USBD on nRF52840 dongle

[Gerry]

Hi,

I modified your USBD BLE UART Example by commenting out the button and LED code to run on a dongle with J-Link debugger soldered on.

I removed the bootloader and set NRF_UICR->REGOUT0 to 3.3V, to ensure proper voltage.

The example runs, all USBD-functions return NRF_SUCCESS when starting up. Also the virtual comport is listed on the PC.

When sending data from a terminal, nothing happens. the cdc_acm_user_ev_handler is never fired.

Is there someting I'm missing?

Working with nRF5_SDK_15.2.0 and debugging with SES.

Best regards

Gerry

[Gerry]

Hi,

I changed this, thanks for the input. The behavior is still the same. I now tried with the original (unchanged) example on a nRF52840 DK and I have the exact same issue. When I send some characters to the virtual comport the terminal program gets stuck. Could this be a driver issue? I also tried another USB-port and uninstalled the driver. When I plug in USB, the driver is installed autom. and shows no errors. 

I'm using Windows10 and this terminal program

[Einar Thorsrud]

Hi,

It is expected that you get the same behavior using a DK and a dongle.

Gerry said:

When I send some characters to the virtual comport the terminal program gets stuck. Could this be a driver issue?

I am not sure. Is there a pattern? Always the same number of characters? Or something else?

Gerry said:

I'm using Windows10 and this terminal program

It should not matter, but could you test with PuTTY? 

[Gerry]

Hi,

PuTTY was a good idea. Everything works fine with PuTTY even on the dongle. Sadly, this seems to be the only terminal it's working with. I also have an own PC-application written in c# that works fine with my application on the nRF52840 DK, but not with the USBD BLE UART example.

In the end, I will have to communicate from/to that custom PC-application to the dongle.

Do you have an idea, what could cause this problem? There must be a difference in this virtual com ports right?

[Gerry]

Hi,

I finally found the cause of that problem. DTR of the terminal has to be set, see this post

Thanks for your support anyway.