Files
open-roms/c64/kernal/iostack/setfls.s
T

24 lines
483 B
ArmAsm

// #LAYOUT# STD * #TAKE
// #LAYOUT# * KERNAL_0 #TAKE
// #LAYOUT# * * #IGNORE
//
// Official Kernal routine, described in:
//
// - [RG64] C64 Programmers Reference Guide - page 297
// - [CM64] Computes Mapping the Commodore 64 - page 238
//
// CPU registers that has to be preserved (see [RG64]): .A, .X, .Y
//
SETFLS:
// There are 6 sane ways to implement this routine,
// I hope this one will not cause similarity to CBM code
sta LA
sty SA
stx FA
rts