pokecrystal-board/audio/engine.asm

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NASM
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; The entire sound engine. Uses section "audio" in WRAM.
; Interfaces are in bank 0.
; Notable functions:
; FadeMusic
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; PlayStereoSFX
; PlayCry
_SoundRestart:: ; e8000
; restart sound operation
; clear all relevant hardware registers & wram
push hl
push de
push bc
push af
call MusicOff
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ld hl, rNR50 ; channel control registers
xor a
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ld [hli], a ; rNR50 ; volume/vin
ld [hli], a ; rNR51 ; sfx channels
ld a, $80 ; all channels on
ld [hli], a ; ff26 ; music channels
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ld hl, rNR10 ; sound channel registers
ld e, $04 ; number of channels
.clearsound
; sound channel 1 2 3 4
xor a
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ld [hli], a ; rNR10, $ff15, rNR30, $ff1f ; sweep = 0
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ld [hli], a ; rNR11, rNR21, rNR31, rNR41 ; length/wavepattern = 0
ld a, $08
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ld [hli], a ; rNR12, rNR22, rNR32, rNR42 ; envelope = 0
xor a
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ld [hli], a ; rNR13, rNR23, rNR33, rNR43 ; frequency lo = 0
ld a, $80
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ld [hli], a ; rNR14, rNR24, rNR34, rNR44 ; restart sound (freq hi = 0)
dec e
jr nz, .clearsound
ld hl, Channel1 ; start of channel data
ld de, $01bf ; length of area to clear (entire sound wram area)
.clearchannels ; clear $c101-$c2bf
xor a
ld [hli], a
dec de
ld a, e
or d
jr nz, .clearchannels
ld a, $77 ; max
ld [Volume], a
call MusicOn
pop af
pop bc
pop de
pop hl
ret
; e803d
MusicFadeRestart: ; e803d
; restart but keep the music id to fade in to
ld a, [MusicFadeIDHi]
push af
ld a, [MusicFadeIDLo]
push af
call _SoundRestart
pop af
ld [MusicFadeIDLo], a
pop af
ld [MusicFadeIDHi], a
ret
; e8051
MusicOn: ; e8051
ld a, $01
ld [MusicPlaying], a
ret
; e8057
MusicOff: ; e8057
xor a
ld [MusicPlaying], a
ret
; e805c
_UpdateSound:: ; e805c
; called once per frame
; no use updating audio if it's not playing
ld a, [MusicPlaying]
and a
ret z
; start at ch1
xor a
ld [CurChannel], a ; just
ld [SoundOutput], a ; off
ld bc, Channel1
.loop
; is the channel active?
ld hl, Channel1Flags - Channel1
add hl, bc
bit 0, [hl]
jp z, .nextchannel
; check time left in the current note
ld hl, Channel1NoteDuration - Channel1
add hl, bc
ld a, [hl]
cp a, $02 ; 1 or 0?
jr c, .noteover
dec [hl]
jr .asm_e8093
.noteover
; reset vibrato delay
ld hl, Channel1VibratoDelay - Channel1
add hl, bc
ld a, [hl]
ld hl, Channel1VibratoDelayCount - Channel1
add hl, bc
ld [hl], a
; turn vibrato off for now
ld hl, Channel1Flags2 - Channel1
add hl, bc
res 1, [hl]
; get next note
call ParseMusic
.asm_e8093
;
call Functione84f9
; duty cycle
ld hl, Channel1DutyCycle - Channel1
add hl, bc
ld a, [hli]
ld [$c292], a
; intensity
ld a, [hli]
ld [$c293], a
; frequency
ld a, [hli]
ld [$c294], a
ld a, [hl]
ld [$c295], a
;
call Functione8466 ; handle vibrato and other things
call HandleNoise
; turn off music when playing sfx?
ld a, [SFXPriority]
and a
jr z, .next
; are we in a sfx channel right now?
ld a, [CurChannel]
cp a, $04
jr nc, .next
; are any sfx channels active?
; if so, mute
ld hl, $c1cc ; Channel5Flags
bit 0, [hl]
jr nz, .restnote
ld hl, $c1fe ; Channel6Flags
bit 0, [hl]
jr nz, .restnote
ld hl, $c230 ; Channel7Flags
bit 0, [hl]
jr nz, .restnote
ld hl, $c262 ; Channel8Flags
bit 0, [hl]
jr z, .next
.restnote
ld hl, Channel1NoteFlags - Channel1
add hl, bc
set 5, [hl] ; Rest
.next
; are we in a sfx channel right now?
ld a, [CurChannel]
cp a, $04 ; sfx
jr nc, .asm_e80ee
ld hl, $00cb
add hl, bc
bit 0, [hl]
jr nz, .asm_e80fc
.asm_e80ee
call UpdateChannels
ld hl, Channel1Tracks - Channel1
add hl, bc
ld a, [SoundOutput]
or [hl]
ld [SoundOutput], a
.asm_e80fc
; clear note flags
ld hl, Channel1NoteFlags - Channel1
add hl, bc
xor a
ld [hl], a
.nextchannel
; next channel
ld hl, Channel2 - Channel1
add hl, bc
ld c, l
ld b, h
ld a, [CurChannel]
inc a
ld [CurChannel], a
cp a, $08 ; are we done?
jp nz, .loop ; do it all again
; writing to hardware registers?
call Functione8307
; fade music in/out
call FadeMusic
; write volume to hardware register
ld a, [Volume]
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ld [rNR50], a
; write SO on/off to hardware register
ld a, [SoundOutput]
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ld [rNR51], a
ret
; e8125
UpdateChannels: ; e8125
ld hl, .ChannelFnPtrs
ld a, [CurChannel]
and a, $07
add a
ld e, a
ld d, $00
add hl, de
ld a, [hli]
ld h, [hl]
ld l, a
jp [hl]
.ChannelFnPtrs
dw .Channel1
dw .Channel2
dw .Channel3
dw .Channel4
; sfx ch ptrs are identical to music chs
; ..except 5
dw .Channel5
dw .Channel6
dw .Channel7
dw .Channel8
.Channel1
ld a, [$c2a6]
bit 7, a
ret nz
.Channel5
ld hl, Channel1NoteFlags - Channel1
add hl, bc
bit 3, [hl]
jr z, .asm_e8159
;
ld a, [SoundInput]
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ld [rNR10], a
.asm_e8159
bit 5, [hl] ; rest
jr nz, .ch1rest
bit 4, [hl]
jr nz, .asm_e81a2
bit 1, [hl]
jr nz, .asm_e816b
bit 6, [hl]
jr nz, .asm_e8184
jr .asm_e8175
.asm_e816b
ld a, [$c294]
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ld [rNR13], a
ld a, [$c295]
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ld [rNR14], a
.asm_e8175
bit 0, [hl]
ret z
ld a, [$c292]
ld d, a
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ld a, [rNR11]
and a, $3f ; sound length
or d
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ld [rNR11], a
ret
.asm_e8184
ld a, [$c292]
ld d, a
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ld a, [rNR11]
and a, $3f ; sound length
or d
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ld [rNR11], a
ld a, [$c294]
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ld [rNR13], a
ret
.ch1rest
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ld a, [rNR52]
and a, %10001110 ; ch1 off
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ld [rNR52], a
ld hl, rNR10
call ClearChannel
ret
.asm_e81a2
ld hl, $c292
ld a, $3f ; sound length
or [hl]
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ld [rNR11], a
ld a, [$c293]
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ld [rNR12], a
ld a, [$c294]
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ld [rNR13], a
ld a, [$c295]
or a, $80
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ld [rNR14], a
ret
.Channel2
.Channel6
ld hl, Channel1NoteFlags - Channel1
add hl, bc
bit 5, [hl] ; rest
jr nz, .ch2rest
bit 4, [hl]
jr nz, .asm_e8204
bit 6, [hl]
jr nz, .asm_e81e6
bit 0, [hl]
ret z
ld a, [$c292]
ld d, a
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ld a, [rNR21]
and a, $3f ; sound length
or d
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ld [rNR21], a
ret
.asm_e81db ; unused
ld a, [$c294]
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ld [rNR23], a
ld a, [$c295]
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ld [rNR24], a
ret
.asm_e81e6
ld a, [$c292]
ld d, a
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ld a, [rNR21]
and a, $3f ; sound length
or d
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ld [rNR21], a
ld a, [$c294]
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ld [rNR23], a
ret
.ch2rest
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ld a, [rNR52]
and a, %10001101 ; ch2 off
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ld [rNR52], a
ld hl, $ff15
call ClearChannel
ret
.asm_e8204
ld hl, $c292
ld a, $3f ; sound length
or [hl]
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ld [rNR21], a
ld a, [$c293]
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ld [rNR22], a
ld a, [$c294]
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ld [rNR23], a
ld a, [$c295]
or a, $80 ; initial (restart)
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ld [rNR24], a
ret
.Channel3
.Channel7
ld hl, Channel1NoteFlags - Channel1
add hl, bc
bit 5, [hl] ; rest
jr nz, .ch3rest
bit 4, [hl]
jr nz, .asm_e824d
bit 6, [hl]
jr nz, .asm_e823a
ret
.asm_e822f ; unused
ld a, [$c294]
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ld [rNR33], a
ld a, [$c295]
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ld [rNR34], a
ret
.asm_e823a
ld a, [$c294]
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ld [rNR33], a
ret
.ch3rest
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ld a, [rNR52]
and a, %10001011 ; ch3 off
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ld [rNR52], a
ld hl, rNR30
call ClearChannel
ret
.asm_e824d
ld a, $3f
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ld [rNR31], a
xor a
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ld [rNR30], a
call .asm_e8268
ld a, $80
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ld [rNR30], a
ld a, [$c294]
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ld [rNR33], a
ld a, [$c295]
or a, $80
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ld [rNR34], a
ret
.asm_e8268
push hl
ld a, [$c293]
and a, $0f ; only 0-9 are valid
ld l, a
ld h, $00
; hl << 4
; each wavepattern is $0f bytes long
; so seeking is done in $10s
add hl, hl
add hl, hl
add hl, hl
add hl, hl
ld de, WaveSamples
add hl, de
; load wavepattern into $ff30-$ff3f
ld a, [hli]
ld [$ff30], a
ld a, [hli]
ld [$ff31], a
ld a, [hli]
ld [$ff32], a
ld a, [hli]
ld [$ff33], a
ld a, [hli]
ld [$ff34], a
ld a, [hli]
ld [$ff35], a
ld a, [hli]
ld [$ff36], a
ld a, [hli]
ld [$ff37], a
ld a, [hli]
ld [$ff38], a
ld a, [hli]
ld [$ff39], a
ld a, [hli]
ld [$ff3a], a
ld a, [hli]
ld [$ff3b], a
ld a, [hli]
ld [$ff3c], a
ld a, [hli]
ld [$ff3d], a
ld a, [hli]
ld [$ff3e], a
ld a, [hli]
ld [$ff3f], a
pop hl
ld a, [$c293]
and a, $f0
sla a
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ld [rNR32], a
ret
.Channel4
.Channel8
ld hl, Channel1NoteFlags - Channel1
add hl, bc
bit 5, [hl] ; rest
jr nz, .ch4rest
bit 4, [hl]
jr nz, .asm_e82d4
ret
.asm_e82c1 ; unused
ld a, [$c294]
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ld [rNR43], a
ret
.ch4rest
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ld a, [rNR52]
and a, %10000111 ; ch4 off
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ld [rNR52], a
ld hl, $ff1f
call ClearChannel
ret
.asm_e82d4
ld a, $3f ; sound length
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ld [rNR41], a
ld a, [$c293]
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ld [rNR42], a
ld a, [$c294]
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ld [rNR43], a
ld a, $80
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ld [rNR44], a
ret
; e82e7
_CheckSFX: ; e82e7
; return carry if any sfx channels are active
ld hl, $c1cc ; Channel5Flags
bit 0, [hl]
jr nz, .sfxon
ld hl, $c1fe ; Channel6Flags
bit 0, [hl]
jr nz, .sfxon
ld hl, $c230 ; Channel7Flags
bit 0, [hl]
jr nz, .sfxon
ld hl, $c262 ; Channel8Flags
bit 0, [hl]
jr nz, .sfxon
and a
ret
.sfxon
scf
ret
; e8307
Functione8307: ; e8307
; what is $c2a6?
ld a, [$c2a6]
bit 7, a
ret z
and a, $7f
ld d, a
call _CheckSFX
jr c, .asm_e8335
and a
jr z, .asm_e8323
cp a, $10
jr z, .asm_e831e
jr .asm_e8335
.asm_e831e
ld hl, Tablee8354
jr .updatehw
.asm_e8323
ld hl, Tablee8350
.updatehw
xor a
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ld [rNR10], a ; sweep off
ld a, [hli]
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ld [rNR11], a ; sound length / duty cycle
ld a, [hli]
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ld [rNR12], a ; ch1 volume envelope
ld a, [hli]
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ld [rNR13], a ; ch1 frequency lo
ld a, [hli]
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ld [rNR14], a ; ch1 frequency hi
.asm_e8335
ld a, d
inc a
cp a, $1e
jr c, .asm_e833c
xor a
.asm_e833c
or a, $80
ld [$c2a6], a
; is hw ch1 on?
ld a, [SoundOutput]
and a, $11
ret nz
; if not, turn it on
ld a, [SoundOutput]
or a, $11
ld [SoundOutput], a
ret
; e8350
Tablee8350: ; e8350
db $80 ; duty 50%
db $e2 ; volume $e, envelope decrease sweep 2
db $50 ; frequency: $750
db $87 ; restart sound
; e8354
Tablee8354: ; e8354
db $80 ; duty 50%
db $e2 ; volume $e, envelope decrease sweep 2
db $ee ; frequency: $6ee
db $86 ; restart sound
; e8358
FadeMusic: ; e8358
; fade music if applicable
; usage:
; write to MusicFade
; song fades out at the given rate
; load song id in MusicFadeID
; fade new song in
; notes:
; max # frames per volume level is $3f
; fading?
ld a, [MusicFade]
and a
ret z
; has the count ended?
ld a, [MusicFadeCount]
and a
jr z, .update
; count down
dec a
ld [MusicFadeCount], a
ret
.update
ld a, [MusicFade]
ld d, a
; get new count
and a, $3f
ld [MusicFadeCount], a
; get SO1 volume
ld a, [Volume]
and a, $07
; which way are we fading?
bit 7, d
jr nz, .fadein
; fading out
and a
jr z, .novolume
dec a
jr .updatevolume
.novolume
; make sure volume is off
xor a
ld [Volume], a
; did we just get on a bike?
ld a, [PlayerState]
cp a, $01 ; bicycle
jr z, .bicycle
push bc
; restart sound
call MusicFadeRestart
; get new song id
ld a, [MusicFadeIDLo]
and a
jr z, .quit ; this assumes there are fewer than 256 songs!
ld e, a
ld a, [MusicFadeIDHi]
ld d, a
; load new song
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call _PlayMusic
.quit
; cleanup
pop bc
; stop fading
xor a
ld [MusicFade], a
ret
.bicycle
push bc
; restart sound
call MusicFadeRestart
; this turns the volume up
; turn it back down
xor a
ld [Volume], a
; get new song id
ld a, [MusicFadeIDLo]
ld e, a
ld a, [MusicFadeIDHi]
ld d, a
; load new song
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call _PlayMusic
pop bc
; fade in
ld hl, MusicFade
set 7, [hl]
ret
.fadein
; are we done?
cp a, $07
jr nc, .maxvolume
; inc volume
inc a
jr .updatevolume
.maxvolume
; we're done
xor a
ld [MusicFade], a
ret
.updatevolume
; hi = lo
ld d, a
swap a
or d
ld [Volume], a
ret
; e83d1
LoadNote: ; e83d1
; check mute??
ld hl, Channel1Flags2 - Channel1
add hl, bc
bit 1, [hl]
ret z
; get note duration
ld hl, Channel1NoteDuration - Channel1
add hl, bc
ld a, [hl]
ld hl, $c297 ; ????
sub [hl]
jr nc, .ok
ld a, $01
.ok
ld [hl], a
; get frequency
ld hl, Channel1Frequency - Channel1
add hl, bc
ld e, [hl]
inc hl
ld d, [hl]
; ????
ld hl, $0021
add hl, bc
ld a, e
sub [hl]
ld e, a
ld a, d
sbc a, $00
ld d, a
; ????
ld hl, $0022
add hl, bc
sub [hl]
jr nc, .asm_e8420
; ????
ld hl, Channel1Flags3 - Channel1
add hl, bc
set 1, [hl]
; get frequency
ld hl, Channel1Frequency - Channel1
add hl, bc
ld e, [hl]
inc hl
ld d, [hl]
; ????
ld hl, $0021
add hl, bc
ld a, [hl]
sub e
ld e, a
ld a, d
sbc a, $00
ld d, a
; ????
ld hl, $0022
add hl, bc
ld a, [hl]
sub d
ld d, a
jr .asm_e843e
.asm_e8420
; ????
ld hl, Channel1Flags3 - Channel1
add hl, bc
res 1, [hl]
; get frequency
ld hl, Channel1Frequency - Channel1
add hl, bc
ld e, [hl]
inc hl
ld d, [hl]
; ????
ld hl, $0021
add hl, bc
ld a, e
sub [hl]
ld e, a
ld a, d
sbc a, $00
ld d, a
; ????
ld hl, $0022
add hl, bc
sub [hl]
ld d, a
.asm_e843e
push bc
ld hl, $c297
ld b, $00 ; loop count
.loop
inc b
ld a, e
sub [hl]
ld e, a
jr nc, .loop
ld a, d
and a
jr z, .quit
dec d
jr .loop
.quit
ld a, e ; result
add [hl]
ld d, b ; loop count
; ????
pop bc
ld hl, $0023
add hl, bc
ld [hl], d
ld hl, $0024
add hl, bc
ld [hl], a
; clear ????
ld hl, $0025
add hl, bc
xor a
ld [hl], a
ret
; e8466
Functione8466: ; e8466
; handle vibrato and other things
; unknowns: $c292, $c294
ld hl, Channel1Flags2 - Channel1
add hl, bc
bit 2, [hl]
jr z, .next
ld hl, $001c
add hl, bc
ld a, [hl]
rlca
rlca
ld [hl], a
and a, $c0
ld [$c292], a
ld hl, Channel1NoteFlags - Channel1
add hl, bc
set 0, [hl]
.next
ld hl, Channel1Flags2 - Channel1
add hl, bc
bit 4, [hl]
jr z, .vibrato
ld hl, $0027
add hl, bc
ld e, [hl]
inc hl
ld d, [hl]
ld hl, $c294
ld a, [hli]
ld h, [hl]
ld l, a
add hl, de
ld e, l
ld d, h
ld hl, $c294
ld [hl], e
inc hl
ld [hl], d
.vibrato
; is vibrato on?
ld hl, Channel1Flags2 - Channel1
add hl, bc
bit 0, [hl] ; vibrato
jr z, .quit
; is vibrato active for this note yet?
; is the delay over?
ld hl, Channel1VibratoDelayCount - Channel1
add hl, bc
ld a, [hl]
and a
jr nz, .subexit
; is the extent nonzero?
ld hl, Channel1VibratoExtent - Channel1
add hl, bc
ld a, [hl]
and a
jr z, .quit
; save it for later
ld d, a
; is it time to toggle vibrato up/down?
ld hl, Channel1VibratoRate - Channel1
add hl, bc
ld a, [hl]
and a, $0f ; count
jr z, .toggle
.subexit
dec [hl]
jr .quit
.toggle
; refresh count
ld a, [hl]
swap [hl]
or [hl]
ld [hl], a
; ????
ld a, [$c294]
ld e, a
; toggle vibrato up/down
ld hl, Channel1Flags3 - Channel1
add hl, bc
bit 0, [hl] ; vibrato up/down
jr z, .down
; up
; vibrato down
res 0, [hl]
; get the delay
ld a, d
and a, $0f ; lo
;
ld d, a
ld a, e
sub d
jr nc, .asm_e84ef
ld a, $00
jr .asm_e84ef
.down
; vibrato up
set 0, [hl]
; get the delay
ld a, d
and a, $f0 ; hi
swap a ; move it to lo
;
add e
jr nc, .asm_e84ef
ld a, $ff
.asm_e84ef
ld [$c294], a
;
ld hl, Channel1NoteFlags - Channel1
add hl, bc
set 6, [hl]
.quit
ret
; e84f9
Functione84f9: ; e84f9
; quit if ????
ld hl, Channel1Flags2 - Channel1
add hl, bc
bit 1, [hl]
ret z
; de = Frequency
ld hl, Channel1Frequency - Channel1
add hl, bc
ld e, [hl]
inc hl
ld d, [hl]
;
ld hl, Channel1Flags3 - Channel1
add hl, bc
bit 1, [hl]
jr z, .next
;
ld hl, $0023
add hl, bc
ld l, [hl]
ld h, $00
add hl, de
ld d, h
ld e, l
; get ????
ld hl, $0024
add hl, bc
ld a, [hl]
; add it to ????
ld hl, $0025
add hl, bc
add [hl]
ld [hl], a
ld a, $00
adc e
ld e, a
ld a, $00
adc d
ld d, a
;
ld hl, $0022
add hl, bc
ld a, [hl]
cp d
jp c, .quit1
jr nz, .quit2
ld hl, $0021
add hl, bc
ld a, [hl]
cp e
jp c, .quit1
jr .quit2
.next
ld a, e
ld hl, $0023
add hl, bc
ld e, [hl]
sub e
ld e, a
ld a, d
sbc a, $00
ld d, a
ld hl, $0024
add hl, bc
ld a, [hl]
add a
ld [hl], a
ld a, e
sbc a, $00
ld e, a
ld a, d
sbc a, $00
ld d,a
ld hl, $0022
add hl, bc
ld a, d
cp [hl]
jr c, .quit1
jr nz, .quit2
ld hl, $0021
add hl, bc
ld a, e
cp [hl]
jr nc, .quit2
.quit1
ld hl, Channel1Flags2 - Channel1
add hl, bc
res 1, [hl]
ld hl, Channel1Flags3 - Channel1
add hl, bc
res 1, [hl]
ret
.quit2
ld hl, Channel1Frequency - Channel1
add hl, bc
ld [hl], e
inc hl
ld [hl], d
ld hl, Channel1NoteFlags - Channel1
add hl, bc
set 1, [hl]
set 0, [hl]
ret
; e858c
HandleNoise: ; e858c
; is noise sampling on?
ld hl, Channel1Flags - Channel1
add hl, bc
bit 4, [hl] ; noise sampling
ret z
; are we in a sfx channel?
ld a, [CurChannel]
bit 2, a ; sfx
jr nz, .next
; is ch8 on? (noise)
ld hl, $c262 ; Channel8Flags
bit 0, [hl] ; on?
jr z, .next
; is ch8 playing noise?
bit 4, [hl]
ret nz ; quit if so
;
.next
ld a, [$c2a2]
and a
jr z, ReadNoiseSample
dec a
ld [$c2a2], a
ret
; e85af
ReadNoiseSample: ; e85af
; sample struct:
; [wx] [yy] [zz]
; w: ? either 2 or 3
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; x: duration
; zz: intensity
; yy: frequency
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; de = [NoiseSampleAddress]
ld hl, NoiseSampleAddress
ld e, [hl]
inc hl
ld d, [hl]
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; is it empty?
ld a, e
or d
jr z, .quit
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ld a, [de]
inc de
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cp $ff
jr z, .quit
2013-11-05 12:04:26 -08:00
and $f
inc a
ld [$c2a2], a
ld a, [de]
inc de
ld [$c293], a
ld a, [de]
inc de
ld [$c294], a
xor a
ld [$c295], a
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ld hl, NoiseSampleAddress
ld [hl], e
inc hl
ld [hl], d
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ld hl, Channel1NoteFlags - Channel1
add hl, bc
set 4, [hl]
ret
.quit
ret
; e85e1
ParseMusic: ; e85e1
; parses until a note is read or the song is ended
call GetMusicByte ; store next byte in a
cp a, $ff ; is the song over?
jr z, .readff
cp a, $d0 ; is it a note?
jr c, .readnote
; then it's a command
.readcommand
call ParseMusicCommand
jr ParseMusic ; start over
.readnote
; CurMusicByte contains current note
; special notes
ld hl, Channel1Flags - Channel1
add hl, bc
bit 3, [hl]
jp nz, Functione8698
bit 5, [hl]
jp nz, Functione8698
bit 4, [hl] ; noise sample
jp nz, GetNoiseSample
; normal note
; set note duration (bottom nybble)
ld a, [CurMusicByte]
and a, $0f
call SetNoteDuration
; get note pitch (top nybble)
ld a, [CurMusicByte]
swap a
and a, $0f
jr z, .rest ; pitch $0 -> rest
; update pitch
ld hl, Channel1Pitch - Channel1
add hl, bc
ld [hl], a
; store pitch in e
ld e, a
; store octave in d
ld hl, Channel1Octave - Channel1
add hl, bc
ld d, [hl]
; update frequency
call GetFrequency
ld hl, Channel1Frequency - Channel1
add hl, bc
ld [hl], e
inc hl
ld [hl], d
; ????
ld hl, Channel1NoteFlags - Channel1
add hl, bc
set 4, [hl]
jp LoadNote
.rest
; note = rest
ld hl, Channel1NoteFlags - Channel1
add hl, bc
set 5, [hl] ; Rest
ret
;
.readff
; $ff is reached in music data
ld hl, Channel1Flags - Channel1
add hl, bc
bit 1, [hl] ; in a subroutine?
jr nz, .readcommand ; execute
ld a, [CurChannel]
cp a, $04 ; channels 0-3?
jr nc, .asm_e8651
; ????
ld hl, $00cb
add hl, bc
bit 0, [hl]
jr nz, .ok
.asm_e8651
ld hl, Channel1Flags - Channel1
add hl, bc
bit 5, [hl]
call nz, RestoreVolume
; end music
ld a, [CurChannel]
cp a, $04 ; channel 5?
jr nz, .ok
; ????
xor a
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ld [rNR10], a ; sweep = 0
.ok
; stop playing
; turn channel off
ld hl, Channel1Flags - Channel1
add hl, bc
res 0, [hl]
; note = rest
ld hl, Channel1NoteFlags - Channel1
add hl, bc
set 5, [hl]
; clear music id & bank
ld hl, Channel1MusicID - Channel1
add hl, bc
xor a
ld [hli], a ; id hi
ld [hli], a ; id lo
ld [hli], a ; bank
ret
; e8679
RestoreVolume: ; e8679
; ch5 only
ld a, [CurChannel]
cp a, $04
ret nz
xor a
ld hl, $c222
ld [hli], a
ld [hl], a
ld hl, $c286
ld [hli], a
ld [hl], a
ld a, [LastVolume]
ld [Volume], a
xor a
ld [LastVolume], a
ld [SFXPriority], a
ret
; e8698
Functione8698: ; e8698
; turn noise sampling on
ld hl, Channel1NoteFlags - Channel1
add hl, bc
set 4, [hl] ; noise sample
; update note duration
ld a, [CurMusicByte]
call SetNoteDuration ; top nybble doesnt matter?
; update intensity from next param
call GetMusicByte
ld hl, Channel1Intensity - Channel1
add hl, bc
ld [hl], a
; update lo frequency from next param
call GetMusicByte
ld hl, Channel1FrequencyLo - Channel1
add hl, bc
ld [hl], a
; are we on the last channel? (noise sampling)
ld a, [CurChannel]
and a, $03
cp a, $03
ret z
; update hi frequency from next param
call GetMusicByte
ld hl, Channel1FrequencyHi - Channel1
add hl, bc
ld [hl], a
ret
; e86c5
GetNoiseSample: ; e86c5
; load ptr to sample header in NoiseSampleAddress
; are we on the last channel?
ld a, [CurChannel]
and a, $03
cp a, $03
; ret if not
ret nz
; update note duration
ld a, [CurMusicByte]
and a, $0f
call SetNoteDuration
; check current channel
ld a, [CurChannel]
bit 2, a ; are we in a sfx channel?
jr nz, .sfx
ld hl, $c262 ; Channel8Flags
bit 0, [hl] ; is ch8 on? (noise)
ret nz
ld a, [MusicNoiseSampleSet]
jr .next
.sfx
ld a, [SFXNoiseSampleSet]
.next
; load noise sample set id into de
ld e, a
ld d, $00
; load ptr to noise sample set in hl
ld hl, NoiseSampleSetsPointers
add hl, de
add hl, de
ld a, [hli]
ld h, [hl]
ld l, a
; get pitch
ld a, [CurMusicByte]
swap a
; non-rest note?
and a, $0f
ret z
; use 'pitch' to seek noise sample set
ld e, a
ld d, $00
add hl, de
add hl, de
; load sample pointer into NoiseSampleAddress
ld a, [hli]
ld [NoiseSampleAddressLo], a
ld a, [hl]
ld [NoiseSampleAddressHi], a
; clear ????
xor a
ld [$c2a2], a
ret
; e870f
ParseMusicCommand: ; e870f
; reload command
ld a, [CurMusicByte]
; get command #
sub a, $d0 ; first command
ld e, a
ld d, $00
; seek command pointer
ld hl, MusicCommands
add hl, de
add hl, de
; jump to the new pointer
ld a, [hli]
ld h, [hl]
ld l, a
jp [hl]
; e8720
MusicCommands: ; e8720
; pointer to each command in order
; octaves
dw MusicD0 ; octave 8
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dw MusicD1 ; octave 7
dw MusicD2 ; octave 6
dw MusicD3 ; octave 5
dw MusicD4 ; octave 4
dw MusicD5 ; octave 3
dw MusicD6 ; octave 2
dw MusicD7 ; octave 1
dw MusicD8 ; note length + intensity
dw MusicD9 ; set starting octave
dw MusicDA ; tempo
dw MusicDB ; duty cycle
dw MusicDC ; intensity
dw MusicDD ; update sound status
dw MusicDE ; ???? + duty cycle
dw MusicDF ;
dw MusicE0 ;
dw MusicE1 ; vibrato
dw MusicE2 ;
dw MusicE3 ; music noise sampling
dw MusicE4 ; force panning
dw MusicE5 ; volume
dw MusicE6 ; tune
dw MusicE7 ;
dw MusicE8 ;
dw MusicE9 ; global tempo
dw MusicEA ; restart current channel from header
dw MusicEB ; new song
dw MusicEC ; sfx priority on
dw MusicED ; sfx priority off
dw MusicEE ;
dw MusicEF ; stereo panning
dw MusicF0 ; sfx noise sampling
dw MusicF1 ; nothing
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dw MusicF2 ; nothing
dw MusicF3 ; nothing
dw MusicF4 ; nothing
dw MusicF5 ; nothing
dw MusicF6 ; nothing
dw MusicF7 ; nothing
dw MusicF8 ; nothing
dw MusicF9 ;
dw MusicFA ;
dw MusicFB ;
dw MusicFC ; jump
dw MusicFD ; loop
dw MusicFE ; call
dw MusicFF ; return
; e8780
MusicF1: ; e8780
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MusicF2: ; e8780
MusicF3: ; e8780
MusicF4: ; e8780
MusicF5: ; e8780
MusicF6: ; e8780
MusicF7: ; e8780
MusicF8: ; e8780
ret
; e8781
MusicFF: ; e8781
; called when $ff is encountered w/ subroutine flag set
; end music stream
; return to caller of the subroutine
; reset subroutine flag
ld hl, Channel1Flags - Channel1
add hl, bc
res 1, [hl]
; copy LastMusicAddress to MusicAddress
ld hl, Channel1LastMusicAddress - Channel1
add hl, bc
ld e, [hl]
inc hl
ld d, [hl]
ld hl, Channel1MusicAddress - Channel1
add hl, bc
ld [hl], e
inc hl
ld [hl], d
ret
; e8796
MusicFE: ; e8796
; call music stream (subroutine)
; parameters: ll hh ; pointer to subroutine
; get pointer from next 2 bytes
call GetMusicByte
ld e, a
call GetMusicByte
ld d, a
push de
; copy MusicAddress to LastMusicAddress
ld hl, Channel1MusicAddress - Channel1
add hl, bc
ld e, [hl]
inc hl
ld d, [hl]
ld hl, Channel1LastMusicAddress - Channel1
add hl, bc
ld [hl], e
inc hl
ld [hl], d
; load pointer into MusicAddress
pop de
ld hl, Channel1MusicAddress - Channel1
add hl, bc
ld [hl], e
inc hl
ld [hl], d
; set subroutine flag
ld hl, Channel1Flags - Channel1
add hl, bc
set 1, [hl]
ret
; e87bc
MusicFC: ; e87bc
; jump
; parameters: ll hh ; pointer
; get pointer from next 2 bytes
call GetMusicByte
ld e, a
call GetMusicByte
ld d, a
ld hl, Channel1MusicAddress - Channel1
add hl, bc
ld [hl], e
inc hl
ld [hl], d
ret
; e87cc
MusicFD: ; e87cc
; loops xx - 1 times
; 00: infinite
; params: 3
; xx ll hh
; xx : loop count
; ll hh : pointer
; get loop count
call GetMusicByte
ld hl, Channel1Flags - Channel1
add hl, bc
bit 2, [hl] ; has the loop been initiated?
jr nz, .checkloop
and a ; loop counter 0 = infinite
jr z, .loop
; initiate loop
dec a
set 2, [hl] ; set loop flag
ld hl, Channel1LoopCount - Channel1
add hl, bc
ld [hl], a ; store loop counter
.checkloop
ld hl, Channel1LoopCount - Channel1
add hl, bc
ld a, [hl]
and a ; are we done?
jr z, .endloop
dec [hl]
.loop
; get pointer
call GetMusicByte
ld e, a
call GetMusicByte
ld d, a
; load new pointer into MusicAddress
ld hl, Channel1MusicAddress - Channel1
add hl, bc
ld [hl], e
inc hl
ld [hl], d
ret
.endloop
; reset loop flag
ld hl, Channel1Flags - Channel1
add hl, bc
res 2, [hl]
; skip to next command
ld hl, Channel1MusicAddress - Channel1
add hl, bc
ld e, [hl]
inc hl
ld d, [hl]
inc de ; skip
inc de ; pointer
ld [hl], d
dec hl
ld [hl], e
ret
; e880e
MusicFA: ; e880e
; set condition for a jump
; used with FB
; params: 1
; xx ; condition
; set condition
call GetMusicByte
ld hl, Channel1Condition - Channel1
add hl, bc
ld [hl], a
ret
; e8817
MusicFB: ; e8817
; conditional jump
; used with FA
; params: 3
; xx: condition
; ll hh: pointer
; check condition
; a = condition
call GetMusicByte
; if existing condition matches, jump to new address
ld hl, Channel1Condition - Channel1
add hl, bc
cp [hl]
jr z, .jump
; skip to next command
; get address
ld hl, Channel1MusicAddress - Channel1
add hl, bc
ld e, [hl]
inc hl
ld d, [hl]
; skip pointer
inc de
inc de
; update address
ld [hl], d
dec hl
ld [hl], e
ret
.jump
; jump to the new address
; get pointer
call GetMusicByte
ld e, a
call GetMusicByte
ld d, a
; update pointer in MusicAddress
ld hl, Channel1MusicAddress - Channel1
add hl, bc
ld [hl], e
inc hl
ld [hl], d
ret
; e883e
MusicEE; e883e
; conditional jump
; checks a byte in ram corresponding to the current channel
; doesn't seem to be set by any commands
; params: 2
; ll hh ; pointer
; if ????, jump
; get channel
ld a, [CurChannel]
and a, $03 ; ch0-3
ld e, a
ld d, $00
; hl = $c2b8 + channel id
ld hl, $c2b8
add hl, de
; if set, jump
ld a, [hl]
and a
jr nz, .jump
; skip to next command
; get address
ld hl, Channel1MusicAddress - Channel1
add hl, bc
ld e, [hl]
inc hl
ld d, [hl]
; skip pointer
inc de
inc de
; update address
ld [hl], d
dec hl
ld [hl], e
ret
.jump
; reset jump flag
ld [hl], $00
; de = pointer
call GetMusicByte
ld e, a
call GetMusicByte
ld d, a
; update address
ld hl, Channel1MusicAddress - Channel1
add hl, bc
ld [hl], e
inc hl
ld [hl], d
ret
; e886d
MusicF9: ; e886d
; sets some flag
; seems to be unused
; params: 0
ld a, $01
ld [$c2b5], a
ret
; e8873
MusicE2: ; e8873
; seems to have been dummied out
; params: 1
call GetMusicByte
ld hl, $002c
add hl, bc
ld [hl], a
ld hl, Channel1Flags2 - Channel1
add hl, bc
set 3, [hl]
ret
; e8882
MusicE1: ; e8882
; vibrato
; params: 2
; 1: [xx]
; delay in frames
; 2: [yz]
; y: extent
; z: rate (# frames per cycle)
; set vibrato flag?
ld hl, Channel1Flags2 - Channel1
add hl, bc
set 0, [hl]
; start at lower frequency (extent is positive)
ld hl, Channel1Flags3 - Channel1
add hl, bc
res 0, [hl]
; get delay
call GetMusicByte
; update delay
ld hl, Channel1VibratoDelay - Channel1
add hl, bc
ld [hl], a
; update delay count
ld hl, Channel1VibratoDelayCount - Channel1
add hl, bc
ld [hl], a
; update extent
; this is split into halves only to get added back together at the last second
; get extent/rate
call GetMusicByte
ld hl, Channel1VibratoExtent - Channel1
add hl, bc
ld d, a
; get top nybble
and a, $f0
swap a
srl a ; halve
ld e, a
adc a, $00 ; round up
swap a
or e
ld [hl], a
; update rate
ld hl, Channel1VibratoRate - Channel1
add hl, bc
; get bottom nybble
ld a, d
and a, $0f
ld d, a
swap a
or d
ld [hl], a
ret
; e88bd
MusicE0: ; e88bd
; ????
; params: 2
call GetMusicByte
ld [$c297], a
call GetMusicByte
ld d, a
and a, $0f
ld e, a
ld a, d
swap a
and a, $0f
ld d, a
call GetFrequency
ld hl, $0021
add hl, bc
ld [hl], e
ld hl, $0022
add hl, bc
ld [hl], d
ld hl, Channel1Flags2 - Channel1
add hl, bc
set 1, [hl]
ret
; e88e4
MusicE6: ; e88e4
; tone
; params: 2
ld hl, Channel1Flags2 - Channel1
add hl, bc
set 4, [hl]
ld hl, $0028
add hl, bc
call GetMusicByte
ld [hld], a
call GetMusicByte
ld [hl], a
ret
; e88f7
MusicE7: ; e88f7
; shrug
; params: 1
ld hl, Channel1Flags2 - Channel1
add hl, bc
set 6, [hl]
call GetMusicByte
ld hl, $0029
add hl, bc
ld [hl], a
ret
; e8906
MusicDE: ; e8906
; ???? + duty cycle
; params: 1
;
ld hl, Channel1Flags2 - Channel1
add hl, bc
set 2, [hl] ; duty cycle
;
call GetMusicByte
rrca
rrca
ld hl, $001c
add hl, bc
ld [hl], a
; update duty cycle
and a, $c0 ; only uses top 2 bits
ld hl, Channel1DutyCycle - Channel1
add hl, bc
ld [hl], a
ret
; e891e
MusicE8: ; e891e
; shrug
; params: 1
ld hl, Channel1Flags2 - Channel1
add hl, bc
set 5, [hl]
call GetMusicByte
ld hl, $002a
add hl, bc
ld [hl], a
ret
; e892d
MusicDF: ; e892d
; toggle something
; params: none
ld hl, Channel1Flags - Channel1
add hl, bc
bit 3, [hl]
jr z, .on
res 3, [hl]
ret
.on
set 3, [hl]
ret
; e893b
MusicE3: ; e893b
; toggle music noise sampling
; can't be used as a straight toggle since the param is not read from on->off
; params:
; noise on: 1
; noise off: 0
; check if noise sampling is on
ld hl, Channel1Flags - Channel1
add hl, bc
bit 4, [hl]
jr z, .on
; turn noise sampling off
res 4, [hl]
ret
.on
; turn noise sampling on
set 4, [hl]
call GetMusicByte
ld [MusicNoiseSampleSet], a
ret
; e894f
MusicF0: ; e894f
; toggle sfx noise sampling
; params:
; on: 1
; off: 0
; check if noise sampling is on
ld hl, Channel1Flags - Channel1
add hl, bc
bit 4, [hl]
jr z, .on
; turn noise sampling off
res 4, [hl]
ret
.on
; turn noise sampling on
set 4, [hl]
call GetMusicByte
ld [SFXNoiseSampleSet], a
ret
; e8963
MusicD8: ; e8963
; note length
; # frames per 16th note
; intensity: see MusicDC
; params: 2
; note length
call GetMusicByte
ld hl, $002d
add hl, bc
ld [hl], a
ld a, [CurChannel]
and a, $03
cp a, $03
ret z
; intensity
call MusicDC
ret
; e8977
MusicDD: ; e8977
; update sound status
; params: 1
call GetMusicByte
ld [SoundInput], a
ld hl, Channel1NoteFlags - Channel1
add hl, bc
set 3, [hl]
ret
; e8984
MusicDB: ; e8984
; duty cycle
; params: 1
call GetMusicByte
rrca
rrca
and a, $c0
ld hl, Channel1DutyCycle - Channel1
add hl, bc
ld [hl], a
ret
; e8991
MusicDC: ; e8991
; intensity
; params: 1
; hi: pressure
; lo: velocity
call GetMusicByte
ld hl, Channel1Intensity - Channel1
add hl, bc
ld [hl], a
ret
; e899a
MusicDA: ; e899a
; global tempo
; params: 2
; de: tempo
call GetMusicByte
ld d, a
call GetMusicByte
ld e, a
call SetGlobalTempo
ret
; e89a6
MusicD0: ; e89a6
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MusicD1: ; e89a6
MusicD2: ; e89a6
MusicD3: ; e89a6
MusicD4: ; e89a6
MusicD5: ; e89a6
MusicD6: ; e89a6
MusicD7: ; e89a6
; set octave based on lo nybble of the command
ld hl, Channel1Octave - Channel1
add hl, bc
2013-11-05 12:17:24 -08:00
ld a, [CurMusicByte]
and 7
ld [hl], a
ret
; e89b1
MusicD9: ; e89b1
; set starting octave
; this forces all notes up by the starting octave
; params: 1
call GetMusicByte
ld hl, Channel1StartingOctave - Channel1
add hl, bc
ld [hl], a
ret
; e89ba
MusicEF: ; e89ba
; stereo panning
; params: 1
; stereo on?
ld a, [Options]
bit 5, a ; stereo
jr nz, MusicE4
; skip param
call GetMusicByte
ret
; e89c5
MusicE4: ; e89c5
; force panning
; params: 1
call SetLRTracks
call GetMusicByte
ld hl, Channel1Tracks - Channel1
add hl, bc
and [hl]
ld [hl], a
ret
; e89d2
MusicE5: ; e89d2
; set volume
; params: 1
; see Volume
; read param even if it's not used
call GetMusicByte
; is the song fading?
ld a, [MusicFade]
and a
ret nz
; reload param
ld a, [CurMusicByte]
; set volume
ld [Volume], a
ret
; e89e1
MusicE9: ; e89e1
; set global tempo to current channel tempo +- param
; params: 1 signed
call GetMusicByte
ld e, a
; check sign
cp a, $80
jr nc, .negative
;positive
ld d, $00
jr .ok
.negative
ld d, $ff
.ok
ld hl, Channel1Tempo - Channel1
add hl, bc
ld a, [hli]
ld h, [hl]
ld l, a
add hl, de
ld e, l
ld d, h
call SetGlobalTempo
ret
; e89fd
MusicEC: ; e89fd
; turn sfx priority on
; params: none
ld a, $01
ld [SFXPriority], a
ret
; e8a03
MusicED: ; e8a03
; turn sfx priority off
; params: none
xor a
ld [SFXPriority], a
ret
; e8a08
MusicEA: ; e8a08
; restart current channel from channel header (same bank)
; params: 2 (5)
; ll hh: pointer to new channel header
; header format: 0x yy zz
; x: channel # (0-3)
; zzyy: pointer to new music data
; update music id
ld hl, Channel1MusicID - Channel1
add hl, bc
ld a, [hli]
ld [MusicIDLo], a
ld a, [hl]
ld [MusicIDHi], a
; update music bank
ld hl, Channel1MusicBank - Channel1
add hl, bc
ld a, [hl]
ld [MusicBank], a
; get pointer to new channel header
call GetMusicByte
ld l, a
call GetMusicByte
ld h, a
ld e, [hl]
inc hl
ld d, [hl]
push bc ; save current channel
call LoadChannel
call StartChannel
pop bc ; restore current channel
ret
; e8a30
MusicEB: ; e8a30
; new song
; params: 2
; de: song id
call GetMusicByte
ld e, a
call GetMusicByte
ld d, a
push bc
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call _PlayMusic
pop bc
ret
; e8a3e
GetMusicByte: ; e8a3e
; returns byte from current address in a
; advances to next byte in music data
; input: bc = start of current channel
push hl
push de
; load address into de
ld hl, Channel1MusicAddress - Channel1
add hl, bc
ld a, [hli]
ld e, a
ld d, [hl]
; load bank into a
ld hl, Channel1MusicBank - Channel1
add hl, bc
ld a, [hl]
; get byte
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call _LoadMusicByte ; load data into CurMusicByte
inc de ; advance to next byte for next time this is called
; update channeldata address
ld hl, Channel1MusicAddress - Channel1
add hl, bc
ld a, e
ld [hli], a
ld [hl], d
; cleanup
pop de
pop hl
; store channeldata in a
ld a, [CurMusicByte]
ret
; e8a5d
GetFrequency: ; e8a5d
; generate frequency
; input:
; d: octave
; e: pitch
; output:
; de: frequency
; get octave
; get starting octave
ld hl, Channel1StartingOctave - Channel1
add hl, bc
ld a, [hl]
swap a ; hi nybble
and a, $0f
; add current octave
add d
push af ; we'll use this later
; get starting octave
ld hl, Channel1StartingOctave - Channel1
add hl, bc
ld a, [hl]
and a, $0f ; lo nybble
;
ld l, a ; ok
ld d, $00
ld h, d
add hl, de ; add current pitch
add hl, hl ; skip 2 bytes for each
ld de, FrequencyTable
add hl, de
ld e, [hl]
inc hl
ld d, [hl]
; get our octave
pop af
.loop
; [7 - octave] loops
cp a, $07
jr nc, .ok
; sra de
sra d
rr e
inc a
jr .loop
.ok
ld a, d
and a, $07 ; top 3 bits for frequency (11 total)
ld d, a
ret
; e8a8d
SetNoteDuration: ; e8a8d
; input: a = note duration in 16ths
; store delay units in de
inc a
ld e, a
ld d, $00
; store NoteLength in a
ld hl, Channel1NoteLength - Channel1
add hl, bc
ld a, [hl]
; multiply NoteLength by delay units
ld l, $00 ; just multiply
call MultiplySimple
ld a, l ; % $100
; store Tempo in de
ld hl, Channel1Tempo - Channel1
add hl, bc
ld e, [hl]
inc hl
ld d, [hl]
; add ???? to the next result
ld hl, $0016
add hl, bc
ld l, [hl]
; multiply Tempo by last result (NoteLength * delay % $100)
call MultiplySimple
; copy result to de
ld e, l
ld d, h
; store result in ????
ld hl, $0016
add hl, bc
ld [hl], e
; store result in NoteDuration
ld hl, Channel1NoteDuration - Channel1
add hl, bc
ld [hl], d
ret
; e8ab8
MultiplySimple: ; e8ab8
; multiplies a and de
; adds the result to l
; stores the result in hl
ld h, $00
.loop
; halve a
srl a
; is there a remainder?
jr nc, .skip
; add it to the result
add hl, de
.skip
; add de, de
sla e
rl d
; are we done?
and a
jr nz, .loop
ret
; e8ac7
SetGlobalTempo: ; e8ac7
push bc ; save current channel
; are we dealing with music or sfx?
ld a, [CurChannel]
cp a, $04
jr nc, .sfxchannels
ld bc, Channel1
call SetTempo
ld bc, Channel2
call SetTempo
ld bc, Channel3
call SetTempo
ld bc, Channel4
call SetTempo
jr .end
.sfxchannels
ld bc, Channel5
call SetTempo
ld bc, Channel6
call SetTempo
ld bc, Channel7
call SetTempo
ld bc, Channel8
call SetTempo
.end
pop bc ; restore current channel
ret
; e8b03
SetTempo: ; e8b03
; input:
; de: note length
; update Tempo
ld hl, Channel1Tempo - Channel1
add hl, bc
ld [hl], e
inc hl
ld [hl], d
; clear ????
xor a
ld hl, $0016
add hl, bc
ld [hl], a
ret
; e8b11
StartChannel: ; e8b11
call SetLRTracks
ld hl, Channel1Flags - Channel1
add hl, bc
set 0, [hl] ; turn channel on
ret
; e8b1b
SetLRTracks: ; e8b1b
; set tracks for a the current channel to default
; seems to be redundant since this is overwritten by stereo data later
push de
; store current channel in de
ld a, [CurChannel]
and a, $03
ld e, a
ld d, $00
; get this channel's lr tracks
call GetLRTracks
add hl, de ; de = channel 0-3
ld a, [hl]
; load lr tracks into Tracks
ld hl, Channel1Tracks - Channel1
add hl, bc
ld [hl], a
pop de
ret
; e8b30
_PlayMusic:: ; e8b30
; load music
call MusicOff
ld hl, MusicID
ld [hl], e ; song number
inc hl
ld [hl], d ; MusicIDHi (always $00)
ld hl, Music
add hl, de ; three
add hl, de ; byte
add hl, de ; pointer
ld a, [hli]
ld [MusicBank], a
ld e, [hl]
inc hl
ld d, [hl] ; music header address
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call LoadMusicByte ; store first byte of music header in a
rlca
rlca
and a, $03 ; get number of channels
inc a
.loop
; start playing channels
push af
call LoadChannel
call StartChannel
pop af
dec a
jr nz, .loop
xor a
ld [$c2b5], a
ld [$c2b8], a
ld [$c2b9], a
ld [$c2ba], a
ld [$c2bb], a
ld [NoiseSampleAddressLo], a
ld [NoiseSampleAddressHi], a
ld [$c2a2], a
ld [MusicNoiseSampleSet], a
call MusicOn
ret
; e8b79
PlayCry:: ; e8b79
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; Play cry de using parameters:
; CryPitch
; CryEcho
; CryLength
call MusicOff
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; Overload the music id with the cry id
ld hl, MusicID
ld [hl], e
inc hl
ld [hl], d
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; 3-byte pointers (bank, address)
ld hl, Cries
add hl, de
add hl, de
add hl, de
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ld a, [hli]
ld [MusicBank], a
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ld e, [hl]
inc hl
ld d, [hl]
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; Read the cry's sound header
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call LoadMusicByte
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; Top 2 bits contain the number of channels
rlca
rlca
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and a, 3
; For each channel:
inc a
.loop
push af
call LoadChannel
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ld hl, Channel1Flags - Channel1
add hl, bc
set 5, [hl]
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ld hl, Channel1Flags2 - Channel1
add hl, bc
set 4, [hl]
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ld hl, Channel1CryPitch - Channel1
add hl, bc
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ld a, [CryPitch]
ld [hli], a
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ld a, [CryEcho]
ld [hl], a
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; No tempo for channel 4
ld a, [CurChannel]
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and a, 3
cp 3
jr nc, .start
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; Tempo is effectively length
ld hl, Channel1Tempo - Channel1
add hl, bc
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ld a, [CryLength]
ld [hli], a
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ld a, [CryLength+1]
ld [hl], a
.start
call StartChannel
ld a, [$c2bc]
and a
jr z, .next
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; Stereo only: Play cry from the monster's side.
; This only applies in-battle.
ld a, [Options]
bit 5, a ; stereo
jr z, .next
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; [Tracks] &= [CryTracks]
ld hl, Channel1Tracks - Channel1
add hl, bc
ld a, [hl]
ld hl, CryTracks
and a, [hl]
ld hl, Channel1Tracks - Channel1
add hl, bc
ld [hl], a
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.next
pop af
dec a
jr nz, .loop
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; Cries play at max volume, so we save the current volume for later.
ld a, [LastVolume]
and a
jr nz, .end
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ld a, [Volume]
ld [LastVolume], a
ld a, $77
ld [Volume], a
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.end
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ld a, 1 ; stop playing music
ld [SFXPriority], a
call MusicOn
ret
; e8c04
_PlaySFX:: ; e8c04
; clear channels if they aren't already
call MusicOff
ld hl, $c1cc ; Channel5Flags
bit 0, [hl] ; ch5 on?
jr z, .ch6
res 0, [hl] ; turn it off
xor a
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ld [rNR11], a ; length/wavepattern = 0
ld a, $08
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ld [rNR12], a ; envelope = 0
xor a
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ld [rNR13], a ; frequency lo = 0
ld a, $80
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ld [rNR14], a ; restart sound (freq hi = 0)
xor a
ld [SoundInput], a ; global sound off
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ld [rNR10], a ; sweep = 0
.ch6
ld hl, $c1fe ; ch6 on?
bit 0, [hl]
jr z, .ch7
res 0, [hl] ; turn it off
xor a
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ld [rNR21], a ; length/wavepattern = 0
ld a, $08
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ld [rNR22], a ; envelope = 0
xor a
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ld [rNR23], a ; frequency lo = 0
ld a, $80
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ld [rNR24], a ; restart sound (freq hi = 0)
.ch7
ld hl, $c230 ; ch7 on?
bit 0, [hl]
jr z, .ch8
res 0, [hl] ; turn it off
xor a
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ld [rNR30], a ; sound mode #3 off
ld [rNR31], a ; length/wavepattern = 0
ld a, $08
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ld [rNR32], a ; envelope = 0
xor a
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ld [rNR33], a ; frequency lo = 0
ld a, $80
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ld [rNR34], a ; restart sound (freq hi = 0)
.ch8
ld hl, $c262 ; ch8 on?
bit 0, [hl]
jr z, .chscleared
res 0, [hl] ; turn it off
xor a
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ld [rNR41], a ; length/wavepattern = 0
ld a, $08
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ld [rNR42], a ; envelope = 0
xor a
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ld [rNR43], a ; frequency lo = 0
ld a, $80
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ld [rNR44], a ; restart sound (freq hi = 0)
xor a
ld [NoiseSampleAddressLo], a
ld [NoiseSampleAddressHi], a
.chscleared
; start reading sfx header for # chs
ld hl, MusicID
ld [hl], e
inc hl
ld [hl], d
ld hl, SFX
add hl, de ; three
add hl, de ; byte
add hl, de ; pointers
; get bank
ld a, [hli]
ld [MusicBank], a
; get address
ld e, [hl]
inc hl
ld d, [hl]
; get # channels
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call LoadMusicByte
rlca ; top 2
rlca ; bits
and a, $03
inc a ; # channels -> # loops
.startchannels
push af
call LoadChannel ; bc = current channel
ld hl, Channel1Flags - Channel1
add hl, bc
set 3, [hl]
call StartChannel
pop af
dec a
jr nz, .startchannels
call MusicOn
xor a
ld [SFXPriority], a
ret
; e8ca6
PlayStereoSFX:: ; e8ca6
; play sfx de
call MusicOff
; standard procedure if stereo's off
ld a, [Options]
bit 5, a
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jp z, _PlaySFX
; else, let's go ahead with this
ld hl, MusicID
ld [hl], e
inc hl
ld [hl], d
; get sfx ptr
ld hl, SFX
add hl, de
add hl, de
add hl, de
; bank
ld a, [hli]
ld [MusicBank], a
; address
ld e, [hl]
inc hl
ld d, [hl]
; bit 2-3
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call LoadMusicByte
rlca
rlca
and 3 ; ch1-4
inc a
.loop
push af
call LoadChannel
ld hl, Channel1Flags - Channel1
add hl, bc
set 3, [hl]
push de
; get tracks for this channel
ld a, [CurChannel]
and 3 ; ch1-4
ld e, a
ld d, $0
call GetLRTracks
add hl, de
ld a, [hl]
ld hl, $c2bc
and [hl]
ld hl, Channel1Tracks - Channel1
add hl, bc
ld [hl], a
ld hl, $0030 ; $c131 - Channel1
add hl, bc
ld [hl], a
ld a, [CryTracks]
cp 2 ; ch 1-2
jr c, .asm_e8d0c
; ch3-4
ld a, [$c2be]
ld hl, $002e ; $c12f - Channel1
add hl, bc
ld [hl], a
ld hl, $002f ; $c130 - Channel1
add hl, bc
ld [hl], a
ld hl, Channel1Flags2 - Channel1
add hl, bc
set 7, [hl]
.asm_e8d0c
pop de
; turn channel on
ld hl, Channel1Flags - Channel1
add hl, bc
set 0, [hl] ; on
; done?
pop af
dec a
jr nz, .loop
; we're done
call MusicOn
ret
; e8d1b
LoadChannel: ; e8d1b
; prep channel for use
; input:
; de:
; get pointer to current channel
2013-10-08 10:34:32 -07:00
call LoadMusicByte
inc de
and a, $07 ; bit 0-2 (current channel)
ld [CurChannel], a
ld c, a
ld b, $00
ld hl, ChannelPointers
add hl, bc
add hl, bc
ld c, [hl]
inc hl
ld b, [hl] ; bc = channel pointer
ld hl, Channel1Flags - Channel1
add hl, bc
res 0, [hl] ; channel off
call ChannelInit
; load music pointer
ld hl, Channel1MusicAddress - Channel1
add hl, bc
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call LoadMusicByte
ld [hli], a
inc de
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call LoadMusicByte
ld [hl], a
inc de
; load music id
ld hl, Channel1MusicID - Channel1
add hl, bc
ld a, [MusicIDLo]
ld [hli], a
ld a, [MusicIDHi]
ld [hl], a
; load music bank
ld hl, Channel1MusicBank - Channel1
add hl, bc
ld a, [MusicBank]
ld [hl], a
ret
; e8d5b
ChannelInit: ; e8d5b
; make sure channel is cleared
; set default tempo and note length in case nothing is loaded
; input:
; bc = channel struct pointer
push de
xor a
; get channel struct location and length
ld hl, Channel1MusicID - Channel1 ; start
add hl, bc
ld e, Channel2 - Channel1 ; channel struct length
; clear channel
.loop
ld [hli], a
dec e
jr nz, .loop
; set tempo to default ($100)
ld hl, Channel1Tempo - Channel1
add hl, bc
xor a
ld [hli], a
inc a
ld [hl], a
; set note length to default ($01) (fast)
ld hl, Channel1NoteLength - Channel1
add hl, bc
ld [hl], a
pop de
ret
; e8d76
LoadMusicByte:: ; e8d76
; input:
; de = current music address
; output:
; a = CurMusicByte
ld a, [MusicBank]
2013-10-08 10:34:32 -07:00
call _LoadMusicByte
ld a, [CurMusicByte]
ret
; e8d80
FrequencyTable: ; e8d80
dw $0000 ; filler
dw $f82c
dw $f89d
dw $f907
dw $f96b
dw $f9ca
dw $fa23
dw $fa77
dw $fac7
dw $fb12
dw $fb58
dw $fb9b
dw $fbda
dw $fc16
dw $fc4e
dw $fc83
dw $fcb5
dw $fce5
dw $fd11
dw $fd3b
dw $fd63
dw $fd89
dw $fdac
dw $fdcd
dw $fded
; e8db2
WaveSamples: ; e8db2
; these are streams of 32 4-bit values used as wavepatterns
; nothing interesting here!
db $02, $46, $8a, $ce, $ff, $fe, $ed, $dc, $cb, $a9, $87, $65, $44, $33, $22, $11
db $02, $46, $8a, $ce, $ef, $ff, $fe, $ee, $dd, $cb, $a9, $87, $65, $43, $22, $11
db $13, $69, $bd, $ee, $ee, $ff, $ff, $ed, $de, $ff, $ff, $ee, $ee, $db, $96, $31
db $02, $46, $8a, $cd, $ef, $fe, $de, $ff, $ee, $dc, $ba, $98, $76, $54, $32, $10
db $01, $23, $45, $67, $8a, $cd, $ee, $f7, $7f, $ee, $dc, $a8, $76, $54, $32, $10
db $00, $11, $22, $33, $44, $33, $22, $11, $ff, $ee, $cc, $aa, $88, $aa, $cc, $ee
db $02, $46, $8a, $ce, $cb, $a9, $87, $65, $ff, $fe, $ed, $dc, $44, $33, $22, $11
db $c0, $a9, $87, $f5, $ff, $fe, $ed, $dc, $44, $33, $22, $f1, $02, $46, $8a, $ce
db $44, $33, $22, $1f, $00, $46, $8a, $ce, $f8, $fe, $ed, $dc, $cb, $a9, $87, $65
db $11, $00, $00, $08, $00, $13, $57, $9a, $b4, $ba, $a9, $98, $87, $65, $43, $21
; e8e52
NoiseSampleSetsPointers: ; e8e52
dw NoiseSampleSets0
dw NoiseSampleSets1
dw NoiseSampleSets2
dw NoiseSampleSets3
dw NoiseSampleSets4
dw NoiseSampleSets5
; e8e5e
NoiseSampleSets:
NoiseSampleSets0: ; e8e5e
dw NoiseSampleSet00 ; rest
dw NoiseSampleSet01 ; c
dw NoiseSampleSet02 ; c#
dw NoiseSampleSet03 ; d
dw NoiseSampleSet04 ; d#
dw NoiseSampleSet05 ; e
dw NoiseSampleSet06 ; f
dw NoiseSampleSet07 ; f#
dw NoiseSampleSet08 ; g
dw NoiseSampleSet09 ; g#
dw NoiseSampleSet10 ; a
dw NoiseSampleSet11 ; a#
dw NoiseSampleSet12 ; b
NoiseSampleSets1: ; e8e78
dw NoiseSampleSet00
dw NoiseSampleSet08
dw NoiseSampleSet09
dw NoiseSampleSet10
dw NoiseSampleSet11
dw NoiseSampleSet12
dw NoiseSampleSet13
dw NoiseSampleSet14
dw NoiseSampleSet15
dw NoiseSampleSet16
dw NoiseSampleSet17
dw NoiseSampleSet18
dw NoiseSampleSet19
NoiseSampleSets2: ; e8e92
dw NoiseSampleSet00
dw NoiseSampleSet01
dw NoiseSampleSet17
dw NoiseSampleSet18
dw NoiseSampleSet19
dw NoiseSampleSet05
dw NoiseSampleSet06
dw NoiseSampleSet07
dw NoiseSampleSet08
dw NoiseSampleSet09
dw NoiseSampleSet10
dw NoiseSampleSet11
dw NoiseSampleSet12
NoiseSampleSets3: ; e8eac
dw NoiseSampleSet21
dw NoiseSampleSet22
dw NoiseSampleSet23
dw NoiseSampleSet24
dw NoiseSampleSet25
dw NoiseSampleSet26
dw NoiseSampleSet20
dw NoiseSampleSet27
dw NoiseSampleSet28
dw NoiseSampleSet29
dw NoiseSampleSet21
dw NoiseSampleSet37
dw NoiseSampleSet34
NoiseSampleSets4: ; e8ec6
dw NoiseSampleSet21
dw NoiseSampleSet20
dw NoiseSampleSet23
dw NoiseSampleSet24
dw NoiseSampleSet25
dw NoiseSampleSet33
dw NoiseSampleSet26
dw NoiseSampleSet35
dw NoiseSampleSet31
dw NoiseSampleSet32
dw NoiseSampleSet36
dw NoiseSampleSet37
dw NoiseSampleSet30
NoiseSampleSets5: ; e8ee0
dw NoiseSampleSet00
dw NoiseSampleSet17
dw NoiseSampleSet18
dw NoiseSampleSet19
dw NoiseSampleSet27
dw NoiseSampleSet28
dw NoiseSampleSet29
dw NoiseSampleSet05
dw NoiseSampleSet06
dw NoiseSampleSet30
dw NoiseSampleSet24
dw NoiseSampleSet23
dw NoiseSampleSet37
; e8efa
NoiseSampleSet00: ; e8efa
; unused
db $20, $11, $00
db $ff ; end
; e8efe
NoiseSampleSet01: ; e8efe
db $20, $c1, $33
db $ff ; end
; e8f02
NoiseSampleSet02: ; e8f02
db $20, $b1, $33
db $ff ; end
; e8f06
NoiseSampleSet03: ; e8f06
db $20, $a1, $33
db $ff ; end
; e8f0a
NoiseSampleSet04: ; e8f0a
db $20, $81, $33
db $ff ; end
; e8f0e
NoiseSampleSet05: ; e8f0e
db $27, $84, $37
db $26, $84, $36
db $25, $83, $35
db $24, $83, $34
db $23, $82, $33
db $22, $81, $32
db $ff ; end
; e8f21
NoiseSampleSet06: ; e8f21
db $20, $51, $2a
db $ff ; end
; e8f25
NoiseSampleSet07: ; e8f25
db $21, $41, $2b
db $20, $61, $2a
db $ff ; end
; e8f2c
NoiseSampleSet08: ; e8f2c
db $20, $81, $10
db $ff ; end
; e8f30
NoiseSampleSet09: ; e8f30
db $20, $82, $23
db $ff ; end
; e8f34
NoiseSampleSet10: ; e8f34
db $20, $82, $25
db $ff ; end
; e8f38
NoiseSampleSet11: ; e8f38
db $20, $82, $26
db $ff ; end
; e8f3c
NoiseSampleSet12: ; e8f3c
db $20, $a1, $10
db $ff ; end
; e8f40
NoiseSampleSet13: ; e8f40
db $20, $a2, $11
db $ff ; end
; e8f44
NoiseSampleSet14: ; e8f44
db $20, $a2, $50
db $ff ; end
; e8f48
NoiseSampleSet15: ; e8f48
db $20, $a1, $18
db $20, $31, $33
db $ff ; end
; e8f4f
NoiseSampleSet16: ; e8f4f
db $22, $91, $28
db $20, $71, $18
db $ff ; end
; e8f56
NoiseSampleSet17: ; e8f56
db $20, $91, $22
db $ff ; end
; e8f5a
NoiseSampleSet18: ; e8f5a
db $20, $71, $22
db $ff ; end
; e8f5e
NoiseSampleSet19: ; e8f5e
db $20, $61, $22
db $ff ; end
; e8f62
NoiseSampleSet20: ; e8f62
db $20, $11, $11
db $ff ; end
; e8f66
NoiseSampleSet21: ; e8f66
db $ff
; e8f67
NoiseSampleSet22: ; e8f67
db $20, $91, $33
db $ff ; end
; e8f6b
NoiseSampleSet23: ; e8f6b
db $20, $51, $32
db $ff ; end
; e8f6f
NoiseSampleSet24: ; e8f6f
db $20, $81, $31
db $ff ; end
; e8f73
NoiseSampleSet25: ; e8f73
db $20, $88, $6b
db $20, $71, $00
db $ff ; end
; e8f7a
NoiseSampleSet26: ; e8f7a
db $30, $91, $18
db $ff ; end
; e8f7e
NoiseSampleSet27: ; e8f7e
db $27, $92, $10
db $ff ; end
; e8f82
NoiseSampleSet28: ; e8f82
db $33, $91, $00
db $33, $11, $00
db $ff ; end
; e8f89
NoiseSampleSet29: ; e8f89
db $33, $91, $11
db $33, $11, $00
db $ff ; end
; e8f90
NoiseSampleSet30: ; e8f90
db $33, $88, $15
db $20, $65, $12
db $ff ; end
; e8f97
NoiseSampleSet31: ; e8f97
db $33, $51, $21
db $33, $11, $11
db $ff ; end
; e8f9e
NoiseSampleSet32: ; e8f9e
db $33, $51, $50
db $33, $11, $11
db $ff ; end
; e8fa5
NoiseSampleSet33: ; e8fa5
db $20, $a1, $31
db $ff ; end
; e8fa9
NoiseSampleSet34: ; e8fa9
db $20, $84, $12
db $ff ; end
; e8fad
NoiseSampleSet35: ; e8fad
db $33, $81, $00
db $33, $11, $00
db $ff ; end
; e8fb4
NoiseSampleSet36: ; e8fb4
db $33, $81, $21
db $33, $11, $11
db $ff ; end
; e8fbb
NoiseSampleSet37: ; e8fbb
db $20, $a8, $6b
db $20, $71, $00
db $ff ; end
; e8fc2
GetLRTracks: ; e8fc2
; gets the default sound l/r channels
; stores mono/stereo table in hl
ld a, [Options]
bit 5, a ; stereo
; made redundant, could have had a purpose in gold
jr nz, .stereo
ld hl, MonoTracks
ret
.stereo
ld hl, StereoTracks
ret
; e8fd1
MonoTracks: ; e8fd1
; bit corresponds to track #
; hi: left channel
; lo: right channel
db $11, $22, $44, $88
; e8fd5
StereoTracks: ; e8fd5
; made redundant
; seems to be modified on a per-song basis
db $11, $22, $44, $88
; e8fd9
ChannelPointers: ; e8fd9
; music channels
dw Channel1
dw Channel2
dw Channel3
dw Channel4
; sfx channels
dw Channel5
dw Channel6
dw Channel7
dw Channel8
; e8fe9
ClearChannels:: ; e8fe9
; runs ClearChannel for all 4 channels
; doesn't seem to be used, but functionally identical to SoundRestart
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ld hl, rNR50
xor a
ld [hli], a
ld [hli], a
ld a, $80
ld [hli], a
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ld hl, rNR10
ld e, $04
.loop
call ClearChannel
dec e
jr nz, .loop
ret
; e8ffe
ClearChannel: ; e8ffe
2013-02-19 23:46:40 -08:00
; input: hl = beginning hw sound register (rNR10, $ff15, rNR30, $ff1f)
; output: 00 00 80 00 80
; sound channel 1 2 3 4
xor a
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ld [hli], a ; rNR10, $ff15, rNR30, $ff1f ; sweep = 0
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ld [hli], a ; rNR11, rNR21, rNR31, rNR41 ; length/wavepattern = 0
ld a, $08
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ld [hli], a ; rNR12, rNR22, rNR32, rNR42 ; envelope = 0
xor a
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ld [hli], a ; rNR13, rNR23, rNR33, rNR43 ; frequency lo = 0
ld a, $80
2013-02-19 23:46:40 -08:00
ld [hli], a ; rNR14, rNR24, rNR34, rNR44 ; restart sound (freq hi = 0)
ret
; e900a