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Semaphore doesn't wait for blocktime

Posted by chaabanemalki on February 18, 2015


I have a semaphore that at some point returns pdFALSE (0) immediately without waiting for the defined blocked time.

This is how my code looks like

~~~~~~ while ( condition ) { // Send DATA1 if (xSemaphoreTake( GSMRdy2SndbSemphore, FTP_TO ) == pdPASS ) { // Treat response;


} ~~~~~~

FTPTO is TickTypet type. and is initialized before starting the scheduler .

First I send DATA1, so the semaphore wait "FTPTO" seconds before returning pdFALSE. The code will send again DATA1 and the semaphore at this point will return 0 immediately without waiting FTPTO ? I'm not sure what might be the issue here ?

I'm using PIC32MX port and FreeRTOS V8.0.0. Below is the trace log view of the weird behavior I described above

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Semaphore doesn't wait for blocktime

Posted by rtel on February 18, 2015

How is the trace log being generated? Are you using trace macros? If so, what is the behaviour if you remove the trace macros - the same or different? (by remove I mean don't define them so they get defined away to nothing an don't generate any code)


Semaphore doesn't wait for blocktime

Posted by chaabanemalki on February 19, 2015

I use FreeRTOS+Trace library to generate this trace log. I'll try to disable it and try to see what would happen.

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