On Tue, May 21, 2019 at 5:34 PM Glen Slick <glen.sl...@gmail.com> wrote: > > On Tue, May 21, 2019 at 4:56 PM Noel Chiappa via cctalk > <cctalk@classiccmp.org> wrote: > > > > Well, I verified that the LSI-11/2 should work in a Q22 backplane - > > in the sense that the only pins it tries to talk to are standard > > QBUS pins, and AF1/AH1 for SRUN. It doesn't drive BREF, which might > > cause issues in later QBUS systems. > > > > (It doesn't seem to work with Q18 memory, such as the MSV11-D. Attempts to > > write 0 to memory from ODT wind up leaving the bits in the high byte set. > > I have no idea why - anyone have any ideas? With Q22 memory, the symptoms > > are even stranger; the system hangs with the 'run' light on - even with > > the HALT switch on! Luckily I had an MMV11, and it worked OK with that.) > > Q22 memory uses BC1, BD1, BE1, BF1 for BDAL 18L, BDAL 19L, BDAL 20L, BDAL 21L > > According to the M7270 LSI-11/2 Microcomputer Module User's Guid, it > uses BC1, BD1, BE1, BF1 for SCLK3 H, SWMIB18 H, SWMIB19 H, SWMIB20 H. > > I haven't found a scan of the KD11-H Field Maintenance Print Set MP-00050.
I just found an online scan of MP00495 KD11-HA LSI11 CPU Field Maintenance Print Set. It does show SCLK3 H, SWMIB18 H, SWMIB19 H, SWMIB20 H being driven on BC1, BD1, BE1, BF1 for the M7270 LSI-11/2. So that seems like it might be an issue with Q22 memory.
