Date   : Fri, 14 Sep 2007 09:02:26 +0100
From   : chris.priest@... (Chris Priest)
Subject: IDE Interface and Level 3

Jonathan Graham Harston wrote:
> That's odd, it works here.
>   
Yes, I don't know what I did, but it worked for me as well, must have 
been doing something wrong somewhere :)

>  
> I left mine forty minutes to boot up :)
>   
Eeek!  with the drive size set to 128mb, I timed it at just over 5 
minutes to start up, not too bad :)

Hmm, actually thats interesting, What size was drive 0 for you?  Just 
wondering if the time waiting for boot in exponential if 128mb is 5mins 
for me, and yours was 40mins, either it is exponential in time or you 
had a whopping big drive :)

>> as opposed to assigning all 258mb to drive 0, while this worked for
>> drive 0, it correctly created a partition at 64mb, partitioning drive 1
>> didn't work using my modified code, it wrote sector 0, but hung up when
>> attempting to write sector 1.
>>     
>  
> ADFS doesn't partition drives. Logical drive 1 starts at exactly
> 512*1024*1024 bytes into the drive. The IDE sector address is the entire
> ADFS sector address, which includes the drive number in bit 21.
>   
Ah right, OK, I think I understand now, I knew it wasn't exactly 
partitions, my bad, wrong choice of words :)

>  
>   
>> Could this be because the drive is bigger than 256mb?  256/2 = 128 (8
>> bit) /2 = 64mb ?
>>     
>  
> No. It's 'cos they aren't partitions. They are hardwired at 512M - the
> maximum the ADFS API will access. If you wish you could modify the IDE
> patch to pass the ADFS sector address to the IDE device with the 'drive'
> bit moved down to chop a drive into smaller pieces.
>   
It's working with drive 0 at 128mb, for the purposes of the interactive 
IT museum we are creating with it, thats ample space for it :)

I think I shall investigate with my own setup, just for the sheer hell 
of it of course :)

Thanks for the tips and pointer J.

Best Regards
Chris