Linux, UART over USB frequently fails to connect

RE: Linux, UART over USB frequently fails to connect

Ladasky — Fri, 28 Jul 2017 22:35:18 GMT

Thanks for your reply, Martin. I will report back when I have tried your suggestions.

RE: Linux, UART over USB frequently fails to connect

MartinBL — Fri, 28 Jul 2017 07:06:34 GMT

To down grade you will need to replace the firmware with Segger Configurator like shown below:

If still you have later driver versions installed you might get that annoying message asking you to upgrade all the time, but it is worth a shot to see if it solves your problems.

It is Segger that is responsible for the drivers, not us, so it might also be a good idea to post your question on their forum too.

RE: Linux, UART over USB frequently fails to connect

Ladasky — Wed, 26 Jul 2017 20:04:56 GMT

Hi Martin,

Yes, I have tried several USB cables with the same result. For my final, minimal experiment, I appear to have reduced the problem to Windows vs. Linux as you can see.

I have thought of trying to get back older versions of the JLink drivers, and/or the firmware that JLink installs. This is an area of embedded systems programming that I do not understand as well as I would like. I am currently using JLink V6.16g on both Linux and Windows though. They match.

If I obtain an older version of JLink from SEGGER, will it downgrade the firmware file "J-Link OB-SAM3U128-V2-NordicSemi" that I sometimes see JLink updating on my boards? Or is that a separate issue? Might the firmware be responsible for my problems? What company is responsible for the firmware file?

If you have any suggestions about what to do, I would appreciate it. Thanks.

RE: Linux, UART over USB frequently fails to connect

MartinBL — Wed, 26 Jul 2017 13:20:53 GMT

Hi, Is there anyway for you to try and revert the J-Link drivers back to a pre-march version? And have you tried different USB cables? A few days ago there was a guy struggling with some USB issues, but I have no reason to suspect that your case is related to his though, other than that a few keywords seems to appear in both cases.