/diy/ - Do It Yourself

I've been trying to adapt an old electronic typewriter keyboard to usb. I mapped the original pcb, figured out it's pulsed via a demultiplexer, then mapped each key with a dmux input and a 5 bit output to the original mcu. I wanted to use as much of the original electronics as possible and as it sits, only the old NEC chips needed to be pulled.

I wasted like a week trying to get an NXP ARM mcu working for hid then said fuck it and went to an Arduino, only I couldn't put the usb serial bootloader on to one uno, and couldn't get it off the other to program it, so I'm programming the blue uno with the black uno via Arduino as ISP.

So far I have most keys except modifiers working but response time is shit so I have some actual usb ready avr boards in the mail to continue this with a little more grace.

I doubt it will be a practical keyboard but once I make a case for it, it will sure be a conversation piece.