HP printers are conceptually quite simple devices, the printer just moves the cartridge and the paper. The cartridge does all the actual printing. So you reverse engineer the pinout on the cartridge and you can make your 3d printer do normal printing. That’s also how those little handheld cube printers work.
You can start here: https://hackaday.io/project/176931-hp-printer-cartridge-control-module/details
HP printers are conceptually quite simple devices, the printer just moves the cartridge and the paper. The cartridge does all the actual printing. So you reverse engineer the pinout on the cartridge and you can make your 3d printer do normal printing. That’s also how those little handheld cube printers work.