[Info-vax] DZQ11 on VAX/4000 Model 300

[johnwallace4 at yahoo.co.uk]

On Tuesday, 15 January 2019 00:28:55 UTC, David Wade  wrote:
> On 14/01/2019 23:25, johnwallace4 at yahoo.co.uk wrote:
> > On Monday, 14 January 2019 21:19:24 UTC, David Wade  wrote:
> >> On 14/01/2019 17:42, Stephen Hoffman wrote:
> >>> On 2019-01-14 17:04:41 +0000, David Wade said:
> >>>
> >>>>    I have just installed a DZQ11 in my VAX/4000 and once I figured out
> >>>> I had by "A" and "B" pins mixed up on the BERG connector  (I had to
> >>>> fabricate a lead as it came without any) on a brief test it seems to
> >>>> be working just fine.
> >>>>
> >>>> However when I removed it the VAX seemed to hang on boot. I popped it
> >>>> back in and it seems to be working fine.
> >>>
> >>>> So should I do anything to VMS to manage its configuration?
> >>>
> >>> Nope.  OpenVMS is working exactly as expected.
> >>>
> >>
> >> Why does it hang when the card is removed? Thats not expected to me...
> >> .. if the CSRs worked before, surely they work the same afterwards....
> >>
> >>>> In case it matters the machine is running VMS 7.3. The other cards in
> >>>> the machine are, from the CPU and memory moving left, a TK70
> >>>> controller card, a KZQSA SCSI controller with CD ROM and the DZQ11.
> >>>>
> >>>> Please excuse me asking on here but google seems to be intent on
> >>>> referring me to hpe sites which all redirect to the documentation Index.
> >>>
> >>> HPE is exiting the OpenVMS business.
> >>>
> >>
> >> Then why does it still have the documentation catalogue ...
> >>
> >>> Use Google Groups search of the comp.os.vms newsgroup archives, search
> >>> for the word "serpentine" (though that's less of an issue with BA213 and
> >>> BA215 and BA4xx series Q-bus boxes), and learn how the Q-bus and the
> >>> Q-bus boards are configured.
> >>>
> >>
> >> The BA440 backplane isn't a serpentine plane is it?
> >>
> >>> Basically, the Q-bus CSRs and vectors can vary by what's installed in
> >>> the Q-bus in the box, and you'll need to adjust the CSR and (if present)
> >>> vector settings on one or more other Q-bus modules in the bus, and/or
> >>> insert a bus grant card or otherwise fill the vacated slot.
> >>>
> >>> Start by reading chapters 3 and 4 here:
> >>> https://archive.org/stream/bitsavers_decvax630AITechnicalManualBA23EnclosureOct85_15635013/AZ-GLFAB-MN_VAXstation_II_Technical_Manual_BA23_Enclosure_Oct85#mode/2up
> >>>
> >>
> >> That is a Serpentine backplane isn't it? Frome reading the VAX/4000
> >> manual the BA440 isn't a serpentine backplane. The CD slots are seem to
> >> be generally only used for memory and there is no
> >>
> >>>
> >>> Oh, and ********NEVER********** believe the interrupt vector setting
> >>> shown by OpenVMS.   Be skeptical about the CSR setting, too.
> >>> OpenVMS VAX will tell you what it thinks or expects the vector to be,
> >>> and that may not match reality.
> >>> OpenVMS VAX has no direct means of reading the interrupt vector setting,
> >>> and the indirect means is dicy at best and is not implemented by OpenVMS
> >>> displays.
> >>> Again, ********NEVER, EVER, EVER, UNDER NO CIRCUMSTANCES, DO NOT EVEN
> >>> THINK OF IT, NOT-AT-ALL, NOPE, DO NOT MAKE THIS MISTAKE******** trust
> >>> what OpenVMS VAX shows for CSR and particularly vector settings.
> >>> Remove the boards, and decode the CSR and (if present) the interrupt
> >>> vector setting.
> >>>
> >>> And FWIW, Google seemingly doesn't include the Google Groups content in
> >>> most Google searches.  Only the Google Groups search seemingly includes
> >>> that data from here in the newsgroup, and that Google Groups search
> >>> doesn't always work reliably.
> >>>
> >>>
> >>>
> >> It sometimes pops up....
> >>
> >> Dave..
> > 
> > Without seeing some more info on what happens in the (failed)
> > boot process it's hard to be helpful. Are you using a serial
> > console whose output can be captured and posted somewhere?
> > 
> 
> Yes
> 
> > Also there is no such thing as VAX/4000, there are various
> > VAX 4000 family members of different shapes and sizes and
> > capabilities.
> > 
> 
> VAX 4000 model 300
> 
> > To the best of my recollection very few (none?) of them were
> > sold in a BA23-type box with the BA23-associated mixed Q/CD
> > backplane. See e.g.
> > https://en.wikipedia.org/wiki/VAX_4000
> > 
> > Also look elsewhere on t'Interweb for references to BA440
> > enclosure which was frequently used for VAX 4000, (or even
> > look at the manufacturer label on your own enclosure) so
> > readers can have a better idea of what's in the box, which
> > should help provide better responses to your questions.
> > 
> 
> Its a BA440
> 
> > Is there any chance that the addition of the DZQ card in the
> > "VAX/4000" has done something which persists after the card
> > is removed? As you rightly point out, it's not unreasonable
> > to expect the "orignal" behaviour to be restored when the
> > DZQ is removed, if it's purely related to CSRs and vectors
> > etc. However...
> > 
> > Let's suppose (for example - not suggesting that this is
> > what's happening here, insufficient data to rule it in or
> > rule it out) the insertion of the DZQ makes something visible
> > that was previously invisible.
> > 
> > Also suppose that newly visible something is VMScluster-related
> > and contributed to votes (lots of VAX 4000 systems had DSSI
> > connected storage. DSSI disks could and did sometimes
> > contribute to cluster votes, and in the right circumstances
> > that change could lead to an increase in E
> > 
> > Suppose also that removing the DZQ makes that something go
> > away, and that it reappears when the DZQ is put back in,
> > either because of changed CSR/vectors or changed grant
> > continuity or whatever.
> > 
> > If it's having an effect on cluster formation, votes, etc,
> > it ought to be reasonably obvious from a boot-time console
> > log, if it was happening.
> > 
> 
> Its not clustered
> 
> > Or this could be irrelevant to your setup. Right now it's hard
> > to say, but a little more detail on what you've actually got
> > might well be useful.
> > 
> > Best of luck. Have a lot of fun.
> > 
> 
> The detail seems to have got lost in the trimming.....
> 
> So a VAX 4000 model 300 as described here:-
> 
> http://manx-docs.org/collections/mds-199909/cd1/vax/337abti2.pdf
> 
> The technical manual for the BA440 as described in this manual...
> 
> http://manx-docs.org/collections/mds-199909/cd2/cabinets/348abmg2.pdf
> 
> There are usually two additional cards in the Q-BUS, a TK70 tape 
> controller card, which does not have a tape drive connected, and which 
> sits next to the CPU. A KZQSA SCSI controller, which gain usually has no 
> drives connected, but which is used to connect a CD-ROM, which sits in 
> the next slot.
> 
> I have a selection of Pen Plotters that I wanted to experiment with so I 
> wanted some extra Serial Ports. So I bought a DQZ11. It was cheap enough 
> so if it didn't work it was not a big deal.
> 
> I can say the system works fine.  I have only run limited tests, but it 
> boots, TCPIP works and I can log on using the DZQ11. If I then remove 
> the DQZ11 the system won't boot normally, which I found puzzling, and 
> wondered why and what to do about it.
> 
> I will try and reproduce with a PC console so I can capture the startup 
> log...
> 
> Dave

OK, thanks for that.

Your console logging doesn't necessarily *require* a PC, but 
if it's readily available and familiar, fair enough. Other 
options might include connecting to the VAX 4000M300 console 
via a terminal server port and "reverse LAT" or similar (if 
that means anything to you).

Whichever approach you pick for console port connectivity, 
something you might want to look at sooner rather than later
might be the console-mode 
"SHOW QBUS" command, 
It's described in various manuals including the VAX 4000 
Model 300 Technical Info Guide, EK-337AB-TI (you have access 
to this one, right?).

Try it both with and without the DZQ card present, and see if any 
differences are visible.

As others have noted, and as can be seen from the DZQ docs,
the DZQ11 isn't designed to be a high performance serial card.
Add the VAX/VMS terminal driver(s) on top, and anything much 
more demanding than mainstream interactive use might be a bit 
too much to ask.

But maybe we're not at that stage yet. 

The pen plotters you have, are they later-era stuff that 
understands e.g. HPGL-style, where relatively simple ASCII
commands can be fed to the plotter and the plotter does
further computation to e.g. plot an ellipse from a simple
set of commands from its host? (The kind of stuff that 
might be associated with VAX GKS? e.g. as seen at
https://softsolder.com/2015/04/20/hp-7475a-plotter-rehabilitation/
Some readers may recognise a similarity between an
HP7475A and a DEC LVP16).


Or if you're looking at e.g. so-called "incremental" plotters
which essentially rely on a continuous stream of (often binary)
pen-movement commands, because e.g. the plotter itself doesn't 
have the brains to calculate an ellipse's co-ordinates in 
realtime (y'know, late 1970s or early 1980s stuff), you may 
well find that the DZQ and the usual VMS terminal driver are 
not ideal. Or it might be OK. YMMV.

But again maybe that's for later. Meanwhile, best of luck
with your quest.