Killer Instinct (SNES)
This game has anti-piracy features.
Failing any of the below tests will write the string I PiRatE to RAM address $7E0200 and then display the above unauthorized device message on boot up.
Boot State Test
Almost immediately after booting, the Emulation Flag and Direct Page register are examined. The console already being in Native Mode and/or the Direct Page register containing a non-zero value fails the test as these are evidence that another program (e.g., a backup unit menu) was running before the game had a chance to boot.
If the Reset Vector was at the top of the stack, the test fails. Explained in more detail in the next section.
The beginning of RAM (range $7E0000-7E1FFF) is searched for three types of fingerprints left behind by the unauthorized devices. The two jump tests, along with the stack test mentioned in the previous section, are looking for the various methods that attached hardware can use to switch from its programming to that of the game cartridge.
Checks for operation $4Cxxxx, where xxxx is the Reset Vector.
Indirect Jump $6C
Checks for operation $6CFCFF, an indirect jump.
Incrementing RAM Pattern
Checks for the incrementing 32 byte string $60-7F (i.e., 60,61,62 ... 7D,7E,7F). This includes lowercase ASCII characters a-z.
The Killer Instinct series
|Arcade||Killer Instinct • Killer Instinct 2|
|Game Boy||Killer Instinct|
|Nintendo 64||Killer Instinct Gold|