Date   : Thu, 11 Mar 2010 00:14:05 +0000
From   : pete@... (Pete Turnbull)
Subject: Tube on the Archimedes

On 10/03/2010 20:46, Jules Richardson wrote:
> Theo Markettos wrote:
>> A post in comp.sys.acorn.programmer set me wondering about Tube support on
>> the Archimedes.
>>
>> We all know that the BBC was used as a host system for ARM development.  But
>> is there any other Tube support out there, perhaps with the Archimedes as
>> host?  I know there was a Tube podule - was there any software for it? 

Not for an Archimedes.  It was designed the other way around, and was 
installed in an A500 to attach it to a Beeb for development, the Beeb 
being the I/O processor and the A500 the copro, as Theo says.

> I have one of the TUBE podules, but in storage and I don't think I grabbed a 
> photo of it - I can't recall what IC's are on it now. Could it even be used 
> for talking to TUBE "slaves", or was it wired only so that an ARM-based 
> machine could act as a copro for a Beeb?

Only the latter -- A500 as copro.  The Tube podule has a Tube ULA (of 
course!), a 74HC244 next to it, and and 74HC244 and a 74HC245 at the 
other side, near the  backplane connector.  2 resistors, 2 electrolytic 
caps, and 4 decoupling caps complete the electronics.  There's no 
firmware on it, so you would have to soft-load something onto the A500 
to even use it a a Beeb copro, and I don't think that ever existed for 
anything except development versions of Arthur.  I remember Roger 
telling me it wouldn't work on an Archimedes, and I guess no-one ever 
adapted the code.

>> Were there any other Tube applications for the Arc?
> 
> Remember that a BBC podule existed - so I suppose that was the preferred route 
> for an Arc interfacing to BBC peripherals; I'm not sure if they ever intended 
> for mere mortals to talk to Beeb copros from a RISC machine (I've got one of 
> those podules, too - it has a user port, analogue port, and 1MHz bus interface).

That was the I/O Podule.  It also had provision for a MIDI interface, 
and some were sold with that pre-fitted.

-- 
Pete                                           Peter Turnbull
                                               Network Manager
                                               University of York