RetroPrinter Support

Hi - is this a problem with the pdfs generated by the Retro-Printer? If so, then I need the matching raw file to investigate.

If the odd is fine on the Retro-Printer, then it is a problem with the printer driver and we cannot do anything about it - as the software just prints the pdf to the default printer.

To investigate an issue on the Retro-Printer I need your config files and raw files.

Send it by email as that is easier

Still waiting on the raw file sample etc for the graph and confirmation of even which emulation mode you use on the Retro-Printer.

If you are using HP emulation, then assuming the PDF on the Retro-printer has the same issue as the uploaded sample, the black block on the graph could indicate a problem with the program GhostPCL which does the HP PCL code to PDF conversion.

Generally this is because a command sequence is used incorrectly by the original equipment. The Retro-Printer software does allow you to swap over control code sequences to overcome this but it is identifying the exact sequence of control codes which can be time consuming and tricky.

If you are using EPSON emulation, then it could reflect an issue in the graphics routine for the ESC/P emulator - we cannot test every possible combination of graphics codes without the raw data.

If it does not appear on the PDF stored on the Retro-Printer, then the issue is in the printer driver within CUPS, so you would need to find a different printer driver for your end printer.

Hello Rich,

I have to make special arrangements to gain access to the dyno so unfortunately I have not been able to get back there yet.
We are using HP emulation with a HP Color LaserJet 3301.

RWAP wrote: Thu May 07, 2026 6:35 am If you are using HP emulation, then assuming the PDF on the Retro-printer has the same issue as the uploaded sample, the black block on the graph could indicate a problem with the program GhostPCL which does the HP PCL code to PDF conversion.

You are on to something here. Please see the attached PDF. As you can see, the black graph is in fact present in the PDF, however unlike the printed version of the graph, the PDF version has data corruption on the bottom line (or so it looks). Assuming this is a GhostPCL related problem, are there any steps I can take to resolve it?

Again, thank you for all the help!

P.S.
I will do my best to get you those .RAW files as soon as possible.

If you are getting corruption at the end of the graph, it suggests that something is going wrong with the signals - remember a graph for example bay take longer to produce than plain text out put or show issues with handshaking.

Try increasing printer_delay and / or changing the handshaking value to see if that helps
Rich

Rich,

After going back to look at the graphs, only one ended up printing with random characters at the end of it, the rest did not.

Try increasing printer_delay and / or changing the handshaking value to see if that helps

How do I go about doing that? I am not sure where those settings are.

Also, I would like to send you the RAW files I have, but realized I don't know your email.

If you read the manual, you will find the settings for
/root/config/handshaking
/root/config/printer_delay

The latest version of the manual (v4.14) appears at:
https://www.dropbox.com/scl/fi/4tegqsjd ... e84is&dl=0

Section 7 covers configuring the Retro-Printer module (page 27 onwards).

You need to use Bitvise SSH to connect to the Retro-Printer and then edit the settings from within a console window with the command

nano /root/config/printer_delay
Change the value
CTRL x to exit and save

reboot the system.

I have sent you a pm with my email address.

RogueTech wrote: Tue May 19, 2026 7:44 pm Rich,

After going back to look at the graphs, only one ended up printing with random characters at the end of it, the rest did not.

Try increasing printer_delay and / or changing the handshaking value to see if that helps

How do I go about doing that? I am not sure where those settings are.

Also, I would like to send you the RAW files I have, but realized I don't know your email.