Talk:Yume Penguin Monogatari
Pirate Mode Explained
I checked out some ancient emails from 2003 which detailed the piracy that I unknowingly triggered while hacking the game into English. The mysterious mystery person who helped me out called himself "Vorname Nachname". Here's a transcript of what he sent me on June 5, 2003:
Yes. The protection is invoked right at bootup at $F894 by JSR'ing to $D424. It calculates a checksum over various memory locations (including the protection check routine itself), and if the checksums match (game is unmodified), it writes the value 00 to $7FE; if the checksums do not match, it writes the value 06 to $7FE. $7FE is then copied to $7F3, which is checked at various points in the game. The easiest solution would be to just disable the protection routine. In the .NES file, change the following bytes (first byte: original, second byte: changed) 0001D436: 85 8D 0001D437: 00 FE 0001D438: 85 07 0001D439: 01 60 This will just write $00 to $7FE and then immediately return from the protection routine, thus (hopefully) fixing all problems. As for an "older dump" working without problems, I suspect that this older dump came from a bootleg cart, and the bootleggers had already removed the protection.
I decided to post this here for historical purposes. Maybe someone can use this info in a later edit. // Foxhack 01:06, 15 May 2012 (EDT)