On 3/6/21 9:59 AM, Scott Quinn via cctalk wrote: > Realized I didn't post the project I was looking at just in case others > were interested: > > https://tudl1910.home.xs4all.nl/rshockley.dyndns.org/indigo.htm > > Converter to use PS/2 keyboards with SGI Indigo, Onyx, Crimson and 4D > series machines. > Not my page, not my project, not my work (yet).
Way overkill for the job, IMHO. Drop the crystal and use a smaller 8 pin PIC12 MCU--the internal RC clock is more than good enough. It should be possible to do the same using a Blue Pill cheapie and MAX232 level shifter. Still if this is a one-off, I doubt that it would matter to the user. FWIW, I did the PC AT/PS2 to PC XT keyboard converter years ago using the cheapest PIC I could find--a 12F629--and I still had program memory left over. A cap, a diode and a resistor were the only external components. --Chuck