On Mon, May 13, 2019 at 8:20 AM Paul Koning via cctalk <cctalk@classiccmp.org> wrote: > > There were also the AMD2901, 2903, 29203 family of bit-slice components, > > with the 2910 sequencer. > > The VAX 730 was built with 2901s.
Yep. I pulled some 2901s from a VAX 11/730 CPU board in the early 90s to repair a Tempest "Math Box" (we were doing our own repairs on our VAXen in the late 80s/early 90s, and we had a stack of dead and questionable boards in our engineering area, so one gave its life to repair an arcade machine). > On the subject of custom chips: DEC used gate arrays a lot. For example > there is the Pro 380 in which much of the discrete chip logic from the Pro > 350 has been absorbed into one or two gate arrays, with all the unnecessary > flexibility of the original chips omitted. What sort of flexibility was omitted? I have both models and the board layout difference is obvious (there's so much room on the Pro380 that it has a huge RAM field right on the mainboard instead of on two daughter cards (plus any on the CTI bus). -ethan
