7 Sep
2016
7 Sep
'16
2:35 p.m.
From: Pete Turnbull
> The other thing that makes no sense is that the
KDJ11-B (M8190) has
> all that extra circuitry on it to support PMI, etc - all of which is
> unused in the 11/73 application! Why not just plug in a (presumably
> cheaper) M8192? In the /73 application, the two are basically equivalent.
Don't forget the LTC :-)
?? The KDJ11-A has an on-board LTC - see EK-KDJ1A-UG-001, pg. 1-7.
Otherwise, you'd need an additional bootstrap card
such as an MRV11-D
with -B2 boot ROMs, a DLVE1 (DLV11-JE) for the SLUs, something with an
LTC, and termination.
Err, the KDJ11-A has on-board termination: see MP-01890 pg. 1 of 9, on the LHS.
A BDV11 wouldn't work as it doesn't have the
ROM capability
?? The BDV11 is a ROM board?
(And it works fine in a Q22 bus; the address recognition circuitry uses BBS7,
it doesn't look at BDAL 16 and above.)
Noel
7 Sep
7 Sep
3:59 p.m.
On 07/09/2016 22:35, Noel Chiappa wrote:
So it does. I'd forgotten that!
I meant for the other end of the bus.
Yes, it has a lot of ROM sockets: it's a bootstrap/terminator/LTC card.
In fact it's the archetypal bootstrap card, the one that first had the
paging mechanisms all the others use. The problem is none of the
sockets support large ROMs, so there's a lot of fiddling to do to get a
microPDP-11 bootstrap and diagnostics in there. You have to split each
ROM into four devices, so eight in total. I'm well aware of how BBS7
works, but that's not the issue. Unless the BDV11 is modified, it
doesn't work correctly in a 22-bit system as it has 18-bit termination.
Although DEC listed the BDV11 (Rev.F only) as compatible they classed
22-bit 11/73 systems using a BDV11 of any sort as "not field
serviceable" and wouldn't supply or support any that way.
--
Pete
Pete Turnbull
From: Pete
Turnbull
Don't forget the LTC :-)
?? The KDJ11-A has an on-board LTC - see EK-KDJ1A-UG-001, pg. 1-7. Otherwise,
you'd need an additional bootstrap card such as an MRV11-D
with -B2 boot ROMs, a DLVE1 (DLV11-JE) for the SLUs, something with an
LTC, and termination.
Err, the KDJ11-A has on-board termination: see MP-01890 pg. 1 of 9, on the LHS. A BDV11
wouldn't work as it doesn't have the ROM capability
?? The BDV11 is a ROM board?
(And it works fine in a Q22 bus; the address recognition circuitry uses BBS7,
it doesn't look at BDAL 16 and above.) 
4:37 p.m.
On Wed, Sep 7, 2016 at 3:59 PM, Pete Turnbull <pete at dunnington.plus.com> wrote:
Yes, it has a lot of ROM sockets: it's a bootstrap/terminator/LTC card. In
fact it's the archetypal bootstrap card, the one that first had the paging
mechanisms all the others use. The problem is none of the sockets support
large ROMs, so there's a lot of fiddling to do to get a microPDP-11
bootstrap and diagnostics in there. You have to split each ROM into four
devices, so eight in total. I'm well aware of how BBS7 works, but that's
not the issue. Unless the BDV11 is modified, it doesn't work correctly in a
22-bit system as it has 18-bit termination. Although DEC listed the BDV11
(Rev.F only) as compatible they classed 22-bit 11/73 systems using a BDV11
of any sort as "not field serviceable" and wouldn't supply or support any
that way.
http://www.bitsavers.org/pdf/dec/qbus/oemMicronotes.pdf
uNOTE #004
LSI-11/73 Upgrade Paths
"NOTE
1. In the following upgrade scenarios, the systems have been labeled
as being Field Serviceable or not. A system which is Field Serviceable
has a bootstrap which meets Field Service requirements. The
requirement is that the bootstrap must execute an 11/73 cache memory
diagnostic on power-up. There is not guarantee that the overall system
will be Field Serviceable or that it will be FCC compliant."
Basically this boils down to having the MXV11-B2 Boot ROMs installed
on either an MXV11-B or MRV11-D. The MXV11-B2 Boot ROMs are apparently
not compatible with the BDV11, for reasons I don't remember 100% off
the top of my head.
Why are MRV11-D boards so expensive, at least on eBay? Were they sold
in relatively low volume compared to CPU boards?
5:31 p.m.
On 08/09/2016 00:37, Glen Slick wrote:
Basically this boils down to having the MXV11-B2 Boot
ROMs installed
on either an MXV11-B or MRV11-D. The MXV11-B2 Boot ROMs are apparently
not compatible with the BDV11, for reasons I don't remember 100% off
the top of my head.
Too big. They're a pair of 8K ROMs, but the BDV11 only supports 2K and
1K devices.
Why are MRV11-D boards so expensive, at least on eBay?
Were they sold
in relatively low volume compared to CPU boards?
I guess that's the reason. I've only ever seen two, but I've seen (in
fact I have) lots more earlier ROM boards and several MXV11-Bs. I
suppose by the time the MRV11-D came out, people who needed a bootstrap
paging capability either had 11/03 or 11/23 systems with BDV11s or, if
they needed an 8K bootstrap, had microPDP-11s, in which the bootstrap is
always on the CPU card. Almost anything else could use the cheaper
MRV11-C (though it only supports up to 4K chips) and even that supports
the conventional bootstrap mechanism, albeit only 16- or 18-bit, not
using BBS7.
--
Pete
Pete Turnbull
6:23 p.m.
On Wed, Sep 7, 2016 at 5:31 PM, Pete Turnbull <pete at dunnington.plus.com> wrote:
On 08/09/2016 00:37, Glen Slick wrote:
I thought there was something else beyond that, maybe the ROM
windowing scheme was different or something like that.
If it is really nothing more than the size of the MXV11-B2 ROMs of
8Kx8 being too big, then maybe it would work by splitting the ROM
images across 2Kx8 EPROMs.
People have been successful putting the KDF11-BG ROM images on a BDV11
for use with an M8186 KDF11-A by splitting the two 8Kx8 images across
eight 2Kx8 2716 EPROMs.
http://www.vcfed.org/forum/showthread.php?24754-Qbus-Memory-cards/page2
I have been meaning to try that myself sometime.
Basically this boils down to having the MXV11-B2
Boot ROMs installed
on either an MXV11-B or MRV11-D. The MXV11-B2 Boot ROMs are apparently
not compatible with the BDV11, for reasons I don't remember 100% off
the top of my head.
Too big. They're a pair of 8K ROMs, but the BDV11 only supports 2K and 1K
devices.
6:10 p.m.
New subject: Q-Bus Memory Diagnostics and Repair
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
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5 comments
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participants (4)
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glen.slick＠gmail.com -
jnc＠mercury.lcs.mit.edu -
jsw＠ieee.org -
pete＠dunnington.plus.com