Activate RS232 for serial terminal

[mackowiakp]

In Mandriva /etc/inittab was active. So I can put in to the file line as shown below, to be able connect serial line terminal emulator like minicom.

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0:respawn:/sbin/agetty -L ttyS0 -H 19200 vt100

Can anybody what and where to have similar facility?

And next question - is any GUI for minicom? Or any other good serial line terminal emulator (VT100) with graphic interface?

[doktor5000]

You may want to look at http://0pointer.de/blog/projects/serial-console.html and http://linuxwave.blogspot.de/2009/06/hy ... linux.html

[mackowiakp]

According to Your links i try to enable login prompt at serial line, but system errors are reported. But the hardware seeams to be OK:

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[root@media Pobrane]# systemctl enable serial-getty@ttyS0.service
The unit files have no [Install] section. They are not meant to be enabled
using systemctl.
Possible reasons for having this kind of units are:
1) A unit may be statically enabled by being symlinked from another unit's
   .wants/ or .requires/ directory.
2) A unit's purpose may be to act as a helper for some other unit which has
   a requirement dependency on it.
3) A unit may be started when needed via activation (socket, path, timer,
   D-Bus, udev, scripted systemctl call, ...).
[root@media Pobrane]# setserial /dev/ttyS0
/dev/ttyS0, UART: 16550A, Port: 0x03f8, IRQ: 4
[root@media Pobrane]# ps -t /dev/ttyS0
  PID TTY          TIME CMD
[root@media Pobrane]# ls -la /dev/ttyS0
crw------- 1 media tty 4, 64 lip 19 17:42 /dev/ttyS0

[doktor5000]

And what does your serial-getty@ttyS0.service contain currently?

[mackowiakp]

Yep. Right, Theres no such service in /etc/systemd/system/*.
I linked:

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ln -s /lib/systemd/system/serial-getty@.service /etc/systemd/system/getty.target.wants/serial-getty@ttyS0.service

And in this moment I have:

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[root@media ~]# ps -t ttyS0
  PID TTY          TIME CMD
  652 ttyS0    00:00:00 agetty

Looks good

[mackowiakp]

The content of serial-getty\@ttyS0.service file is:

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[root@media getty.target.wants]# cat serial-getty\@ttyS0.service
#  This file is part of systemd.
#
#  systemd is free software; you can redistribute it and/or modify it
#  under the terms of the GNU Lesser General Public License as published by
#  the Free Software Foundation; either version 2.1 of the License, or
#  (at your option) any later version.

[Unit]
Description=Serial Getty on %I
Documentation=man:agetty(8) man:systemd-getty-generator(8)
BindsTo=dev-%i.device
After=dev-%i.device systemd-user-sessions.service plymouth-quit-wait.service
After=rc-local.service

# If additional gettys are spawned during boot then we should make
# sure that this is synchronized before getty.target, even though
# getty.target didn't actually pull it in.
Before=getty.target
IgnoreOnIsolate=yes

[Service]
ExecStart=-/sbin/agetty -s -8 %I 19200 vt102
#ExecStart=-/sbin/agetty -s %I 115200,38400,19200,9600 vt100
Type=idle
Restart=always
RestartSec=0
UtmpIdentifier=%I
TTYPath=/dev/%I
TTYReset=yes
TTYVHangup=yes
KillMode=process
IgnoreSIGPIPE=no

# Some login implementations ignore SIGTERM, so we send SIGHUP
# instead, to ensure that login terminates cleanly.
KillSignal=SIGHUP


And status shows:

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[root@media getty.target.wants]# systemctl status serial-getty@ttyS0.service
serial-getty@ttyS0.service - Serial Getty on ttyS0
          Loaded: loaded (/lib/systemd/system/serial-getty@.service; enabled)
          Active: active (running) since Fri, 2013-07-19 23:38:12 CEST; 6min ago
            Docs: man:agetty(8)
                  man:systemd-getty-generator(8)
        Main PID: 634 (agetty)
          CGroup: name=systemd:/system/serial-getty@.service/ttyS0
                  └ 634 /sbin/agetty -s -8 ttyS0 19200 vt102

My minicom is set to VT102 emulation, 19200 8N1

And minicon displays random characters. It I ryn agetty manually, minicom works OK.
Probably there is en error in serial-getty\@ttyS0.service file. Any idea?

[mackowiakp]

Finally it works. But
- only 9600 8N1 terminal communication settings works (minor problem)
- my national letters are not display properly, even in login prompt. For example word "passwaord" in translation to my language contains Polish letter

So that is serial port status:

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[root@media ~]# systemctl status serial-getty@ttyS0.service
serial-getty@ttyS0.service - Serial Getty on ttyS0
          Loaded: loaded (/lib/systemd/system/serial-getty@.service; enabled)
          Active: active (running) since Sat, 2013-07-20 11:47:40 CEST; 3s ago
            Docs: man:agetty(8)
                  man:systemd-getty-generator(8)
        Main PID: 3420 (agetty)
          CGroup: name=systemd:/system/serial-getty@.service/ttyS0
                  └ 3420 /sbin/agetty -s -8 -L ttyS0 115200 38400 9600 vt10.

After login from serial console. the LANG env looks correctly:

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[root@media ~]# echo $LANG
pl_PL.UTF-8

But Polish letter are no display properly. What is and error?