|Author:||LordCrass (guest: search)|
|Date:||Sat, May 26th, 2012 @ 00:24 ( . )|
Confirmed. The original disk has two spaces for the disk ID in the directory on both sides. The sectors contain $30 $31 for the disk ID bytes. When asked to change disk, the loader keeps reading track 30 sector 4, and sends the disk ID bytes back to the computer, which only checks that the second byte is now a $32.
When you convert this game to a d64, you no longer have sector headers. If this info is requested by a game, the emulator will supply it based on other data. In this case, it will always give you what was in the directory track for the disk ID bytes. When writing a d64 back to disk, it will write every sector with the ID taken from the directory.
Mismatched sector IDs are easily copied by any software nibbler.
Another way to bypass this is to change the ID in the directory to what the loader wants. Change side 1 to "01", and side 2 to "02". With Portal, this wasn't possible as the directory sectors on side 2 were used by game code instead of valid directory info. Changing the appropriate bytes would have corrupted the game.