Re: Wondering if the other Mastering Math disks are still out there

[Antoine Vignau <antoine.vignau@laposte.net>]

Sorry, my message was a little bit short.

I've recently cracked 150 MECC disks (among those were the Mastering
Math series), I think I can discuss a little bit about the different
protection schemes used on their disks: either 3"5 or 5"25, either
simili-DOS 3.3 or ProDOS.

Basically, there were two diferent schemes:
- on 5"25 disks: change of markers (I don't have the list by me,
sorry)
- on 3"5 disks: check of block 8 (which must generate a I/O error
otherwise it is a copy)

If the disks is simili-DOS 3.3 based, the RWTS (or pseudo-RWTS) had to
get the standard markers back and that's it.
If the disk is ProDOS based, ProDOS system file had to get the right
marker and MECC.SYSTEM needed some changes.

The system is smart enough to use the right protection check based on
the medium (either 3"5 or 5"25, either DOS 3.3 or ProDOS), nice stuff.

Antoine