On Wednesday, 13 March 2019 17:15:20 GMT Ralph Corderoy wrote: > It's hard to say because the systemd units configured will be specific > to Debian, or even Raspbian, and I think the names of the serial ports, > e.g. ttyAMA0, have changed between models because they nicked the SoC's > real UART for talking to Bluetooth, or something, and substituted > bit-banging in its place that has flaky timing depending on CPU-speed > changes. There the rumours I've heard, anyway, I'm out of touch with Pi > stuff.
Hmmm. I'm testing this with a Pi 3, but the target systems are all Pi Zeros. > `disable' stops it starting on booting rather than stopping it now. > `mask' blocks it from starting either manually, or as a dependency of > something else that's starting. That's what I thought. > `systemctl | grep getty' will show the systemd units, etc., involved in > your system. And http://0pointer.de/blog/projects/serial-console.html > suggests your simplest bet would be to alter the kernel's parameters so > systemd doesn't want to start a getty. That gave me: pi@raspberrypi:~$ systemctl | grep getty serial-getty@ttyS0.service loaded active running Serial Getty on ttyS0 system-serial\x2dgetty.slice loaded active active system-serial\x2dgetty.slice getty.target loaded active active Login Prompts I tried disabling 'serial-getty@ttyS0.service' but that didn't seem to work; if I stop the service, it is definitely gone, but a reboot brings it back. even after a disable I'm not sure what getty.target is doing, but it doesn't appear to be a service anyway. So still wondering. -- Terry Coles -- Next meeting: BEC, Bournemouth, Tuesday, 2019-04-02 20:00 Check to whom you are replying Meetings, mailing list, IRC, ... http://dorset.lug.org.uk/ New thread, don't hijack: mailto:dorset@mailman.lug.org.uk
