Re: Need replacement disks for Tower of Myraglen

[Andy McFadden <fadden@fadden.com>]

Michael J. Mahon <mjmahon@aol.com> wrote:
> If this is the case, then you will need to either use a low-level
> nibble copy program to create the block errors it checks for, or
> find the checking routine and disable it.
[...]
> Since it prints out the message, you can use a block editor to search
> the disk for that string, then examine code in the vicinity to see
> what is printing it.  Patch that so that it enters the monitor instead
> of printing, and examine the stack to see where it was called from,
> and proceed back in this way until you find the "verification" code,
> then disable it.

Create images from the "cracked" image and the good blocks from the original,
then diff the binaries (under Linux, "xxd" the disks and compare them with
"diff").  That'll tell you which blocks were modified by the crackers.  If
you get lucky, and there's not a lot of fuzz from saved games or the crack
screen, you'll be able to find the block quickly.

The trouble comes if there's actual data on the unreadable blocks.

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