I don't think I've ever seen it documented anywhere, but this is interesting and pretty useful for custom stuff.
At startup, the game copies 6/EE00 (in ROM w/o header, or 14/EE00 in LoROM) through 6/EEFF into 7E:1900-19FF in RAM.
These 100 bytes are the effective random number array that (I think) is used for all random number generations. There's a constantly rotating byte - 67A out of battle and 097 in battle - that gets loaded into X, then we load 1900,X into A to get our pseudorandom number.
Theoretically, the game could just load 14/EE00,X every time, but it takes one less byte each time to use the array in RAM. Still, seems like an odd way to occupy those hundred bytes of RAM...
Topic: The Pseudorandom Array (Read 724 times)