90 lines
983 B
ArmAsm

.segment "ZEROPAGE"
PAD_STATE: .res 2 ;one byte per controller
PAD_STATEP: .res 2
PAD_STATET: .res 2
.importzp TEMP
PAD_BUF =TEMP+1
.include "nes.inc"
.segment "CODE"
.export _pad_poll, _pad_trigger, _pad_state
;unsigned char __fastcall__ pad_poll(unsigned char pad);
_pad_poll:
tay
ldx #0
@padPollPort:
lda #1
sta CTRL_PORT1
lda #0
sta CTRL_PORT1
lda #8
sta <TEMP
@padPollLoop:
lda CTRL_PORT1,y
lsr a
ror <PAD_BUF,x
dec <TEMP
bne @padPollLoop
inx
cpx #3
bne @padPollPort
lda <PAD_BUF
cmp <PAD_BUF+1
beq @done
cmp <PAD_BUF+2
beq @done
lda <PAD_BUF+1
@done:
sta <PAD_STATE,y
tax
eor <PAD_STATEP,y
and <PAD_STATE ,y
sta <PAD_STATET,y
txa
sta <PAD_STATEP,y
ldx #$00
rts
;unsigned char __fastcall__ pad_trigger(unsigned char pad);
_pad_trigger:
pha
jsr _pad_poll
pla
tax
lda <PAD_STATET,x
ldx #$00
rts
;unsigned char __fastcall__ pad_state(unsigned char pad);
_pad_state:
tax
lda <PAD_STATE,x
ldx #$00
rts