Retro-Printer

18/05/2026

Went and helped out an optometrist in Walsall on Saturday.
They wanted to easily access scan results from their Zeiss Humfrey 720i Visual Field Analyser.

I added a retro-printer to the existing parallel printer port, and set it up as a network device on each of their PCs so that they could easily get the PDF files and add them to client records.

I even moved one PC off a wall onto a desk for them, whilst they were busy helping a customer and I was waiting to give them final instructions and say goodbye.

At long last they no longer need to print out the report on an aging Brother printer, and then scan it in (particularly grateful as the scanner could sometimes miss lines!)

One happy customer

The Retro-Printer provides low cost printer port capture hardware to capture data and connect computers & industrial equipment to modern printers.

11/05/2026

OK, so an old tractor feed printer has a certain buzz about it, but the amount of times you get a paper jam, or the holes don't quite line up properly can be a nightmare.

When we first dreamt up a modern replacement for the older printers used by vintage computers (in 1999) we never thought it would attract some of the biggest names out there.

We are actually getting an increasing number of enquiries now from industry who need to be able to replace their old dot-matrix printers with something that does not eat through paper and can be used to modernise their reporting processes.

That is where the Retro-Printer comes in - it acts as a printer emulator, capturing data from various sources and processing it to generate a PDF, or plain text reporting to a small screen, or SQL database for example.

We have even worked with industry to capture it from RS232, RS485, RS422, current-loop as well as the original parallel port.

Believe it or not, we recently sold a few modules to a large printer company as they couldn't print off reports from their own manufacturing line!

Everything is written in C which seems to be great for this type of project and our customers like the fact that they can approach us and know that we are happy to work with them to meet their specific process requirements.

The home computer market seems to be the harder nut to crack - probably because for most people, they don't really need a printer and so are happy to either do without, or just have the old printer for display purposes.

We were wondering whether there are any other types of market that we should be aiming at - or maybe if there are some much needed printer emulations, which we are missing!

More details

The Retro-Printer provides low cost printer port capture hardware to capture data and connect computers & industrial equipment to modern printers.

23/04/2026

Vintage computer festival GB due to be held at Aintree racecourse 11th -13th September 2026. Let's hope it is at least as successful as the Bletchley event.

We are planning to be there with a stall look for RWAP SOFTWARE

If you want to purchase a Retro-Printer module at the festival, please let us know beforehand.

17/04/2026

We are pleased to announce the release of the v3.36 Retro-Printer software. This release includes:

- Some minor improvements to the speed of reading the incoming data
- Tested successfully on Raspberry Pi 5
- Some improvements for where convert_PC850 is set alongside Strip-ESCP2-codes and improvements to the convert_PC850 to handle some more common characters
- Added a check for EOF in the serial data stream as this can latch on (tested with serial port aggregator for more than one input device).
- Improved handling of /root/config/end_of_job where several possible endings
- Added ability to open a file instead of a serial port for serial data (allows a FIFO accumulator to pull feed from several serial devices).
- Changes to ESC . 1 graphics commands (Epson emulation) to support non-standard parameters, as passed in Windows 3.11 driver
- Improvements to IBM emulation - ESC [ g command in particular did not work correctly.
- Improvements to CSV generation where parsing captured data to create the filename

12/01/2026

v3.35 Release

- Speed improvements which should hopefully be noticeable!
- Added timeout of -2 (provides unlimited timeout until an end of job text is found). use_eoj must be Yes
- Further improvements to End of Job string matching
- Added /root/config/offline_switch setting of USB - this enables the offline switch to take the unit offline and force an unmount of the USB memory stick if it is being used. When the unit is put back on line, the memory stick is mounted again.
- All streaming options (plain-stream, strip-escp2-stream, plain-jobs and strip-escp2-jobs) default to no printing and do not create PDF. These can be overwritten by the settings of /root/config/output_printer and /root/config/output_PDF
- Added the ability to use Form Feed to detect end of print job to all emulators
- Improvements to speed for the create_PDF function
- Added /root/config/background_emulator - set to YES if you want to allow the conversion routine to run in the background - it may impact the timing of the capture routine, dependent on how quickly your equipment is sending data to the printer.
- Prevented the capture being stuck in a loop in some circumstances

v3.34
- Removed fix in v3.33 re end of graphics being followed by a line feed. Found the issue was within GhostPCL - awaiting fix
- More custom changes for specific customers
- Corrected error with toggling between Centronics and Serial capture
- Corrected Exchange_strings code - we lost the last character if it was not a line feed
- Added check for Carriage Return at start of code - example where mixed in with form feeds before PCL data causing a blank page to be printed at start
- Added code to remove a Postscript Macro of 1234 checkvm macro (used to ascertain amount of memory available - which did not work under Linux)
- Fixed some minor issues with merge_pages
- Improved writing to CSV files.
- Corrected issue where data could be lost if new file printed whilst Retro-Printer is processing existing data
- Improved capture routine to improve speed of capture of the Centronics data.

08/05/2025

v3.32 Release of the Software (plus missed updates from v3.29 - v3.31)

- Change to the bold calculation which could look bad in some cases
- Change to the way underlined spaces are printed - to overcome alignment issues.
- Added /root/config/serial_interface to allow you to change the serial port from /dev/ttyUSB0
Other changes:
- Minor change to calculate of page number in case of a large number of raw files
- Update to handling of HP PJL sequence as one item of equipment sent a reset printer command to exit.
- Updated /etc/init.d/retroprinter to allow service retroprinter restart
- Improvements to strip-escp2-stream and plain-stream to enable better recovery if the Retro-Printer reboots
- Creating a 64 bit version - slightly quicker (Pi 3B or later only)
- Update GhostPDL to v10.05.0 (64 Bit version only)
- Improve communication between convert-pcl and printpcl.sh as PDFs might be missed when being stored on a USB memory stick.
- Printpcl.sh now converts the files in the ram disk if enabled
- Changes to handling of continuous_paper in convert-txt
- Changes to the output to HTTPS over CURL at end of print job.
- Change to how ESC J xx calculates the vertical movement in convert-escp2
- Initial code for handling UDG characters
- Started work on an ESC/POS emulator
- Added DSR/DTR control for the Serial port version
- Further code optimisation on the conversion routine libraries
- Corrections to the Job_Control setting for the offline_switch
- Changes to the convert-IBM routine - we found the OKI ML280 IBM conversion used different calculations for line spacing and graphics were at 144dpi not 120dpi for one customer.

There is now a 64 Bit version and a 32 Bit version of the software - there is a minor speed increase in the 64 Bit version (works on Pi 3B and later) and it allowed us to compile the latest version of GhostPDL used for the HP emulator.

11/03/2025

We have been adding more details of the industry types who are currently using the Retro-Printer:
https://www.retroprinter.com/about-the-retro-printer/supported-industry-types/

If you know of any others using this we would love to add details - or if you have any industry which might benefit from replacing an old printer with a modern alternative (or even electronic printouts), then why not get in touch and give it a go?

Here we explore just a few of the industries which we have helped with the Retro-Printer. Although we are only a small business based in the UK, we have been

07/02/2025

v3.28 Release of the Retro-Printer Software

This encompasses various updates to help the software run on later Raspberry Pi models, such as updating the WiringPi version to v3.12 (untested on Pi 5).

As well the normal minor bug fixes as we come across more edge cases (eg. to address an issue with the setting of the right margin), we have been working with industry on adding functionality to allow the printed data to be parsed into a CSV line or broadcast as a plain line of text to an email address, or SCADA system.

One interesting customer here has been a 9/11 emergency services customer in the US who send the jobs to its stations, where they are printed off for action - the older style modems being used by the system only support a serial printer over a null modem cable.

Their IT department are still trying to persuade the management that the Retro-Printer should email the job at the same time as printing it out.

05/12/2024

v3.26 Release

This has various changes to fix some bugs and improve conversion and is worthwhile changing to this version.

- Updated to latest Debian Raspberry Pi Operating System (Bookworm)
- Fixed bug in calculation of ESC C NULL X command (set page length to X inches)
- Retained GhostPCL v10.00.00 (v10.04.00 has issues on the Raspberry Pi).
- Improved speed of Printpcl.sh
- Added ability to convert printronix files by uploading raw files to /home/pi/data/pdf
- Fixed a bug in the merge_pdf routine
- Updated Libharu (used to create the PDF for non HP emulations to v2.4.4) - seems to improve speed
- Added /root/config/colour_mix to specify the colour mixing algorithm used to create the PNG (CMYK, RGB, MONOCHROME, GREYSCALE) - Monochrome and Greyscale are new
- Corrected an issue with the generation of a PNG as a file (output_PNG = file)
- Added /root/config/ouptut_printer = PCL to print the raw PCL / Postscript files direct to a USB printer (similar to JOB-PASSTHROUGH)
- Updated WiringPi v3.10.0 and config.txt for use on Raspberry Pi 5.
- Change to calculation of end of line for edge cases where text may wrap onto the next line
- Change to ESC I command to correct issue with some control codes which cannot be printed
- Change to handling of /root/config/serial settings as they could be ignored in some circumstances

21/11/2024

The past couple of weeks we have been working hard on the software for the Retro-Printer module to meet ongoing demands of various industrial customers (and some home users).
www.retroprinter.com

Recent requirements have been:

a) Capture output from PLC machines and echo it via either TCP/IP or JSON to the SCADA screens
b) Capture data from sensing equipment and convert it to a CSV file for longer term processing and storage
c) Capture the weights from a set of scales and produce barcode labels
d) Create a PDF of a graph produced by sampling equipment which normally prints to an Epson Colour Photo printer - that needed a special colour mode
e) Work out why a PCX file printed from Kid Pix 1.0 under DOS printed in a shade of green, rather than black & white. Only to find that when printed from Paintbrush under Windows for Workgroups it printed correclty in black & white,

Certainly a lot of different applications for our rather humble device - thankfully we enjoy the challenge of writing in C.

The Retro-Printer provides low cost printer port capture hardware to capture data and connect computers & industrial equipment to modern printers.