On Thu, Oct 8, 2020 at 3:39 PM Noel Chiappa via cctalk <cctalk@classiccmp.org> wrote: > > From: Ethan Dicks > > > a DEC sync serial board since that part is nowhere to be found right > > now. > > I dunno, I see them fairly often on eBait (well, often compared to some other > things, e.g. TU56 parts... :-)
"Part" in this case is "part of the whole", not "computer part"... The part that is missing in that paragraph is code for Simh that emulates a DEC sync serial board. Real DEC sync serial boards aren't that hard to find because almost nobody has a use for them. > QBUS or UNIBUS? And there are lots of different ones, which I confess I don't > fully understand the difference between (e.g. DP11, DQ11, DU11, DUP11, DV11) - > some of it's single-line/multi-line, and DMA/programmed I/O, but from what few > details I looked at - while doing: Yes. There are many varieties, both Unibus and Qbus. They have different serial chips and different host-bus register sets, which is why I said first one needs to identify which application is to be used, _then_ choose which board to emulate (or purchase for real hardware). > there are also differences in exactly which protocools are supported, > etc, etc, etc, etc. Yes. It all matters. This stuff used to be hard. People used to give us $25,000 to solve the problem. -ethan