Printer makes only garbage from CM3

I am having trouble getting any consistent or useful output from my DevTerm printer with a CM3 module and image installed. It prints only a short part and then either turns to random mojibake for a little, or just stops totally.

See this picture of many different attempts:

  • Firefox trying to print a very simple webpage ( it kind of gets the header but then just goes to random little wing-ding characters
  • Chrome is even worse, just a short little bit of random garbage nothing like the print preview shows
  • from LibreOffice Draw it kind of works but only for the first ~1mm or so and then it just stops
  • even printing plain text from notepad type app or piped into lp it does maybe one line but then overlaps and stops and just all messed up

This is with the CM3 image on SD Card + sudo apt update && sudo apt full-upgrade.

Funny, with the R-01 it actually Just Worked® really well, I could print from Qutebrowser and Inkscape and pretty much anything and I’d get a reasonable tiny printout! Very fun!

But with the CM3 it is not any fun, just short scraps of useless random mess no matter what I try to print or what app I print from. Is there something I can try to fix this?

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Does the test print get printed fine?

echo -en "\x12\x54" > /tmp/DEVTERM_PRINTER_IN This command will print the test page

Thanks, yes the test print works. Picture is of test print which is not perfect with some stripes and blotches but is basically fine overall (Fun logo, Temperature 0ºC, Firmware version 0.10, etc.)

Then in picture followed by other tests:

  • help cd | lp repeated many times (the half lines of text)
  • print of clipart file via lp ~/Downloads/clipart1574.png several times (the five dark blotches)
  • print of clipart from browser with headers/footers on (just the “clipart157… file:///hom…” line result, the space above/below is from manually tugging on paper not the feed setting it is supposed to have!)
  • print of clipart from browser with headers/footers off (the final short blotchy section pulled out manually)

You can see the random clipart PNG file I found on the DevTerm screen, basically what gets printed is sort of a correct start but then it always just stops after a millimeter or two. (Although sometimes in earlier tests as in my first post it would either switch to random dingbat characters or other mess sometimes too.)

Update: maybe from Printer Troubleshooting on R-01 - #4 by guu the printer driver does not automatically update? I can try more things tonight but as I said I did already sudo apt update && sudo apt upgrade and the update does fetch from the clockwork repository, just no new packages from them! And that post was re. different platform/architecture where it was working fine for me too; it’s the more common CM3 distro where it’s broken for me!)

No luck, it looks like I already have the latest releases for armhf/CM3:

pi@clockworkpi:~ $ apt show devterm-thermal-printer
Package: devterm-thermal-printer
Version: 0.35
Priority: optional
Section: utils
Maintainer: cuu <>
Installed-Size: 168 kB
Depends: socat, fonts-noto-cjk
Download-Size: 46.0 kB
APT-Manual-Installed: yes
APT-Sources: stable/main armhf Packages
Description: Thermal printer daemon for DevTerm

pi@clockworkpi:~ $ sudo apt install devterm-thermal-printer devterm-thermal-printer-cups
Reading package lists... Done
Building dependency tree
Reading state information... Done
devterm-thermal-printer is already the newest version (0.35).
devterm-thermal-printer-cups is already the newest version (0.1).
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.

But the armhf repository has a devterm-thermal-printer version (0.35) lower than in arm64 (0.37) and RiscV (0.39). Is this my problem, that Clockwork doesn’t update their distros? Or is there something else?

Did the printer just work out-of-box for everyone else on CM3 or is this a known issue?

Found one clue in /var/log/syslog, entries like:

Feb 7 18:11:15 raspberrypi systemd[1]: devterm-printer.service: Main process exited, code=killed, status=11/SEGV
Feb 7 18:11:15 raspberrypi systemd[1]: devterm-printer.service: Failed with result 'signal'.

But why does it SEGV for me? This is basically just stock brought up-to-date and a few unrelated packages (just random stuff like gnome-mahjongg and jstest-gtk) installed.

Did you install snapd and something else requiring snap? This was an issue before, and I wouldn’t be surprised if it never got fixed in the OS image. I’m not sure if it was a CM3 issue though, but maybe it affects all the platfiorms.

For cm3:

sudo apt update
sudo apt install -y devterm-thermal-printer
sudo reboot

just updated ,hope can fix this issue

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I was able to try this tonight, and the updated driver works great! Thanks for the quick fix. I can print from lp and from browser and everything works as expected. :partying_face:

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