My question is related to semaphores. I am playing with the ATMega323_WinAVR demo. I looked up the mutex semaphore in the API reference, copied the mutex example into the demo, and compiled it. Got an error complaining about an "undefined reference to xQueueCreateMutex". If I drop in a binary semaphore is compiles just fine.  I have queue.c compiled and queue.h included.  Again, I’m sure I’m just missing something simple.  Any ideas?

Did you define configUSE_MUTEXES in your FreeRTOSConfig.h ?

Good call.  That’s all it took.  But now my question is … how should I have known this?  The FreeRTOSConfig.h says "THESE PARAMETERS ARE DESCRIBED WITHIN THE ‘CONFIGURATION’ SECTION OF THE FreeRTOS API DOCUMENTATION AVAILABLE ON THE FreeRTOS.org WEB SITE."  But I can’t find a "Configuration" section.  What are they talking about?  

http://www.freertos.org/a00110.html

i have the same problem