In search of Three Rivers PERQ 1 Keyboard

Tony Duell ard.p850ug1 at
Fri May 1 02:10:22 CDT 2020

On Fri, May 1, 2020 at 2:18 AM Al Kossow via cctalk
<cctalk at> wrote:
> On 4/30/20 2:55 PM, Josh Dersch wrote:
> > It is, I refoamed mine for VCFPNW last year.  I can take internal pictures if it'd help anyone out.
> >
> > - Josh
> >
> can you dump the firmware? or was that already done for the PERQ emulator?
> it should be some flavor of 8048

The PERQ 1 keyboard uses a semi-custom encoder IC labelled AY-3-4592.
I suspect there is a mask ROM inside that gives the key mapping and
that it was used in other keyboards as there's a PROM (74S477) between
the outputs of that encoder and the PERQ. I have a dump of that PROM,
it's in the archive of PROMs/PALs that I sent to somebody yesterday.

The PERQ 2 keyboard is a standard-ish Keytronics thing with a serial
output. That does have a ROMless microcontoller (8035?) in it, again
I've dumped the firmware ROM.



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