Date   : Wed, 03 Jan 2001 20:53:29 +0000
From   : Mike Tomlinson <mike@...>
Subject: Re: VFS: (BBC Video Disk) : Doomsday Project

In article <3A532EDF.6239714B@...>, Paul Wheatley
<p.r.wheatley@...> writes

>I'm fortunate enough to have a working BBC Domesday system in the office and am 
>actually working on a long term digital preservation project at the University 
>of Leeds called CAMiLEON (a little more info can be found at the URL in
my sig). 
>We're looking specifically at emulation as a preservation strategy and our plan 
>is to produce an emulation solution to run the BBC Domesday software.

Nice one.  We had a Domesday system when I worked for an Acorn dealer in
the North-west of England.  Not sure what happened to it when they went
bust.

>I believe there is only one Domesday specific ROM inside the system (the VFS), 
>although we do have a cartridge (for insertion in one of the slots on the front 
>of the machine) that contains one chip. Apparently this came with the original 
>Domesday kit (I have seen an identical cartridge with another, non-functioning 
>Domesday kit). Our guess is that its some kind of video chip. Another part to 
>the puzzle is that our Domesday system won't start up with the cartridge in 
>place (not sure if its faulty or not). Does anyone have any idea what this may 
>be? 

Cudgelling my brains, I *think* there were two ROMs - there was the VFS
as you've stated, which controls the videodisc player via the simple-
minded SCSI interface (the big 50 way ribbon cable that comes out of the
back of the Master.  This sits in the space originally intended for an
internal modem.) The VFS ROM has commands like *VOPLAY, *VOSUPERIMPOSE,
etc.

The other ROM(s) (maybe two in the cartridge) were IIRC needed to start
the actual Domesday disc running.  

Does the Master not start up at all with this ROM cartridge in?  If
someone has plugged it in with the machine on, it ill most likely have
blown up the ROM chip :(

If you whip the cartridge open, what are the labels on the EPROM chip(s)
inside?

You should have a lead connecting the BBC's RGB output to the videodisc
player, then a monitor is attached to the player's SCART output.  I
think the kit also came with a beige Acorn trackball (with a chocolate
brown ball.)

>Could it be a cartridge that was supplied with all Masters, and is not 
>actually anything specifically to do with Domesday?

no, Masters weren't supplied with ROM cartridges as standard.

-- 
"Security-wise, NT is a server with a 'Kick me' sign taped to it."
                      - Peter Gutmann