I have two bad memory boards and could use some advise on how to repair them.
The first is an MSV11-PL 512KB-Q-Bus 22bit. Dead to both CSR and Memory address access in ODT. Was working until a short time ago. Checked all the jumpers and no evidence any magic smoke has been released. I have a copy of MP01239_MSV11-P Field Maintenance Print, but before start poking around with my scope I wonder if someone has seen this before and/or can recommend a particular methodology to finding the fault. The second board is a CMV1000 that probably has a bad Memory Chip. The results of CVMJAB0 point to “Bank 35”. I don’t have either prints or a manual for this board. Partial report follows: 512K OF Q-BUS PARITY MEMORY 512K WORDS OF MEMORY TOTAL MEMORY CONFIGURATION MAP 16K WORD BANKS 1 2 3 4 5 6 7 012345670123456701234567012345670123456701234567012345670123 ERRORS X MEMTYPE PPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPP CSR 00000000000000000000000000000000 PC BANK VADD PADD GOOD BAD XOR CSR MTYP INT PAT 025770 35 157752 03577752 000377 03577752 03577752 0 P 17 025770 35 157712 03577712 000377 03577712 03577712 0 P 17 025770 35 157652 03577652 000377 03577652 03577652 0 P 17 025770 35 157612 03577612 000377 03577612 03577612 0 P 17 025770 35 157552 03577552 000377 03577552 03577552 0 P 17 024564 35 141612 03561612 061612 03561612 03561612 0 P 01 024564 35 141652 03561652 061652 03561652 03561652 0 P 01 024564 35 142712 03562712 062712 03562712 03562712 0 P 01 024564 35 143712 03563712 063712 03563712 03563712 0 P 01 024564 35 143752 03563752 063752 063752 000000 0 P 01 024564 35 145552 03565552 065552 03565552 03565552 0 P 01 024564 35 145652 03565652 065652 065652 000000 0 P 01 024622 35 141412 03561412 116365 03561412 03561412 0 P 02 024622 35 141452 03561452 116325 03561452 03561452 0 P 02 024622 35 141512 03561512 116265 03561512 03561512 0 P 02 024622 35 141552 03561552 116225 03561552 03561552 0 P 02 I was expecting bad and xor to be 16bit values, but they appear to be mostly 22bit addresses. But then again this isn’t a DEC board. The board itself is labeled with bits 0-7 P0 P1 8-15 across the top and 8 rows of chips (MT4264-15). Any suggestions as to which chip might be suspect? Jerry