[BBC-Micro] Patching a CF card patched ADFS

[Mick Champion]

J.G.Harston wrote:
>
>> given an alternate 1Mhz bus PAL (cheers Mark) for the CF hard disc. That
>> PAL alters the CF HD bus address to &FE50-&FE57. Would it be a simple
>>     
>
> Simplest way is to use SCSItoIDE[1] to dump the data from the SCSI device
> over to the IDE device. That needs an IDE interface where you can change
> the address such as the v1.05 8-bit card or the one you have from Mark.
>
> [1]http://mdfs.net/Info/Comp/BBC/IDE/ADFS
>   
Wow! That looks just the ticket.  Thanks. I will certainly give that a 
whirl. I was going to copy each file manually. The largest is 640k I 
think?? so Sprows arm co-pro would have had enough memory to load that, 
but if your program works with my dodgy remaining HD, then that would be 
perfect :-)



>   
>> First the easy bit.  How do I change the filing system number on the
>> patched ADFS from 8 to something else? ...
>> Is it just a single byte in the ROM header that needs altering? If so,
>>     
>
> No, you'd need to change the ServiceCall 18 (SelectFS) code, the Sevice
> &25 (FSInfo) code and the *command code that recognises "*[F]ADFS".
>   
Oh, I didn't realise the service call was different. Thanks for that. I 
still may give this a go.




>   
>> Secondly the harder bit I guess. The hard disc is fixed at &FE40 - $FE47
>> matter to patch CF ADFS to work from the higher address? I'm happy to
>> patch the ROM myself if I knew where to peek and what to poke it with. :-)
>>     
>
> If you really want to get your hands dirty, the disassembly is at
> http://mdfs.net/Info/Comp/BBC/ADFS  I only got as deep into it as
> I needed to replace the hardware drivers. You will discover that
> the SCSI code accesses the hardware in many strange and wonderous
> ways scattered all around the code. ;)
>
>   
I had a look there but don't see v1.3x there. I know v1.50 is for the 
master, what is v2.10?  Master Compact?



Cheers,


Mick