On Dec 27, 2022, at 7:47 PM, Will Cooke via cctalk <cctalk@classiccmp.org> wrote: > >> On 12/27/2022 9:36 PM CST Chris via cctalk <cctalk@classiccmp.org> wrote: >> >> Those are for a different board. Maybe close enough? > > If you read the description it says the only difference is the clock chip, > which I believe is "fully" compatible.
That’s the difference between the PT68K1 and PT68K1A. The system featured in Peter Stark’s “Build the PT-68K” series in Radio-Electronics was actually the PT68K2, which is the version with PC-XT slots, keyboard support, and PCB size/layout. There don’t seem to be ROM images on the web site for that. They do exist on Bitsavers, look for Peripheral Technology. — Chris
