Date   : Fri, 31 Dec 2010 22:27:59 +0000
From   : rs423@... (Mick Champion)
Subject: Patching a CF card patched ADFS

Hello all,


Having recently purchased a retro clinic CF hard drive kit, I'd be very
grateful for a few pointers as to how I can further patch the already
patched CF ADFS. This in order to run an original ADFS and patched ADFS
at the same time (although obviously not paged in at the same time). To
be clear, I want to hang the CF HD and ST506 HD's on the same cable and
switch between the ADFS versions to copy files from my one remaining
good hard disc before it's too late. Drive 0 died just over a week ago.
I think one of the heads fell of based by the hair raising screeching
sound it made :-(


First the easy bit.  How do I change the filing system number on the
patched ADFS from 8 to something else? This so the highest priority ADFS
doesn't stop calls getting to lowest priority ADFS.   Senile bloke here
can't remember how he did this in 2004 for the patched ADFS on GoMMC.
Is it just a single byte in the ROM header that needs altering? If so,
the byte I'd need to alter would be really good to know. Is that all I'd
need to do to access both versions of ADFS? So far, all I've managed to
do is get CF ADFS to respond to *CFFS. *ADFS gives "Bad command" despite
being installed lower down the pecking order. I presume as CF ADFS is
answering all calls to file system 8?


Secondly the harder bit I guess. The hard disc is fixed at &FE40 - $FE47
on the 1Mhz bus address . Normally the CF HD is too, however I have been
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
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. :-)


Thanks in advance and happy new year to all,


Mick.