> > > I have no idea what "3011-cf" is. Isn't it just a a DD11-C backplane with > power-wring entering from the back, rather than through small circuit > boards? > > > > > > UNIBUS 10 A-B (LEFT SIDE OF UNIBUS) > > M7856 10 F-C (RS232 WITH 19.2 OPTION?) > > G7273 11 C-D > > 7891 12 A-F (64k MEMORY) > > M9312 13 A-B (ROM CARD) > > 672A 13 D (GRANT CONT.) > > > > That looks like a reasonable setup provided that jumpers W1- W5 are > installed on the M9312. You should be able to install the RL11 in slot 11 > when you remove the G7273. Make sure that the wire-wrap between CA1-CB1 is > cut on slot 11 if you install the RL11 there. Also make sure that CA1-CB1 > wire-wrap jumper is installed in slot 13 (or install G7273 card in 13C-D) > > > > > I am going to switch to another backplane and start over. Don't know > what > > I am doing yet to be honest. I have to read the manuals and get better > > educated to properly get these parts working together correctly. > > > > But all this still doesn't now explain the problem that you cannot access > (or send characters to) the serial port. It could very well be the power > problem as Noel suggested. If I were you I would try to get back to the > state where it worked, shortening the Unibus to just include the 4-slot > back plane and the CPU backplane and also remove the RL11 for now. Then > install the RL11 in slot 11 when everything is working. > > /Mattis > > > I removed the core backplanes and returned the DD11-C to the orig config next to the CPU. I re-inserted cards as-was. I am not getting comms from the M7856. I may have shorted the card. So, I will work on that for now. "One step back"
thanks b