Move VBlank function to a file

This commit is contained in:
yenatch 2013-02-05 15:33:57 -05:00
parent a058572fd5
commit 8902050000
2 changed files with 551 additions and 540 deletions

552
main.asm
View File

@ -58,562 +58,34 @@ SECTION "start",HOME[$150]
INCBIN "baserom.gbc",$150,$283 - $150
VBlank: ; 283
push af
push bc
push de
push hl
; get vblank type
ld a, [$ff9e]
and $7
; get fn pointer
ld e, a
ld d, $0
ld hl, .VBlanks
add hl, de
add hl, de
ld a, [hli]
ld h, [hl]
ld l, a
; down to business
call JpHl
; since this is called once per frame
call GameTimer
pop hl
pop de
pop bc
pop af
reti
; 2a1
.VBlanks ; 2a1
dw VBlank0 ; 0
dw VBlank1 ; 1
dw VBlank2 ; 2
dw VBlank3 ; 3
dw VBlank4 ; 4
dw VBlank5 ; 5
dw VBlank6 ; 6
dw VBlank0 ; 7
; 2b1
VBlank0: ; 2b1
; normal operation
; rng
; scx, scy, wy, wx
; bg map buffer
; palettes
; dma transfer
; bg map
; tiles
; oam
; joypad
; sound
; inc frame counter
ld hl, $ff9b
inc [hl]
; advance rng
ld a, [$ff04] ; divider
ld b, a
ld a, [$ffe1]
adc b
ld [$ffe1], a
ld a, [$ff04] ; divider
ld b, a
ld a, [$ffe2]
sbc b
ld [$ffe2], a
; save bank
ld a, [$ff9d] ; current bank
ld [$ff8a], a
; scroll x
ld a, [$ffcf]
ld [$ff43], a ; scx
; scroll y
ld a, [$ffd0]
ld [$ff42], a ; scy
; window y
ld a, [$ffd2]
ld [$ff4a], a ; wy
; window x + 7
ld a, [$ffd1]
ld [$ff4b], a ; wx
; some time management is in order
; only have time for one of these during vblank
; bg map buffer has priority
call UpdateBGMapBuffer
jr c, .doneframeaction
; then pals
call UpdatePalsIfCGB
jr c, .doneframeaction
; dma transfer
call DMATransfer
jr c, .doneframeaction
; bg map
call UpdateBGMap
; these have their own timing checks
call SafeLoadTiles
call SafeLoadTiles2
call SafeTileAnimation
.doneframeaction
; oam update off?
ld a, [$ffd8]
and a
jr nz, .vblankoccurred
; update oam by dma transfer
call $ff80
; 403f:
; ld a, $c4
; ld [$ff46], a ; oam dma
; ld a, $28
; .loop
; dec a
; jr nz, .loop
; ret
; vblank-sensitive operations are done
.vblankoccurred
; tell other fns vblank happened
xor a
ld [VBlankOccurred], a
; dec $cfb1 until 0
ld a, [$cfb1]
and a
jr z, .textdelay
dec a
ld [$cfb1], a
.textdelay
; dec text delay counter until 0
ld a, [TextDelayFrames]
and a
jr z, .joypad
dec a
ld [TextDelayFrames], a
.joypad
call Joypad
; update sound
ld a, BANK(UpdateSound)
rst Bankswitch ; bankswitch
call UpdateSound
ld a, [$ff8a]
rst Bankswitch ; restore bank
;
ld a, [$ff98]
ld [$ffe3], a
ret
; 325
VBlank2: ; 325
; sound only
; save bank
ld a, [$ff9d]
ld [$ff8a], a
; update sound
ld a, BANK(UpdateSound)
rst Bankswitch ; bankswitch
call UpdateSound
; restore bank
ld a, [$ff8a]
rst Bankswitch
; tell other fns vblank happened
xor a
ld [VBlankOccurred], a
ret
; 337
VBlank1: ; 337
; scx, scy
; palettes
; bg map
; tiles
; oam
; sound / lcd stat
; save bank
ld a, [$ff9d]
ld [$ff8a], a
; scroll x
ld a, [$ffcf]
ld [$ff43], a ; scx
; scroll y
ld a, [$ffd0]
ld [$ff42], a ; scy
; time-sensitive fns
call UpdatePals
jr c, .vblankoccurred
; these have their own timing checks
call UpdateBGMap
call LoadTiles
; update oam by dma transfer
call $ff80
; 403f:
; ld a, $c4
; ld [$ff46], a ; oam dma
; ld a, $28
; .loop
; dec a
; jr nz, .loop
; ret
.vblankoccurred
; tell other fns vblank happened
xor a
ld [VBlankOccurred], a
; get requested ints
ld a, [$ff0f] ; IF
ld b, a
; discard requested ints
xor a
ld [$ff0f], a ; IF
; enable lcd stat
ld a, %10 ; lcd stat
ld [$ffff], a ; IE
; rerequest serial int if applicable (still disabled)
; request lcd stat
ld a, b
and %1000 ; serial
or %10 ; lcd stat
ld [$ff0f], a ; IF
ei
; update sound
ld a, BANK(UpdateSound)
rst Bankswitch ; bankswitch
call UpdateSound
; restore bank
ld a, [$ff8a]
rst Bankswitch
di
; get requested ints
ld a, [$ff0f] ; IF
ld b, a
; discard requested ints
xor a
ld [$ff0f], a ; IF
; enable ints besides joypad
ld a, %1111 ; serial timer lcdstat vblank
ld [$ffff], a ; IE
; rerequest ints
ld a, b
ld [$ff0f], a ; IF
ret
; 37f
UpdatePals: ; 37f
; update pals for either dmg or cgb
; check cgb
ld a, [$ffe6]
and a
jp nz, UpdateCGBPals
; update gb pals
ld a, [$cfc7]
ld [$ff47], a ; BGP
ld a, [$cfc8]
ld [$ff48], a ; OBP0
ld a, [$cfc9]
ld [$ff49], a ; 0BP1
and a
ret
; 396
VBlank3: ; 396
; scx, scy
; palettes
; bg map
; tiles
; oam
; sound / lcd stat
; save bank
ld a, [$ff9d]
ld [$ff8a], a
; scroll x
ld a, [$ffcf]
ld [$ff43], a ; scx
; scroll y
ld a, [$ffd0]
ld [$ff42], a ; scy
; any pals to update?
ld a, [$ffe5]
and a
call nz, ForceUpdateCGBPals
jr c, .vblankoccurred
; else
call UpdateBGMap
call LoadTiles
; update oam by dma transfer
call $ff80
; 403f:
; ld a, $c4 ; Sprites / $100
; ld [$ff46], a ; oam dma
; ld a, $28
; .loop
; dec a
; jr nz, .loop
; ret
.vblankoccurred
; tell other fns vblank happened
xor a
ld [VBlankOccurred], a
; save int flag
ld a, [$ff0f] ; IF
push af
; reset ints
xor a
ld [$ff0f], a ; IF
; force lcdstat int during sound update
ld a, %10 ; lcd stat
ld [$ffff], a ; IE
ld [$ff0f], a ; IF
ei
; update sound
ld a, BANK(UpdateSound)
rst Bankswitch ; bankswitch
call UpdateSound
; restore bank
ld a, [$ff8a]
rst Bankswitch
di
; request lcdstat
ld a, [$ff0f] ; IF
ld b, a
; and any other ints
pop af
or b
ld b, a
; reset ints
xor a
ld [$ff0f], a ; IF
; enable ints besides joypad
ld a, %1111 ; serial timer lcdstat vblank
ld [$ffff], a ; IE
; request ints
ld a, b
ld [$ff0f], a ; IF
ret
; 3df
VBlank4: ; 3df
; bg map
; tiles
; oam
; joypad
; serial
; sound
; save bank
ld a, [$ff9d]
ld [$ff8a], a
call UpdateBGMap
call SafeLoadTiles
; update oam by dma transfer
call $ff80
; 403f:
; ld a, $c4
; ld [$ff46], a ; oam dma
; ld a, $28
; .loop
; dec a
; jr nz, .loop
; ret
; update joypad
call Joypad
; tell other fns vblank happened
xor a
ld [VBlankOccurred], a
; handshake
call AskSerial
; update sound
ld a, BANK(UpdateSound)
rst Bankswitch ; bankswitch
call UpdateSound
; restore bank
ld a, [$ff8a]
rst Bankswitch
ret
; 400
VBlank5: ; 400
; scx
; palettes
; bg map
; tiles
; joypad
;
; save bank
ld a, [$ff9d]
ld [$ff8a], a
; scroll x
ld a, [$ffcf]
ld [$ff43], a ; scx
; if we can update pals, skip this part
call UpdatePalsIfCGB
jr c, .vblankoccurred
call UpdateBGMap
call SafeLoadTiles
.vblankoccurred
; tell other fns vblank happened
xor a
ld [VBlankOccurred], a
; joypad
call Joypad
; discard requested ints
xor a
ld [$ff0f], a ; IF
; enable lcd stat
ld a, %10 ; lcd stat
ld [$ffff], a ; IE
; request lcd stat
ld [$ff0f], a ; IF
ei
; update sound
ld a, BANK(UpdateSound)
rst Bankswitch ; bankswitch
call UpdateSound
; restore bank
ld a, [$ff8a]
rst Bankswitch
di
; discard requested ints
xor a
ld [$ff0f], a ; IF
; enable ints besides joypad
ld a, %1111 ; serial timer lcdstat vblank
ld [$ffff], a ; IE
ret
; 436
VBlank6: ; 436
; palettes
; tiles
; dma transfer
; sound
; save bank
ld a, [$ff9d]
ld [$ff8a], a
; inc frame counter
ld hl, $ff9b
inc [hl]
call UpdateCGBPals
jr c, .vblankoccurred
call SafeLoadTiles
call SafeLoadTiles2
call DMATransfer
.vblankoccurred
; tell other fns vblank happened
xor a
ld [VBlankOccurred], a
; update sound
ld a, BANK(UpdateSound)
rst Bankswitch ; bankswitch
call UpdateSound
; restore bank
ld a, [$ff8a]
rst Bankswitch
ret
; 45a
INCLUDE "vblank.asm"
DelayFrame: ; 0x45a
; delay for one frame
ld a, $1
ld [$cfb3], a ; was H_VBLANKOCCURRED
; Wait for one frame
ld a, 1
ld [VBlankOccurred], a
; wait for the next Vblank, halting to conserve battery
.halt\@
db $76, $00 ; XXX this is a hack--rgbasm adds a nop after this instr even when ints are enabled
ld a, [$cfb3]
; Wait for the next VBlank, halting to conserve battery
.halt
halt ; rgbasm adds a nop after this instruction by default
ld a, [VBlankOccurred]
and a
jr nz, .halt\@ ; 0x465 $f8
jr nz, .halt
ret
; 0x468
DelayFrames: ; 0x468
; wait n frames, where n is the value in c
; Wait c frames
call DelayFrame
dec c
jr nz, DelayFrames
ret
; 0x46f
RTC: ; 46f
; update time and time-sensitive palettes

539
vblank.asm Normal file
View File

@ -0,0 +1,539 @@
; VBlank is the interrupt responsible for updating VRAM.
; In Pokemon Crystal, VBlank has been hijacked to act as the
; main loop. After time-sensitive graphics operations have been
; performed, joypad input and sound functions are executed.
; This prevents the display and audio output from lagging.
push af
push bc
push de
push hl
; get vblank type
ld a, [$ff9e]
and $7
; get fn pointer
ld e, a
ld d, $0
ld hl, .VBlanks
add hl, de
add hl, de
ld a, [hli]
ld h, [hl]
ld l, a
; down to business
call JpHl
; since this is called once per frame
call GameTimer
pop hl
pop de
pop bc
pop af
reti
; 2a1
.VBlanks ; 2a1
dw VBlank0 ; 0
dw VBlank1 ; 1
dw VBlank2 ; 2
dw VBlank3 ; 3
dw VBlank4 ; 4
dw VBlank5 ; 5
dw VBlank6 ; 6
dw VBlank0 ; 7
; 2b1
VBlank0: ; 2b1
; normal operation
; rng
; scx, scy, wy, wx
; bg map buffer
; palettes
; dma transfer
; bg map
; tiles
; oam
; joypad
; sound
; inc frame counter
ld hl, $ff9b
inc [hl]
; advance rng
ld a, [$ff04] ; divider
ld b, a
ld a, [$ffe1]
adc b
ld [$ffe1], a
ld a, [$ff04] ; divider
ld b, a
ld a, [$ffe2]
sbc b
ld [$ffe2], a
; save bank
ld a, [$ff9d] ; current bank
ld [$ff8a], a
; scroll x
ld a, [$ffcf]
ld [$ff43], a ; scx
; scroll y
ld a, [$ffd0]
ld [$ff42], a ; scy
; window y
ld a, [$ffd2]
ld [$ff4a], a ; wy
; window x + 7
ld a, [$ffd1]
ld [$ff4b], a ; wx
; some time management is in order
; only have time for one of these during vblank
; bg map buffer has priority
call UpdateBGMapBuffer
jr c, .doneframeaction
; then pals
call UpdatePalsIfCGB
jr c, .doneframeaction
; dma transfer
call DMATransfer
jr c, .doneframeaction
; bg map
call UpdateBGMap
; these have their own timing checks
call SafeLoadTiles
call SafeLoadTiles2
call SafeTileAnimation
.doneframeaction
; oam update off?
ld a, [$ffd8]
and a
jr nz, .vblankoccurred
; update oam by dma transfer
call $ff80
; 403f:
; ld a, $c4
; ld [$ff46], a ; oam dma
; ld a, $28
; .loop
; dec a
; jr nz, .loop
; ret
; vblank-sensitive operations are done
.vblankoccurred
; tell other fns vblank happened
xor a
ld [VBlankOccurred], a
; dec $cfb1 until 0
ld a, [$cfb1]
and a
jr z, .textdelay
dec a
ld [$cfb1], a
.textdelay
; dec text delay counter until 0
ld a, [TextDelayFrames]
and a
jr z, .joypad
dec a
ld [TextDelayFrames], a
.joypad
call Joypad
; update sound
ld a, BANK(UpdateSound)
rst Bankswitch ; bankswitch
call UpdateSound
ld a, [$ff8a]
rst Bankswitch ; restore bank
;
ld a, [$ff98]
ld [$ffe3], a
ret
; 325
VBlank2: ; 325
; sound only
; save bank
ld a, [$ff9d]
ld [$ff8a], a
; update sound
ld a, BANK(UpdateSound)
rst Bankswitch ; bankswitch
call UpdateSound
; restore bank
ld a, [$ff8a]
rst Bankswitch
; tell other fns vblank happened
xor a
ld [VBlankOccurred], a
ret
; 337
VBlank1: ; 337
; scx, scy
; palettes
; bg map
; tiles
; oam
; sound / lcd stat
; save bank
ld a, [$ff9d]
ld [$ff8a], a
; scroll x
ld a, [$ffcf]
ld [$ff43], a ; scx
; scroll y
ld a, [$ffd0]
ld [$ff42], a ; scy
; time-sensitive fns
call UpdatePals
jr c, .vblankoccurred
; these have their own timing checks
call UpdateBGMap
call LoadTiles
; update oam by dma transfer
call $ff80
; 403f:
; ld a, $c4
; ld [$ff46], a ; oam dma
; ld a, $28
; .loop
; dec a
; jr nz, .loop
; ret
.vblankoccurred
; tell other fns vblank happened
xor a
ld [VBlankOccurred], a
; get requested ints
ld a, [$ff0f] ; IF
ld b, a
; discard requested ints
xor a
ld [$ff0f], a ; IF
; enable lcd stat
ld a, %10 ; lcd stat
ld [$ffff], a ; IE
; rerequest serial int if applicable (still disabled)
; request lcd stat
ld a, b
and %1000 ; serial
or %10 ; lcd stat
ld [$ff0f], a ; IF
ei
; update sound
ld a, BANK(UpdateSound)
rst Bankswitch ; bankswitch
call UpdateSound
; restore bank
ld a, [$ff8a]
rst Bankswitch
di
; get requested ints
ld a, [$ff0f] ; IF
ld b, a
; discard requested ints
xor a
ld [$ff0f], a ; IF
; enable ints besides joypad
ld a, %1111 ; serial timer lcdstat vblank
ld [$ffff], a ; IE
; rerequest ints
ld a, b
ld [$ff0f], a ; IF
ret
; 37f
UpdatePals: ; 37f
; update pals for either dmg or cgb
; check cgb
ld a, [$ffe6]
and a
jp nz, UpdateCGBPals
; update gb pals
ld a, [$cfc7]
ld [$ff47], a ; BGP
ld a, [$cfc8]
ld [$ff48], a ; OBP0
ld a, [$cfc9]
ld [$ff49], a ; 0BP1
and a
ret
; 396
VBlank3: ; 396
; scx, scy
; palettes
; bg map
; tiles
; oam
; sound / lcd stat
; save bank
ld a, [$ff9d]
ld [$ff8a], a
; scroll x
ld a, [$ffcf]
ld [$ff43], a ; scx
; scroll y
ld a, [$ffd0]
ld [$ff42], a ; scy
; any pals to update?
ld a, [$ffe5]
and a
call nz, ForceUpdateCGBPals
jr c, .vblankoccurred
; else
call UpdateBGMap
call LoadTiles
; update oam by dma transfer
call $ff80
; 403f:
; ld a, $c4 ; Sprites / $100
; ld [$ff46], a ; oam dma
; ld a, $28
; .loop
; dec a
; jr nz, .loop
; ret
.vblankoccurred
; tell other fns vblank happened
xor a
ld [VBlankOccurred], a
; save int flag
ld a, [$ff0f] ; IF
push af
; reset ints
xor a
ld [$ff0f], a ; IF
; force lcdstat int during sound update
ld a, %10 ; lcd stat
ld [$ffff], a ; IE
ld [$ff0f], a ; IF
ei
; update sound
ld a, BANK(UpdateSound)
rst Bankswitch ; bankswitch
call UpdateSound
; restore bank
ld a, [$ff8a]
rst Bankswitch
di
; request lcdstat
ld a, [$ff0f] ; IF
ld b, a
; and any other ints
pop af
or b
ld b, a
; reset ints
xor a
ld [$ff0f], a ; IF
; enable ints besides joypad
ld a, %1111 ; serial timer lcdstat vblank
ld [$ffff], a ; IE
; request ints
ld a, b
ld [$ff0f], a ; IF
ret
; 3df
VBlank4: ; 3df
; bg map
; tiles
; oam
; joypad
; serial
; sound
; save bank
ld a, [$ff9d]
ld [$ff8a], a
call UpdateBGMap
call SafeLoadTiles
; update oam by dma transfer
call $ff80
; 403f:
; ld a, $c4
; ld [$ff46], a ; oam dma
; ld a, $28
; .loop
; dec a
; jr nz, .loop
; ret
; update joypad
call Joypad
; tell other fns vblank happened
xor a
ld [VBlankOccurred], a
; handshake
call AskSerial
; update sound
ld a, BANK(UpdateSound)
rst Bankswitch ; bankswitch
call UpdateSound
; restore bank
ld a, [$ff8a]
rst Bankswitch
ret
; 400
VBlank5: ; 400
; scx
; palettes
; bg map
; tiles
; joypad
;
; save bank
ld a, [$ff9d]
ld [$ff8a], a
; scroll x
ld a, [$ffcf]
ld [$ff43], a ; scx
; if we can update pals, skip this part
call UpdatePalsIfCGB
jr c, .vblankoccurred
call UpdateBGMap
call SafeLoadTiles
.vblankoccurred
; tell other fns vblank happened
xor a
ld [VBlankOccurred], a
; joypad
call Joypad
; discard requested ints
xor a
ld [$ff0f], a ; IF
; enable lcd stat
ld a, %10 ; lcd stat
ld [$ffff], a ; IE
; request lcd stat
ld [$ff0f], a ; IF
ei
; update sound
ld a, BANK(UpdateSound)
rst Bankswitch ; bankswitch
call UpdateSound
; restore bank
ld a, [$ff8a]
rst Bankswitch
di
; discard requested ints
xor a
ld [$ff0f], a ; IF
; enable ints besides joypad
ld a, %1111 ; serial timer lcdstat vblank
ld [$ffff], a ; IE
ret
; 436
VBlank6: ; 436
; palettes
; tiles
; dma transfer
; sound
; save bank
ld a, [$ff9d]
ld [$ff8a], a
; inc frame counter
ld hl, $ff9b
inc [hl]
call UpdateCGBPals
jr c, .vblankoccurred
call SafeLoadTiles
call SafeLoadTiles2
call DMATransfer
.vblankoccurred
; tell other fns vblank happened
xor a
ld [VBlankOccurred], a
; update sound
ld a, BANK(UpdateSound)
rst Bankswitch ; bankswitch
call UpdateSound
; restore bank
ld a, [$ff8a]
rst Bankswitch
ret
; 45a