Date   : Mon, 13 Dec 2004 16:56:07 +0100
From   : John Kortink <kortink@...>
Subject: Re: Debugging ADFS and IDE drives

On 13 Dec 2004 13:48:53 +0000, Jonathan Graham Harston wrote:

>> Message-ID: <041212015502@...>
> 
>I'm having some peculiar problems with IDE drives.
> 
>If the final byte of a sector is &FE or &FF, then:
> 
>* if reading a single sector, the sector is read, but
> IDEStatus remains at &58 indicating "Ready to transfer
> data".
> 
>* if reading several sectors, then the final byte of that
>  sector is returned incorrectly, but IDEStatus returns
>  &50 indicating all data transfered.
>
>[..]

I did quite a bit of that type of code in the course of writing

http://web.inter.nl.net/users/J.Kortink/home/software/zidefs

but I'm afraid I've never seen anything like that. You'd be wise
to start suspecting your interface. Data dependency hints at
erratic signalling, bus problems, ground bounce, etc. in the
interface.

There's an easy test, really : connect the drive to a PC,
format, put the magic file on it. See what happens.


John Kortink

-- 

Email    : kortink@...         
Homepage : http://www.inter.nl.net/users/J.Kortink