Date   : Thu, 16 Mar 2006 00:45:29 +0000
From   : jgh@... (Jonathan Graham Harston)
Subject: Re: SASI/SCSI <>IDE, distracting thoughts.

>Message-ID: <44175461.5010000@...>
 
Jules Richardson <julesrichardsonuk@...> wrote:
> > IDE interface: two ICs minimum.
> >
> > SCSI interface: six ICs minimum and lots of bus spaghetti.
> 
> Hmm, I suppose I don't see a lot of difference in that given that it's just
> TTL - if it was 2 chips versus 20 it'd be a different matter!
 
You can do a Spectrum IDE interface with one IC. That was my
target for the BBC IDE interface, knowning it would have to be two
ICs to clean up the PGFC signal, and specifically from descrete
parts that anybody could put together after I get run over by a
bus, *not* something that required programmable logic that
required you to have some way of programming the bloody thing,
instead of just a soldering iron.
 
Plus I wanted to ensure the addressing was decoded as much as
possible - too much stuff on the Spectrum occupied the entire
available address range because the designer couldn't be bothered
to add a 5p IC.
 
-- 
J.G.Harston - jgh@...                - mdfs.net/User/JGH
There are three food groups: brown, green and ice cream.