On Tue, 2005-07-05 at 20:13 +0100, Tony Duell wrote:
What about hacking around with the Acorn SASI
controller, e.g. the one in
your ACW? I assume you have schematics, etc for that.
Yep, could do - plus I've got the schematics for the Torch one
somewhere. Just wanted to check that there wasn't anything funny about
IIRC Torch made a SCSI controller for the Beeb, it was used with a ROM
called SCISFS. If you've found one of those you're very lucky, I am told
that fewer than 100 were made.
Hmm... my Torch 725 has a Torch SCSI board in it - although I recall
that it's not a complex board at all, just a handful of TTL chips.
That sounds like the Beeb one. Maybe it's Torch Beeb SCSI systems that
are rare -- there's a plinth to go under the monitor that contains a
floppy drive, hard drive, SCSI interface, etc.
Nice - I've not seen one of the PIO boards before.
And agreed, I don't
think there's a PROM on the standard FDC either.
Mine is not currently in my 380Z, in fact it's never been in my 380Z. It
turned up in a box of Apple ][ cards I was given (and FWIW, some of those
Apple boards are not common -- things like speech input boards, etc). I
must find time to trace out the schematic, wire-wrap the PIOs to
connectors in the prottyping area, and stick it in the 380Z.
The PIOs and CTC are in wire-wrap DIL sockets. The bus side is wired up
by traces on the PCB, the user is intended to wire-wrap to the
appropriate pins on the sockets. There's space on the PCB for a few more
ICs if you need to fiddle around with signals, and space for at least one
IDC connector to bring your I/O signals off-board to connectors on the
back of the 380Z.
It should be piossible to work out what COS looks
for from the source
listings. I am not sure, though, if the version on
vt100.net is recent
enough to support this. It's a pity nobody has the COS 3.4 or COS 4.0
listings.
Hmm yep, that is a shame. I think a lot changed between COS 3.0 and
3.4...
One day I muast disassemnle COS 3.4,,,
I still wonder if the PC keyboard interface would
be a good idea. It
would have an adantage to you that the public at Bletchley could bash
away on a PC keyboard without risking anything too rare.
Yep, that is a good point. Mind you, we've got a couple of VT220s with
dead LOPTs - they'd make nice input-only devices!
I would suggest an LM201-RML interface, except that the LK201 needs +12V,
which is not available on the 380Z keyboard connector (+5V and -12V are).
Using that keyboard would be more work, therefore.
-tony