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Posted by dnadler on August 25, 2016

Hi Richard ! I got an assertion when I forgot to set an interrupt's priority (thanks for that!). I set it to configMAXSYSCALLINTERRUPT_PRIORITY and the code no longer asserts. However, the comments in FreeRTOS and documentation are approximately as follows:

~~~ // ISRs using FreeRTOS APIs (for example, USB CDC driver uses FreeRTOS queues) must have priority // logically lower (numerically higher) than configMAXSYSCALLINTERRUPTPRIORITY. // For an interrupt priority to be lower than configMAXSYSCALLINTERRUPTPRIORITY, // it must be numerically higher than configMAXSYSCALLINTERRUPT_PRIORITY, because on the // ARM Cortex-M3 numerically low priority values represent logically high interrupt priorities. ~~~

Should the comments/documentation read "less than or equal to"? Or should the code be asserting if I do the following? NVICSetPriority (USBIRQn, configMAXSYSCALLINTERRUPT_PRIORITY);

Thanks as always, Best Regards, Dave


Posted by rtel on August 25, 2016

You are right, it should say less that or equal to.


Posted by dnadler on August 28, 2016

Thanks Richard!

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