Date   : Thu, 28 Jul 2005 18:24:40 +0000
From   : Jules Richardson <julesrichardsonuk@...>
Subject: Re: ARM copros, speech cartridges, real

On Thu, 2005-07-28 at 18:25 +0100, Jonathan Graham Harston wrote:
> > Message-ID: <1122463418.15644.39.camel@...>
>  
> Jules Richardson <julesrichardsonuk@...> wrote:
> > Hmm, found the ACW service manual. It says the following TUBE lines are
> > used:
> > 
> >   8x data, A0-A4, R/NW, 2E, NRS, and NIRQ.
> > 
> > It says that an interrupt scheme is used on the copro side of the Tube
> > and polling on the I/O processor (bbc B+) side of the Tube. That sounds
> > normal; I assume a copro can interrupt the I/O processor to do stuff,
> > it's just that the I/O processor can't interrupt the copro (it's polled
> > only)
> > 
> > But then further on it says of the copro that "the only source of
> > interrupts is the Tube", implying that the B+ board *can* interrupt the
> > copro. Hence I'm confused :)
>  
> You've got the previous paragraph the wrong way around.

I'm only quoting what it says in the ACW service manual :-)  I suppose
it's quite a unique document though and probably never went through much
of a review process...

> If you have access to the New Advanced User Guide or one of the
> other books I mentioned in an earlier post[1] there's explanations
> of the Tube protocol there. 

Yep, got an AUG *somewhere*, and the Tube Application Notes (or is it
Note) which I think describes it too. The ACW manual happened to be
nearest at the time...

cheers

J.