[sudo-discuss] line printer at sudoroom!

[Jake]

I brought in a Panasonic KX-P2180 Dot Matrix printer a while ago, and 
someone found some tractor-feed paper for it.

I want to use it to print lines from IRC when someone says

12:34 < jerkey> !print 12:33 < sudobot> DOOR EVENT: RichardStallman swiped into the building

the printer will actually print that line onto the paper and advance one 
line like a typewriter.

this is what a dor-matrix printer looks like in action:
(ours will be printing lines of text, not graphics)
https://youtu.be/qlEUrEVqDbo?t=28

so i got a USB to parallel converter, and i plugged it into the desktop 
computer next to the 3D printer.  It comes up as /dev/usb/lp0 because of 
kernel module usblp, which sees the hardware and makes that device.

If i become root, i can do
echo "hello world" > /dev/usb/lp0
and it will print "hello world" to the paper, and advance to the next 
line.

this works a couple of times, but then the printer stops printing, and 
then the command doesn't exit, until you press a button on the printer and 
then it prints SOME of what you sent it, and you have to press the button 
again and again... it makes no fucking sense.

I experienced this in the past too, playing with the same kind of printer, 
probably under DOS, and I never figured out what the fuck was wrong.

any ideas?  the printer is still set up on the desk if you want to play 
with it.

-jake