Site Update

Sun, May 10, 2026

That's all, for now, on TOPS-10. I've concentrated on the roughly pre-1975 era, using the PDP-10 KA CPU and operating system version 6.03; I may come back to this in the future and look at later versions if I find anything interesting.

Next update to this blog will be in June, where we will look at the Stanford University A.I. lab's operating system for the PDP-10, WAITS. This started out as a version of DEC's PDP-6 Monitor (which became TOPS-10) but WAITS evolved over the years to add support for experimental peripherals - display terminals, laser printers, robotics - and many interesting software features, as well as being an important platform for A.I. research.

As a taste of WAITS, here's a small demo I was involved in recently. PARRY, a chat program that mimics a paranoid patient, was written by Kenneth Colby on WAITS in 1972. Using simh, Lars Brinkhoff got PARRY running on WAITS for the first time in many years. I then got this talking to the ELIZA chat program running on CTSS, recreating a dotctor/patient dialogue done in 1973 as RFC 439. See Jeff Shrager's writeup, PARRY Parries Again, for more details.