Date   : Wed, 27 Jul 2005 12:56:28 +0200 (BST)
From   : Johan Heuseveldt <johan@...>
Subject: Re: ARM copros, speech cartridges, real timeclocks, etc

Hi Jules,

On Tue 26 Jul, Jules Richardson wrote:
> On Tue, 2005-07-26 at 23:22 +0200, Johan Heuseveldt wrote:

> > It was exactly the point that no interrupt system was in use, ever. But
> > the Tube ULA /has/ it on board. In the light of more than one CoPro, this
> > is, or could be, a valueble addition, as it is present in the hardware,
> > ready to be used, though needing new software.
> 
> You know, for some reason

Nothing devious or heavenly inspired!
It's just in the (New) Advanced User Guide. It's only mentioned, mostly in
tables. (NAUG table on page 329)

The NAUG has much more information than the older AUG. The AUG for the
Master from WE (Watford Electronics) also has a lot of valuable details,
in particular the software protocols.

The all have errors, but together they are accurate enough.


> I think that the ACW (and possibly the ABC3xx machines) perhaps did make
> use of an interrupt mechanism. I just can't remember who told me that and
> exactly what I was told now though! I've got the ACW schematics; I'll have
> to have a look and see. Maybe it wasn't through the Tube though and wired
> in via some other way...  (of course the BBC I/O processor side ran BOS, so
> it's entirely possible the Tube-handling code was entirely different to a
> normal BBC)

Ah! Interesting.
If you find any confirmation on that, please let me (us) know.


greetings,
Johan

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

  The best place is a Riscy place
 
If it pours before seven, it has rained by eleven.