Acorn (Was Re: Reading PDP-8 paper tapes)

From: Tony Duell <ard_at_p850ug1.demon.co.uk>
Date: Tue Jul 1 16:31:58 2003

> > I have a couple of Acorn Systems (one 6502, the other 6809-based). I am
> > always looking for any of the more unusual I/O cards for them....
>
> OK, refresh my memory here... what Acorn 6809 system would that be?

Well, it's basically a System 4 (4 3U racks, top one contianing a pair of
5.25" floppies, bottom one cotnaining a row of Eurocards). The CPU board
has a 6809 processor, monitor ROM, keyboard interface, etc. There's also
7 of the 8K SRAM cards, an 80 column VDU card, the 8271-based FDC, and
IIRC one of the serial/parallel I/O cards

I have no idea if it ever made commercial production. I do have a spare
CPU card for it (obtained separately) which has the monitor ROM with
routines for the 40 colum 'Teletext' VDU card. I also have the CPU board
manual (giving schematics and source code for the 40 column version of
the ROM) and it looks like a commercial product.

>
> I was only aware of two - one by Brian Jones which was a large hand-
> made breadboarded circuit he did as an experiment, and which ran FLEX,

Mine runs Flex....

> Other obscure Acorn kit that I have: the "Prophet" - a version of
> the Atom targetted at businesses. Never seen a single mention of

Interesting. Never heard of that one...

> Some day I'll photograph my acorn goodies and let you know
> what's available. Any cards I can put in a padded envelope

Let me know what 'spare' cards you have, then :-)....

> PS My main 'beeb' project before I transferred to VLSI CAD was
> the Teletext adapter. I found the source code recently if anyone
> wants it. I can't see Acorn giving me a hard time over
> releasing it after all these years...

I'd be interested in seeing it sometime. I don't have the teletext
adapter (yet!), but I do have the schematics and loads of SAA50x0 series
chips so I could always have a go at making one...

-tony
Received on Tue Jul 01 2003 - 16:31:58 BST