26 Apr
2007
26 Apr
'07
2:10 a.m.
Hi,
Ooer, don't say that....there used to be *lots* of them at radio rallies,
but I haven't been to one for a couple of years (planning on doing Elvaston
Castle this year though).
I suppose I could always make one, assuming the necessary ROM images are
available somewhere? I don't recall there being any custom logic in the 6502
Second Processor and my memory of the Torch Z80 2nd processor is waaay to
hazy.
Which brings me onto a second point. I actually have at least one BBC
"Master" too, I have a vague recollection that these have a connector for an
internal, as well as an external, second processor?
Do you know of any websites where I could get more info?
TTFN - Pete.
Think I'll
just get a Z80 Second Processor for my Beeb
instead (far less hassle).
I didn't think those were _that_ common... 
26 Apr
26 Apr
2:54 a.m.
On 26/04/07, Ensor <classiccmp at memory-alpha.org.uk> wrote:
[on Z80 add-on processors]
> I suppose I could always make one, assuming
the necessary ROM images are
> available somewhere? I don't recall there being any custom logic in the 6502
> Second Processor and my memory of the Torch Z80 2nd processor is waaay to
> hazy.
Acorn used a custom "ULA" chip to handle communications between the
second processor, of whatever flavour, and the host BBC computer.
This provided a handfull of FIFOs and signal lines in both directions.
Torch used a pair of PIO chips connected back-to-back to provide
simular but incompatible functionality; only their ROM software could
understand it.
The Acorn one has definiatly been emulated, in Sprow's AEM7TDMI
co-processor for example: <http://www.sprow.co.uk/bbc/armcopro.htm
> Which brings me onto a second point. I actually have at least one BBC
> "Master" too, I have a vague recollection that these have a connector for
an
> internal, as well as an external, second processor?
They do. You can connect up to both, and *CONFIGURE the system to use
which ever one you want (or neither, but not both.)
> Do you know of any websites where I could
get more info?
Sprow's page above has a link to Acorn's Tube application notes - that
should get you started on how the tube actually /worked/ ..
Whilst not wishing to remove an 8-bit thread from cc, you are probably
best asking for technical info over on the bbc micro mailing list -
gioto <http://lists.cloud9.co.uk/mailman/listinfo/bbc-micro> for
subscription machine.
Rob
27 Apr
27 Apr
11:49 p.m.
Hi,
Thanks.
I did try googling for the information before asking in here. Unfortunately,
at the time, for some reason I couldn't find much beyond "'cheese wedge'
second processors work" and "there were internal coprocessors for the
Master".
Things are a lot clearer now.
Acorn used a custom "ULA" chip to handle
communications between
the second processor....
Damn! That puts a crimp in an otherwise damn fine plan. ;-/
I honestly don't remember seeing the ULA when I last had my 6502 2nd proc
apart, but it's been the best part of 10 years....
The Acorn one has definiatly been emulated, in
Sprow's AEM7TDMI
co-processor for example: <http://www.sprow.co.uk/bbc/armcopro.htm>
Sounds like an interesting page, I'll go check it out. Thanks.
Do you know of
any websites where I could get more info?
Sprow's page above has a link to Acorn's Tube application notes - that
should get you started on how the tube actually /worked/ .. Whilst not wishing to remove an 8-bit thread from cc,
you are
probably best asking for technical info over on the bbc micro
mailing list....
Thanks, I found that one shortly after posting my previous message. I've not
subscribed yet, just been browsing the archives for now. Looks good.
TTFN - Pete.
26 Apr
26 Apr
3:13 a.m.
On 26/4/07 07:10, "Ensor" <classiccmp at memory-alpha.org.uk> wrote:
Which brings me onto a second point. I actually have
at least one BBC
"Master" too, I have a vague recollection that these have a connector for an
internal, as well as an external, second processor?
The Master series have the usual Tube connector for external processors as
well as internals. The Master Turbo (aka the Acorn AIV used for the Domesday
System) has a second internal 65C02 and the Master 512 could take 2
different co-pros. All of my stuff is out of reach till the weekend but my
Acorn page has info as well as being in need of an update :)
http://www.binarydinosaurs.co.uk/Museum/Acorn/
--
Adrian/Witchy
Binary Dinosaurs creator/curator
Www.binarydinosaurs.co.uk - the UK's biggest private home computer
collection?
2:10 p.m.
On 26/4/07 07:10, "Ensor" <classiccmp at memory-alpha.org.uk> wrote:
[SNIP]
Which brings me onto a second point. I actually have
at least one BBC
"Master" too, I have a vague recollection that these have a connector for an
internal, as well as an external, second processor?
Do you know of any websites where I could get more info?
TTFN - Pete.
Torch certainly made an "internal" Z80 co-processor for the Master (I have
one). Although the board sits internally to the case, it still connects via
the Tube- the ribbon cable loops out through a gap in the case and connects
in the normal fashion.
-Austin.
3:35 p.m.
Austin Pass wrote:
Torch certainly made an "internal" Z80
co-processor for the Master (I have
one).
They made a couple - the Communicator's just a Z80 and local RAM, whilst the
Tosca's got a "high speed" serial port local to the board.
There were also the two Torch Unix 68000 copro boards - the Neptune and Atlas
- both of those had a local Z80 and could also run CP/N (although I can't
remember if it required a ROM change on the BBC to do so)
cheers
Jules
5:45 p.m.
Hi,
Ooer, don't say that....there used to be *lots* of them at radio rallies,
My experience is that all the second processors -- no, make that all the
'cheese wedgrs' -- are rear.
Think
I'll just get a Z80 Second Processor for my Beeb
instead (far less hassle).
I didn't think those were _that_ common... I suppose I could always make one, assuming the
necessary ROM images are
available somewhere? I don't recall there being any custom logic in the 6502
I think you've forgotten the 'TUbe ULA' That's a 40 pin custom chip that
handles the communication between the Beeb and the second procrossor, and
AFAIK it was never fully documetned by Acorn.
Second Processor and my memory of the Torch Z80 2nd
processor is waaay to
hazy.
The Torch Z80 board did, indeed, use only sandard chips.
-tony
6244
days inactive
6246
days old
6 comments
6 participants
participants (6)
-
ard＠p850ug1.demon.co.uk -
austin＠ozpass.co.uk -
classiccmp＠memory-alpha.org.uk -
julesrichardsonuk＠yahoo.co.uk -
robert＠irrelevant.com -
witchy＠binarydinosaurs.co.uk