Date   : Wed, 08 Mar 2006 23:05:53 +0000
From   : jgh@... (Jonathan Graham Harston)
Subject: Re: Warning: Sad case on list!

Fragula <fragula@...> wrote:
> However i'll probably be contacting you for an IDE board fairly soon
> anyway. Have to read up properly on your website, as i'm not too sure
> what (apart from sector size) what the peculiarities are, study the
 
I don't know of any peculiarities. It connects to a standard
ATA/IDE drive interface, HADFS and the ADFS patch uses standard
ATA/IDE read and write sector commands &20 and &30. They have
worked with every drive I've tried so far...
 
> diagrams, whether there is any mileage on a 16 bit board over an 8 bit.
 
The 8-bit board is a simple 2-chip interface. The 16-bit board is
a 7-chip interface. From the filing system point of view they both
look like 8-bit interfaces as no 8-bit filing system uses sector
sizes other than 256 bytes.
 
ADFS and HADFS make no attempt to read or write the high byte of
each IDE word. User programs can access the full 16-bit data
words.
 
The main problem with the 16-bit board is that assembling it is
slightly beyond my soldering skills. I can suply the bare boards
for self-assembly. The assembly includes a slight board
modification to fix a tracking error.
 
> Whether you got the address decoding right, ;-> and how this will fit in
 
The 8-bit board decodes into &FC40 with one relection at &FC50.
The 16-bit board decodes into &FC40 with no reflections.
 
I've been using an 8-bit board, Sprow's RAM Card and my MIDI
interface all plugged in together.
 
> I've never used an MDFS, but guess it is very noisy, and the server room
 
It's almost silent. The A5000 makes more noise. Occasionally I
notice it defragging or something when there's no other activity.
 
-- 
J.G.Harston - jgh@...                - mdfs.net/User/JGH
RISC OS Choices System - http://mdfs.net/Software/RISCOS