nRF Connect for desktop - Select serial port error

[ricsilvs]

When using nRF connect for desktop on ubuntu I can't go through the "Select serial port" step because I got the following error message: "Could not open the port. Please power cycle the device and try again."

In the log file I got this:

ERROR Could not open the port. Please power cycle the device and try again.

DEBUG Error: Could not open the port. Please power cycle the device and try again. at /opt/nrf-connect-linux-x64/resources/app/js/actions/adapterActions.js:305:24 at SerialPort._error (/opt/nrf-connect-linux-x64/resources/app/node_modules/serialport/lib/serialport.js:186:5) at SerialPort. (/opt/nrf-connect-linux-x64/resources/app/node_modules/serialport/lib/serialport.js:209:19)

[Sigurd]

You might need to grant serial port access permissions to your user. This can be done by typing the following command to the command line:

sudo usermod -a -G dialout <username>

Also make sure that you have SEGGER J-Link Software installed, and that you are using one of the supported devices (PCA10028, PCA10040 and PCA10031).

More information about nRF Connect is available here.

[Eric Smith]

I've confirmed that I'm a member of the dialout group, and that the device file has read and write permission for dialout, but the port still isn't showing up in nRF Connect 2.4.0.

$ id
uid=1000(eric) gid=1000(eric) groups=1000(eric),10(wheel),18(dialout) context=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023
$ ls -l /dev/ttyACM*
crw-rw----. 1 root dialout 166, 0 Jul 18 15:34 /dev/ttyACM0

Even if I change the device file permissions to 666, nRFConnect 2.4.0 doesn't list it.

If I run nRF Connect as superuser, which I really don't like to do, the device is found.

If I extract the contents of the nrfconnect AppImage and run the nrfconnect binary under "strace -f", that shows that as I try to use it, /dev/ttyACM0 is successfully opened several times. The strace output is of course quite voluminous, and I can't easily spot anything obviously wrong.

[Joakim Jakobsen]

Hi!

Sorry about the delay.

Did you make any progress regarding your issue?

Regards,
Joakim.

 

 

[Eric Smith]

No, I still can't get it to find the port. Other applications can find and open the port without difficulty. If I run Windows in a virtual machine and give it access to the port, nRFConnect on Windows can find and use it, but I'd really prefer to use it on Linux.

[Joakim Jakobsen]

Hi!

I've talked to our developers, and they were able to reproduce your issue.

Installing our udev rules for nRF development kits solved the issue.
https://github.com/NordicSemiconductor/nrf-udev

Let me know if that works for you.
Best regards,
Joakim.

[Eric Smith]

Thanks! I do have some udev rules for the device, but possibly they are wrong. I will try your udev rules from github and let you know. It's odd that manually setting the permissions on the /dev/ttyACM<n> device to 666 wouldn't be sufficient. (Without udev rules, I'd have to do that every time, but it should work for testing.)