Date   : Tue, 23 May 2006 01:39:33 +0100
From   : "Jason Watton" <jason.watton@...>
Subject: Re: 8271/1770 Opcodes

Hi Ian,

> So it looks as if the bad track is a copy protection measure, presumably
> changing the ID of track 1 to 30 and then reading from track 30 and then
> changing it back again.

If you want to **prove** this, and have a PC available, you can use OmniFlop 
(Google it): choose 'Diagnostics' with 'Get disk map' on the disk - look at 
the (ASCII) map that's produced. This usually reveals the 'fiddle', 
especially for BBC disks.

> Any ideas how to copy it?  Ripoff IX and Locksmith get confused at track 1
> and write its ID as 30 so the copy doesn't work.

IMHO, best way is manually - if you're prepared to get your hands (very) 
dirty. If you want to try, use a DOS-based program like OmniDisk or FDC (I 
think) which can both let you fiddle all the parameters. For OmniDisk, for 
example:

SEEK <track>
FORMAT TRACK <C> <H> <R> <N>... where <track>, <C>, <H>, <R>, and <N> are 
noted down from the original disk map (repeat C, H, R, N for as many sectors 
as you need).

Apologies if the PC domain is no good - if this is of any use and you want 
more gory info, contact me directly if you like (perhaps off-list). These 
same facilities, though, can be translated to OSWORD &7F's on the Beeb.

Jason.