Unknown USB Device (Device Descriptor Request Failed)

[yoursunny]

I want to collect debug logs written by printf statements over USB-UART. However, after I upload any firmware to the USB mass storage device, the device reboots and my Windows 10 computer recognizes it as Unknown USB Device (Device Descriptor Request Failed).

I tried to plug the kit to a Linux computer (RPi 3B), but dmesg shows device descriptor read/64, error -32 and unable to enumerate USB device.

printf is a vital way to debug code without using a SWD debugger. Is there any driver (Windows or Linux-ARM) that I can use to enable USB-UART?

[theophileleroy]

after I upload any firmware to the USB mass storage device

Wich file are you trying to upload to Rapid-IOT? Just to be sure, it must be a .bin file generated after compiling your project. Located under /Debug folder.

[yoursunny]

Yes it is /Debug/*.bin. I know how to upload and I can upload an example and run it successfully. I just want to see printf without using Bluetooth.

[theophileleroy]

To be confirmed, for now, only SWD debug via docking station is available on Rapid-IoT. I am not aware of driver for uart over usb.

[stephanie_m]

Hello,

Just to confirm, you are working with the Rapid IOT studio and you are programming the kit with it and you are trying to debug it through USB? 

Have you tried a debug like the one they use here? 

https://community.nxp.com/thread/489735  

Regards, 

Estephania 

[yoursunny]

No, I'm programming in MCUXpresso. I want to write debug logs without relying on Bluetooth, because my project needs to use the Bluetooth to connect to an ESP32, not a phone or tablet.

[stephanie_m]

Hello, 

And after using the printf, you do not see anything in neither the debug console nor the console of  MCUXpresso, is that correct? Just to verify the state of the semi-hosting 

Also, by any chance, have you checked that example as well? 

Regards

[yoursunny]

There is no console. The computer doesn't even recognize the USB device.

Debug Print Demo is not a MCUXpresso project, so it cannot help me. I need a solution for MCUXpresso.