26 Feb
1999
26 Feb
'99
8:51 a.m.
Howdy, I've taken delivery on two MicroVax II's, one is a model 630QY-A2
and the other is a 630QB-A2, the QY is basically a narrow cabinet and the
QB is a wide cabinet. Both have 8MB and both have ethernet controllers.
Both were stripped of drives although one still has a tape unit. (TK50? How
can I tell?)
Here are the questions:
1) I'd like to find a disk or two for these (they each have slots for four
disks of the DU type.) what do I need to look for? Are there size limitations?
2) Can these things be booted over the network in a pinch? (one has no tape
drive)
2b) Do these things have boot roms that are interactive ala ODT? Until I
get disks is there anyway to verify that they work?
3) Would it make sense to combine the memory cards so that I have one 16MB
VAX or should I leave it at two VAXen?
4) One has a busextender unit that goes to a non-DEC disk card labelled:
"Wombat" (its a disk controller of some sort) with tag WQESD 2.8M
SCD-RQD11/EC
a) This is ESDI controller yes?
b) It has four data connectors so four drives?
c) Its in a different backplane UNIBUS perhaps? (quad height)
Both machines internally appear to be in very good shape. Anyone have the
"MicroVAX II 630 QB Technical Manual" ?
All in all it wasn't a bad deal at $18 each.
--Chuck
26 Feb
26 Feb
9:55 a.m.
Chuck McManis <cmcmanis(a)freegate.com> wrote:
Both machines internally appear to be in very good
shape. Anyone have the
"MicroVAX II 630 QB Technical Manual" ?
I don't have that one, but I did (*finally*, after years of wanting one)
manage to get a KA630 CPU Module User's Manual (probably not the exact
title since that's from memory).
Now I need to find a similar manual for the KA650 and/or KA655.
Speaking of such things, can anyone explain how the memory cards in a
MicroVAX II or III know where to map themselves? They don't have DIP
switches or jumpers, and neither the backplane nor the ribbon cable
seem to provide any distinct signals per slot, except maybe bus grant and
I don't see how they would use that.
Eric
1:20 p.m.
Both were stripped of drives although one still has a
tape unit. (TK50? How
can I tell?)
Is it completely plain? If so it's a TK50. Yeh, I know that's vague.
1) I'd like to find a disk or two for these (they
each have slots for four
disks of the DU type.) what do I need to look for? Are there size limitations?
Depends on the controller. If using a RQDX3 you're limited to DEC disks,
or at least disks that have been made to look DEC.
2) Can these things be booted over the network in a
pinch? (one has no tape
drive)
Hmmm, I think so. My VAXstation II/RC was trying to do this when I got it.
Same basic computer.
2b) Do these things have boot roms that are interactive
ala ODT? Until I
get disks is there anyway to verify that they work?
The ROMS on a MV2 aren't very smart. Check here for a lot of answers to
your questions. http://anacin.nsc.vcu.edu/~jim/mvax/mvax_faq.html
3) Would it make sense to combine the memory cards so
that I have one 16MB
VAX or should I leave it at two VAXen?
If it was me, I'd do that and use the other cabinet for a PDP-11, but that
assumes you need a cabinet for a PDP-11.
4) One has a busextender unit that goes to a non-DEC
disk card labelled:
"Wombat" (its a disk controller of some sort) with tag WQESD 2.8M
SCD-RQD11/EC
a) This is ESDI controller yes?
b) It has four data connectors so four drives?
c) Its in a different backplane UNIBUS perhaps? (quad height)
Wierd, I've got mine plugged directly into the backplane. WUESD I think is
the
designation of the UNIBUS version. You've got the Q-Bus version, it's an
AWSOME card! It will run 4 ESDI drives, and has all kinds of cool features.
All in all it wasn't a bad deal at $18 each.
Good haul, the WQESD makes it definitly worth it. ESDI drives are easy to
find cheap, though it might take some time. Their definitly better to use
than the MFM drives that are standard on the MVII's.
Zane
| Zane H. Healy | UNIX Systems Adminstrator |
| healyzh(a)aracnet.com (primary) | Linux Enthusiast |
| healyzh(a)holonet.net (alternate) | Classic Computer Collector |
+----------------------------------+----------------------------+
| Empire of the Petal Throne and Traveller Role Playing, |
| and Zane's Computer Museum. |
| http://www.dragonfire.net/~healyzh/ |
1:51 p.m.
Hi Chuck/List:
Howdy, I've taken delivery on two MicroVax
II's, one is a model 630QY-A2
and the other is a 630QB-A2, the QY is basically a narrow cabinet and the
QB is a wide cabinet. Both have 8MB and both have ethernet controllers.
Both were stripped of drives although one still has a tape unit. (TK50? How
can I tell?)
Likely a TK50, as the TK70 (newer) drive say "TK70" on the front panel.
TK50 has a 3" by 1" slot (approx), and one red button on the right hand
side of the drive. You could also tell by getting the M number of the
controller.
1) I'd like to find a disk or two for these (they
each have slots for four
disks of the DU type.) what do I need to look for? Are there size limitations?
Generally an older MFM disk. These work with the semi-standard RQDX3
controller. Micropolis 1325, 1355, or similar. 100 or 300 MB
approximately. You can also use ESDI disks but you'll need an Emulex QD21
controller. If you find some SMD drives, then an Emulex QD32 or QD33 will
work really well. There are SCSI controllers but they're expensive and
very hard to find.
2) Can these things be booted over the network in a
pinch? (one has no tape
drive)
Sure. Just say B XQA0 at the chevron ( >>> ) prompt. Of course you'll have
to have another machine set up to boot from. I've booted my Microvax II
into both VMS and NetBSD this way.
3) Would it make sense to combine the memory cards so
that I have one 16MB
VAX or should I leave it at two VAXen?
With memory more is usually better, but you can get good mileage out of 8
MB so leave it alone until there's need to expand. It depends as well on
how the memory is linked to the CPU board, there is a separate bus for
some cards. Best to leave it at 8 MB until you learn more.
All in all it wasn't a bad deal at $18 each.
I'll say. Great deal!
Kevin
--
Kevin McQuiggin VE7ZD
mcquiggi(a)sfu.ca
1:53 p.m.
Speaking of such things, can anyone explain how the
memory cards in a
MicroVAX II or III know where to map themselves? They don't have DIP
switches or jumpers, and neither the backplane nor the ribbon cable
seem to provide any distinct signals per slot, except maybe bus grant and
I don't see how they would use that.
Basically, the address is passed to the first board. If the address is
in the range it can handle, it responds and that's it. If not, it
subtracts its size from the address and passes it on to the next board.
If the modified address is within the range of memory you have installed,
eventually one of the boards will see the address as an address between
zero and it's size, and respond. If no board responds (and the address
falls off the end, so to speak), then the processor times out and you
get a non-existent memory response/trap.
Megan Gentry
Former RT-11 Developer
+--------------------------------+-------------------------------------+
| Megan Gentry, EMT/B, PP-ASEL | Internet (work): gentry!zk3.dec.com |
| Unix Support Engineering Group | (home): mbg!world.std.com |
| Compaq Computer Corporation | addresses need '@' in place of '!' |
| 110 Spitbrook Rd. ZK03-2/T43 | URL: http://world.std.com/~mbg/ |
| Nashua, NH 03062 | "pdp-11 programmer - some assembler |
| (603) 884 1055 | required." - mbg |
+--------------------------------+-------------------------------------+
2:02 p.m.
I wrote:
> Speaking of such things, can anyone explain how
the memory cards in a
> MicroVAX II or III know where to map themselves? They don't have DIP
Megan replied:
Basically, the address is passed to the first board.
If the address is
in the range it can handle, it responds and that's it. If not, it
subtracts its size from the address and passes it on to the next board.
If the modified address is within the range of memory you have installed,
eventually one of the boards will see the address as an address between
zero and it's size, and respond. If no board responds (and the address
falls off the end, so to speak), then the processor times out and you
get a non-existent memory response/trap.
This would make sense to me if the wiring was such that there were separate
address busses from the CPU to the first memory card, the first memory
card to the second memory card, etc.
But as far as I can tell, all of the signals are simply bussed in parallel
to all of the memory cards. That's what I find baffling.
Obviously there is a very simple explanation which I am overlooking.
27 Feb
27 Feb
6:10 a.m.
A non-text attachment was scrubbed...
Name: not available
Type: text
Size: 1167 bytes
Desc: not available
Url :
http://www.classiccmp.org/pipermail/cctalk/attachments/19990227/14ecdf5a/at…
8:21 a.m.
Tony wrote:
I'd always assumed it used the CD-interconnect
between the first 3 slots
on the MicroVax backplane. Those signals are wired from one slot to the
next, and aren't bussed between all the slots.
Oh, that would explain it then. The docs I have (which don't include prints)
seem to imply that the C/D interconnect is bussed.
Thanks!
Eric
9:20 a.m.
A non-text attachment was scrubbed...
Name: not available
Type: text
Size: 843 bytes
Desc: not available
Url :
http://www.classiccmp.org/pipermail/cctalk/attachments/19990227/3f09226d/at…
26 Feb
26 Feb
2:18 p.m.
This would make sense to me if the wiring was such that
there were
separate address busses from the CPU to the first memory card, the first
memory card to the second memory card, etc.
But as far as I can tell, all of the signals are simply
bussed in
parallel to all of the memory cards. That's what I find baffling.
I simplified a little.
There are some extra signals which are also bussed which carry info
between boards... like whether the address was handled by the first
board or not. If so, then the second doesn't respond. If not, then
the second does the address adjustment and see if it should respond.
Megan Gentry
Former RT-11 Developer
+--------------------------------+-------------------------------------+
| Megan Gentry, EMT/B, PP-ASEL | Internet (work): gentry!zk3.dec.com |
| Unix Support Engineering Group | (home): mbg!world.std.com |
| Compaq Computer Corporation | addresses need '@' in place of '!' |
| 110 Spitbrook Rd. ZK03-2/T43 | URL: http://world.std.com/~mbg/ |
| Nashua, NH 03062 | "pdp-11 programmer - some assembler |
| (603) 884 1055 | required." - mbg |
+--------------------------------+-------------------------------------+
5:01 p.m.
Megan further explained my uVAX II question:
There are some extra signals which are also bussed
which carry info
between boards... like whether the address was handled by the first
board or not. If so, then the second doesn't respond. If not, then
the second does the address adjustment and see if it should respond.
OK, except that I still don't understand. It looks like ALL of the signals
are bussed straight across, except the bus grant. So I still don't see
how the first card knows that it is first, and why the second card doesn't
erroneously think that it is first.
9430
days inactive
9431
days old
10 comments
6 participants
participants (6)
-
ard＠p850ug1.demon.co.uk -
cmcmanis＠freegate.com -
eric＠brouhaha.com -
healyzh＠aracnet.com -
mbg＠world.std.com -
mcquiggi＠sfu.ca