AnsweredAssumed Answered

STM32L4 USB Not Triggering Interrupt On Disconnect

Question asked by kenney.jacob on Oct 21, 2016
Using an STM32L4 processor, I am trying to detect a USB connect and disconnect within the interrupt handler, however I only trigger the interrupt when I plug in a USB and not when I disconnect it. I have VBUS (5V) brought down to 3.3V and running into ping PA9 which is set to handle VBUS and triggers the interrupt on connect.

What could be causing the interrupt to not trigger on disconnecting the USB? I have an Eval board with the same processor family and practically the same project loaded on and that one triggers on both connection and disconnection of the USB so I know how this should be working, it just doesn't seem to be. The only noticeable difference is that the EVAL board has the ID line connected, but I don't think it ever is actually used beings both projects are configured as device only.

Any help with getting the disconnect interrupt to be read would be greatly appreciated, thank you.

Outcomes