centronics interface schematics???

[Peter]

MPS from Richard Urena just makes a PostScript file out of an ASCII text file. Usual ESC/P2 output from QL setups may require more than that.

[bwinkel67]

I have a US Miracle Centronics Interface. It looks different:

Oh, I have a USB one next to it that I bought a few years ago when I upgraded my desktop and still had an old parallel laser printer.

[RWAP]

Plain text, HTML and Postscript is probably not what Derek wanted.
But there is a Raspberry open source project for converting Epson ESC/P and ESC/P2 dot matrix and inkjet printer data, too. Which is, as far as I know, the basis of the Retro-Printer Derek mentioned.

The Retro-Printer hardware is designed to replace a centronics printer, so incorporates a centronics interface of course. At some point we may need to bring out a serial port version - industry tends to want some indication as to what is going on and control over it, not necessarily just a software control on serial port settings either, so the hardware remains useful even in a serial only version.

Yes, there is an open source project for converting ESC/P and ESC/P2 printer data - it is our own conversion program used by the Retro-Printer (or at least a subset of it).
As Derek says, we also convert plain text and PCL data and offer multiple output options.

The serial GPIO pins on the Raspberry Pi are possibly too slow to be honest for some of the printer data unless you buffer it (and are used by the Retro-Printer interface). Yes a serial to USB adaptor could be another option.

[Derek_Stewart]

I have a US Miracle Centronics Interface. It looks different:

Centronics.jpg

Oh, I have a USB one next to it that I bought a few years ago when I upgraded my desktop and still had an old parallel laser printer.

Hi,

The Miracle Serial to Parallel interface is not a specific US marketed interface.

This was the next version, in the Miracle Interface, I have one in use , but has a QL connector , rather than a DB9 connector.

The new interface was a major change in the way the converter was made.

I remember organising a QL Show in the North East of England, in the 1990s, where Stuart Honeyball wanting lots of publicity to promote this new product.

[Peter]

The serial GPIO pins on the Raspberry Pi are possibly too slow to be honest for some of the printer data unless you buffer it (and are used by the Retro-Printer interface).

I don't understand what you mean here. How could the Raspberry UART be too slow to receive data from a QL (or even Q68) SER port?

Derek uses a SER port, connects it to a Miracle Centronics adaptor, and goes from there to the Retro Printer module on a Raspberry. I just thought this could be simplified to directly connect the SER port to the Raspberry, omitting the Miracle adaptor and the Retro Printer module.

[RWAP]

It is not the UART - it is the GPIO pin transmission - the serial pins are the i2c pins so far as I understand.

I am not a hardware guy (the hardware is designed by Sascha Heinisch) - I just recall that we found we needed to buffer the data to get it over the GPIO pins without losing some of the data (admittedly we are having to read several more pins for the Retro-Printer module than just the serial i/o).

A QL serial lead connected to a serial to USB adapter works too so yes, you can use a QL serial lead with the Raspberry Pi and conversion software if you want. We just don't support it because obviously, the Retro-Printer is a commercial product.

[Artificer]

RWAP wrote
The serial GPIO pins on the Raspberry Pi are possibly too slow to be honest for some of the printer data unless you buffer it (and are used by the Retro-Printer interface).

I am using a serial to serial cable to print files from a Q68 and Q60 through my RPi to a remote wifi printer. Baud used is 19200. As the slowest part of the process is CUPs on the Rpi rendering the file to code for the printer and the printer itself printing I have not bothered to try a higher baud rate. I use a serial Pi hat.

Peter wrote
MPS from Richard Urena just makes a PostScript file out of an ASCII text file.

Indeed but the SBasic version of this program from Marcel Kilgus has been adapted to convert Quill doc files to postscript for printing via the serial to serial connection between my Q68 and RPi.

Cheers

[bwinkel67]

This was the next version, in the Miracle Interface, I have one in use , but has a QL connector , rather than a DB9 connector.

The new interface was a major change in the way the converter was made.

Very compact design. I'll have to take a peek inside of it at one point.

[Peter]

It is not the UART - it is the GPIO pin transmission - the serial pins are the i2c pins so far as I understand.

GPIO would not be used, as the Retro printer board is not needed when no parallel port data is involved.

I just ment to skip the steps SER-PAR, PAR-RetroPrinter and RetroPrinter-RPi. And go SER-RPi instead.

[Derek_Stewart]

Hi,

I also use the Miracle Serial to Centronics adapter connected to the Retro-Printer adapter for the Raspberry PI, which connects into my CUPS printer server on a Linux Raid server, becase I already have them.

The other fact, is I very seldom print anything out these days, only packing lists and shipping labels.

The Raspberry PI can indeed be connected to other computers via the serial port connection accessed by the GPIO pins. I do not seem to find a use for this, as the Raspberry PI, while good product at a low price, is a slow Linux computer compared to the Core i5 computers I have running my Virtual network server.

Before any starts crying how good the Raspberry P, is I mainly use a PI 2B+ for RISC OS, which is on a par with Linux, maybe RISC OS is better but there are more free software on Linux.