[CentOS] resetting a serial port

Thu Dec 14 15:25:39 UTC 2023
Simon Matter <simon.matter at invoca.ch>

Hi,

> I have Centos 7 arm32 running on a Cubieboard and I am logged in as root
> on its serial uart from another system.
>
> On that system I use
>
> screen /dev/ttyUSB0 115200
>
> Well it was working well for a couple days, but now only garbage comes
> across.  Something messed up the serial link.
>
> pulling the usb cable to the usb/serial adapter does not reset things.
>
> I can ssh into the server and see root logged into ttyS0
>
> How do I reset that serial port so that I can work on the system?

I don't know how you can handle the wedged connection. But, I think you
troubles may come from the settings used. 115200 baud can be too fast to
run for a long time without errors. Also, I don't know how the default
handshaking is configured but maybe you have to add such settings as well.
Maybe something like "screen /dev/ttyUSB0 19200,ixoff,ixon" would work?

Regards,
Simon