Whitechapel Computer Works MG-1

[David Brownlee]

Add a few more details below - its been 20 years since I last saw one so
hopefully my memory is accurate

On 30 Nov 2014 06:51, "tony duell" <ard at p850ug1.demon.co.uk> wrote:
>
> > I just got the "Owner Operator Guide" manual for a MG-1 from a friend. I
> > did some searches and found a picture on wikipedia in the article about
> > Whitechapel Computer Works. (
> > https://en.wikipedia.org/wiki/Whitechapel_Computer_Works )
> > I also found an evaluation of the MG-1 and several contemporary
> > workstations...
> >
http://www.chilton-computing.org.uk/acd/sus/perq_papers/perq_external/p003.htm
> .> .. but then I drew a blank. It seems like these are really rare
systems.
> >
> > Does anyone have a system? Anyone need the manual?
>
> I have one. I've even found it after the move (it's on a shelf behind me
along
> with its keyboard. Not found the mouse yet, it's probably still in one of
the
> 500 or so boxes still to unpack.
>
> It's a 32016-based unix box. There are a few gotchas that I remember.
>
> It needs a good set of NiCd cells on the power control board to start it
up.
> If not, you have to do a 'jumpstart' involving connecting a 9V battery to
a connector
> on that board. Some owners added an external socket wired there to make it
> easier to so this.

Another jumpstart option was to boot one up, leave it running for a moment
and then connect it across to the dead machine

> The 32016, 32018 (FPU), MMU chips, etc are in nice turned-pin sockets. The
> EPROMs are in cheap sockets. Replacing the latter sockets will often get a
> dead machine going.

I think some of them might be early enough that they were still calling
them 16032

> The boot ROMs I have need 1.5M of RAM. There is 512K on the motherboard
> so it needs 2 RAM expansion cards. No real problem except that if it only
> has 512K it flashes the error code for 'multi bit RAM failure' on the
LED, and
> nowhere in any of the manuals I have does it say it needs the extra RAM.
> Needless to say this led me a merry dance checking the arbitration logic,
etc
> before I realised that what it was really moaning about was the fact that
I had
> not plugged in the RAM expansion cards.

There were also some 2M cards made if you needed a lot of memory. It was
possible to stack enough 512K cards that the case would not fit back on,
that did not do much to improve the machines already uncertain reliability.

5.25 floppy drive (and a flar command), there was a boot floppy with
formatting and partitioning tools for the MFM drive.

You could steal a couple of extra tracks at the end, and pick the number of
replacement blocks for bad sectors. You could also partition around a
particularly bad area of a disk.

> There is a rare adapter which adds 3 ISA slots. 8 bit ones IIRC.
>
> There is a graphics processor -- a sort of blitter -- which is built in
TTL
> and is bit serial. It wasn't fitted to later machines as it was realised
that
> it was slower than doing the operations in software on the 32016.

The memory was dual ported for cpu and screen access, and if you used the
right API you could have sections of the screen ram mapped directly into
your apps memory - Full screen width, multiple of 4pixels height if I
recall.

Came with genix (a SystemV clone) and 42nix (BSD). The later with an early
gcc -  1.4ish?

BSD Unix including /usr/games and man pages on a 20M disk, with a high res
monochrome monitor that gave you a windowing system with multiple usable
terminals plus a few token other apps all in 1.5M Ram.

I had one as a reference 'other' porting platform for a termcap/socket
based BBS for a while.

The keyboard was all kinds of awful, the mouse had a metal ball that needed
the right mat to get any traction and its buttons kept popping off. It made
the contemporary sun 3/50 seem like an amazing speed demon, and in a
university lab of 20 I'm not sure i ever saw all machines working. People
would pick an adm5 in preference to a Whitechapel - for an adm3a the
decision was less clear cut.

As you can tell,  I miss them and wish I had been able to keep hold of one
:)

> > The system could still be around so I'm going to dig around at the
> > university a while to see if I can locate it.
>
> It looks a lot like an older PC, so it is quite easy to miss.
>
> -tony