AnsweredAssumed Answered

USB HID stop working

Question asked by ambroise2 on Jul 1, 2015
Latest reply on Jul 3, 2015 by ambroise2

We are working on USB HID with 64bytes IN and OUT reports with a stm32f401. We're using the stm32cude v1.6.0 for generated code, and we developped on KEIL v5.

The USB peripheral working well, we can speak with it from windows, sending/receiving packets. At a moment, the USB stack on the stm32 stop responding to the computer (we saw it on a logic analyzer, we never had ACK of the USB protocol). The stm32 continue working (leds still blinking, watchdog doesn't reset the board, debugger observation) but without the USB.

The only way we founded to get the USB communication back is unpluging/pluging the USB cable (the stm32 have an external power supply, so unplug/plug the cable doesn't perform a reset). But this solution is not acceptable for our final product.

(We made an eye diagram....etc... of the USB communication the problem isn't on the physical part).

Do you have any idea of what could make this communication failure ?

Thanks for your help !