CDC ACM usb problem.

[Epasta]

Hello all,

I have 2 problem that I can not understand why.

1) Now cdc_acm isn't working anymore, but until 2 days ago it was working perfectly. I didn't change nothing. When I plug the USB cable to NRF52833DK in the NRF teminal I have the following message "usb_cdc_acm: Device Suspended" -> "usb_cdc_acm: Device Resumed" -> "usb_cdc_acm: Device Suspended", and Windows show me alert "Unknown device, descriptor request failed, error code 43. I have already tried with different USB cable, in different USB port, on second PC, in second DK (52840) and I have always the same result.

2) The second problem is the following:
I have second project on cdc_acm and when all worked goods, my purpose it was to pass "NRF USB" serial data to "UART_0" and viceversa (pass"UART_0" serial data to "NRF USB").
Everything it was good if I serial data gone from UART_0 to NRF USB. If the direction was the opposit (NRF USB to UART_0) i can see only the 32 byte and i can not understand why. I tried to change ring buffer size but without any result. My targhet is pass 128 byte in both direction.

Thanks to anyone that can help me
Best regards

[Epasta]

Hello,

i changed pc where I develop and it is fixed.
I can not undestand why my old pc is still unavailable, but does not matter i have new one pc and it is working.

Best regards

[Håkon Alseth]

Hi,

 

I'm glad to hear that the issue was worked around.

If you change the usb descriptor while developing, these issues will occur. You can try to delete the usb enumeration history on your old PC (search on google for "windows delete usb device history" or similar to find a guide)

 

Kind regards,

Håkon