Date   : Tue, 26 Jul 2005 17:59:26 +0200 (BST)
From   : Johan Heuseveldt <johan@...>
Subject: Re: ARM copros, speech cartridges, real time clocks,etc

Hi Eelco,

On Tue 26 Jul, Eelco Huininga wrote:

> > Actually, it'd be nice if someone was looking at ULA replacements for
> > the Acorn machines anyway - all the other parts can still be sourced
> > pretty easily, but it's presumably reasonably difficult to find a ULA
> > (particularly wihtout destroying another machine in the process)
> 
> I think the most reasonable solution would be to program a FPGA to act as
> an Tube/Serial/Video ULA.

There's a misconception here.

Serial and Video ULA's belong to the Beeb as system properties. The
Tube ULA belongs to the CoPro, for which the host-side is seen by the
Beeb. The Tube is not a single interface to connect whatever, and how
much CoPro's to, but every CoPro presents his own Tube interface to
the Beeb. Only for this reason alone, you can't connect two CoPro's on
the Tube connector.
That is quite a difference from the 1MHz bus, to put it mildly! :-)

Of course the software side is even a magnitude of the issues involved!

The difference has to be very clear, and is a very basic start if you
would like to start playing with multiple CoPro's/2ndProc's attached! :-)


greetings,
Johan

-- 
Johan Heuseveldt <johan@...              >
  aka  waarland

  The best place is a Riscy place
 
Every word is like an unnecessary stain on
silence and nothingness. - Beckett