Partially garbled output with default install

[keenerb]

RPI4, retroprinter module v4, using rpi3.19d compressed image. Application is Printmaster 1.0 configured for an EPSON FX nine-pin printer.

The computer prints fine to an actual Epson LX-350 and LQ-800 printers, but output with retroprinter is about 40% garbled.

2023-09-09 20_49_58-Retro-Printer_2023-09-10_011555-6.pdf and 7 more pages - Personal - Microsoft​ E.png (105.33 KiB) Viewed 2417 times

Also attached the raw file.

I tried tinkering with signal_time and printer_delay, only seemed to make things worse.

[keenerb]

Epson text output looks pretty flawless from the few samples I printed.

HP emulation displays a similar issue with a different print app, Printmaster Gold for MSDOS:

2023-09-09 21_54_42-RP_2023-09-10_025316.pdf and 3 more pages - Personal - Microsoft​ Edge.png (114.89 KiB) Viewed 2416 times

[keenerb]

OK changing handshaking from 0 to 1 fixed it I believe!

[RWAP]

Yes, corruption is most likely down to handshaking (which affects the order in which the various signals are sent).

0 (the default) uses the standard shown as per various centronics diagrams, but oddly setting it to 2 seems to work in most cases where there is corruption.