Modify DTM app to use USB CDC

[yuting0501]

Hi Nordic Team,

I've modified the DTM app to use USB CDC, I used a serial terminal to manually send commands, e.g. set tx power command, it worked fine. But it didn't work when I use nRFGo studio, I got the error "an error has occurred in the serial connection". I tried to debug the DTM application, I found APP_USBD_CDC_ACM_USER_EVT_PORT_OPEN event was not even triggered before the error occurred.

Do you have any idea?

The nRF Connect only recognize JLINK USB, I can't find my USB CDC on the "Select device" menu

The following is the source code.

3108.dtm.zip

Best Regards,

Eugene

[ovrebekk]

Hi Eugene

Could you try the Direct Test Mode module in nRF Connect for Desktop?

Most likely nRFgo Studio is not setting the DTR signal correctly, which means that the CDC port won't be opened properly. This is discussed in more detail in this Devzone case.

Best regards
Torbjørn 

[yuting0501]

It works on Windows PC, still doesn't work on Mac OS.

[ovrebekk]

Hi Eugene

I reported this to the developer.

According to him it is probably some issue with the serial port name filtering, but he needed a bit more time to look into it. 

I will get back to you when he has more to share. 

Best regards
Torbjørn