Unable to wake task from event flag in ISR when USB_FS is enabled using CMSIS OS 2 on STM32L5

[MSher.1]

I have been using USB_FS for some time now and recently added the EXT13 IRQ for the user button in the STM32L5 DK. I set a task to toggle a pin when the button is pressed and noticed that if the USB is running, the event does not wake the user button task. If the USB is disabled or does not start properly, the task wakes and functions as expected. If I remove the event flag wait, the task functions normally. I have tried both IRQ priorities equal and lowering the USB priority with the same result that the task does not wake when the USB is active.

[Walid ZRELLI]

Hello @MSher.1​ ,

Can you please provide your project for further check?

Thanks in advance.

BeST Regards,

Walid

[MSher.1 · Accepted solution]

Hi Walid,
Thanks for the reply. Unfortunately, I’ve already moved on with a different approach using osThreadFlagsSet/Wait and don’t have the time to recreate the previous iteration. In the future, I will save the code in the troubled state for reference.
Best regards,
Michael

[Walid ZRELLI]

Hello @MSher.1​ ,

Thanks for your feedback 😊

BeST Regards,

Walid