From Barton.Bruce@camb.com Tue Aug 23 08:04:57 PDT 1994 Article: 2817 of vmsnet.pdp-11 Path: nntp-server.caltech.edu!elroy.jpl.nasa.gov!swrinde!howland.reston.ans.net!europa.eng.gtefsd.com!MathWorks.Com!noc.near.net!eisner!bruce From: Barton.Bruce@camb.com (Barton F. Bruce / CCA) Newsgroups: vmsnet.pdp-11,alt.sys.pdp11 Subject: Re: PDP-11/73 Cabling Questions Message-ID: <1994Aug22.212256.5026@eisner> Date: 22 Aug 94 21:22:56 -0400 References: <32peitINNp95@umbc8.umbc.edu> <32qtl9INN2sm@umbc8.umbc.edu> <1994Aug17.002524.1@spcvxb.spc.edu> Organization: Cambridge Computer Associates, Inc. Lines: 26 Xref: nntp-server.caltech.edu vmsnet.pdp-11:2817 alt.sys.pdp11:296 In article , mbg@world.std.com (Megan) writes: > > Another point about the 11/83 - it is additionally defined as a > KDJ11-B with PMI memory. Even if you have a KDJ11-B (18mhz and FPA), > if the system doesn't have PMI memory, it won't be considered an > 11/83 by system software. > > This is what we in RT-11 Engineering were told by the hardware group > that developed the board. That's why if you look in the sources > for RESORC, you will find code which flushes the cache hit/miss > register, then does a couple of NOPs, which on a system with PMI > will cause some ones to be shifted in. If the hit/miss register > is non-zero after the NOPs, it's an 11/83 - with PMI. I thought ALL of the quad wide 11/73 class boards were PMI capable and that DEC simply did not want you to know that by moving the CPU down a few slots and stuffing the PMI memory in ahead of it (all on a Q-CD backplane, of course), you got the PMI functionality. Otherwise sticking vanilla 22 bit Q bus memory after the processor gave you a 'non-PMI' machine. There are some Tech OEM "Micronotes" on Decuserve that Ozzi Perez kindly provided on a TK50 ages ago that cover some of this. There are lots of 73s out there not in the first slot. From mbg@world.std.com Tue Aug 23 08:05:06 PDT 1994 Article: 2818 of vmsnet.pdp-11 Newsgroups: vmsnet.pdp-11,alt.sys.pdp11 Path: nntp-server.caltech.edu!elroy.jpl.nasa.gov!swrinde!cs.utexas.edu!uunet!world!mbg From: mbg@world.std.com (Megan) Subject: Re: PDP-11/73 Cabling Questions Message-ID: Organization: The World Public Access UNIX, Brookline, MA References: <32peitINNp95@umbc8.umbc.edu> <32qtl9INN2sm@umbc8.umbc.edu> <1994Aug17.002524.1@spcvxb.spc.edu> <1994Aug22.212256.5026@eisner> Date: Tue, 23 Aug 1994 03:52:42 GMT Lines: 20 Xref: nntp-server.caltech.edu vmsnet.pdp-11:2818 alt.sys.pdp11:297 Barton.Bruce@camb.com (Barton F. Bruce / CCA) writes: >I thought ALL of the quad wide 11/73 class boards were PMI capable >and that DEC simply did not want you to know that by moving the CPU >down a few slots and stuffing the PMI memory in ahead of it (all >on a Q-CD backplane, of course), you got the PMI functionality. That's right. They ALL are PMI capable. I've converted many machines (including some at DECUS, back when I was going) from 11/73B to 11/83 simply by CORRECTLY ordering the boards. >Otherwise sticking vanilla 22 bit Q bus memory after the processor gave you >a 'non-PMI' machine. Exactly ... what RT refers to as an 11/73B Megan Gentry Former RT-11 Developer