Talking of the 380Z...

[Tony Duell]

> 
> 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