pokecrystal-board/home/flag.asm

131 lines
1.6 KiB
NASM

ResetMapBufferEventFlags::
xor a
ld hl, wEventFlags
ld [hli], a
ret
ResetBikeFlags::
xor a
ld hl, wBikeFlags
ld [hli], a
ld [hl], a
ret
ResetFlashIfOutOfCave::
ld a, [wEnvironment]
cp ROUTE
jr z, .outdoors
cp TOWN
jr z, .outdoors
ret
.outdoors
ld hl, wStatusFlags
res STATUSFLAGS_FLASH_F, [hl]
ret
EventFlagAction::
ld hl, wEventFlags
call FlagAction
ret
FlagAction::
; Perform action b on bit de in flag array hl.
; inputs:
; b: function
; 0 RESET_FLAG clear bit
; 1 SET_FLAG set bit
; 2 CHECK_FLAG check bit
; de: bit number
; hl: pointer to the flag array
; get index within the byte
ld a, e
and 7
; shift de right by three bits (get the index within memory)
rept 3
srl d
rr e
endr
add hl, de
; implement a decoder
ld c, 1
rrca
jr nc, .one
rlc c
.one
rrca
jr nc, .two
rlc c
rlc c
.two
rrca
jr nc, .three
swap c
.three
; check b's value: 0, 1, 2
ld a, b
cp SET_FLAG
jr c, .clearbit ; RESET_FLAG
jr z, .setbit ; SET_FLAG
; check bit
ld a, [hl]
and c
ld c, a
ret
.setbit
; set bit
ld a, [hl]
or c
ld [hl], a
ret
.clearbit
; clear bit
ld a, c
cpl
and [hl]
ld [hl], a
ret
CheckReceivedDex::
ld de, ENGINE_POKEDEX
ld b, CHECK_FLAG
farcall EngineFlagAction
ld a, c
and a
ret
CheckBPressedDebug:: ; unreferenced
; Used in debug ROMs to walk through walls and avoid encounters.
ld a, [wDebugFlags]
bit DEBUG_FIELD_F, a
ret z
ldh a, [hJoyDown]
bit B_BUTTON_F, a
ret
xor_a::
xor a
ret
xor_a_dec_a::
xor a
dec a
ret
CheckFieldDebug:: ; unreferenced
push hl
ld hl, wDebugFlags
bit DEBUG_FIELD_F, [hl]
pop hl
ret