Date   : Fri, 16 Jan 2004 08:42:51 +0000 (GMT)
From   : Sprow <info@...>
Subject: Re: IDE Interface for BBC

In article <040116015502@...>,
   Jonathan Graham Harston <jgh@...> wrote:
> > Message-ID: <040113025505@...>
>  
> jgh@... (Jonathan Graham Harston) wrote:
> > Anyway, it passes electrical tests, and appears in the memory map. Now to
> > try and actually tansfer some data!
>  
> Well, on reading it responds correctly, but try as I might, I can't get it
> to respond to commands. 

[snip]
 
> But the 1MHz bus asserts WR as:
>  
>      ______________                   ______________________________
> WR                 \                 /
>                     \_______________/
>  
>  
> I think I need to somehow push the WR signal along to assert from the
> middle of the valid data.

There is no write strobe on the 1MHz bus, or read strobe, just RnW which is
different.
Anyway, why not just try inverting - clearly the IDE drive is latching the
data on the falling edge,
Sprow.