Hey guys, I’m interested in using this print head for a clothing printer.
I have a sneaky idea for a much easier way to reverse engineer the print head which should work assuming the print head is direct driven.
Simply take a microcontroller with a 5us pulse with 10ms or so interval on a digital out pin running through an npn transistor (determine required voltage from the hp printer with a scope)
Then you can just run two probes and randomly connect them to print head contacts that have reasonable resistance between them and see which nozzles fire.
I’ve ordered a printer with the C642a printhead, hopefully I’ll get time to work on it soon.