nRF52 Tx Signal Present, Not seen out of virtual COM Port

[tcbriese]

Update to below: I get data out of the VCP and into Termite for a sub-second when I first power the board (with handshaking enabled), then I get no subsequent data (even though I see it on the TX pin). Does the VCP receive get taken over by some other driver? What am I missing here?

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I have a nRF52832 eval board that I am bringing up. Trying to get the COM port working so that I can use it for some debugging during SW development.

Anyways, I have the code for the ble_app_uart running as described here:

devzone.nordicsemi.com/.../

My issue is this. I can send data from Termite and see it on the Android app just fine, but I don't get the "Start..." text or any other text sent from the Android app to the PC. I can see the TX pin (P0.6) out of the nRF52832 toggling when I try to send data from the Android app, but it never seems to come out of the Virtual COM port. I have tried toggling the DTR signal in Termite, but still no luck.

I can also see the TX signal toggling when I step over the print for the "Start..." text. I've seen the same behavior with Tera Term as well.

[ovrebekk]

Hi

Most likely this is an issue with the configuration of Termite. Make sure you have done the following:

1. Enable RTS/CTS flow control
2. Turn on the "Status LEDs" feature
3. Click on RTS and DTR in the main gui so that they light up

Best regards
Torbjørn

[tcbriese]

This doesn't fix it. It seems more like a problem with the ATSAM part to me. I am going to look for a low level COM port sniffer in Windows to see if anything is still coming through. I do get 1 to 4 characters through when the board is first powered on and Termite is "waiting to connect" (so a string varying in length from "S" to "Star"....see image I added above). I can also send data from Termite to the nRF part and then see it on my phone.

[ovrebekk]

Could you try a different terminal program? Personally I use Tera Term most of the time, and I have not had any issues with it when running the ble_app_uart example.

[tcbriese]

I have tried it also. Are you running the ble_app_uart on the nRF52 device or some other board?

[Martijn]

We had a similar problem with the nrf51 dk.. We needed to enable dtr to be able to receive data in our terminal application.. We couldn't receive any data in our case though..

[tcbriese]

Yeah, I'm not getting anywhere with the DTR signal. Not sure if the code running on the interface IC (ATSAM) is not detecting this correctly or what. I got RTT working for input/output, but it kind of stinks that the UART app doesn't just work out of the box on this kit.