Yeah, definitely something amiss with bits 2 and 3. When I looked at a few characters it happened that they all became 0 instead of 1 and it was just dropping bits, but apparently it's also reading a 1 instead of 0 in some cases.
The M100 printer port is not 100% Centronics-compatible and it's also partially shared with the keyboard, so there might be a timing issue; I'm guessing you don't have another computer with a parallel printer port that you could try? m On Sun, Mar 17, 2024 at 4:17 PM Will Senn <will.s...@gmail.com> wrote: > I tried every config setting... twice or more :). > > It's super consistent in that bits 2, and 3, counting from zero, from the > least significant bits, are having some kind of issue (they aren't always, > zero, or one, but they are always the bits that are wrong and they are > consistently wrong (of the 40 chars or so I tested): > > <0x7f> vs w > 01111111 > 01110111 > 00001000 (b3 1->0) > > \ vs T > 01011100 > 01010100 > 00001000 (b3 1->0) > > 4 vs < > 00110100 > 00111100 > 00001000 (b3 0->1) > > 5 vs = > 00110101 > 00111101 > 00001000 (b3 0->1) > 6 vs > > 00110110 > 00111110 > 00001000 (b3 0->1) > > 7 vs ? > 00110111 > 00111111 > 00001000 (b3 0->1) > > 8 vs < > 00111000 > 00111100 > 00000100 (b3 0->1) > > 9 vs = > 00111001 (b3 0->1) > 00111101 > 00000100 > > Weird, huh? Anybody seen anything like it? Can I troubleshoot it with a > multimeter? > > Will > > > > > On 3/17/24 2:13 PM, Will Senn wrote: > > Yep, it's consistent. It took me a while to make some progress on this. I > tried redoing the Centronics side of the cable, and here's my source vs > what the pi sees: > > 10 PRINT "Hello, world!" > 20 GOTO 10 > > 10 PRMN\ "Lmllo, orll!" > 20 OO\O 10 > > I'm not sure how to troubleshoot... > > I found this in the retroprinter handbook: > > Missing Characters or Repeated Characters: > This is generally because the equipment sending the printout is using > a specific timing mechanism and not necessarily adopting the correct > Centronics signal methods for acknowledgement of data. > We have added the following configuration options to help address > this: > /root/config/handshaking > This allows you to specify how the handshaking is handled between > the computer and the Retro-Printer. This can help overcome issues > with lost characters or repeated characters when the equipment > misses the busy / acknowledge signals. > The parameter takes a value between 0 and 4. > 0 = Busy On (for 5ms), Busy Off, Ack On (for signal time), Ack Off > 1 = Ack On (for signal time), Busy On, Ack Off, Busy Off > 2 = Busy On (for 5ms), Ack On (for signal time), Busy Off, Ack Off > 3 = Ack On (for signal time), Ack Off, Busy On (for 5ms), Busy Off > 4 = Busy On and Ack On (for signal time), Ack Off and Busy Off > Default is 0 > > Any idea how the M100 handshakes? > > Will > > > On 3/17/24 7:18 AM, Mike Stein wrote: > > Is it consistent, i.e. do you always get the same garbled output for a > given file? > > At a fast glance it looks like bits 2 and/or 3 are being dropped; have you > checked the computer to Pi cable and connectors? > > m > > On Sun, Mar 17, 2024 at 2:14 AM Will Senn <will.s...@gmail.com> wrote: > >> I am finally coming back around to this. I bought a retroprinter a year >> and half ago or so and shelved it out of frustration. Now, I know a lot >> more about this sorta stuff and so I pulled it out, updated the software to >> latest and tried to get it working. >> >> The PI prints a test page fine, but it won't print anything I send it >> from the M100. After hours of troubleshooting, it appears that whatever >> codes the pi is sending aren't DMP-15, EPSON ESC/P or Plain Text codes... >> When I do llist, I see the data coming across to the retroprinter and have >> set up a file to capture, but I can't find anything that will make sense of >> the data. >> >> Here's a sample: >> >> 10 PRMN\ "lmllo" >> 1= RMS\ORM =0>NORM=0\O1>RMALR,M-,Q,,M-,C,,M,0-,C,,M,1->CL,M-=0>NM\\M >> 20 M=0 >> 2= O=0>OOS]B<0 >> 30 OOS]B<= >> >> It looks like reasonably valid data and not complete gibberish, but who >> am I to judge. Is it one of: >> >> Epson ESC/P 9 Pin - didn't work, when I tried it >> Epson ESC/P 24/48 Pin >> HP Printer (PCL3 or PCL5) >> HP Plotter (HP-GL) >> IBM ProPrinter >> Plain Text - didn't work, when I tried it >> Postscript >> Printronix-P Series >> Printronix-S Series >> Seiko QT-2100P >> Siemens PT-88 >> Apple Image Writer II >> Seiko STP >> Star Micronics SP700 >> Tandy DMP-105 - didn't work, when I tried it >> >> Help and thank you. >> >> > >
