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-rw-r--r--home/vblank.asm384
1 files changed, 142 insertions, 242 deletions
diff --git a/home/vblank.asm b/home/vblank.asm
index 54a99bc99..38dc02800 100644
--- a/home/vblank.asm
+++ b/home/vblank.asm
@@ -12,27 +12,23 @@ VBlank:: ; 283
push bc
push de
push hl
-
-; get vblank type
- ld a, [$ff9e]
- and $7
-
-; get fn pointer
+
+ ld a, [hVBlank]
+ and 7
+
ld e, a
- ld d, $0
+ 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 _hl_
-
-; since this is called once per frame
+
call GameTimer
-
+
pop hl
pop de
pop bc
@@ -41,14 +37,14 @@ VBlank:: ; 283
; 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
+ dw VBlank0
+ dw VBlank1
+ dw VBlank2
+ dw VBlank3
+ dw VBlank4
+ dw VBlank5
+ dw VBlank6
+ dw VBlank0 ; just in case
; 2b1
@@ -66,117 +62,91 @@ VBlank0:: ; 2b1
; joypad
; sound
-; inc frame counter
+ ; inc frame counter
ld hl, $ff9b
inc [hl]
-
-; advance rng
+
+ ; advance random variables
ld a, [rDIV]
ld b, a
ld a, [hRandomAdd]
adc b
ld [hRandomAdd], a
-
+
ld a, [rDIV]
ld b, a
ld a, [hRandomSub]
sbc b
ld [hRandomSub], a
-
-; save bank
- ld a, [hROMBank] ; current bank
- ld [$ff8a], a
-
-; scroll x
+
+ ld a, [hROMBank]
+ ld [hROMBankBackup], a
+
ld a, [hSCX]
ld [rSCX], a
-; scroll y
ld a, [hSCY]
ld [rSCY], a
-; window y
ld a, [hWY]
ld [rWY], a
-; window x + 7
ld a, [hWX]
ld [rWX], a
-
-; some time management is in order
-; only have time for one of these during vblank
-
-; bg map buffer has priority
+
+ ; There's only time to call one of these in one vblank.
+ ; Calls are in order of priority.
+
call UpdateBGMapBuffer
- jr c, .doneframeaction
-
-; then pals
+ jr c, .done
call UpdatePalsIfCGB
- jr c, .doneframeaction
-
-; dma transfer
+ jr c, .done
call DMATransfer
- jr c, .doneframeaction
-
-; bg map
+ jr c, .done
call UpdateBGMap
-
-; these have their own timing checks
+
+ ; These have their own timing checks.
+
call Serve2bppRequest
call Serve1bppRequest
call AnimateTileset
-
-.doneframeaction
-; oam update off?
+
+.done
+
ld a, [hOAMUpdate]
and a
- jr nz, .vblankoccurred
-
-; update oam by dma transfer
+ jr nz, .done_oam
call hPushOAM
-; @PushOAM:
-; ld a, Sprites >> 8
-; ld [rDMA], a
-; ld a, $28
-; .loop
-; dec a
-; jr nz, .loop
-; ret
-
-
-; vblank-sensitive operations are done
-
-.vblankoccurred
-; tell other fns vblank happened
+.done_oam
+
+
+ ; vblank-sensitive operations are done
+
xor a
ld [VBlankOccurred], a
-
-; dec OverworldDelay until 0
+
ld a, [OverworldDelay]
and a
- jr z, .textdelay
+ jr z, .ok
dec a
ld [OverworldDelay], a
-
-.textdelay
-; dec text delay counter until 0
+.ok
+
ld a, [TextDelayFrames]
and a
- jr z, .joypad
+ jr z, .ok2
dec a
ld [TextDelayFrames], a
-
-.joypad
+.ok2
+
call Joypad
-
-; update sound
+
ld a, BANK(_UpdateSound)
- rst Bankswitch ; bankswitch
+ rst Bankswitch
call _UpdateSound
- ld a, [$ff8a]
- rst Bankswitch ; restore bank
-
-;
+ ld a, [hROMBankBackup]
+ rst Bankswitch
+
ld a, [hSeconds]
ld [$ffe3], a
-
+
ret
; 325
@@ -184,20 +154,16 @@ VBlank0:: ; 2b1
VBlank2:: ; 325
; sound only
-; save bank
ld a, [hROMBank]
- ld [$ff8a], a
-
-; update sound
+ ld [hROMBankBackup], a
+
ld a, BANK(_UpdateSound)
- rst Bankswitch ; bankswitch
+ rst Bankswitch
call _UpdateSound
-
-; restore bank
- ld a, [$ff8a]
+
+ ld a, [hROMBankBackup]
rst Bankswitch
-
-; tell other fns vblank happened
+
xor a
ld [VBlankOccurred], a
ret
@@ -212,77 +178,60 @@ VBlank1:: ; 337
; oam
; sound / lcd stat
-; save bank
ld a, [hROMBank]
- ld [$ff8a], a
-
-; scroll x
+ ld [hROMBankBackup], a
+
ld a, [hSCX]
ld [rSCX], a
-
-; scroll y
ld a, [hSCY]
ld [rSCY], a
-
-; time-sensitive fns
+
call UpdatePals
- jr c, .vblankoccurred
-
-; these have their own timing checks
+ jr c, .done
+
call UpdateBGMap
call Serve2bppRequest@VBlank
-; update oam by dma transfer
+
call hPushOAM
-; @PushOAM:
-; ld a, Sprites >> 8
-; ld [rDMA], a
-; ld a, $28
-; .loop
-; dec a
-; jr nz, .loop
-; ret
-
-.vblankoccurred
-; tell other fns vblank happened
+.done
+
xor a
ld [VBlankOccurred], a
-
-; get requested ints
+
+ ; get requested ints
ld a, [rIF]
ld b, a
-; discard requested ints
+ ; discard requested ints
xor a
ld [rIF], a
-; enable lcd stat
+ ; enable lcd stat
ld a, %10 ; lcd stat
ld [rIE], a
-; rerequest serial int if applicable (still disabled)
-; request lcd stat
+ ; rerequest serial int if applicable (still disabled)
+ ; request lcd stat
ld a, b
and %1000 ; serial
or %10 ; lcd stat
ld [rIF], a
-
+
ei
-; update sound
ld a, BANK(_UpdateSound)
- rst Bankswitch ; bankswitch
+ rst Bankswitch
call _UpdateSound
-; restore bank
- ld a, [$ff8a]
+ ld a, [hROMBankBackup]
rst Bankswitch
di
-
-; get requested ints
+
+ ; get requested ints
ld a, [rIF]
ld b, a
-; discard requested ints
+ ; discard requested ints
xor a
ld [rIF], a
-; enable ints besides joypad
+ ; enable ints besides joypad
ld a, %1111 ; serial timer lcdstat vblank
ld [rIE], a
-; rerequest ints
+ ; rerequest ints
ld a, b
ld [rIF], a
ret
@@ -292,21 +241,18 @@ VBlank1:: ; 337
UpdatePals:: ; 37f
; update pals for either dmg or cgb
-; check cgb
ld a, [hCGB]
and a
jp nz, UpdateCGBPals
-
-; update gb pals
+
+ ; update gb pals
ld a, [$cfc7]
ld [rBGP], a
-
ld a, [$cfc8]
ld [rOBP0], a
-
ld a, [$cfc9]
ld [rOBP1], a
-
+
and a
ret
; 396
@@ -320,77 +266,58 @@ VBlank3:: ; 396
; oam
; sound / lcd stat
-; save bank
ld a, [hROMBank]
- ld [$ff8a], a
-
-; scroll x
+ ld [hROMBankBackup], a
+
ld a, [hSCX]
ld [rSCX], a
-; scroll y
ld a, [hSCY]
ld [rSCY], a
-
-; any pals to update?
+
ld a, [hCGBPalUpdate]
and a
call nz, ForceUpdateCGBPals
- jr c, .vblankoccurred
-; else
+ jr c, .done
+
call UpdateBGMap
call Serve2bppRequest@VBlank
-
-; update oam by dma transfer
+
call hPushOAM
-; @PushOAM:
-; ld a, Sprites >> 8
-; ld [rDMA], a
-; ld a, $28
-; .loop
-; dec a
-; jr nz, .loop
-; ret
-
-.vblankoccurred
-; tell other fns vblank happened
+.done
+
xor a
ld [VBlankOccurred], a
-
-; save int flag
+
ld a, [rIF]
push af
-; reset ints
xor a
ld [rIF], a
-; force lcdstat int during sound update
ld a, %10 ; lcd stat
ld [rIE], a
ld [rIF], a
-
+
ei
-; update sound
ld a, BANK(_UpdateSound)
- rst Bankswitch ; bankswitch
+ rst Bankswitch
call _UpdateSound
-; restore bank
- ld a, [$ff8a]
+ ld a, [hROMBankBackup]
rst Bankswitch
di
-
-; request lcdstat
+
+ ; request lcdstat
ld a, [rIF]
ld b, a
-; and any other ints
+ ; and any other ints
pop af
or b
ld b, a
-; reset ints
+ ; reset ints
xor a
ld [rIF], a
-; enable ints besides joypad
+ ; enable ints besides joypad
ld a, %1111 ; serial timer lcdstat vblank
ld [rIE], a
-; request ints
+ ; request ints
ld a, b
ld [rIF], a
ret
@@ -405,40 +332,26 @@ VBlank4:: ; 3df
; serial
; sound
-; save bank
ld a, [hROMBank]
- ld [$ff8a], a
-
+ ld [hROMBankBackup], a
+
call UpdateBGMap
call Serve2bppRequest
-
-; update oam by dma transfer
+
call hPushOAM
-; @PushOAM:
-; ld a, Sprites >> 8
-; ld [rDMA], a
-; ld a, $28
-; .loop
-; dec a
-; jr nz, .loop
-; ret
-
-; update joypad
+
call Joypad
-
-; tell other fns vblank happened
+
xor a
ld [VBlankOccurred], a
-
-; handshake
+
call AskSerial
-
-; update sound
+
ld a, BANK(_UpdateSound)
- rst Bankswitch ; bankswitch
+ rst Bankswitch
call _UpdateSound
-; restore bank
- ld a, [$ff8a]
+
+ ld a, [hROMBankBackup]
rst Bankswitch
ret
; 400
@@ -452,52 +365,42 @@ VBlank5:: ; 400
; joypad
;
-; save bank
ld a, [hROMBank]
- ld [$ff8a], a
-
-; scroll x
+ ld [hROMBankBackup], a
+
ld a, [hSCX]
ld [rSCX], a
-
-; if we can update pals, skip this part
+
call UpdatePalsIfCGB
- jr c, .vblankoccurred
-
+ jr c, .done
+
call UpdateBGMap
call Serve2bppRequest
-
-.vblankoccurred
-; tell other fns vblank happened
+.done
+
xor a
ld [VBlankOccurred], a
-
-; joypad
+
call Joypad
-
-; discard requested ints
+
xor a
ld [rIF], a
-; enable lcd stat
ld a, %10 ; lcd stat
ld [rIE], a
-; request lcd stat
+ ; request lcd stat
ld [rIF], a
-
+
ei
-; update sound
ld a, BANK(_UpdateSound)
- rst Bankswitch ; bankswitch
+ rst Bankswitch
call _UpdateSound
-; restore bank
- ld a, [$ff8a]
+ ld a, [hROMBankBackup]
rst Bankswitch
di
-
-; discard requested ints
+
xor a
ld [rIF], a
-; enable ints besides joypad
+ ; enable ints besides joypad
ld a, %1111 ; serial timer lcdstat vblank
ld [rIE], a
ret
@@ -510,32 +413,29 @@ VBlank6:: ; 436
; dma transfer
; sound
-; save bank
ld a, [hROMBank]
- ld [$ff8a], a
-
-; inc frame counter
+ ld [hROMBankBackup], a
+
+ ; inc frame counter
ld hl, $ff9b
inc [hl]
-
+
call UpdateCGBPals
- jr c, .vblankoccurred
-
+ jr c, .done
+
call Serve2bppRequest
call Serve1bppRequest
call DMATransfer
-
-.vblankoccurred
-; tell other fns vblank happened
+.done
+
xor a
ld [VBlankOccurred], a
-
-; update sound
+
ld a, BANK(_UpdateSound)
- rst Bankswitch ; bankswitch
+ rst Bankswitch
call _UpdateSound
-; restore bank
- ld a, [$ff8a]
+
+ ld a, [hROMBankBackup]
rst Bankswitch
ret
; 45a
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