

5

rtel wrote on Tuesday, March 24, 2009:

I could not offer any explanation for that behaviour, it is not something I have seen or had reported before.

The queue receive implementation in V5.2.0 is different.  Try using that - it would be interesting to see if it made any difference.  V5.2.0 is completely backward compatible with V5.1.2.

Regards.

6

willywortel wrote on Tuesday, March 24, 2009:

Very stupid fault. Someone else in my repro worked on the same code for the USB.

In his peace of code he was using a function that used this queue

Shame on me :blush:

Sorry for your time. Thanks for the reply’s!!