Some pointers needed on a 11/70

From: The Wanderer <>
Date: Wed Jan 9 15:42:57 2002

Hello Pete,

I checked the config of the memory box, and it was already configured
according to
your notes. I also was lucky enough to find engineering diagrams of the
data buffer
and the address buffer in a pile of misc diagrams of which i thought I
didn't have
anymore. It contains some usefull info but probably much less than the
MK11 users guide.
BTW, the thumbwheel switches are all set to 0.

On the M8158, jumpers w1 & w3 are out, w2 and w4 are in. According to
the eng. diag.,
these bypass a small circuitry which would otherwise generate the ACLO &
presumably when the powerfail circuit has a problem?

As a side note, there are no battery packs in this config.
I have now set the system size register to all off, this then sets the
memory to 2048MW. From an archive article I read it says that this
can have an higher setting that there is actual memory in the box, but
that the
system will only address up to the actual available limit (which makes

Odd enough, when I changed the SSR, the memory starts now at 1400000 and
through 1477777, very odd.

Tomorrow I'll step through all the entries listed in your last mail, it
may very
well be the case that the address and/or data buffer of the memory box
are faulty,
in which case I have to get a new one.


Pete Turnbull wrote:
> On Jan 8, 10:44, The Wanderer wrote:
> > Pete Turnbull wrote:
> > >
> > > OK. From what you've written there, and a few other places, I assume
> you
> > > have some manuals and/or printsets?
> >
> > Most of them, but from the MK11 memory box, only the MOS board and both
> > controller boards.
> That's a pity, bacause he manual for the MK11 system has a lot of
> troubleshooting flow charts -- too much for me to try to reproduce. And
> it has the setup instructions, of course.
> > > > > That's an unusual address, and it's only 32K bytes (16KW). You said
> > > you
> > > > > had two 64KW boards. What type are they? They probably have
> switches
> > > Are they M8728-AA or M8728-CA? The latter is only 16KW. The easy way to
> > > tell the difference, if there's no -A or -C beside the number, is that
> >
> > One is a '-AA' version, the other is a '-AC' one, and both are fully
> > populated.
> >From reading the manual, it looks like two arrays (M8728) is the minimum
> for the box. It might work with one, though.
> > There are no switches at the front of the box, unless you mean the
> > control panel
> > which contains the thumbwheel switches and a few other switches?
> Yes, that's what I meant. The three thumbwheel switches on the left set
> the start address of the box, in 32KW blocks. That's the smallest size you
> can have in a box, and since the arrays are either 16KW or 64KW I think you
> need to have at least two (but you can have an odd number, eg 3, after that
> -- it just won't do any interleaving). Anyway, set these three to zero.
> The other thumbwheel (?) switch sets the external interleave; it has to be
> set to zero unless you are interleaving between multiple boxes.
> Then the cards have to be in the correct slots. Looking from the front,
> slot 1 is on the right, and slot 26 is on the left, PSU regulators are at
> the back.
> The address buffer (M8158) must be in slot 13, the data buffer (M8159) in
> slot 15. The #0 Control A board (M8160) must be in slot 11 and the #1
> Control A board in slot 16. The #0 Control B board (M8161) must be in slot
> 10 and the #1 Control A board in slot 17. The #0 controllers handle the
> even-numbered arrays, in slots 2...9; the #1 controllers handle the
> odd-numbered arrays, in slots 18...25. Slots 1,12,14,26 are not used.
> You must set the power-fail jumpers on the M8158. The manual says W1 out,
> W2 in; W3 out, W4 in. I'm not sure if that's always true. I don't know
> what you do if you don't want the battery backup!
> You must also put terminators on the outgoing connectors on the address and
> data buffers of the last box (the only box, in your case). These are H873
> terminator packs, four altogether, one for each BC06R cable. The incoming
> cables go on J1 and J3 (nearest the long edge of the board), and the
> terminators go on J2 and J4. You MUST put the screws in the terminators,
> as that's how they get the power.
> The first array, #0, must go in slot 9, and the next, #1, in slot 18. Then
> work out from the centre if you ever add more. There must not be any gaps.
> If there are some 16K boards and some 64K boards, the 16K boards must all
> be before the 64K ones.
> > Do you have documentation on the data buffer board? This one does have 2
> > switchbanks, and all are currently 'open'. Those 2 boards are the
> > only one for which I do not have any docs.
> I didn't see anything about switches on the data buffer. The address
> buffer is described as having three switches to set the CSR address of the
> box. For the first box, set address 17777100 by setting S1, S2, and S3 all
> closed. For the next box, open S1. For the third, open S2, close S1. And
> so on. Ech box uses two words for the CSR.
> > > It looks as though the box might be set to the wrong address -- 400000
> > > is
> > > 131072 decimal, or 128K -- and is only showing 16KW (32KB) of memory. I
> > > don't know how you set the address of the box, though.
> >
> > I changed the size register on the 8143 to 32K, and it 'disappeared'
> > completely
> > from the system, i.e. no memory address was usable.
> The MK11 logic checks the address on the bus to make sure it's between the
> limits set by the size register in the CPU, and it's start address. If the
> address on the bus is less than the box's start address, or higher than the
> size register, it will not respond.
> > > Why do you think address 777644 is the diagnostics ROM start address?
> >
> > That was a mistake, I did mean 765744, which is spoken about in the
> > documentation.
> That's not an entry point! It's not even executable code, it's the ROM
> Identification word. It contains the ASCII characters "B0" to identify the
> ROM. The only entry points are:
> 773x04 to boot without diagnostics
> 773x06 to boot with diagnostics
> aaaaaa address dependant on the bootstrap ROM version, which jumps
> to 765564 in the diagnostic ROM
> 765564 JMP to start of diagnostics
> 765000 start of disgnostic code
> Obviously there are other points at which you could enter the diagnostics,
> but you'd need to set some things in memory and registers first.
> BTW, I discovered you can disable the cache by setting 000014 in the status
> register at 17777746. If the cache is faulty, but enabled, the memory box
> won't work properly, apparently. I don;t think that's your problem,
> though. More like a start address error.
> The first part of the troubleshooting flowchar starts by saying that you
> want to boot XXDP and run the MK112 diagnostic program :-) Well, obviously
> you can't do that, but it does say that if you can't boot, then first check
> ALL the power supplies (sound advice anyway).
> The next part of the flowchart goes like this:
> 1) Can you boot XXDP?
> If "no", is the memory box ON LINE?
> If "no", put it ON LINE and go back to (1)
> If "yes", is MEM PWR READY lit?
> If "no", "ZAP 200" [I have no idea what this means!]
> If "yes", suspect (in this order):
> BA11K regulator
> 7014251 battery backup regulator
> 11/70 Unibus problem
> If "no",
> reverse or replace the grey box control cable
> If "yes", is "UNCORR ERROR"?
> If "yes", go to next sheet [which is too complex to type]
> If "no", is there an "ADDR ERROR"?
> If "yes", suspect (in order):
> bad or loose BC06R cable
> address interface, M8158
> 11/70 cache fault
> If "no", halt CPU
> power memory box off
> power memory box on again
> Is there "CONFIG ERROR"?
> If "yes",
> install arrays properly
> suspect Control A (M8160) on right side
> If "no", is "SELECT PANEL" lit?
> If "yes", go to next sheet
> If "no", set "FORCE FRONT PANEL"
> Is it lit?
> If "no", suspect (in order):
> "Reset Box" control cable
> switch or light on box controller
> data buffer, M8159
> If "yes", suspect (in order):
> data buffer, M8159
> address buffer, M8158
> Maybe this will be of some help.
> > > All the 11/70 tests halt on error
> [...]
> > > So having it loop until you stop it, and then halt at some address
> > > ending
> > > in 344 doesn't make much sense to me.
> I wonder if it was trying to store data in 000700...000706 (which it does
> at the very start of the diagnostics), getting a bus error (no memory),
> trying to access the trap vector at the bottom of memory, getting a bus
> error for that too, and just getting stuck until you halted it.
> --
> Pete Peter Turnbull
> Network Manager
> University of York

The Wanderer                      | Politici zijn gore oplichters.                  | Europarlementariers: zakkenvullers      | en neuspeuteraars.
Unix Lives! M$ Windows is rommel! | Kilometerheffing : De overheid
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Received on Wed Jan 09 2002 - 15:42:57 GMT

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