Tornado Computer Unit - Any info around?

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Erik Baigar

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Jan 11, 2005, 1:23:39 PM1/11/05
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Dear avionics and tornado enthusiasts,

Recently I came across an part of computer
equipment originating from a tornado aircraft.
The original avionics equipment of these aircraft
has been replaced by a more up to date one according
to several internet sites.

The item looks like a complete computer with
the size of a shoebox and contains core memory,
processor boards and interface boards as well as
some kind of power supply.

Since this was high tech in the 70ies and it should
be preserved as well as all information available.
Thus I'd highly be interested in learning more about
this unit (maybe it can be brought up to play a
ported version of the PDP8 chess game chekmo?)!

Therefore I describe what I know up to date and
perhaps someone has more info for me which can
be useful in any manner...

The label reads "Programmer electronic Control", manufactured
by Marconi Avionics with part number 51-019-02, NSN1680-99-652-3410.
There are lots of boards in it. Among them are boards dealing with
driving the core memory:

(1) Driver Board, 1680-99-646-6754 and
(2) Data Board, 1680-99-646-6755.

The core memory itself consists of a sandwich of two boards
by GEC-Computers. The capacity must be around 64k Bits:
(3) Core Memory, 5841-99-652-3386.

There is another driver board identical to (1):
(4) Driver Board, 1680-99-646-6754 followed by an
(5) Control Board, 1680-99-646-6753.

Next there follow boards which seem to be a kind of processor
(6) Data Register, 229-013909 and a second
(7) Data Register, 229-013909
(8) Control Register, 229-013551
The following board contains some kind of ROM (MMI5330-IJ) which
I suppose contain the micro-code, i.e. represent the machine
language of the device (concluding from pinput the ROMs maybe
512*4 or lower capacity):
(9) Function Decode, 229-013549

The next board contains several monoflops but if it is connected
to 5V (which seems to be its only supply) it drwas approx. 0.7A
but does not generate any signals. This board seems to generate
various timings but NOT the master clock:
(10) Processor Timing, 229-013547

Than there follows a group of boards, obviously dealing
with IO:
(11) RxTx Interface, 229-013545
(12) Serial Parallel Converter, 229-016304
(13) Decode and Interrupt, 229-013905

The last board is the only board to contain a crystal
running at 8MHz and several monofolps as well. Powered
(by obviuosly a single 5V supply, consuming 1.05A) this
board distrubutes some signals to the mainboard.

The most interesting things would be a schematic (of
course!) and a instruction set - any ideas?? Of course
reverse engineering would be possible, but it would
be extremely difficult: Multilayer boards, lots of 74xx
chips, everyting glued and protected by acryl coating...
So any hints (supply voltages, pinouts of the connectors)
are welcome...

Best regards,

Erik.

Simon Robbins

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Jan 11, 2005, 5:50:58 PM1/11/05
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"Erik Baigar" <er...@baigar.de> wrote in message
news:41E419AB...@baigar.de...

> Since this was high tech in the 70ies and it should
> be preserved as well as all information available.
> Thus I'd highly be interested in learning more about
> this unit (maybe it can be brought up to play a
> ported version of the PDP8 chess game chekmo?)!

I don't know what the box is but I wouldn't expect it to still be in working
order. Onboard systems get a real beating and it's line-replacable cards go
unservicable all the time. If you can identify the interfaces you might
get lucky in trying to figure out what it connects to, but without detailed
interface specs you'll never be able to drive it, and those may well be
proprietary information, and protected to this day. (Of course, knowing the
RAF, it might well be servicable and still fitted to half the Tornado
fleet...)

You could always try and sell it on ebayski!!

Si


Alan Dicey

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Jan 11, 2005, 6:53:13 PM1/11/05
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Erik Baigar wrote:
> Dear avionics and tornado enthusiasts,
>
> Recently I came across an part of computer
> equipment originating from a tornado aircraft.
> The original avionics equipment of these aircraft
> has been replaced by a more up to date one according
> to several internet sites.
>
> The item looks like a complete computer with
> the size of a shoebox and contains core memory,
> processor boards and interface boards as well as
> some kind of power supply.
>
> Since this was high tech in the 70ies and it should
> be preserved as well as all information available.
> Thus I'd highly be interested in learning more about
> this unit (maybe it can be brought up to play a
> ported version of the PDP8 chess game chekmo?)!
>
> Therefore I describe what I know up to date and
> perhaps someone has more info for me which can
> be useful in any manner...
>
> The label reads "Programmer electronic Control", manufactured
> by Marconi Avionics with part number 51-019-02, NSN1680-99-652-3410.
> There are lots of boards in it. Among them are boards dealing with
> driving the core memory:

This is a dedicated avionics box, from the FCS, and is perhaps
comparable to a modern automobile ECU; not in any way a general purpose
computer. Off the top of my head, the processor will be a proprietary
Marconi bit-slice machine. It is very specifically designed for
real-time safety-critical processing, taking inputs from the flight
controls and airframe sensors and providing outputs to the control
surfaces. Not even an RS-232 interface, no display functions. I think
the chances of making any use of it are very slim indeed, and it is most
likely that the insides are fried anyway. Where on earth did you get it
from?

> The most interesting things would be a schematic (of
> course!) and a instruction set - any ideas?? Of course
> reverse engineering would be possible, but it would
> be extremely difficult: Multilayer boards, lots of 74xx
> chips, everyting glued and protected by acryl coating...
> So any hints (supply voltages, pinouts of the connectors)
> are welcome...

I don't know for sure, but I suspect that such things will still be
classified. Good luck. Let us know if you find anything...

Erik Baigar

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Jan 12, 2005, 3:27:51 PM1/12/05
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Simon Robbins wrote:
>
> "Erik Baigar" <er...@baigar.de> wrote in message
> news:41E419AB...@baigar.de...
> > Since this was high tech in the 70ies and it should
> > be preserved as well as all information available.
> > Thus I'd highly be interested in learning more about
> > this unit (maybe it can be brought up to play a
> > ported version of the PDP8 chess game chekmo?)!
>
> I don't know what the box is but I wouldn't expect it to still be in working
> order.
OK, maybe. The case shows some tear and wear. On the other hand
the components have all been very common 20 years ago and you
could find them all in discarded electronics.

> interface specs you'll never be able to drive it, and those may well be
> proprietary information, and protected to this day. (Of course, knowing the

You are absolutely right. Since the unit seems to be rather old and
the technology used, was obsolete 10 years ago, my hope is that some
information is already around. But if it is still classified, the
best would be not to waste any time and put the box apart and throw
it away...

> You could always try and sell it on ebayski!!

It's from there, but from .uk, not .ski ;-)

Thanks anyway,

Erik.

Erik Baigar

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Jan 12, 2005, 3:45:05 PM1/12/05
to
Alan Dicey wrote:
> This is a dedicated avionics box, from the FCS, and is perhaps
> comparable to a modern automobile ECU; not in any way a general purpose
> computer.
OK, you mean some hard wired and optimized failsafe operations.

> surfaces. Not even an RS-232 interface, no display functions. I think

I did not expect a monitor interface and a linux port but maybe some
proprietary serial connection and boot process (I doubt that someone
would store vital software in core memory linke in ROMs).

> the chances of making any use of it are very slim indeed, and it is most
> likely that the insides are fried anyway.

I agree, that the chance of geting a unit one does not know anything
about and which is likely defective, back to do someting useful is very
small!

> Where on earth did you get it
> from?

Since one of my hobbies is to restore old computer hardware,
I regularly screen eBay for "core memory" and there I came
across these units. A company in the UK sold some of them
and they where rather cheap (compared to a PDP8 or someting
like this). Look at e.g. at item no. 2282449528 - there you
will find some photos, too. This company (abex) seems to sell
military surplus from time to time. Look at at their site
http://www.abex.co.uk/sales/sales.html for their sales page
and at http://www.abex.co.uk/sales/electronic/other/other.htm
for the military items.

> > be extremely difficult: Multilayer boards, lots of 74xx
> > chips, everyting glued and protected by acryl coating...
> > So any hints (supply voltages, pinouts of the connectors)
> > are welcome...
> I don't know for sure, but I suspect that such things will still be
> classified. Good luck. Let us know if you find anything...

Apart two answers no info up to date, but thanks a lot for
your explanations.

John Cook

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Jan 12, 2005, 5:05:56 PM1/12/05
to
You could always keep it till one of the tornados comes up on Ebay,
then you'd have the complete set??.

Details of this of equipment tend to escape rather than be released,
someone who used to maintaine them may be of help, try
WWW.PPrune.org

Its stuffed full of people who know whats what!, and they could a
least tell you if its a bit erm!!! - 'sensitive' or not.

Cheers
John Cook

Any spelling mistakes/grammatic errors are there purely to annoy. All
opinions are mine, not TAFE's however much they beg me for them.

Email Address :- Jwcook@(trousers)ozemail.com.au
Spam trap - please remove (trousers) to email me
Eurofighter Website :- http://www.eurofighter-typhoon.co.uk

Simon Robbins

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Jan 12, 2005, 7:28:56 PM1/12/05
to
"Erik Baigar" <er...@baigar.de> wrote in message
news:41E58C51...@baigar.de...

> I did not expect a monitor interface and a linux port but maybe some
> proprietary serial connection and boot process (I doubt that someone
> would store vital software in core memory linke in ROMs).

Actually it almost certainly is on PROM. The only stuff that's normally
loaded into volatile memory is mission specific files and any additional
data that is of a classified nature. There'll be a procedure for trashing
any such data upon enemy interception, forced landing on unfriendly soil,
etc. But from what someone else said, it doesn't sound like a mission
computer so probably doesn't have that kind of feature.

Si


Benjamin Gawert

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Jan 13, 2005, 1:02:31 AM1/13/05
to
Erik Baigar wrote:

> Recently I came across an part of computer
> equipment originating from a tornado aircraft.
> The original avionics equipment of these aircraft
> has been replaced by a more up to date one according
> to several internet sites.
>
> The item looks like a complete computer with
> the size of a shoebox and contains core memory,
> processor boards and interface boards as well as
> some kind of power supply.
>
> Since this was high tech in the 70ies and it should
> be preserved as well as all information available.
> Thus I'd highly be interested in learning more about
> this unit (maybe it can be brought up to play a
> ported version of the PDP8 chess game chekmo?)!
>
> Therefore I describe what I know up to date and
> perhaps someone has more info for me which can
> be useful in any manner...
>
> The label reads "Programmer electronic Control", manufactured
> by Marconi Avionics with part number 51-019-02, NSN1680-99-652-3410.

If I remember right this LRU is part of the Flight Control System
(Autopilot). It was interfaced to the Control and Stability Augmentation
System (CSAS) Control Unit.

It's probably from one of the EOL'd GR.1 that the UK did salvage. The FCS
however isn't really a confidential part, so it's imagineable that these
parts somehow might find hands on ebay from time to time.

> The most interesting things would be a schematic (of
> course!) and a instruction set - any ideas??

Forget it! These is not Your average old computer. It's a very specialized
device with limited capability. The processors aren't freely programmable
like the ones in general purpose computers. The interfaces are MIL-STD 1553B
with proprietary data word formats, barely suitable for anything You can do
with it...

Benjamin

--
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
Q: What is the most annoying thing on usenet and in e-mail?

Alan Dicey

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Jan 13, 2005, 5:15:36 PM1/13/05
to
Erik Baigar wrote:

> Alan Dicey wrote:
>
>>This is a dedicated avionics box, from the FCS, and is perhaps
>>comparable to a modern automobile ECU; not in any way a general purpose
>>computer.
>
> OK, you mean some hard wired and optimized failsafe operations.
>

Not really. If, as I think, it is part of the FCS, it has no
general-purpose i/o, everything is dedicated. Inputs will be tailored
for the stick, pedal and throttle position sensors, pitot-static inputs,
etc. Outputs will expect to drive control surface actuators.

> I did not expect a monitor interface and a linux port but maybe some
> proprietary serial connection and boot process (I doubt that someone
> would store vital software in core memory linke in ROMs).

No serial interface: nothing will need it. This is a real-time system,
where dedicated, predictable, repeatable response times are paramount.

Someone upthread mentioned MIL-STD-1553: Tornado (if this was a Tornado
box) does use the 1553 bus, but not for the FCS. Too slow and
upredictable...

You do know that ferrite core memory is non-volatile, don't you?
However, there will have been a PROM with the clever bits in it somewhere.

No boot process. Nothing to boot. No OS.

>
> I agree, that the chance of geting a unit one does not know anything
> about and which is likely defective, back to do someting useful is very
> small!
>

About the only thing you could hope to use this box for is as part of a
Tornado simulator. And for that you'd need the control law maps, which
will not have been in the box, being MAv (and thus now BAE SYSTEMS)
proprietary.

>
>>Where on earth did you get it
>>from?
>
> Since one of my hobbies is to restore old computer hardware,
> I regularly screen eBay for "core memory" and there I came
> across these units. A company in the UK sold some of them
> and they where rather cheap (compared to a PDP8 or someting
> like this). Look at e.g. at item no. 2282449528 - there you
> will find some photos, too. This company (abex) seems to sell
> military surplus from time to time. Look at at their site
> http://www.abex.co.uk/sales/sales.html for their sales page
> and at http://www.abex.co.uk/sales/electronic/other/other.htm
> for the military items.
>

Interesting site. I have never seen an avionics black box described as
a work of art before. Makes me think that they want entirely too much
money for it...

Erik Baigar

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Jan 14, 2005, 11:49:24 AM1/14/05
to
Benjamin Gawert wrote:
> > The most interesting things would be a schematic (of
> > course!) and a instruction set - any ideas??
> Forget it! These is not Your average old computer. It's a very specialized
> device with limited capability. The processors aren't freely programmable
> like the ones in general purpose computers. The interfaces are MIL-STD 1553B
> with proprietary data word formats,
google-ing for 1553B one finds lots of documents describing the basics
and the implementation of this standard, but this more advanced than
this
box. The box with its hundreds of pins in the connectors (see pics on
the
abex homepage mentioned in another posting) looks different - as Alan
Dicey
already mentioned.

Erik Baigar

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Jan 14, 2005, 12:04:55 PM1/14/05
to
> You do know that ferrite core memory is non-volatile, don't you?
Of course I know. 96kBit as stated on the abex site are
quite a big amount of memory for those days. And compared
to the ROMS (DIL14, i.e. max 2kBits per chip) its huge.

> However, there will have been a PROM with the clever bits in it somewhere.

Maybe another box.

> About the only thing you could hope to use this box for is as part of a
> Tornado simulator. And for that you'd need the control law maps, which
> will not have been in the box, being MAv (and thus now BAE SYSTEMS)
> proprietary.

Since I do not know anything about this aircraft or avionics in general
this is no option. I think I'd best use the box for placing the nicest
looking part on my bookshelf and discarding the rest. ;-)

> > military surplus from time to time. Look at at their site
> > http://www.abex.co.uk/sales/sales.html for their sales page
> > and at http://www.abex.co.uk/sales/electronic/other/other.htm
> > for the military items.
> Interesting site. I have never seen an avionics black box described as
> a work of art before.

It is not directly art, but from an engineering point of view
it is nicely designed: Case milled out of a compact aluminium
body, cover has stuctures milled in, to make it more rigid.
Yes, I'd admit that the pictures at abex are nice to look at (the real
one has more damages). But on the other hand, e.g. it's missing
an electrical connection between the body and the cover - there is
a rubber seal inbetween. So I do not wonder why in Bavaria/Germany
Government had to declare the area around a strong broadcasting station
as a "do not fly in zone" after a military aircraft had trouble there...

> Makes me think that they want entirely too much

Compared to the prices one has to pay for a very common
core plane ripped from an IBM mainframe the 70pounds
are not so much. This was the main motivation for me to
bid.

Simon Robbins

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Jan 14, 2005, 7:34:39 PM1/14/05
to
"Alan Dicey" <al...@removethis.diceyhome.free-online.co.uk> wrote in message
news:41e6f327$0$91441$ed26...@ptn-nntp-reader03.plus.net...

> Interesting site. I have never seen an avionics black box described as
> a work of art before. Makes me think that they want entirely too much
> money for it...

I once spent an enjoyable hour throwing unserviceable old ruggedised ATR
boxes at a stack of old monitors that we'd lined up along the back wall of a
skip. Never occurred to us that we were committing artistic vandalism!
:^)

Si


Simon Robbins

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Jan 14, 2005, 7:43:20 PM1/14/05
to
"Erik Baigar" <er...@baigar.de> wrote in message
news:41E7F814...@baigar.de...

> google-ing for 1553B one finds lots of documents describing the basics
> and the implementation of this standard, but this more advanced than
> this
> box. The box with its hundreds of pins in the connectors (see pics on
> the
> abex homepage mentioned in another posting) looks different - as Alan
> Dicey
> already mentioned.

Mil-Std-1553B describes the protocols for message interaction, not the
content of the messages themselves which would be specific to the
application, and likely proprietary. Like knowing how TCP/IP works doesn't
give you any clue about the content or purpose of emails traversing it.

1553B is generally used for low-priority mission data, i.e. radar contacts,
nav data, etc. not real-time control.

I'm guessing your "hundreds of pins" are huge, round, screw-in things, no?
These are a standard fitting, but not a standard interface. The pin-outs
will be specific to the application, and only the wiring diagrams and
Interface Control Documents will shed any light on what pins do what. Many
large connectors of his type carry multiple pin-out sets for multiple
interfaces. The wiring will then branch off in different cables from the
wiring harness to seperate other boxes.

If I were you, I'd be tempted to strip the guts out of the box and try and
build myself a nice little PC inside it, using the mini-PC motherboards and
stuff available these days. Then custom build myself some cable adaptors to
use those obscure connectors. Heck it'd make a great embedded PC box in a
homebuilt sim cockpit!!

Si


John Cook

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Jan 14, 2005, 8:52:05 PM1/14/05
to

I was involved in the driving over 50 nearly new computers in a
bulldozer......including the monitors,hdd,cpu,ram, then individually
making sure the ram, hdd, and cpu's were destroyed.

I can understand Hdd and monitors, but cpu's and ram!!!.

Made me very very sad as they were 10 times better than my old clunker
at the time...

Cheers

>
>Si

Erik Baigar

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Jan 18, 2005, 2:14:39 PM1/18/05
to
Simon Robbins wrote:
> Mil-Std-1553B describes the protocols for message interaction, not the
> content of the messages themselves which would be specific to the
> application, and likely proprietary. Like knowing how TCP/IP works doesn't
> give you any clue about the content or purpose of emails traversing it.
OK, thats pretty clear.

> 1553B is generally used for low-priority mission data, i.e. radar contacts,
> nav data, etc. not real-time control.

Yep, I see - therefore not present in the mentioned Flight Control box
since
it is realtime.

> I'm guessing your "hundreds of pins" are huge, round, screw-in things, no?

Exactly.

> These are a standard fitting, but not a standard interface. The pin-outs
> will be specific to the application, and only the wiring diagrams and
> Interface Control Documents will shed any light on what pins do what. Many
> large connectors of his type carry multiple pin-out sets for multiple
> interfaces. The wiring will then branch off in different cables from the
> wiring harness to seperate other boxes.

Ah, I see - so there will be the same type of connector in many
of the boxes (if the one box is so highly specific there must be 10
or more boxes like this aboard such an aircraft?). And pinouts are
different since the right connections are done by the branches
of the cable tree. So plugging everything in the service personnel
has to pay attention not to interchange the plugs, right?



> If I were you, I'd be tempted to strip the guts out of the box and try and
> build myself a nice little PC inside it, using the mini-PC motherboards and
> stuff available these days. Then custom build myself some cable adaptors to
> use those obscure connectors. Heck it'd make a great embedded PC box in a
> homebuilt sim cockpit!!

Hey, that sounds a good idea. I think it will only be rather difficult
to get the right connectors fitting into the plugs after all I have
learned form the postings ;-)

Erik.

Erik Baigar

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Jan 18, 2005, 2:17:51 PM1/18/05
to
John Cook wrote:
>
> On Sat, 15 Jan 2005 00:34:39 -0000, "Simon Robbins"
> <si...@NOSPAMsjrobbins.demon.co.uk> wrote:
>
> >"Alan Dicey" <al...@removethis.diceyhome.free-online.co.uk> wrote in message
> >news:41e6f327$0$91441$ed26...@ptn-nntp-reader03.plus.net...
> >> Interesting site. I have never seen an avionics described as

> >> a work of art before. Makes me think that they want entirely too much
> >> money for it...
> >
> >I once spent an enjoyable hour throwing unserviceable old ruggedised ATR
> >boxes at a stack of old monitors that we'd lined up along the back wall of a
> >skip. Never occurred to us that we were committing artistic vandalism!
> >:^)
>
> I was involved in the driving over 50 nearly new computers in a
> bulldozer......including the monitors,hdd,cpu,ram, then individually
> making sure the ram, hdd, and cpu's were destroyed.
>
> I can understand Hdd and monitors, but cpu's and ram!!!.
>
> Made me very very sad as they were 10 times better than my old clunker
> at the time...
>
> Cheers
>
Yes, I joined such session, too: How far you guess a 14" monitor
can be thrown using a firmly connected VGA-cable. But the stuff
which was destroyed there was far much common and thus - in my
opinion - it was definitively not vandalism. But in the case of
such a black box . . . . . ;-)

Simon Robbins

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Jan 18, 2005, 3:17:58 PM1/18/05
to

"Erik Baigar" <er...@baigar.de> wrote in message
news:41ED601F...@baigar.de...

> Ah, I see - so there will be the same type of connector in many
> of the boxes (if the one box is so highly specific there must be 10
> or more boxes like this aboard such an aircraft?). And pinouts are
> different since the right connections are done by the branches
> of the cable tree. So plugging everything in the service personnel
> has to pay attention not to interchange the plugs, right?

There could well be many similar connectors on multiple boxes but typically
the boxes will use connectors where the locating lugs on the outside of the
screw housing will be in different places, so even though several connectors
are the same size and number of pins, you can't screw the wrong one in.
You'll likely have numerics next to each connector socket, which will match
labels on the plugs on the loom. At least that's my experience of those
mil-spec connectors anyway. I don't know specifically about the box you
have, but most aircraft wll have several of those ATR/half ATR form-factor
boxes doing specific and different tasks, some may also be duplicate for
dual-redundancy in case of failure.

Si


Benjamin Gawert

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Jan 19, 2005, 9:18:10 AM1/19/05
to
Erik Baigar wrote:

> google-ing for 1553B one finds lots of documents describing the basics
> and the implementation of this standard, but this more advanced than
> this
> box. The box with its hundreds of pins in the connectors (see pics on
> the
> abex homepage mentioned in another posting) looks different - as Alan
> Dicey
> already mentioned.

I'm working with several avionics black boxes that contain "hundred of
pins". The No. of pins says nothing about the interface type...

The Tornado FCS is connected to the main computer over one of the IFUs
(Interface Units) using a 1553B (which btw. is also suitable for real-time
tasks like for FCS, but not used in the PA200 for the purpose of
transmitting control inputs)...

Alan Dicey

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Jan 19, 2005, 9:45:36 AM1/19/05
to
Erik Baigar wrote:

> Dear avionics and tornado enthusiasts,
>
> Recently I came across an part of computer
> equipment originating from a tornado aircraft.
> The original avionics equipment of these aircraft
> has been replaced by a more up to date one according
> to several internet sites.

snip

>
> The label reads "Programmer electronic Control", manufactured
> by Marconi Avionics with part number 51-019-02, NSN1680-99-652-3410.
> There are lots of boards in it. Among them are boards dealing with
> driving the core memory:
>

If as you suspect this was part if a Tornado Flight Control System, I'd
be looking for names like CSAS, SPILS, AFDS, ADC, whch are the
designations of the principal parts of the system. One other possiblity
is that it is part of the SMS (Stores Management System). I can't
decode the part numbers.

Erik Baigar

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Jan 25, 2005, 1:44:19 AM1/25/05
to
John Cook wrote:
> Details of this of equipment tend to escape rather than be released,
> someone who used to maintaine them may be of help, try
> WWW.PPrune.org
In the meantime I placed a posting there. After 24 hours of
beeing online there have been around 80 views but no reply yet.

By the way, this Rumor Network is a very interesting forum
where one can learn a lot if interesting things and where a
lot of highly actual information around aircraft and related
topics are available - Thanks for this hint!

Erik Baigar

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Jan 25, 2005, 12:51:27 PM1/25/05
to
Erik Baigar wrote:
>
> John Cook wrote:
> > Details of this of equipment tend to escape rather than be released,
> > someone who used to maintaine them may be of help, try
> > WWW.PPrune.org
> In the meantime I placed a posting there. After 24 hours of
> beeing online there have been around 80 views but no reply yet.

Took some pictures of the Programmer Electronic Control box
ant put them onto my homepage, since I was not allowed to
place a Link in my posting on PPruNe, see
http://www.baigar.de/TornadoComputerUnit/

John Cook

unread,
Jan 25, 2005, 4:21:14 PM1/25/05
to
On Tue, 25 Jan 2005 20:43:11 +0000 (UTC), Pat Carpenter
<patandch...@btinternet.com> wrote:

>Have you tried contacting Marconi Avionics in Rochester UK as they
>were probably the makers.
>
>
>http://www.enhanceproject.com/Presentation/partners-presentation/gecavionics.pdf#search='Marconi%20Avionics%20rochester'
>
>I remember visiting the test division there and see various units
>being tested in environmental chambers. They were testing to +100K
>feet and -200 feet, When questioned about the viability of the limits
>they said the plus value was in case it got that high with a AAM up
>it's "arse" and the minus in case the Israelis brought some and based
>them in under ground hangers by the Dead Sea!
>Blue Skies
>Pat Carpenter

I was at the college opposite, when two Tornado's did a Very low
flypast as a thank you!!, rattle every window in the building, and
scared us all to death as we were not expecting it!!

The return flypast was much better as we were ready for it...

Cheers

Pat Carpenter

unread,
Jan 25, 2005, 3:43:11 PM1/25/05
to
On Wed, 19 Jan 2005 14:45:36 +0000, Alan Dicey
<al...@removethis.diceyhome.free-online.co.uk> wrote:

Have you tried contacting Marconi Avionics in Rochester UK as they

Alan Dicey

unread,
Jan 25, 2005, 7:01:07 PM1/25/05
to
Pat Carpenter wrote:

>
> Have you tried contacting Marconi Avionics in Rochester UK as they
> were probably the makers.
>
>
> http://www.enhanceproject.com/Presentation/partners-presentation/gecavionics.pdf#search='Marconi%20Avionics%20rochester'
>
> I remember visiting the test division there and see various units
> being tested in environmental chambers. They were testing to +100K
> feet and -200 feet, When questioned about the viability of the limits
> they said the plus value was in case it got that high with a AAM up
> it's "arse" and the minus in case the Israelis brought some and based
> them in under ground hangers by the Dead Sea!

It hasn't been Marconi Avionics for a long time now. When I joined it
it was MEASLs (Marconi-Elliott Avionic Systems Limited), which then
became Marconi Avionics, then GEC Avionics. About five or six years ago
the Defence bits of GEC were bought by British Aerospace, the whole
becoming BAE Systems. The other bits of Marconi tried to make a killing
in networking and came ustuck in a big way.

So what was Marconi Avionics is now BAE Systems. The Rochester factory
is still there and still in the avionics business. It makes the
Eurofighter Typhoon FCS. If all else fails I'll go and see if I can
find any of the project staff left over from Tornado days - they might
recognise this box.

Erik Baigar

unread,
Jan 26, 2005, 2:36:31 AM1/26/05
to
Alan Dicey wrote:
> So what was Marconi Avionics is now BAE Systems. The Rochester factory
> is still there and still in the avionics business. It makes the
> Eurofighter Typhoon FCS. If all else fails I'll go and see if I can
> find any of the project staff left over from Tornado days - they might
> recognise this box.
Hey, that sounds great. Somewhere in this thread the possibility was
mentioned that the box might be classified even today. But in the
meantime
I know for sure that it is not mentioned in BAE's electronic databases
in
the tornado context. I am not very astonished about this since it must
be
around 25 years old and has serial number 42. It must originate from a
very early version and is not used today...
But if I imagine beeing asked in 2030 about things I have done today
I do not know how much I will be able to remember than... ;-)

Harry Andreas

unread,
Jan 26, 2005, 11:32:56 AM1/26/05
to
In article <41F7487F...@baigar.de>, Erik Baigar <er...@baigar.de> wrote:

> Alan Dicey wrote:
> > So what was Marconi Avionics is now BAE Systems. The Rochester factory
> > is still there and still in the avionics business. It makes the
> > Eurofighter Typhoon FCS. If all else fails I'll go and see if I can
> > find any of the project staff left over from Tornado days - they might
> > recognise this box.
> Hey, that sounds great. Somewhere in this thread the possibility was
> mentioned that the box might be classified even today.

If the unit was classified it would be marked as such on the front
panel of the unit.


> But in the meantime
> I know for sure that it is not mentioned in BAE's electronic databases
> in
> the tornado context. I am not very astonished about this since it must
> be
> around 25 years old and has serial number 42. It must originate from a
> very early version and is not used today...
> But if I imagine beeing asked in 2030 about things I have done today
> I do not know how much I will be able to remember than... ;-)

I worked on the pre-production units of the APG-65 radar for the
flight test F/A-18 aircraft back in 1978. I could recognize them in an
instant even today.

If he takes it to BAE the real question is whether there is still anyone
there who worked on it. With the aerospace industry turnover of
the last 25 years it's probable that everyone is at other jobs now.

--
Harry Andreas
Engineering raconteur

Erik Baigar

unread,
Jan 30, 2005, 1:35:59 PM1/30/05
to
Harry Andreas wrote:
> > > find any of the project staff left over from Tornado days - they might
> > > recognise this box.
> > Hey, that sounds great. Somewhere in this thread the possibility was
> > mentioned that the box might be classified even today.
> If the unit was classified it would be marked as such on the front
> panel of the unit.
There is no label on my box stating that it could be classified. On
the pictures on Abex's web site there is no such label visible, too.
But obviuosly not beeing classified does not mean that information
is readily availablee :-(

> > very early version and is not used today...
> > But if I imagine beeing asked in 2030 about things I have done today
> > I do not know how much I will be able to remember than... ;-)
> I worked on the pre-production units of the APG-65 radar for the
> flight test F/A-18 aircraft back in 1978. I could recognize them in an
> instant even today.

Indeed it seems to be the last possibility that someone might
remember what this box was good for...

Alan Dicey

unread,
Feb 15, 2005, 6:17:41 PM2/15/05
to


No positive identification yet. As far as can be told, from the guys
who remember that far back, this unit is not part of the FCS or the SMS.
The consensus is that it is most likely associated with the TV-Tab
displays in the rear cockpit, possibly to take the input from the
keyboard that surrounds the display and perform the switcing necessary
to route the correct display to the TV-Tab monitor.

Erik Baigar

unread,
Feb 16, 2005, 1:21:53 PM2/16/05
to
Alan Dicey wrote:
> No positive identification yet. As far as can be told, from the guys
Hey Alan, thanks a lot for your interest in this little box
and for your help!!

> who remember that far back, this unit is not part of the FCS or the SMS.

I am impressed that you really found someone of those days still
beeing there.

> The consensus is that it is most likely associated with the TV-Tab
> displays in the rear cockpit, possibly to take the input from the
> keyboard that surrounds the display and perform the switcing necessary
> to route the correct display to the TV-Tab monitor.

OK, I see. Maybe I will have a closer look to the boards in order
to get a idea what it was good for. I am sure at the moment that it
does not contain any analog circuitry (apart from some kind of
internal power supply which seems to generate the voltages needed
for core memory and so on) like analog switches, amplifiers,
transformers (as often used according to the web links regarding
the MIL1533 standard). All logic is TTL and nearly all chips are
well known 54xx types.
The circuitry around the core memory looks somehow different (other
material of the boards, different style in numbering) as the rest
of the box. Maybe this is because the boardset was used in other
boxes, too?
During january (when there was most activity in this thread)
I powered up one board taken out of the box: In there is a
clock generator (crystal) and powered up the board generates
some signals which are sent to the backplane. They look like
the phase shifted clock signals often used in computers of
those days (Phi1, Phi2). Interestingly the timing is generated
by monostable gates which can be adjusted.
If it is true, that the PROMS on one of the boards (indeed these
are the only non well known chips) contain the operating program
as you stated in an earlier posting than I'd expect that there
will be activity (e.g. accesses to the core memory) within the
box if I'd power up the complete box. Of course I know: if
something is severely dead it will keep quiet. Since I am really
curious about this box I will hopefully find the time to put the
parts together again and give it a try...
BTW power is supplied to the box by a 6-pin plug called DPL06.
Any idea what voltages are usually used aboard an aircraft? -
Just to give, I will have to examine the internal supply anyway.

I will keep you up to date and all hints are highly welcome!

Thanks again for the time you spent on this curiosity,

Erik.

Erik Baigar

unread,
Feb 17, 2005, 1:56:29 AM2/17/05
to
Alan Dicey wrote:
> who remember that far back, this unit is not part of the FCS or the SMS.
> The consensus is that it is most likely associated with the TV-Tab
> displays in the rear cockpit, possibly to take the input from the
> keyboard that surrounds the display and perform the switcing necessary
> to route the correct display to the TV-Tab monitor.
Thanks Alan! Last evening I did some detective work and found a
hint strongly supporting this theory: I carefully investigated
the layars of quality-assurance-stickers. Of course they are broken
and parts are lost but I was able to reconstruct them: Sticker applied
first reads "Marconi Avionics - Airborne Display Division - Rochester
Kent England". The sticker which was placed above the first one (maybe
during service or repair) reads "GEC Avionics - Airborne Display
Division
- Rochester Kent England"!!!

During investigating the internal power supply it became
evident that this unit has been changed at least once (severe
traces on the bolts holding the unit in place). The supply contains
a switch mode power supply made of OpAmps (747), comparators (LM111),
two gates, a flip flop and lots of discrete components. But the output
seems to be not more than four different voltages with one of them
beeing +5V (adjustable) and a lot of power for all the TTL chips.

There are two different types of connectors to the outer world.
Cables originating in connectors DPL01 to DPL06 unite to one
plug within the box (maybe they connect to the units delivering
information to be displayed). From there the cables go to the
backplane. The cables from DPL07 (beeing the plug with the most pins)
directly head to the backplane - they connect to the display unit I
suppose. Nearly all connections to the rest of the world seem
to end at boards 11, 12 and 13 (see my first posting). Only two
spread to the internal logic/memory and dataregister (maybe some
kind of reset).

I think displays of the 70ties where not raster displays like
todays, but they where vector displays (like analog oscilloscopes)
with the electron beam writing texts and lines directly?? Thus
the memory of the box may be some kind of graphics memory holding
the appropriate information which is than sent to the display.
The neccessary DACs for this seem to be outside of the box??!?

Alan Dicey

unread,
Feb 17, 2005, 9:45:17 AM2/17/05
to
Erik Baigar wrote:

> I carefully investigated
> the layars of quality-assurance-stickers. Of course they are broken
> and parts are lost but I was able to reconstruct them: Sticker applied
> first reads "Marconi Avionics - Airborne Display Division - Rochester
> Kent England". The sticker which was placed above the first one (maybe
> during service or repair) reads "GEC Avionics - Airborne Display
> Division
> - Rochester Kent England"!!!

As I said earlier, Marconi Avionics was renamed to GEC Avionics. It is
possible that the unit has been back to Rochester for servicing at some
stage


>
> During investigating the internal power supply

-----


> But the output
> seems to be not more than four different voltages with one of them
> beeing +5V (adjustable) and a lot of power for all the TTL chips.
>

I'll take your word for it. :-) Power supplies are a black art. I
guess the ferrite core memory needs different voltages from the TTL.


> I think displays of the 70ties where not raster displays like
> todays, but they where vector displays (like analog oscilloscopes)
> with the electron beam writing texts and lines directly?? Thus
> the memory of the box may be some kind of graphics memory holding
> the appropriate information which is than sent to the display.
> The neccessary DACs for this seem to be outside of the box??!?

Thats a very big question. VDU computer terminals were first introduced
in the '70's, and initially consisted of a "glass teletype" - displaying
25 lines x 80 characters or so of alphamerics. They were raster
displays, derived from TV technology. There were a few graphic displays
(Tektronix being the manufacturer I associate with them) that were
vector-driven.

All the extant pictures of the TV-Tabs show alphamerics and lineart
graphics, but that doesn't mean that the displays were vector-driven.

The display driver hardware is likely to be in the TV-Tab unit itself.

Harry Andreas

unread,
Feb 17, 2005, 11:13:43 AM2/17/05
to
In article <42138F41...@baigar.de>, Erik Baigar <er...@baigar.de> wrote:


> BTW power is supplied to the box by a 6-pin plug called DPL06.
> Any idea what voltages are usually used aboard an aircraft? -
> Just to give, I will have to examine the internal supply anyway.

Eric,
typical aircraft voltage is 115V, 3Phase, 400Hz and 28 Vdc.
I have never seen an aircraft of that vintage supply anything else.

Internally, the power supply probably converts to 270Vdc then
steps it down to +5Vdc, -5.2Vdc, and maybe + and - 15 Vdc for
the 1553 driver.

Good luck, keep us posted

Erik Baigar

unread,
Feb 17, 2005, 2:27:58 PM2/17/05
to
Alan Dicey wrote:
> You do know that ferrite core memory is non-volatile, don't you?
> However, there will have been a PROM with the clever bits in it somewhere.
Yes, I located the proms and in the meantime I
was able to analyze the type. They are 32*8, i.e. 256Bits.
I'd expect them to be interconnected to give a geometry like
256*8 by their open collector outputs. First I did not see the
scheme, but than I noticed the geometry of this memory seems
to be 128*16 where the order of the bits is changed from one
bank to the next. They must have compensated therefore during
the programming process...


> No boot process. Nothing to boot. No OS.

Yes, I see your point but it is hard for me to
believe that 128 words of code can do a substantial
job. And especially a job requiring >10000Bits of
memory.

Since the box was obviously no a mission critical part
(or was it?) is'nt it possible that the proms contain
some kind of bootloader?

Around the memory are chips I was not able to
get infos for - only numbers on them

214017
90073
8224

There is one of them per bank of prom memory. Maybe
I will find someting in an ancient databook from MMI
the proms are from...

Erik Baigar

unread,
Feb 17, 2005, 2:31:13 PM2/17/05
to
Simon Robbins wrote:
> etc. But from what someone else said, it doesn't sound like a mission
> computer so probably doesn't have that kind of feature.
Maybe, it hast this feature: There is one line connecting from
an pin on an external plug straight to the driver board for
the core memory (No other line takes this way directly).
Very possible that this input tells the driver
to "flash" the memory by applying current to all lines. But
have still not looked at the driver board...

Erik Baigar

unread,
Feb 17, 2005, 2:37:29 PM2/17/05
to
Benjamin Gawert wrote:
> I'm working with several avionics black boxes that contain "hundred of
> pins". The No. of pins says nothing about the interface type...
Yeah, I see. Lots of pins are connected from one plug directly
to another and so on. Of the >200 pins on the box's plugs "only"
100 are connected to the mainboard ;-)

> The Tornado FCS is connected to the main computer over one of the IFUs
> (Interface Units) using a 1553B (which btw. is also suitable for real-time
> tasks like for FCS, but not used in the PA200 for the purpose of
> transmitting control inputs)...

Is this protocol transmitted via differential 100Ohm lines, too? The
box seems to have got 4 serial interfaces with 3 transmiting and
3 receiving channels each. They reside RxTx interface...

Additionally there exists one optically insulated link the
the outer world via the ancient optocoupler 6N134...

Erik Baigar

unread,
Feb 17, 2005, 2:50:10 PM2/17/05
to
Alan Dicey wrote:

> Erik Baigar wrote:
> > Kent England". The sticker which was placed above the first one (maybe
> > during service or repair) reads "GEC Avionics - Airborne Display
> > Division
> > - Rochester Kent England"!!!
> As I said earlier, Marconi Avionics was renamed to GEC Avionics. It is
> possible that the unit has been back to Rochester for servicing at some
> stage
This must have been the case. Reviewing the papers I got with
the box from Abex is a sheet looking like a storage document. It
is dated from 1985 and states that the unit has been tested OK.
Maybe the box was taken out of service in this year...

> I'll take your word for it. :-) Power supplies are a black art. I

Especially supplies of those days: The transistors were rather fragile
and everything was built with discrete components. Looking at the
mechanics I noticed two locations where movable wires of power resistors
without insulation were seperated only by the epoxy coating
used to protect the boards against humidity. So I am not astonished
that these boxes must have failed rather often due to a problem
with the supply. Does every box have got its own supply? If yes,
than there are 50 or more of these aboard such an aircraft - ...


> guess the ferrite core memory needs different voltages from the TTL.

Yes, must be someting above 40 volts. At least in computers I
have seen befor.

> Thats a very big question. VDU computer terminals were first introduced
> in the '70's, and initially consisted of a "glass teletype" - displaying
> 25 lines x 80 characters or so of alphamerics. They were raster
> displays, derived from TV technology. There were a few graphic displays
> (Tektronix being the manufacturer I associate with them) that were
> vector-driven.

>
> All the extant pictures of the TV-Tabs show alphamerics and lineart
> graphics, but that doesn't mean that the displays were vector-driven.

I suppose yes!!! Let's calculate: For 25lines and 80chars you need
a minimum of 560*175pixels making more than 98000bits of information.
This is a rather big amount of core memory. BTW I think core memory
of those days was not fast enough to deliver a high enough data rate
for >5 frames per second??

> The display driver hardware is likely to be in the TV-Tab unit itself.

Yes, maybe. Perhaps the guys at BAE know a little more.
Alan, I am very happy that you have talked to them and
I am impressed, that it seems to be rather easy to get
in contact with them ;-) THANKS!

I commented some of the other postings with new information
I gained yesterday...

Erik Baigar

unread,
Feb 17, 2005, 3:02:46 PM2/17/05
to
Harry Andreas wrote:
> > BTW power is supplied to the box by a 6-pin plug called DPL06.
> > Any idea what voltages are usually used aboard an aircraft? -
> > Just to give, I will have to examine the internal supply anyway.
> typical aircraft voltage is 115V, 3Phase, 400Hz and 28 Vdc.
> I have never seen an aircraft of that vintage supply anything else.
Thanks a lot for this tip. Perhaps I will take the supply apart
next week to learn which case is present in this box.


> Internally, the power supply probably converts to 270Vdc then
> steps it down to +5Vdc, -5.2Vdc, and maybe + and - 15 Vdc for
> the 1553 driver.
As mentioned in another comment, there is no special
analog within there needing +-15V and the differential
line drivers on the RxTx board are powered by 5V directly.
-5.2V may well be possible for core memory but normally
-5.2V indicates ECL-chips. Definitively no ECL chips in there.
On the other hand I'd expect some higher voltage for the
core memory drivers...

> Good luck, keep us posted

Yes, I will do. I posted some replys to other postings
in this thread with rather technical details. Maybe no one
is interested in those but I hope to get more feedback in this
way.

Thanks again,

Erik.

Erik Baigar

unread,
Feb 17, 2005, 3:10:26 PM2/17/05
to
Harry Andreas wrote:
> typical aircraft voltage is 115V, 3Phase, 400Hz and 28 Vdc.
> I have never seen an aircraft of that vintage supply anything else.
Input rectifier has got 6 diodes, 3 tied together on one end
-> bingo, it's 3 phase. Only have got to figure out the pinout
of the input connector...
I am not sore wether to pull the boards before powering up
the unit. I do not want the power supply to toast the boards
in case of a problem in there. Do you know wether these
supplies can handle beeing turned on without load?

Cheers,

Erik.

Erik Baigar

unread,
Feb 17, 2005, 3:15:13 PM2/17/05
to
Simon Robbins wrote:
> labels on the plugs on the loom. At least that's my experience of those
> mil-spec connectors anyway. I don't know specifically about the box you
> have, but most aircraft wll have several of those ATR/half ATR form-factor
> boxes doing specific and different tasks, some may also be duplicate for
> dual-redundancy in case of failure.
That is a wise idea, of course. A substantial amount of the
weight of such an aircraft must be the avionics boxes in there ;-)

Last weekend I was in a exhibition where one can view inside
several older aircraft and there are lots of boxes. My box
is about 12kg.... ;-)

Thanks for your comment!

Harry Andreas

unread,
Feb 18, 2005, 1:38:51 PM2/18/05
to

Can't speak for Marconi, but all the boxes we've designed
can be powered up without boards installed, so that the box
can be tested stand-alone.

The cards are tested stand-alone on a purpose-built test
stand, then the cards and box are integrated and tested together.

Erik Baigar

unread,
Feb 21, 2005, 3:41:32 AM2/21/05
to
Erik Baigar wrote:
> Recently I came across an part of computer
> equipment originating from a tornado aircraft.

The box was bought from Abex and such a box
was on eBay, too.

> The label reads "Programmer electronic Control", manufactured
> by Marconi Avionics with part number 51-019-02, NSN1680-99-652-3410.

Is someone out there reading this who has bought one
of those boxes, too? I am interested in buying another of
those to have spare parts in case I will toast something
during my experiments. You may keep the collectible core
memory if desired...

Erik Baigar

unread,
Feb 21, 2005, 2:49:43 AM2/21/05
to
Harry Andreas wrote:
> > > typical aircraft voltage is 115V, 3Phase, 400Hz and 28 Vdc.
> > > I have never seen an aircraft of that vintage supply anything > > > > -> bingo, it's 3 phase. Only have got to figure out the pinout
> > of the input connector...
Somehow strange is that the supply is not symmetric. Having
a closer look shows that there must be some small transformer
using only one phase for generating supply voltages for
the chopping circuitry. This is very ugly since I now can not simply
feed in an DC after the main rectifier to power up the supply:
400Hz 3Phase is absolutely not common for a hobbyist here in
Germany ;-) Perhaps the last resort will be to use audio amplifiers,
soundcard and an transformer to simulate it...


> > I am not sore wether to pull the boards before powering up
> > the unit. I do not want the power supply to toast the boards
> Can't speak for Marconi, but all the boxes we've designed
> can be powered up without boards installed, so that the box
> can be tested stand-alone.
In the case of my box the minimum requirement I see now is,
that the supply hast to be plugged into the box and connected to
the backplane. This is necessary because the supply seems to
measure the actual voltages on the mainboard via feedback
lines.

> The cards are tested stand-alone on a purpose-built test
> stand, then the cards and box are integrated and tested together.

Ahh, thats very positive to hear. I think it was
the same in the Marconi box.

BTW: The supply has been definitely been changed in my
box since it was manufactured in 1982...

Thanks again,

any hints and suggestions are welcome,

Erik.

Erik Baigar

unread,
Feb 23, 2005, 12:42:06 PM2/23/05
to
Alan Dicey wrote:
> I'll take your word for it. :-) Power supplies are a black art. I
> guess the ferrite core memory needs different voltages from the TTL.
Yesterday I learned a lot about the supply. It's awfully complex
and the chance to power it up without having the required 400Hz
4 phase supply is near zero: Capacitors are to small for using
50Hz (the small helper transformer would be destroyed with 50Hz
anyway), built in test circuit for symmetry of input etc. etc. . .

But I figured out what voltages it generates so I should be able
to drive the mainboard directly. The only obstacle is that there is
a feedback: The supply measures the temperature of the ferrite
beads with an NTC and adjusts the driver voltage accordingly. I
can of course maesure the characteristics of the NTC which is
calibrated:
There are calibration resistors together with it on the
core plane (Thus one should be able to interchange the core planes
between
different boxes without needing to calibrate for temperature
coefficient).
But I cannot figure out the characteristics of the supply, i.e. dU/dR.
Does anybody know what the "standard temperature" in such applications
is?
I suppose the nominal driver voltage (which I know) has to be applied
at that standard temperature...

In a first try I will use a voltage for the drivers substantially
below the nominal voltage. In this way there will be enough voltage
to prevent that the drivers are damaged and on the other hand
the currents are to low to flip the magnetization in the cores.

...But memory organization is another interesting topic (seems to be
12bit words).

> > I think displays of the 70ties where not raster displays like
> > todays, but they where vector displays (like analog oscilloscopes)

> Thats a very big question. VDU computer terminals were first introduced
> in the '70's, and initially consisted of a "glass teletype" - displaying
> 25 lines x 80 characters or so of alphamerics. They were raster
> displays, derived from TV technology. There were a few graphic displays
> (Tektronix being the manufacturer I associate with them) that were
> vector-driven.
> All the extant pictures of the TV-Tabs show alphamerics and lineart
> graphics, but that doesn't mean that the displays were vector-driven.

I posted the fact that the box originates from the display section
in pprune.org - perhaps someone has interesting input on this topic...

Any piece of information is highly appreciated,

Cheers,

Erik.


P.S. Sorry for producing this lot of junk but analyzing the box
is somehow a very interesting thing and one can learn a lot
about vintage computer technology.

Erik Baigar

unread,
Feb 24, 2005, 7:50:49 AM2/24/05
to
Have added some pictures showing the power supply and
the opened core module which consists of a sandwich of
two modules. Maybe someone recognizes interesting details.

Erik Baigar

unread,
Feb 28, 2005, 12:32:30 PM2/28/05
to
Erik Baigar wrote:
> > You do know that ferrite core memory is non-volatile, don't you?
> Of course I know. 96kBit as stated on the abex site are
> quite a big amount of memory for those days. And compared
> to the ROMS (DIL14, i.e. max 2kBits per chip) its huge.
PROMS are in fact 8 pieces, each 32 bytes of memory. But they
are not connected to make a usual geometry like 256*8 or 128*16
as I'd expect if i'd contain a program in the common sense.
Instead their outputs are e.g. connected disordered (making an
open collector "or"). Their address lines are connected semi-
ordered ;-)


> > However, there will have been a PROM with the clever bits in it somewhere.
For me the PROMS on the Function decode board still look
more like some kind of action-coordination of an processor
than a hard wired program. Any suggestions?

Erik Baigar

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Feb 28, 2005, 12:37:24 PM2/28/05
to
Erik Baigar wrote:
> ...But memory organization is another interesting topic (seems to be
> 12bit words).
Memory is 8192 words of 12 bits each. The technology is the usual
standard core memory technology (i.e. not two cores per bit).
Quite common drivers those days used in this one.

Alan Dicey

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Mar 1, 2005, 5:24:14 PM3/1/05
to
Erik Baigar wrote:
>
>>>However, there will have been a PROM with the clever bits in it somewhere.
>
> For me the PROMS on the Function decode board still look
> more like some kind of action-coordination of an processor
> than a hard wired program. Any suggestions?


I don't know anything about the TV-Tab other than that I was another
Marconi Avionics product, from a different Division than that which
built the Flight Controls. I suspect that the analog circuitry was kept
with the TV-Tab itself, in the large rectangular box that is such a
feature of the rear cockpit instrumentation, behind and to either side
of the pilots head. I think that the box you have is not much more than
a "keyboard processor". Any PROMs will contain the keycodes. The box
will have been designed to service two displays, so some of the
connectors should be paired.

If the guesses we have made so far are correct, the box is largely
performing the function of the 8048 (or whatever) microcontroller in
your PC keyboard.

Erik Baigar

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Mar 7, 2005, 3:46:50 AM3/7/05
to
Alan Dicey wrote:
> Marconi Avionics product, from a different Division than that which
> built the Flight Controls. I suspect that the analog circuitry was kept
> with the TV-Tab itself, in the large rectangular box that is such a
> feature of the rear cockpit instrumentation, behind and to either side
> of the pilots head. I think that the box you have is not much more than
> a "keyboard processor". Any PROMs will contain the keycodes. The box
> will have been designed to service two displays, so some of the
> connectors should be paired.
Examining the connectors and their wiring in detail I
noticed (for a picture look at
http://www.baigar.de/TornadoComputerUnit/Connectors.jpg),
(1) that DPL06 is power (as mentioned in another posting).
(2) DPL01-DPL04 have the "same pinout" but are not really parallel.
The RxTX board contains differential line receivers and transmitters
and it is possible via multiplexers to switch three transmitter-lines
(i.e. 6 wires) and three receiver-lines (another 6 wires) to either
of the plugs DPL01-DPL04. Additionally there are some connected
between the connectors - always the same pin. But apart from the 12
differential data-lines there is no electrical connection to
the guts of the box (no GND, no power, no TTL-Signals).
(3) DPL05 is delivers two (again differential) transmit-channels
to the outer world and on one channel appear bursts of 24 rising
edges (originating from the Serial-Parallel-Converter) after powerig
on the unit on. The bursts are seperated by alternating 1.5ms of
high and 1.5ms of low level. These seem to be some kind of start-bit.
Furthermore this plug does not have GND, too. Some pins are
interconnected to DPL01-DPL04.
(4) DPL07 - the largest plug - connects to the guts of the box:
All levels TTL, power present, /reset as well. This is the only
plug supplied with a cover. The cover can be screwed onto the plug
and is attached to the box by a short piece of wire.

Questions arising from this are:

May the presence of a cover for DPL07 indicate, that the plug DPL07
was not used during normal operation? Maybe it was for diagnostic
purposes only? Or was it connected to a nearby box?

I suppose the differential lines of DPL01-DPL05 connect to remote
devices located several meters apart from the box?

Maybe DPL01-DPL04 connect to the displays and DPL05 to the Keyboard?



> If the guesses we have made so far are correct, the box is largely
> performing the function of the 8048 (or whatever) microcontroller in
> your PC keyboard.

But who is filling that big amout of memory? It is hard
for me to imagine, that there sould be 12k of memory for
pressed keys?

Thanks for discussion and input...

Erik Baigar

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Mar 13, 2005, 2:38:46 PM3/13/05
to
Erik Baigar wrote:
> Examining the connectors and their wiring in detail I
> noticed (for a picture look at
> http://www.baigar.de/TornadoComputerUnit/Connectors.jpg),
> (1) that DPL06 is power (as mentioned in another posting).
> (2) DPL01-DPL04 have the "same pinout" but are not really parallel.
> The RxTX board contains differential line receivers and transmitters
> and it is possible via multiplexers to switch three transmitter-lines
> (i.e. 6 wires) and three receiver-lines (another 6 wires) to either
> of the plugs DPL01-DPL04. Additionally there are some connected
Examining the signals on those plugs on plugs DPL01-DPL04
one of the three differential signals shows short pulses <2ms
every 16ms. They occur on all plugs in parallel and do not
run via the multiplexer. The second output shows a clock signal
(approx. 2MHz) which can be gated on the plugs individually
via the multiplexer. Interestingly the default-value is that
the clock is on and thus appears on all plugs in parallel, too.
And last but not least the third signal can routed to either
plug wia the mutliplexer and shows no activity in idele mode.

Two if the inputs run via a demux so the box decides on
which of the plugs to listen and the third one is
converted to TTL for all plugs and these four signals
run to the IRQ-board.

So I guess that if on one plug the IRQ is activated it
causes the box to "look" at this plug and than some
kind of serial communication takes place using the
clock signal.



> (3) DPL05 is delivers two (again differential) transmit-channels
> to the outer world and on one channel appear bursts of 24 rising
> edges (originating from the Serial-Parallel-Converter) after powerig
> on the unit on. The bursts are seperated by alternating 1.5ms of
> high and 1.5ms of low level. These seem to be some kind of start-bit.
> Furthermore this plug does not have GND, too.

This plug does not have got any input at all - only output
functionality and some direct connections to DPL01-DPL04.

Most interesting questions from the last posting still
remain :-(

Erik Baigar

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Mar 17, 2005, 3:14:56 PM3/17/05
to
Erik Baigar wrote:
> So I guess that if on one plug the IRQ is activated it
> causes the box to "look" at this plug and than some
> kind of serial communication takes place using the
> clock signal.
Still I was not able to cause any changes to the
signals within the box - regardless of what messages
I sent in via the per default selected DPL03's differential
receivers.
The only input lines to the box are the 4 IRQ-lines
(one on each DPL01-DPL04) and the two lines of
DPL03 which the MUX is looking at after power up.
One of these lines is even blocked by a gate signal
beeing high immediately after reset...

But so far I did not power up the memory section of
the box since the guess was that the intelligence
resides within the PROMS on the Function Decode Board...

Perhaps I will next power up the memory section
and monitor wether someting changes.

> Most interesting questions from the last posting still
> remain :-(

Especially the hypothesis that DPL07 - the only plug
which is supplied a cover fixed to the box - was not
connected during normal operation would be the most
interesting topic...

Erik Baigar

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Mar 30, 2005, 2:42:24 PM3/30/05
to
Alan Dicey wrote:
> I don't know anything about the TV-Tab other than that I was another
> Marconi Avionics product, from a different Division than that which
> built the Flight Controls. I suspect that the analog circuitry was kept
> with the TV-Tab itself, in the large rectangular box that is such a
> feature of the rear cockpit instrumentation, behind and to either side
> of the pilots head. I think that the box you have is not much more than
I see - in the meantime I found pictures of the rear cockpit
by usinng Altavista searching for pictures with "tornado rear cockpit".

> a "keyboard processor". Any PROMs will contain the keycodes. The box
> will have been designed to service two displays, so some of the
> connectors should be paired.

As stated in another posting - four connectors have identical
pinout.

> If the guesses we have made so far are correct, the box is largely
> performing the function of the 8048 (or whatever) microcontroller in
> your PC keyboard.

Having analyzed the boards a little more I found (aside a complete ALU)
three analog to digital converters (very nice made by using differential
line receivers as comparators) with different resolutions. My suspicion
is that they are the interface to the keyboard:

Hypothesis: The key switches have not been in a matrix as today but
- to reduce the number of wires needed - are used to bypass or short
resistors. Thus the DACs within the box can determine the key which
is pressed simply by measuring the resistance of the keyboard...

Have such keyboards been built for military use?

Best regards,

Erik.

Erik Baigar

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Apr 12, 2005, 2:35:47 AM4/12/05
to

Status-Report for whom may be interested:

Analyzed memory-interface: There is a 12bit-bus common for
adresses and data. Bit12 is seperate for addresses. On powering
up the unit and forcing it to read 0x000 as data one can see the
CPU running through the entire adress space.
So far identified a "relative jump command" and a "freeze"
command.
Thinking about how to simulate or read/write memory from extern
(maybe via the big plug, which at least features the
data/address-bus?)
in order to learn more about the language of the box.

Any feedback or discussion welcome...

Erik Baigar

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Apr 21, 2005, 12:00:11 PM4/21/05
to
Alan Dicey wrote:
> Erik Baigar wrote:
> >>>However, there will have been a PROM with the clever bits in it somewhere.
> > For me the PROMS on the Function decode board still look
> > more like some kind of action-coordination of an processor
> > than a hard wired program. Any suggestions?
> a "keyboard processor". Any PROMs will contain the keycodes. The box
> will have been designed to service two displays, so some of the
Further investigation shows that the box really does not seem to
be a highly specific piece of hard wired processor: There is a 12bit
system bus connecting the different operational groups. There are
commands
(identified already few of them) which trigger certain operations if
read from
memory. The IO-part contains 24bit transmitter/receiver and 16 bit
(only 12 bits settable) transmitter and rceiver. Even a timer module
whose interval can be set, is present.

> If the guesses we have made so far are correct, the box is largely
> performing the function of the 8048 (or whatever) microcontroller in
> your PC keyboard.

Yes, that seems to be a very reasonable assumption. But still
I claim that the box has to be programmed from outside prior to
operation and that the program resides in the core memory (which
would not be a problem since I think the box was not essential for
flight, was it?). Maybe programming is done vie the large plug
supplied the a cover?

Next step is placing probes to critical points to monitor the dataflow
upon placing commands into memory in order to learn more about
the machine language of the box. But my logic analyzer is broken
at the moment so there will be some break now...

Setup see www.baigar.de/TornadoComputerUnit/DeviceUnderTest.jpg

Erik Baigar

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Jul 19, 2005, 1:17:34 PM7/19/05
to
...short update:

> So far identified a "relative jump command" and a "freeze"
> command.

Freeze-Command is 000010000000 binary, relative Jump
1000rrrrrrrr where the offset is coded in rrrrrrrr.

BTW: the box consuimes about 6.5A at 5V and below 10W
at the other voltages. This is not that much, i.e. the
box does not get warmer than 30C

Still my HP1661A has a defunc floppy (!@^%&@#!$ proprietary
HP drive) and still needing time to repair this before
further investigation can be done...

Erik Baigar

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Aug 11, 2005, 8:35:52 AM8/11/05
to
Erik Baigar wrote:
> > So far identified a "relative jump command" and a "freeze"
> > command.
> Freeze-Command is 000010000000 binary, relative Jump
> 1000rrrrrrrr where the offset is coded in rrrrrrrr.

The box indeed seems to contain a general purpose
processor with program counter and one (or two,
I am not sure at the moment) accumulator registers.
There does not exist a hardware stack or priviledge
levels like on PDP11 or modern processors. The design
seems to me more like the PDP8 design.

Added rough schematic of the address generation and
program counter board SK10. Incrementing adresses is
done by setting carry. The adding engine allows
relative jumps as stated in the last posting
by adding contents of accumulator or memory the the actual
program counter:
http://www.baigar.de/TornadoComputerUnit/TornadoComputerUnitSK10.gif

Further analyzing die DataRegister boards now (SK8 und
SK9, both identical). They contain the ALU and
accumulator register...

... to be continued ....

Erik.

Erik Baigar

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Nov 7, 2005, 2:21:38 AM11/7/05
to
Erik Baigar wrote:
>
> Erik Baigar wrote:
> > > So far identified a "relative jump command" and a "freeze"
> > > command.
> > Freeze-Command is 000010000000 binary, relative Jump
> > 1000rrrrrrrr where the offset is coded in rrrrrrrr.

...in fact rrrrrrrr is drrrrrrr where d represents the
direction in which to jump, i.e. 10000000 and 00000000
will cause the unit to loop infinitely...

> I am not sure at the moment) accumulator registers.

...these registers reside on two boards (SK8 and SK9)
where each board manages 6 of the 12 bits.

By attaching a DIP switch to the memory system I am
able now to force the unit now to read certain values
from memory which can be entered via the switches.
Identified new command-groups:

1110000ddddd Causes the unit to wait for d+2 memory
cycles.

1111******** Is the group of IO-commands. There are
commands which allow me to transmit serial datagrams on
any of the plugs DPL01-DPL03 I want.

Next will be to (1) have a look at the memory system
again in order to prgram it remotely. (2) Identify
more commands.

Erik Baigar

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Nov 10, 2005, 8:16:05 AM11/10/05
to
Erik Baigar wrote:
> By attaching a DIP switch to the memory system I am
> able now to force the unit now to read certain values
> from memory which can be entered via the switches.
Picture of this added, see
http://www.baigar.de/TornadoComputerUnit/Switches.jpg

> Next will be to (1) have a look at the memory system
> again in order to prgram it remotely.

Memory system is very similar to the core memory
of a PDP8 - only built much smaller and 128 X-lines,
not 64 as in the PDP8. Great survey is given in the
book "Computer Engineering" from Bell, Mudge and
McNamara. This book describes the evolution
of minicomputers in a view of DEC. Rough schematic of
memory structure copied from this book:
http://www.baigar.de/TornadoComputerUnit/CoreMemory.jpg

Erik Baigar

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Nov 29, 2005, 12:36:26 PM11/29/05
to
Erik Baigar wrote:
> > Next will be to (1) have a look at the memory system
> > again in order to prgram it remotely.
> Memory system is very similar to the core memory
> of a PDP8 - only built much smaller and 128 X-lines,
A intense investigation shows, that the memory is split into
two banks with 4k words each. Without a connection to DPL07 the
machine always runs with A12=1 (pull up resistor). I.e. the second
bank can not be activated by the machine itself.

All pins necessary for accessingo memory appear on the large
connector DPL07 and the timing of the core memory is straight
forward (Can be seen here:
http://www.baigar.de/TornadoComputerUnit/PEC_SingleWrite.jpg).
In order to check wether there is still a 20 year old program
sitting in the core memory and to make further investigation easier
I built modified transputer based board which I want to be able to
read and write the core memory via DPL07. The diagram above
shows a single read-cycle initiated by a MEMRD pulse generated
from this external circuitry. Next step will be to write
programs to access a single core memory word first and
than to read and write the whole memory. Still I am not clear
how to prevent the machine from starting (and thus accessing
memory, too) during my external accesses. At the moment
pulling the timing generator is the way to go...

There exists a variety of complex commands for indirect
memory access which are similar to PDP8 commands. Analysis
will be easier, if testpatterns can be written to memory
via DPL07.

... may be to be continued ...

... or not.

Erik Baigar

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Dec 30, 2005, 9:58:58 AM12/30/05
to
Erik Baigar wrote:
> two banks with 4k words each. Without a connection to DPL07 the
> machine always runs with A12=1 (pull up resistor). I.e. the second
> bank can not be activated by the machine itself.
This statement has prooven to be wrong. There exists
someting like a switch-bank-command which allows the
unit to access the upper 4k words of memory.

> read and write the core memory via DPL07. The diagram above
> shows a single read-cycle initiated by a MEMRD pulse generated
> from this external circuitry. Next step will be to write
> programs to access a single core memory word first and
> than to read and write the whole memory. Still I am not clear
> how to prevent the machine from starting (and thus accessing
> memory, too) during my external accesses.

Reverse engineered the memory interface and found some
kind of DMA (direct memory access) circuitry. This provides
the needed feature via DPL07: My transputer board is now
able to halt the Programmer-Electronic-Control's CPU, to
enable the DMA mode and than to read and write the core.

Upon supplying the unit with all voltages the transputer
board allows to test the unit's core memory and to find the
optimum current for the core circuitry. Investigations show,
that the memory needs higher current to flip the cores if
it is cold and lower current in warm state (ther exists some
kind of feedback to the power supply, doing this automatically
but I do not use the built in supply since it needs 110VAC
three phase at 400Hz). Core memory seems to be OK, all
cells can be read and written.

Happy new year to all readers,

Best regards,

Erik.

Erik Baigar

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Dec 30, 2005, 1:33:11 PM12/30/05
to
Erik Baigar wrote:
>> Reverse engineered the memory interface and found some
> kind of DMA (direct memory access) circuitry. This provides
> the needed feature via DPL07: My transputer board is now
> able to halt the Programmer-Electronic-Control's CPU, to
> enable the DMA mode and than to read and write the core.
Wrote a first simple program with the commands I already
discovered:

int i = 23 ; 1 23
int j = 0 ; 2 1
clear ACCU ; 160 1536
x: add i,ACCU ; 161 257
mov ACCU,j ; 162 1282
goto x ; 163 2178
^ core memory location
^ core memory content

The program clears the accumulator and uses indirect
accesses to memory locations 1 and 2 (i and j) to
repeatedly add 23 (stored in i) to the accumulator
and store each result in j (location 2). This program
runs fine loops for many hours if desired.

So, the story is solved in principle. Maybe the last
thing to add is, that the unit consumes approx. 35W on
+5V, 1W on -5V and 35W for the core memory...

... "Live Long and Prosper" ...

Erik Baigar

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Jan 27, 2006, 8:52:00 AM1/27/06