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

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

Thanks Richard!