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-rw-r--r--audio/duty_1.asm33
-rw-r--r--audio/duty_2.asm32
-rw-r--r--audio/duty_3.asm33
-rw-r--r--audio/engine_1.asm1682
-rw-r--r--audio/engine_2.asm1733
-rw-r--r--audio/engine_3.asm1682
6 files changed, 5195 insertions, 0 deletions
diff --git a/audio/duty_1.asm b/audio/duty_1.asm
new file mode 100644
index 00000000..2c650ac1
--- /dev/null
+++ b/audio/duty_1.asm
@@ -0,0 +1,33 @@
+Music2_Channel3DutyPointers: ; 0x8361
+ dw Music2_Channel3Duty0
+ dw Music2_Channel3Duty1
+ dw Music2_Channel3Duty2
+ dw Music2_Channel3Duty3
+ dw Music2_Channel3Duty4
+ dw Music2_Channel3Duty5 ; used in the Lavender Town theme
+ dw Music2_Channel3Duty5 ; unused
+ dw Music2_Channel3Duty5 ; unused
+ dw Music2_Channel3Duty5 ; unused
+
+; these are the definitions for the channel 3 instruments
+; each instrument definition is made up of 32 points (nibbles) that form
+; the graph of the wave
+; the current instrument is copied to $FF30
+Music2_Channel3Duty0: ; 0x8373
+ db $02,$46,$8A,$CE,$FF,$FE,$ED,$DC,$CB,$A9,$87,$65,$44,$33,$22,$11
+
+Music2_Channel3Duty1: ; 0x8383
+ db $02,$46,$8A,$CE,$EF,$FF,$FE,$EE,$DD,$CB,$A9,$87,$65,$43,$22,$11
+
+Music2_Channel3Duty2: ; 0x8393
+ db $13,$69,$BD,$EE,$EE,$FF,$FF,$ED,$DE,$FF,$FF,$EE,$EE,$DB,$96,$31
+
+Music2_Channel3Duty3: ; 0x83a3
+ db $02,$46,$8A,$CD,$EF,$FE,$DE,$FF,$EE,$DC,$BA,$98,$76,$54,$32,$10
+
+Music2_Channel3Duty4: ; 0x83b3
+ db $01,$23,$45,$67,$8A,$CD,$EE,$F7,$7F,$EE,$DC,$A8,$76,$54,$32,$10
+
+; duty 5 reads from sfx data
+Music2_Channel3Duty5: ; 0x83c3
+
diff --git a/audio/duty_2.asm b/audio/duty_2.asm
new file mode 100644
index 00000000..b4561091
--- /dev/null
+++ b/audio/duty_2.asm
@@ -0,0 +1,32 @@
+Music8_Channel3DutyPointers: ; 20361 (8:4361)
+ dw Music8_Channel3Duty0
+ dw Music8_Channel3Duty1
+ dw Music8_Channel3Duty2
+ dw Music8_Channel3Duty3
+ dw Music8_Channel3Duty4
+ dw Music8_Channel3Duty5 ; unused
+ dw Music8_Channel3Duty5 ; unused
+ dw Music8_Channel3Duty5 ; unused
+ dw Music8_Channel3Duty5 ; unused
+
+; these are the definitions for the channel 3 instruments
+; each instrument definition is made up of 32 points (nibbles) that form
+; the graph of the wave
+; the current instrument is copied to $FF30
+Music8_Channel3Duty0: ; 20373 (8:4373)
+ db $02,$46,$8A,$CE,$FF,$FE,$ED,$DC,$CB,$A9,$87,$65,$44,$33,$22,$11
+
+Music8_Channel3Duty1: ; 20383 (8:4383)
+ db $02,$46,$8A,$CE,$EF,$FF,$FE,$EE,$DD,$CB,$A9,$87,$65,$43,$22,$11
+
+Music8_Channel3Duty2: ; 20393 (8:4393)
+ db $13,$69,$BD,$EE,$EE,$FF,$FF,$ED,$DE,$FF,$FF,$EE,$EE,$DB,$96,$31
+
+Music8_Channel3Duty3: ; 203a3 (8:43a3)
+ db $02,$46,$8A,$CD,$EF,$FE,$DE,$FF,$EE,$DC,$BA,$98,$76,$54,$32,$10
+
+Music8_Channel3Duty4: ; 203b3 (8:43b3)
+ db $01,$23,$45,$67,$8A,$CD,$EE,$F7,$7F,$EE,$DC,$A8,$76,$54,$32,$10
+
+Music8_Channel3Duty5:
+
diff --git a/audio/duty_3.asm b/audio/duty_3.asm
new file mode 100644
index 00000000..b9702a7f
--- /dev/null
+++ b/audio/duty_3.asm
@@ -0,0 +1,33 @@
+Music1f_Channel3DutyPointers: ; 7c361 (1f:4361)
+ dw Music1f_Channel3Duty0
+ dw Music1f_Channel3Duty1
+ dw Music1f_Channel3Duty2
+ dw Music1f_Channel3Duty3
+ dw Music1f_Channel3Duty4
+ dw Music1f_Channel3Duty5 ; used in the Pokemon Tower theme
+ dw Music1f_Channel3Duty5 ; unused
+ dw Music1f_Channel3Duty5 ; unused
+ dw Music1f_Channel3Duty5 ; unused
+
+; these are the definitions for the channel 3 instruments
+; each instrument definition is made up of 32 points (nibbles) that form
+; the graph of the wave
+; the current instrument is copied to $FF30
+Music1f_Channel3Duty0: ; 7c373 (1f:4373)
+ db $02,$46,$8A,$CE,$FF,$FE,$ED,$DC,$CB,$A9,$87,$65,$44,$33,$22,$11
+
+Music1f_Channel3Duty1: ; 7c383 (1f:4383)
+ db $02,$46,$8A,$CE,$EF,$FF,$FE,$EE,$DD,$CB,$A9,$87,$65,$43,$22,$11
+
+Music1f_Channel3Duty2: ; 7c393 (1f:4393)
+ db $13,$69,$BD,$EE,$EE,$FF,$FF,$ED,$DE,$FF,$FF,$EE,$EE,$DB,$96,$31
+
+Music1f_Channel3Duty3: ; 7c3a3 (1f:43a3)
+ db $02,$46,$8A,$CD,$EF,$FE,$DE,$FF,$EE,$DC,$BA,$98,$76,$54,$32,$10
+
+Music1f_Channel3Duty4: ; 7c3b3 (1f:43b3)
+ db $01,$23,$45,$67,$8A,$CD,$EE,$F7,$7F,$EE,$DC,$A8,$76,$54,$32,$10
+
+; duty 5 reads from sfx data
+Music1f_Channel3Duty5: ; 7c3c3 (1f:43c3)
+
diff --git a/audio/engine_1.asm b/audio/engine_1.asm
new file mode 100644
index 00000000..0d60308a
--- /dev/null
+++ b/audio/engine_1.asm
@@ -0,0 +1,1682 @@
+; The first of three duplicated sound engines.
+
+Func_9103: ; 0x9103
+ ld c, CH0
+.loop
+ ld b, $0
+ ld hl, $c026
+ add hl, bc
+ ld a, [hl]
+ and a
+ jr z, .nextChannel
+ ld a, c
+ cp CH4
+ jr nc, .asm_912e ; if sfx channel
+ ld a, [$c002]
+ and a
+ jr z, .asm_912e
+ bit 7, a
+ jr nz, .nextChannel
+ set 7, a
+ ld [$c002], a
+ xor a
+ ld [$ff00+$25], a
+ ld [$ff00+$1a], a
+ ld a, $80
+ ld [$ff00+$1a], a
+ jr .nextChannel
+.asm_912e
+ call Music2_ApplyMusicAffects
+.nextChannel
+ ld a, c
+ inc c ; inc channel number
+ cp CH7
+ jr nz, .loop
+ ret
+
+; this routine checks flags for music effects currently applied
+; to the channel and calls certain functions based on flags.
+; known flags for $c02e:
+; 1: call has been used
+; 3: a toggle used only by this routine for vibrato
+; 4: pitchbend flag
+; 6: dutycycle flag
+Music2_ApplyMusicAffects: ; 0x9138
+ ld b, $0
+ ld hl, $c0b6 ; delay unitl next note
+ add hl, bc
+ ld a, [hl]
+ cp $1 ; if the delay is 1, play next note
+ jp z, Music2_PlayNextNote
+ dec a ; otherwise, decrease the delay timer
+ ld [hl], a
+ ld a, c
+ cp CH4
+ jr nc, .startChecks ; if a sfx channel
+ ld hl, $c02a
+ add hl, bc
+ ld a, [hl]
+ and a
+ jr z, .startChecks
+ ret
+.startChecks
+ ld hl, $c02e
+ add hl, bc
+ bit 6, [hl] ; dutycycle
+ jr z, .checkForExecuteMusic
+ call Music2_ApplyDutyCycle
+.checkForExecuteMusic
+ ld b, $0
+ ld hl, $c036
+ add hl, bc
+ bit 0, [hl]
+ jr nz, .checkForPitchBend
+ ld hl, $c02e
+ add hl, bc
+ bit 2, [hl]
+ jr nz, .disablePitchBendVibrato
+.checkForPitchBend
+ ld hl, $c02e
+ add hl, bc
+ bit 4, [hl] ; pitchbend
+ jr z, .checkVibratoDelay
+ jp Music2_ApplyPitchBend
+.checkVibratoDelay
+ ld hl, $c04e ; vibrato delay
+ add hl, bc
+ ld a, [hl]
+ and a ; check if delay is over
+ jr z, .checkForVibrato
+ dec [hl] ; otherwise, dec delay
+.disablePitchBendVibrato
+ ret
+.checkForVibrato
+ ld hl, $c056 ; vibrato rate
+ add hl, bc
+ ld a, [hl]
+ and a
+ jr nz, .vibrato
+ ret ; no vibrato
+.vibrato
+ ld d, a
+ ld hl, $c05e
+ add hl, bc
+ ld a, [hl]
+ and $f
+ and a
+ jr z, .vibratoAlreadyDone
+ dec [hl] ; apply vibrato pitch change
+ ret
+.vibratoAlreadyDone
+ ld a, [hl]
+ swap [hl]
+ or [hl]
+ ld [hl], a ; reset the vibrato value and start again
+ ld hl, $c066
+ add hl, bc
+ ld e, [hl] ; get note pitch
+ ld hl, $c02e
+ add hl, bc
+ bit 3, [hl] ; this is the only code that sets/resets bit three so
+ jr z, .unset ; it continuously alternates which path it takes
+ res 3, [hl]
+ ld a, d
+ and $f
+ ld d, a
+ ld a, e
+ sub d
+ jr nc, .noCarry
+ ld a, $0
+.noCarry
+ jr .done
+.unset
+ set 3, [hl]
+ ld a, d
+ and $f0
+ swap a
+ add e
+ jr nc, .done
+ ld a, $ff
+.done
+ ld d, a
+ ld b, $3
+ call Func_9838
+ ld [hl], d
+ ret
+
+; this routine executes all music commands that take up no time,
+; like tempo changes, duty changes etc. and doesn't return
+; until the first note is reached
+Music2_PlayNextNote ; 0x91d0
+ ld hl, $c06e
+ add hl, bc
+ ld a, [hl]
+ ld hl, $c04e
+ add hl, bc
+ ld [hl], a
+ ld hl, $c02e
+ add hl, bc
+ res 4, [hl]
+ res 5, [hl]
+ call Music2_endchannel
+ ret
+
+Music2_endchannel: ; 0x91e6
+ call Music2_GetNextMusicByte
+ ld d, a
+ cp $ff ; is this command an endchannel?
+ jp nz, Music2_callchannel ; no
+ ld b, $0 ; yes
+ ld hl, $c02e
+ add hl, bc
+ bit 1, [hl]
+ jr nz, .returnFromCall
+ ld a, c
+ cp CH3
+ jr nc, .noiseOrSfxChannel
+ jr .asm_923f
+.noiseOrSfxChannel
+ res 2, [hl]
+ ld hl, $c036
+ add hl, bc
+ res 0, [hl]
+ cp CH6
+ jr nz, .notSfxChannel3
+ ld a, $0
+ ld [$ff00+$1a], a
+ ld a, $80
+ ld [$ff00+$1a], a
+.notSfxChannel3
+ jr nz, .asm_9222
+ ld a, [$c003]
+ and a
+ jr z, .asm_9222
+ xor a
+ ld [$c003], a
+ jr .asm_923f
+.asm_9222
+ jr .asm_9248
+.returnFromCall
+ res 1, [hl]
+ ld d, $0
+ ld a, c
+ add a
+ ld e, a
+ ld hl, $c006
+ add hl, de
+ push hl ; store current channel address
+ ld hl, $c016
+ add hl, de
+ ld e, l
+ ld d, h
+ pop hl
+ ld a, [de]
+ ld [hli], a
+ inc de
+ ld a, [de]
+ ld [hl], a ; loads channel address to return to
+ jp Music2_endchannel
+.asm_923f
+ ld hl, Unknown_9b1f
+ add hl, bc
+ ld a, [$ff00+$25]
+ and [hl]
+ ld [$ff00+$25], a
+.asm_9248
+ ld a, [$c02a]
+ cp $14
+ jr nc, .asm_9251
+ jr .asm_926e
+.asm_9251
+ ld a, [$c02a]
+ cp $86
+ jr z, .asm_926e
+ jr c, .asm_925c
+ jr .asm_926e
+.asm_925c
+ ld a, c
+ cp CH4
+ jr z, .asm_9265
+ call Func_96c7
+ ret c
+.asm_9265
+ ld a, [$c005]
+ ld [$ff00+$24], a
+ xor a
+ ld [$c005], a
+.asm_926e
+ ld hl, $c026
+ add hl, bc
+ ld [hl], b
+ ret
+
+Music2_callchannel: ; 0x9274
+ cp $fd ; is this command a callchannel?
+ jp nz, Music2_loopchannel ; no
+ call Music2_GetNextMusicByte ; yes
+ push af
+ call Music2_GetNextMusicByte
+ ld d, a
+ pop af
+ ld e, a
+ push de ; store pointer
+ ld d, $0
+ ld a, c
+ add a
+ ld e, a
+ ld hl, $c006
+ add hl, de
+ push hl
+ ld hl, $c016
+ add hl, de
+ ld e, l
+ ld d, h
+ pop hl
+ ld a, [hli]
+ ld [de], a
+ inc de
+ ld a, [hld]
+ ld [de], a ; copy current channel address
+ pop de
+ ld [hl], e
+ inc hl
+ ld [hl], d ; overwrite current address with pointer
+ ld b, $0
+ ld hl, $c02e
+ add hl, bc
+ set 1, [hl] ; set the call flag
+ jp Music2_endchannel
+
+Music2_loopchannel: ; 0x92a9
+ cp $fe ; is this command a loopchannel?
+ jp nz, Music2_notetype ; no
+ call Music2_GetNextMusicByte ; yes
+ ld e, a
+ and a
+ jr z, .infiniteLoop
+ ld b, $0
+ ld hl, $c0be
+ add hl, bc
+ ld a, [hl]
+ cp e
+ jr nz, .loopAgain
+ ld a, $1 ; if no more loops to make,
+ ld [hl], a
+ call Music2_GetNextMusicByte ; skip pointer
+ call Music2_GetNextMusicByte
+ jp Music2_endchannel
+.loopAgain ; inc loop count
+ inc a
+ ld [hl], a
+ ; fall through
+.infiniteLoop ; overwrite current address with pointer
+ call Music2_GetNextMusicByte
+ push af
+ call Music2_GetNextMusicByte
+ ld b, a
+ ld d, $0
+ ld a, c
+ add a
+ ld e, a
+ ld hl, $c006
+ add hl, de
+ pop af
+ ld [hli], a
+ ld [hl], b
+ jp Music2_endchannel
+
+Music2_notetype: ; 0x92e4
+ and $f0
+ cp $d0 ; is this command a notetype?
+ jp nz, Music2_togglecall ; no
+ ld a, d ; yes
+ and $f
+ ld b, $0
+ ld hl, $c0c6
+ add hl, bc
+ ld [hl], a ; store low nibble as speed
+ ld a, c
+ cp CH3
+ jr z, .noiseChannel ; noise channel has 0 params
+ call Music2_GetNextMusicByte
+ ld d, a
+ ld a, c
+ cp CH2
+ jr z, .musicChannel3
+ cp CH6
+ jr nz, .notChannel3
+ ld hl, $c0e7
+ jr .sfxChannel3
+.musicChannel3
+ ld hl, $c0e6
+.sfxChannel3
+ ld a, d
+ and $f
+ ld [hl], a ; store low nibble of param as duty
+ ld a, d
+ and $30
+ sla a
+ ld d, a
+ ; fall through
+
+ ; if channel 3, store high nibble as volume
+ ; else, store volume (high nibble) and fade (low nibble)
+.notChannel3
+ ld b, $0
+ ld hl, $c0de
+ add hl, bc
+ ld [hl], d
+.noiseChannel
+ jp Music2_endchannel
+
+Music2_togglecall: ; 0x9323
+ ld a, d
+ cp $e8 ; is this command an togglecall?
+ jr nz, Music2_vibrato ; no
+ ld b, $0 ; yes
+ ld hl, $c02e
+ add hl, bc
+ ld a, [hl]
+ xor $1
+ ld [hl], a ; flip bit 0 of $c02e (toggle returning from call)
+ jp Music2_endchannel
+
+Music2_vibrato: ; 0x9335
+ cp $ea ; is this command a vibrato?
+ jr nz, Music2_pitchbend ; no
+ call Music2_GetNextMusicByte ; yes
+ ld b, $0
+ ld hl, $c04e
+ add hl, bc
+ ld [hl], a ; store delay
+ ld hl, $c06e
+ add hl, bc
+ ld [hl], a ; store delay
+ call Music2_GetNextMusicByte
+ ld d, a
+ and $f0
+ swap a
+ ld b, $0
+ ld hl, $c056
+ add hl, bc
+ srl a
+ ld e, a
+ adc b
+ swap a
+ or e
+ ld [hl], a ; store rate as both high and low nibbles
+ ld a, d
+ and $f
+ ld d, a
+ ld hl, $c05e
+ add hl, bc
+ swap a
+ or d
+ ld [hl], a ; store depth as both high and low nibbles
+ jp Music2_endchannel
+
+Music2_pitchbend: ; 0x936d
+ cp $eb ; is this command a pitchbend?
+ jr nz, Music2_duty ; no
+ call Music2_GetNextMusicByte ; yes
+ ld b, $0
+ ld hl, $c076
+ add hl, bc
+ ld [hl], a ; store first param
+ call Music2_GetNextMusicByte
+ ld d, a
+ and $f0
+ swap a
+ ld b, a
+ ld a, d
+ and $f
+ call Func_9858
+ ld b, $0
+ ld hl, $c0a6
+ add hl, bc
+ ld [hl], d ; store unknown part of second param
+ ld hl, $c0ae
+ add hl, bc
+ ld [hl], e ; store unknown part of second param
+ ld b, $0
+ ld hl, $c02e
+ add hl, bc
+ set 4, [hl] ; set pitchbend flag
+ call Music2_GetNextMusicByte
+ ld d, a
+ jp Music2_notelength
+
+Music2_duty: ; 0x93a5
+ cp $ec ; is this command a duty?
+ jr nz, Music2_tempo ; no
+ call Music2_GetNextMusicByte ; yes
+ rrca
+ rrca
+ and $c0
+ ld b, $0
+ ld hl, $c03e
+ add hl, bc
+ ld [hl], a ; store duty
+ jp Music2_endchannel
+
+Music2_tempo: ; 0x93ba
+ cp $ed ; is this command a tempo?
+ jr nz, Music2_unknownmusic0xee ; no
+ ld a, c ; yes
+ cp CH4
+ jr nc, .sfxChannel
+ call Music2_GetNextMusicByte
+ ld [$c0e8], a ; store first param
+ call Music2_GetNextMusicByte
+ ld [$c0e9], a ; store second param
+ xor a
+ ld [$c0ce], a ; clear RAM
+ ld [$c0cf], a
+ ld [$c0d0], a
+ ld [$c0d1], a
+ jr .musicChannelDone
+.sfxChannel
+ call Music2_GetNextMusicByte
+ ld [$c0ea], a ; store first param
+ call Music2_GetNextMusicByte
+ ld [$c0eb], a ; store second param
+ xor a
+ ld [$c0d2], a ; clear RAM
+ ld [$c0d3], a
+ ld [$c0d4], a
+ ld [$c0d5], a
+.musicChannelDone
+ jp Music2_endchannel
+
+Music2_unknownmusic0xee: ; 0x93fa
+ cp $ee ; is this command an unknownmusic0xee?
+ jr nz, Music2_unknownmusic0xef ; no
+ call Music2_GetNextMusicByte ; yes
+ ld [$c004], a ; store first param
+ jp Music2_endchannel
+
+; this appears to never be used
+Music2_unknownmusic0xef ; 0x9407
+ cp $ef ; is this command an unknownmusic0xef?
+ jr nz, Music2_dutycycle ; no
+ call Music2_GetNextMusicByte ; yes
+ push bc
+ call Func_9876
+ pop bc
+ ld a, [$c003]
+ and a
+ jr nz, .skip
+ ld a, [$c02d]
+ ld [$c003], a
+ xor a
+ ld [$c02d], a
+.skip
+ jp Music2_endchannel
+
+Music2_dutycycle: ; 0x9426
+ cp $fc ; is this command a dutycycle?
+ jr nz, Music2_stereopanning ; no
+ call Music2_GetNextMusicByte ; yes
+ ld b, $0
+ ld hl, $c046
+ add hl, bc
+ ld [hl], a ; store full cycle
+ and $c0
+ ld hl, $c03e
+ add hl, bc
+ ld [hl], a ; store first duty
+ ld hl, $c02e
+ add hl, bc
+ set 6, [hl] ; set dutycycle flag
+ jp Music2_endchannel
+
+Music2_stereopanning: ; 0x9444
+ cp $f0 ; is this command a stereopanning?
+ jr nz, Music2_executemusic ; no
+ call Music2_GetNextMusicByte ; yes
+ ld [$ff00+$24], a ; store stereopanning
+ jp Music2_endchannel
+
+Music2_executemusic: ; 0x9450
+ cp $f8 ; is this command an executemusic?
+ jr nz, Music2_octave ; no
+ ld b, $0 ; yes
+ ld hl, $c036
+ add hl, bc
+ set 0, [hl]
+ jp Music2_endchannel
+
+Music2_octave: ; 0x945f
+ and $f0
+ cp $e0 ; is this command an octave?
+ jr nz, Music2_unknownsfx0x20 ; no
+ ld hl, $c0d6 ; yes
+ ld b, $0
+ add hl, bc
+ ld a, d
+ and $f
+ ld [hl], a ; store low nibble as octave
+ jp Music2_endchannel
+
+Music2_unknownsfx0x20: ; 0x9472
+ cp $20 ; is this command an unknownsfx0x20?
+ jr nz, Music2_unknownsfx0x10 ; no
+ ld a, c
+ cp CH3 ; is this a noise or sfx channel?
+ jr c, Music2_unknownsfx0x10 ; no
+ ld b, $0
+ ld hl, $c036
+ add hl, bc
+ bit 0, [hl]
+ jr nz, Music2_unknownsfx0x10 ; no
+ call Music2_notelength ; yes
+ ld d, a
+ ld b, $0
+ ld hl, $c03e
+ add hl, bc
+ ld a, [hl]
+ or d
+ ld d, a
+ ld b, $1
+ call Func_9838
+ ld [hl], d
+ call Music2_GetNextMusicByte
+ ld d, a
+ ld b, $2
+ call Func_9838
+ ld [hl], d
+ call Music2_GetNextMusicByte
+ ld e, a
+ ld a, c
+ cp CH7
+ ld a, $0
+ jr z, .sfxNoiseChannel ; only two params for noise channel
+ push de
+ call Music2_GetNextMusicByte
+ pop de
+.sfxNoiseChannel
+ ld d, a
+ push de
+ call Func_9629
+ call Func_95f8
+ pop de
+ call Func_964b
+ ret
+
+Music2_unknownsfx0x10:
+ ld a, c
+ cp CH4
+ jr c, Music2_note ; if not a sfx
+ ld a, d
+ cp $10 ; is this command a unknownsfx0x10?
+ jr nz, Music2_note ; no
+ ld b, $0
+ ld hl, $c036
+ add hl, bc
+ bit 0, [hl]
+ jr nz, Music2_note ; no
+ call Music2_GetNextMusicByte ; yes
+ ld [$ff00+$10], a
+ jp Music2_endchannel
+
+Music2_note:
+ ld a, c
+ cp CH3
+ jr nz, Music2_notelength ; if not noise channel
+ ld a, d
+ and $f0
+ cp $b0 ; is this command a dnote?
+ jr z, Music2_dnote ; yes
+ jr nc, Music2_notelength ; no
+ swap a
+ ld b, a
+ ld a, d
+ and $f
+ ld d, a
+ ld a, b
+ push de
+ push bc
+ jr asm_94fd
+
+Music2_dnote:
+ ld a, d
+ and $f
+ push af
+ push bc
+ call Music2_GetNextMusicByte ; get dnote instrument
+asm_94fd
+ ld d, a
+ ld a, [$c003]
+ and a
+ jr nz, .asm_9508
+ ld a, d
+ call Func_9876
+.asm_9508
+ pop bc
+ pop de
+
+Music2_notelength: ; 0x950a
+ ld a, d
+ push af
+ and $f
+ inc a
+ ld b, $0
+ ld e, a ; store note length (in 16ths)
+ ld d, b
+ ld hl, $c0c6
+ add hl, bc
+ ld a, [hl]
+ ld l, b
+ call Func_9847
+ ld a, c
+ cp CH4
+ jr nc, .sfxChannel
+ ld a, [$c0e8]
+ ld d, a
+ ld a, [$c0e9]
+ ld e, a
+ jr .skip
+.sfxChannel
+ ld d, $1
+ ld e, $0
+ cp CH7
+ jr z, .skip ; if noise channel
+ call Func_9693
+ ld a, [$c0ea]
+ ld d, a
+ ld a, [$c0eb]
+ ld e, a
+.skip
+ ld a, l
+ ld b, $0
+ ld hl, $c0ce
+ add hl, bc
+ ld l, [hl]
+ call Func_9847
+ ld e, l
+ ld d, h
+ ld hl, $c0ce
+ add hl, bc
+ ld [hl], e
+ ld a, d
+ ld hl, $c0b6
+ add hl, bc
+ ld [hl], a
+ ld hl, $c036
+ add hl, bc
+ bit 0, [hl]
+ jr nz, Music2_notepitch
+ ld hl, $c02e
+ add hl, bc
+ bit 2, [hl]
+ jr z, Music2_notepitch
+ pop hl
+ ret
+
+Music2_notepitch: ; 0x9568
+ pop af
+ and $f0
+ cp $c0 ; compare to rest
+ jr nz, .notRest
+ ld a, c
+ cp CH4
+ jr nc, .sfxChannel
+ ld hl, $c02a
+ add hl, bc
+ ld a, [hl]
+ and a
+ jr nz, .done
+ ; fall through
+.sfxChannel
+ ld a, c
+ cp CH2
+ jr z, .musicChannel3
+ cp CH6
+ jr nz, .notSfxChannel3
+.musicChannel3
+ ld b, $0
+ ld hl, Unknown_9b1f
+ add hl, bc
+ ld a, [$ff00+$25]
+ and [hl]
+ ld [$ff00+$25], a
+ jr .done
+.notSfxChannel3
+ ld b, $2
+ call Func_9838
+ ld a, $8
+ ld [hli], a
+ inc hl
+ ld a, $80
+ ld [hl], a
+.done
+ ret
+.notRest
+ swap a
+ ld b, $0
+ ld hl, $c0d6
+ add hl, bc
+ ld b, [hl]
+ call Func_9858
+ ld b, $0
+ ld hl, $c02e
+ add hl, bc
+ bit 4, [hl]
+ jr z, .asm_95b8
+ call Func_978f
+.asm_95b8
+ push de
+ ld a, c
+ cp CH4
+ jr nc, .skip ; if sfx channel
+ ld hl, $c02a
+ ld d, $0
+ ld e, a
+ add hl, de
+ ld a, [hl]
+ and a
+ jr nz, .asm_95cb
+ jr .skip
+.asm_95cb
+ pop de
+ ret
+.skip
+ ld b, $0
+ ld hl, $c0de
+ add hl, bc
+ ld d, [hl]
+ ld b, $2
+ call Func_9838
+ ld [hl], d
+ call Func_9629
+ call Func_95f8
+ pop de
+ ld b, $0
+ ld hl, $c02e
+ add hl, bc
+ bit 0, [hl]
+ jr z, .asm_95ef
+ inc e
+ jr nc, .asm_95ef
+ inc d
+.asm_95ef
+ ld hl, $c066
+ add hl, bc
+ ld [hl], e
+ call Func_964b
+ ret
+
+Func_95f8: ; 0x95f8
+ ld b, $0
+ ld hl, Unknown_9b27
+ add hl, bc
+ ld a, [$ff00+$25]
+ or [hl]
+ ld d, a
+ ld a, c
+ cp CH7
+ jr z, .sfxNoiseChannel
+ cp CH4
+ jr nc, .skip ; if sfx channel
+ ld hl, $c02a
+ add hl, bc
+ ld a, [hl]
+ and a
+ jr nz, .skip
+.sfxNoiseChannel
+ ld a, [$c004]
+ ld hl, Unknown_9b27
+ add hl, bc
+ and [hl]
+ ld d, a
+ ld a, [$ff00+$25]
+ ld hl, Unknown_9b1f
+ add hl, bc
+ and [hl]
+ or d
+ ld d, a
+.skip
+ ld a, d
+ ld [$ff00+$25], a
+ ret
+
+Func_9629: ; 0x9629
+ ld b, $0
+ ld hl, $c0b6
+ add hl, bc
+ ld d, [hl]
+ ld a, c
+ cp CH2
+ jr z, .channel3 ; if music channel 3
+ cp CH6
+ jr z, .channel3 ; if sfx channel 3
+ ld a, d
+ and $3f
+ ld d, a
+ ld hl, $c03e
+ add hl, bc
+ ld a, [hl]
+ or d
+ ld d, a
+.channel3
+ ld b, $1
+ call Func_9838
+ ld [hl], d
+ ret
+
+Func_964b: ; 0x964b
+ ld a, c
+ cp CH2
+ jr z, .channel3
+ cp CH6
+ jr nz, .notSfxChannel3
+ ; fall through
+.channel3
+ push de
+ ld de, $c0e6
+ cp CH2
+ jr z, .musicChannel3
+ ld de, $c0e7
+.musicChannel3
+ ld a, [de]
+ add a
+ ld d, $0
+ ld e, a
+ ld hl, Music2_Channel3DutyPointers
+ add hl, de
+ ld e, [hl]
+ inc hl
+ ld d, [hl]
+ ld hl, $ff30
+ ld b, $f
+ ld a, $0
+ ld [$ff00+$1a], a
+.loop
+ ld a, [de]
+ inc de
+ ld [hli], a
+ ld a, b
+ dec b
+ and a
+ jr nz, .loop
+ ld a, $80
+ ld [$ff00+$1a], a
+ pop de
+.notSfxChannel3
+ ld a, d
+ or $80
+ and $c7
+ ld d, a
+ ld b, $3
+ call Func_9838
+ ld [hl], e
+ inc hl
+ ld [hl], d
+ call Func_96b5
+ ret
+
+Func_9693: ; 0x9693
+ call Func_96e5
+ jr nc, .asm_96ab
+ ld d, $0
+ ld a, [$c0f2]
+ add $80
+ jr nc, .asm_96a2
+ inc d
+.asm_96a2
+ ld [$c0eb], a
+ ld a, d
+ ld [$c0ea], a
+ jr .asm_96b4
+.asm_96ab
+ xor a
+ ld [$c0eb], a
+ ld a, $1
+ ld [$c0ea], a
+.asm_96b4
+ ret
+
+Func_96b5: ; 0x96b5
+ call Func_96e5
+ jr nc, .asm_96c6
+ ld a, [$c0f1]
+ add e
+ jr nc, .asm_96c1
+ inc d
+.asm_96c1
+ dec hl
+ ld e, a
+ ld [hl], e
+ inc hl
+ ld [hl], d
+.asm_96c6
+ ret
+
+Func_96c7: ; 0x96c7
+ call Func_96e5
+ jr nc, .asm_96e2
+ ld hl, $c006
+ ld e, c
+ ld d, $0
+ sla e
+ rl d
+ add hl, de
+ ld a, [hl]
+ sub $1
+ ld [hl], a
+ inc hl
+ ld a, [hl]
+ sbc $0
+ ld [hl], a
+ scf
+ ret
+.asm_96e2
+ scf
+ ccf
+ ret
+
+Func_96e5: ; 0x96e5
+ ld a, [$c02a]
+ cp $14
+ jr nc, .asm_96ee
+ jr .asm_96f4
+.asm_96ee
+ cp $86
+ jr z, .asm_96f4
+ jr c, .asm_96f7
+.asm_96f4
+ scf
+ ccf
+ ret
+.asm_96f7
+ scf
+ ret
+
+Music2_ApplyPitchBend: ; 0x96f9
+ ld hl, $c02e
+ add hl, bc
+ bit 5, [hl]
+ jp nz, .asm_9740
+ ld hl, $c09e
+ add hl, bc
+ ld e, [hl]
+ ld hl, $c096
+ add hl, bc
+ ld d, [hl]
+ ld hl, $c07e
+ add hl, bc
+ ld l, [hl]
+ ld h, b
+ add hl, de
+ ld d, h
+ ld e, l
+ ld hl, $c08e
+ add hl, bc
+ push hl
+ ld hl, $c086
+ add hl, bc
+ ld a, [hl]
+ pop hl
+ add [hl]
+ ld [hl], a
+ ld a, $0
+ adc e
+ ld e, a
+ ld a, $0
+ adc d
+ ld d, a
+ ld hl, $c0a6
+ add hl, bc
+ ld a, [hl]
+ cp d
+ jp c, .asm_9786
+ jr nz, .asm_9773
+ ld hl, $c0ae
+ add hl, bc
+ ld a, [hl]
+ cp e
+ jp c, .asm_9786
+ jr .asm_9773
+.asm_9740
+ ld hl, $c09e
+ add hl, bc
+ ld a, [hl]
+ ld hl, $c096
+ add hl, bc
+ ld d, [hl]
+ ld hl, $c07e
+ add hl, bc
+ ld e, [hl]
+ sub e
+ ld e, a
+ ld a, d
+ sbc b
+ ld d, a
+ ld hl, $c086
+ add hl, bc
+ ld a, [hl]
+ add a
+ ld [hl], a
+ ld a, e
+ sbc b
+ ld e, a
+ ld a, d
+ sbc b
+ ld d, a
+ ld hl, $c0a6
+ add hl, bc
+ ld a, d
+ cp [hl]
+ jr c, .asm_9786
+ jr nz, .asm_9773
+ ld hl, $c0ae
+ add hl, bc
+ ld a, e
+ cp [hl]
+ jr c, .asm_9786
+.asm_9773
+ ld hl, $c09e
+ add hl, bc
+ ld [hl], e
+ ld hl, $c096
+ add hl, bc
+ ld [hl], d
+ ld b, $3
+ call Func_9838
+ ld a, e
+ ld [hli], a
+ ld [hl], d
+ ret
+.asm_9786
+ ld hl, $c02e
+ add hl, bc
+ res 4, [hl]
+ res 5, [hl]
+ ret
+
+Func_978f: ; 0x978f
+ ld hl, $c096
+ add hl, bc
+ ld [hl], d
+ ld hl, $c09e
+ add hl, bc
+ ld [hl], e
+ ld hl, $c0b6
+ add hl, bc
+ ld a, [hl]
+ ld hl, $c076
+ add hl, bc
+ sub [hl]
+ jr nc, .asm_97a7
+ ld a, $1
+.asm_97a7
+ ld [hl], a
+ ld hl, $c0ae
+ add hl, bc
+ ld a, e
+ sub [hl]
+ ld e, a
+ ld a, d
+ sbc b
+ ld hl, $c0a6
+ add hl, bc
+ sub [hl]
+ jr c, .asm_97c3
+ ld d, a
+ ld b, $0
+ ld hl, $c02e
+ add hl, bc
+ set 5, [hl]
+ jr .asm_97e6
+.asm_97c3
+ ld hl, $c096
+ add hl, bc
+ ld d, [hl]
+ ld hl, $c09e
+ add hl, bc
+ ld e, [hl]
+ ld hl, $c0ae
+ add hl, bc
+ ld a, [hl]
+ sub e
+ ld e, a
+ ld a, d
+ sbc b
+ ld d, a
+ ld hl, $c0a6
+ add hl, bc
+ ld a, [hl]
+ sub d
+ ld d, a
+ ld b, $0
+ ld hl, $c02e
+ add hl, bc
+ res 5, [hl]
+.asm_97e6
+ ld hl, $c076
+ add hl, bc
+.asm_97ea
+ inc b
+ ld a, e
+ sub [hl]
+ ld e, a
+ jr nc, .asm_97ea
+ ld a, d
+ and a
+ jr z, .asm_97f8
+ dec a
+ ld d, a
+ jr .asm_97ea
+.asm_97f8
+ ld a, e
+ add [hl]
+ ld d, b
+ ld b, $0
+ ld hl, $c07e
+ add hl, bc
+ ld [hl], d
+ ld hl, $c086
+ add hl, bc
+ ld [hl], a
+ ld hl, $c08e
+ add hl, bc
+ ld [hl], a
+ ret
+
+Music2_ApplyDutyCycle: ; 0x980d
+ ld b, $0
+ ld hl, $c046
+ add hl, bc
+ ld a, [hl]
+ rlca
+ rlca
+ ld [hl], a
+ and $c0
+ ld d, a
+ ld b, $1
+ call Func_9838
+ ld a, [hl]
+ and $3f
+ or d
+ ld [hl], a
+ ret
+
+Music2_GetNextMusicByte: ; 0x9825
+ ld d, $0
+ ld a, c
+ add a
+ ld e, a
+ ld hl, $c006
+ add hl, de
+ ld a, [hli]
+ ld e, a
+ ld a, [hld]
+ ld d, a
+ ld a, [de] ; get next music command
+ inc de
+ ld [hl], e ; store address of next command
+ inc hl
+ ld [hl], d
+ ret
+
+Func_9838: ; 0x9838
+ ld a, c
+ ld hl, Unknown_9b17
+ add l
+ jr nc, .noCarry
+ inc h
+.noCarry
+ ld l, a
+ ld a, [hl]
+ add b
+ ld l, a
+ ld h, $ff
+ ret
+
+Func_9847: ; 0x9847
+ ld h, $0
+.loop
+ srl a
+ jr nc, .noCarry
+ add hl, de
+.noCarry
+ sla e
+ rl d
+ and a
+ jr z, .done
+ jr .loop
+.done
+ ret
+
+Func_9858: ; 0x9858
+ ld h, $0
+ ld l, a
+ add hl, hl
+ ld d, h
+ ld e, l
+ ld hl, Unknown_9b2f
+ add hl, de
+ ld e, [hl]
+ inc hl
+ ld d, [hl]
+ ld a, b
+.loop
+ cp $7
+ jr z, .done
+ sra d
+ rr e
+ inc a
+ jr .loop
+.done
+ ld a, $8
+ add d
+ ld d, a
+ ret
+
+Func_9876: ; 0x9876
+ ld [$c001], a
+ cp $ff
+ jp z, Func_9a34
+ cp $b9
+ jp z, Func_994e
+ jp c, Func_994e
+ cp $fe
+ jr z, .asm_988d
+ jp nc, Func_994e
+.asm_988d
+ xor a
+ ld [$c000], a
+ ld [$c003], a
+ ld [$c0e9], a
+ ld [$c0e6], a
+ ld [$c0e7], a
+ ld d, $8
+ ld hl, $c016
+ call FillMusicRAM2
+ ld hl, $c006
+ call FillMusicRAM2
+ ld d, $4
+ ld hl, $c026
+ call FillMusicRAM2
+ ld hl, $c02e
+ call FillMusicRAM2
+ ld hl, $c03e
+ call FillMusicRAM2
+ ld hl, $c046
+ call FillMusicRAM2
+ ld hl, $c04e
+ call FillMusicRAM2
+ ld hl, $c056
+ call FillMusicRAM2
+ ld hl, $c05e
+ call FillMusicRAM2
+ ld hl, $c066
+ call FillMusicRAM2
+ ld hl, $c06e
+ call FillMusicRAM2
+ ld hl, $c036
+ call FillMusicRAM2
+ ld hl, $c076
+ call FillMusicRAM2
+ ld hl, $c07e
+ call FillMusicRAM2
+ ld hl, $c086
+ call FillMusicRAM2
+ ld hl, $c08e
+ call FillMusicRAM2
+ ld hl, $c096
+ call FillMusicRAM2
+ ld hl, $c09e
+ call FillMusicRAM2
+ ld hl, $c0a6
+ call FillMusicRAM2
+ ld hl, $c0ae
+ call FillMusicRAM2
+ ld a, $1
+ ld hl, $c0be
+ call FillMusicRAM2
+ ld hl, $c0b6
+ call FillMusicRAM2
+ ld hl, $c0c6
+ call FillMusicRAM2
+ ld [$c0e8], a
+ ld a, $ff
+ ld [$c004], a
+ xor a
+ ld [$ff00+$24], a
+ ld a, $8
+ ld [$ff00+$10], a
+ ld a, $0
+ ld [$ff00+$25], a
+ xor a
+ ld [$ff00+$1a], a
+ ld a, $80
+ ld [$ff00+$1a], a
+ ld a, $77
+ ld [$ff00+$24], a
+ jp Func_9a8f
+
+Func_994e: ; 0x994e
+ ld l, a
+ ld e, a
+ ld h, $0
+ ld d, h
+ add hl, hl
+ add hl, de
+ ld de, SFX_Headers_02
+ add hl, de
+ ld a, h
+ ld [$c0ec], a
+ ld a, l
+ ld [$c0ed], a
+ ld a, [hl]
+ and $c0
+ rlca
+ rlca
+ ld c, a
+.asm_9967
+ ld d, c
+ ld a, c
+ add a
+ add c
+ ld c, a
+ ld b, $0
+ ld a, [$c0ec]
+ ld h, a
+ ld a, [$c0ed]
+ ld l, a
+ add hl, bc
+ ld c, d
+ ld a, [hl]
+ and $f
+ ld e, a
+ ld d, $0
+ ld hl, $c026
+ add hl, de
+ ld a, [hl]
+ and a
+ jr z, .asm_99a3
+ ld a, e
+ cp $7
+ jr nz, .asm_999a
+ ld a, [$c001]
+ cp $14
+ jr nc, .asm_9993
+ ret
+.asm_9993
+ ld a, [hl]
+ cp $14
+ jr z, .asm_99a3
+ jr c, .asm_99a3
+.asm_999a
+ ld a, [$c001]
+ cp [hl]
+ jr z, .asm_99a3
+ jr c, .asm_99a3
+ ret
+.asm_99a3
+ xor a
+ push de
+ ld h, d
+ ld l, e
+ add hl, hl
+ ld d, h
+ ld e, l
+ ld hl, $c016
+ add hl, de
+ ld [hli], a
+ ld [hl], a
+ ld hl, $c006
+ add hl, de
+ ld [hli], a
+ ld [hl], a
+ pop de
+ ld hl, $c026
+ add hl, de
+ ld [hl], a
+ ld hl, $c02e
+ add hl, de
+ ld [hl], a
+ ld hl, $c03e
+ add hl, de
+ ld [hl], a
+ ld hl, $c046
+ add hl, de
+ ld [hl], a
+ ld hl, $c04e
+ add hl, de
+ ld [hl], a
+ ld hl, $c056
+ add hl, de
+ ld [hl], a
+ ld hl, $c05e
+ add hl, de
+ ld [hl], a
+ ld hl, $c066
+ add hl, de
+ ld [hl], a
+ ld hl, $c06e
+ add hl, de
+ ld [hl], a
+ ld hl, $c076
+ add hl, de
+ ld [hl], a
+ ld hl, $c07e
+ add hl, de
+ ld [hl], a
+ ld hl, $c086
+ add hl, de
+ ld [hl], a
+ ld hl, $c08e
+ add hl, de
+ ld [hl], a
+ ld hl, $c096
+ add hl, de
+ ld [hl], a
+ ld hl, $c09e
+ add hl, de
+ ld [hl], a
+ ld hl, $c0a6
+ add hl, de
+ ld [hl], a
+ ld hl, $c0ae
+ add hl, de
+ ld [hl], a
+ ld hl, $c036
+ add hl, de
+ ld [hl], a
+ ld a, $1
+ ld hl, $c0be
+ add hl, de
+ ld [hl], a
+ ld hl, $c0b6
+ add hl, de
+ ld [hl], a
+ ld hl, $c0c6
+ add hl, de
+ ld [hl], a
+ ld a, e
+ cp $4
+ jr nz, .asm_9a2b
+ ld a, $8
+ ld [$ff00+$10], a
+.asm_9a2b
+ ld a, c
+ and a
+ jp z, Func_9a8f
+ dec c
+ jp .asm_9967
+
+Func_9a34: ; 0x9a34
+ ld a, $80
+ ld [$ff00+$26], a
+ ld [$ff00+$1a], a
+ xor a
+ ld [$ff00+$25], a
+ ld [$ff00+$1c], a
+ ld a, $8
+ ld [$ff00+$10], a
+ ld [$ff00+$12], a
+ ld [$ff00+$17], a
+ ld [$ff00+$21], a
+ ld a, $40
+ ld [$ff00+$14], a
+ ld [$ff00+$19], a
+ ld [$ff00+$23], a
+ ld a, $77
+ ld [$ff00+$24], a
+ xor a
+ ld [$c000], a
+ ld [$c003], a
+ ld [$c002], a
+ ld [$c0e9], a
+ ld [$c0eb], a
+ ld [$c0e6], a
+ ld [$c0e7], a
+ ld d, $a0
+ ld hl, $c006
+ call FillMusicRAM2
+ ld a, $1
+ ld d, $18
+ ld hl, $c0b6
+ call FillMusicRAM2
+ ld [$c0e8], a
+ ld [$c0ea], a
+ ld a, $ff
+ ld [$c004], a
+ ret
+
+; fills d bytes at hl with a
+FillMusicRAM2: ; 0x9a89
+ ld b, d
+.loop
+ ld [hli], a
+ dec b
+ jr nz, .loop
+ ret
+
+Func_9a8f: ; 0x9a8f
+ ld a, [$c001]
+ ld l, a
+ ld e, a
+ ld h, $0
+ ld d, h
+ add hl, hl
+ add hl, de
+ ld de, SFX_Headers_02
+ add hl, de
+ ld e, l
+ ld d, h
+ ld hl, $c006
+ ld a, [de] ; get channel number
+ ld b, a
+ rlca
+ rlca
+ and $3
+ ld c, a
+ ld a, b
+ and $f
+ ld b, c
+ inc b
+ inc de
+ ld c, $0
+.asm_9ab1
+ cp c
+ jr z, .asm_9ab9
+ inc c
+ inc hl
+ inc hl
+ jr .asm_9ab1
+.asm_9ab9
+ push hl
+ push bc
+ push af
+ ld b, $0
+ ld c, a
+ ld hl, $c026
+ add hl, bc
+ ld a, [$c001]
+ ld [hl], a
+ pop af
+ cp $3
+ jr c, .asm_9ad2
+ ld hl, $c02e
+ add hl, bc
+ set 2, [hl]
+.asm_9ad2
+ pop bc
+ pop hl
+ ld a, [de] ; get channel pointer
+ ld [hli], a
+ inc de
+ ld a, [de]
+ ld [hli], a
+ inc de
+ inc c
+ dec b
+ ld a, b
+ and a
+ ld a, [de]
+ inc de
+ jr nz, .asm_9ab1
+ ld a, [$c001]
+ cp $14
+ jr nc, .asm_9aeb
+ jr .asm_9b15
+.asm_9aeb
+ ld a, [$c001]
+ cp $86
+ jr z, .asm_9b15
+ jr c, .asm_9af6
+ jr .asm_9b15
+.asm_9af6
+ ld hl, $c02a
+ ld [hli], a
+ ld [hli], a
+ ld [hli], a
+ ld [hl], a
+ ld hl, $c012 ; sfx noise channel pointer
+ ld de, Noise2_endchannel
+ ld [hl], e
+ inc hl
+ ld [hl], d ; overwrite pointer to point to endchannel
+ ld a, [$c005]
+ and a
+ jr nz, .asm_9b15
+ ld a, [$ff00+$24]
+ ld [$c005], a
+ ld a, $77
+ ld [$ff00+$24], a
+.asm_9b15
+ ret
+
+Noise2_endchannel: ; 0x9b16
+ endchannel
+
+Unknown_9b17: ; 0x9b17
+ db $10, $15, $1A, $1F ; channels 0-3
+ db $10, $15, $1A, $1F ; channels 4-7
+
+Unknown_9b1f: ; 0x9b1f
+ db $EE, $DD, $BB, $77 ; channels 0-3
+ db $EE, $DD, $BB, $77 ; channels 4-7
+
+Unknown_9b27: ; 0x9b27
+ db $11, $22, $44, $88 ; channels 0-3
+ db $11, $22, $44, $88 ; channels 4-7
+
+Unknown_9b2f: ; 0x9b2f
+ dw $F82C
+ dw $F89D
+ dw $F907
+ dw $F96B
+ dw $F9CA
+ dw $FA23
+ dw $FA77
+ dw $FAC7
+ dw $FB12
+ dw $FB58
+ dw $FB9B
+ dw $FBDA
+
+
diff --git a/audio/engine_2.asm b/audio/engine_2.asm
new file mode 100644
index 00000000..deb65357
--- /dev/null
+++ b/audio/engine_2.asm
@@ -0,0 +1,1733 @@
+; The second of three duplicated sound engines.
+
+Func_21879: ; 21879 (8:5879)
+ ld c, CH0
+.loop
+ ld b, $0
+ ld hl, $c026
+ add hl, bc
+ ld a, [hl]
+ and a
+ jr z, .nextChannel
+ ld a, c
+ cp CH4
+ jr nc, .applyAffects ; if sfx channel
+ ld a, [$c002]
+ and a
+ jr z, .applyAffects
+ bit 7, a
+ jr nz, .nextChannel
+ set 7, a
+ ld [$c002], a
+ xor a
+ ld [$FF00+$25], a
+ ld [$FF00+$1a], a
+ ld a, $80
+ ld [$FF00+$1a], a
+ jr .nextChannel
+.applyAffects
+ call Music8_ApplyMusicAffects
+.nextChannel
+ ld a, c
+ inc c
+ cp CH7
+ jr nz, .loop
+ ret
+
+; this routine checks flags for music effects currently applied
+; to the channel and calls certain functions based on flags.
+; known flags for $c02e:
+; 1: call has been used
+; 3: a toggle used only by this routine for vibrato
+; 4: pitchbend flag
+; 6: dutycycle flag
+Music8_ApplyMusicAffects: ; 218ae (8:58ae)
+ ld b, $0
+ ld hl, $c0b6 ; delay unitl next note
+ add hl, bc
+ ld a, [hl]
+ cp $1 ; if the delay is 1, play next note
+ jp z, Music8_PlayNextNote
+ dec a ; otherwise, decrease the delay timer
+ ld [hl], a
+ ld a, c
+ cp CH4
+ jr nc, .startChecks ; if a sfx channel
+ ld hl, $c02a
+ add hl, bc
+ ld a, [hl]
+ and a
+ jr z, .startChecks
+ ret
+.startChecks
+ ld hl, $c02e
+ add hl, bc
+ bit 6, [hl] ; dutycycle
+ jr z, .checkForExecuteMusic
+ call Music8_ApplyDutyCycle
+.checkForExecuteMusic
+ ld b, $0
+ ld hl, $c036
+ add hl, bc
+ bit 0, [hl]
+ jr nz, .checkForPitchBend
+ ld hl, $c02e
+ add hl, bc
+ bit 2, [hl]
+ jr nz, .disablePitchBendVibrato
+.checkForPitchBend
+ ld hl, $c02e
+ add hl, bc
+ bit 4, [hl] ; pitchbend
+ jr z, .checkVibratoDelay
+ jp Music8_ApplyPitchBend
+.checkVibratoDelay
+ ld hl, $c04e ; vibrato delay
+ add hl, bc
+ ld a, [hl]
+ and a ; check if delay is over
+ jr z, .checkForVibrato
+ dec [hl] ; otherwise, dec delay
+.disablePitchBendVibrato
+ ret
+.checkForVibrato
+ ld hl, $c056 ; vibrato rate
+ add hl, bc
+ ld a, [hl]
+ and a
+ jr nz, .vibrato
+ ret ; no vibrato
+.vibrato
+ ld d, a
+ ld hl, $c05e
+ add hl, bc
+ ld a, [hl]
+ and $f
+ and a
+ jr z, .vibratoAlreadyDone
+ dec [hl] ; apply vibrato pitch change
+ ret
+.vibratoAlreadyDone
+ ld a, [hl]
+ swap [hl]
+ or [hl]
+ ld [hl], a ; reset the vibrato value and start again
+ ld hl, $c066
+ add hl, bc
+ ld e, [hl] ; get note pitch
+ ld hl, $c02e
+ add hl, bc
+ bit 3, [hl] ; this is the only code that sets/resets bit three so
+ jr z, .unset ; it continuously alternates which path it takes
+ res 3, [hl]
+ ld a, d
+ and $f
+ ld d, a
+ ld a, e
+ sub d
+ jr nc, .noCarry
+ ld a, $0
+.noCarry
+ jr .done
+.unset
+ set 3, [hl]
+ ld a, d
+ and $f0
+ swap a
+ add e
+ jr nc, .done
+ ld a, $ff
+.done
+ ld d, a
+ ld b, $3
+ call Func_21ff7
+ ld [hl], d
+ ret
+
+; this routine executes all music commands that take up no time,
+; like tempo changes, duty changes etc. and doesn't return
+; until the first note is reached
+Music8_PlayNextNote: ; 21946 (8:5946)
+ ld hl, $c06e
+ add hl, bc
+ ld a, [hl]
+ ld hl, $c04e
+ add hl, bc
+ ld [hl], a
+ ld hl, $c02e
+ add hl, bc
+ res 4, [hl]
+ res 5, [hl]
+ ld a, c
+ cp CH4
+ jr nz, .beginChecks
+ ld a, [$d083]
+ bit 7, a
+ ret nz
+.beginChecks
+ call Music8_endchannel
+ ret
+
+Music8_endchannel: ; 21967 (8:5967)
+ call Music8_GetNextMusicByte
+ ld d, a
+ cp $ff ; is this command an endchannel?
+ jp nz, Music8_callchannel ; no
+ ld b, $0 ; yes
+ ld hl, $c02e
+ add hl, bc
+ bit 1, [hl]
+ jr nz, .returnFromCall
+ ld a, c
+ cp CH3
+ jr nc, .noiseOrSfxChannel
+ jr .asm_219c0
+.noiseOrSfxChannel
+ res 2, [hl]
+ ld hl, $c036
+ add hl, bc
+ res 0, [hl]
+ cp CH6
+ jr nz, .notSfxChannel3
+ ld a, $0
+ ld [$FF00+$1a], a
+ ld a, $80
+ ld [$FF00+$1a], a
+.notSfxChannel3
+ jr nz, .asm_219a3
+ ld a, [$c003]
+ and a
+ jr z, .asm_219a3
+ xor a
+ ld [$c003], a
+ jr .asm_219c0
+.asm_219a3
+ jr .asm_219c9
+.returnFromCall
+ res 1, [hl]
+ ld d, $0
+ ld a, c
+ add a
+ ld e, a
+ ld hl, $c006
+ add hl, de
+ push hl ; store current channel address
+ ld hl, $c016
+ add hl, de
+ ld e, l
+ ld d, h
+ pop hl
+ ld a, [de]
+ ld [hli], a
+ inc de
+ ld a, [de]
+ ld [hl], a ; loads channel address to return to
+ jp Music8_endchannel
+.asm_219c0
+ ld hl, Unknown_222de
+ add hl, bc
+ ld a, [$FF00+$25]
+ and [hl]
+ ld [$FF00+$25], a
+.asm_219c9
+ ld a, [$c02a]
+ cp $14
+ jr nc, .asm_219d2
+ jr .asm_219ef
+.asm_219d2
+ ld a, [$c02a]
+ cp $86
+ jr z, .asm_219ef
+ jr c, .asm_219dd
+ jr .asm_219ef
+.asm_219dd
+ ld a, c
+ cp CH4
+ jr z, .asm_219e6
+ call Func_21e6d
+ ret c
+.asm_219e6
+ ld a, [$c005]
+ ld [$FF00+$24], a
+ xor a
+ ld [$c005], a
+.asm_219ef
+ ld hl, $c026
+ add hl, bc
+ ld [hl], b
+ ret
+
+Music8_callchannel: ; 219f5 (8:59f5)
+ cp $fd ; is this command a callchannel?
+ jp nz, Music8_loopchannel ; no
+ call Music8_GetNextMusicByte ; yes
+ push af
+ call Music8_GetNextMusicByte
+ ld d, a
+ pop af
+ ld e, a
+ push de ; store pointer
+ ld d, $0
+ ld a, c
+ add a
+ ld e, a
+ ld hl, $c006
+ add hl, de
+ push hl
+ ld hl, $c016
+ add hl, de
+ ld e, l
+ ld d, h
+ pop hl
+ ld a, [hli]
+ ld [de], a
+ inc de
+ ld a, [hld]
+ ld [de], a ; copy current channel address
+ pop de
+ ld [hl], e
+ inc hl
+ ld [hl], d ; overwrite current address with pointer
+ ld b, $0
+ ld hl, $c02e
+ add hl, bc
+ set 1, [hl] ; set the call flag
+ jp Music8_endchannel
+
+Music8_loopchannel: ; 21a2a (8:5a2a)
+ cp $fe ; is this command a loopchannel?
+ jp nz, Music8_notetype ; no
+ call Music8_GetNextMusicByte ; yes
+ ld e, a
+ and a
+ jr z, .infiniteLoop
+ ld b, $0
+ ld hl, $c0be
+ add hl, bc
+ ld a, [hl]
+ cp e
+ jr nz, .loopAgain
+ ld a, $1 ; if no more loops to make,
+ ld [hl], a
+ call Music8_GetNextMusicByte ; skip pointer
+ call Music8_GetNextMusicByte
+ jp Music8_endchannel
+.loopAgain ; inc loop count
+ inc a
+ ld [hl], a
+ ; fall through
+.infiniteLoop ; overwrite current address with pointer
+ call Music8_GetNextMusicByte
+ push af
+ call Music8_GetNextMusicByte
+ ld b, a
+ ld d, $0
+ ld a, c
+ add a
+ ld e, a
+ ld hl, $c006
+ add hl, de
+ pop af
+ ld [hli], a
+ ld [hl], b
+ jp Music8_endchannel
+
+Music8_notetype: ; 21a65 (8:5a65)
+ and $f0
+ cp $d0 ; is this command a notetype?
+ jp nz, Music8_togglecall ; no
+ ld a, d ; yes
+ and $f
+ ld b, $0
+ ld hl, $c0c6
+ add hl, bc
+ ld [hl], a ; store low nibble as speed
+ ld a, c
+ cp CH3
+ jr z, .noiseChannel ; noise channel has 0 params
+ call Music8_GetNextMusicByte
+ ld d, a
+ ld a, c
+ cp CH2
+ jr z, .musicChannel3
+ cp CH6
+ jr nz, .notChannel3
+ ld hl, $c0e7
+ jr .sfxChannel3
+.musicChannel3
+ ld hl, $c0e6
+.sfxChannel3
+ ld a, d
+ and $f
+ ld [hl], a ; store low nibble of param as duty
+ ld a, d
+ and $30
+ sla a
+ ld d, a
+ ; fall through
+
+ ; if channel 3, store high nibble as volume
+ ; else, store volume (high nibble) and fade (low nibble)
+.notChannel3
+ ld b, $0
+ ld hl, $c0de
+ add hl, bc
+ ld [hl], d
+.noiseChannel
+ jp Music8_endchannel
+
+Music8_togglecall: ; 21aa4 (8:5aa4)
+ ld a, d
+ cp $e8 ; is this command an togglecall?
+ jr nz, Music8_vibrato ; no
+ ld b, $0 ; yes
+ ld hl, $c02e
+ add hl, bc
+ ld a, [hl]
+ xor $1
+ ld [hl], a ; flip bit 0 of $c02e (toggle returning from call)
+ jp Music8_endchannel
+
+Music8_vibrato: ; 21ab6 (8:5ab6)
+ cp $ea ; is this command a vibrato?
+ jr nz, Music8_pitchbend ; no
+ call Music8_GetNextMusicByte ; yes
+ ld b, $0
+ ld hl, $c04e
+ add hl, bc
+ ld [hl], a ; store delay
+ ld hl, $c06e
+ add hl, bc
+ ld [hl], a ; store delay
+ call Music8_GetNextMusicByte
+ ld d, a
+ and $f0
+ swap a
+ ld b, $0
+ ld hl, $c056
+ add hl, bc
+ srl a
+ ld e, a
+ adc b
+ swap a
+ or e
+ ld [hl], a ; store rate as both high and low nibbles
+ ld a, d
+ and $f
+ ld d, a
+ ld hl, $c05e
+ add hl, bc
+ swap a
+ or d
+ ld [hl], a ; store depth as both high and low nibbles
+ jp Music8_endchannel
+
+Music8_pitchbend: ; 21aee (8:5aee)
+ cp $eb ; is this command a pitchbend?
+ jr nz, Music8_duty ; no
+ call Music8_GetNextMusicByte ; yes
+ ld b, $0
+ ld hl, $c076
+ add hl, bc
+ ld [hl], a ; store first param
+ call Music8_GetNextMusicByte
+ ld d, a
+ and $f0
+ swap a
+ ld b, a
+ ld a, d
+ and $f
+ call Func_22017
+ ld b, $0
+ ld hl, $c0a6
+ add hl, bc
+ ld [hl], d ; store unknown part of second param
+ ld hl, $c0ae
+ add hl, bc
+ ld [hl], e ; store unknown part of second param
+ ld b, $0
+ ld hl, $c02e
+ add hl, bc
+ set 4, [hl] ; set pitchbend flag
+ call Music8_GetNextMusicByte
+ ld d, a
+ jp Music8_notelength
+
+Music8_duty: ; 21b26 (8:5b26)
+ cp $ec ; is this command a duty?
+ jr nz, Music8_tempo ; no
+ call Music8_GetNextMusicByte ; yes
+ rrca
+ rrca
+ and $c0
+ ld b, $0
+ ld hl, $c03e
+ add hl, bc
+ ld [hl], a ; store duty
+ jp Music8_endchannel
+
+Music8_tempo: ; 21b3b (8:5b3b)
+ cp $ed ; is this command a tempo?
+ jr nz, Music8_unknownmusic0xee ; no
+ ld a, c ; yes
+ cp CH4
+ jr nc, .sfxChannel
+ call Music8_GetNextMusicByte
+ ld [$c0e8], a ; store first param
+ call Music8_GetNextMusicByte
+ ld [$c0e9], a ; store second param
+ xor a
+ ld [$c0ce], a ; clear RAM
+ ld [$c0cf], a
+ ld [$c0d0], a
+ ld [$c0d1], a
+ jr .musicChannelDone
+.sfxChannel
+ call Music8_GetNextMusicByte
+ ld [$c0ea], a ; store first param
+ call Music8_GetNextMusicByte
+ ld [$c0eb], a ; store second param
+ xor a
+ ld [$c0d2], a ; clear RAM
+ ld [$c0d3], a
+ ld [$c0d4], a
+ ld [$c0d5], a
+.musicChannelDone
+ jp Music8_endchannel
+
+Music8_unknownmusic0xee: ; 21b7b (8:5b7b)
+ cp $ee ; is this command an unknownmusic0xee?
+ jr nz, Music8_unknownmusic0xef ; no
+ call Music8_GetNextMusicByte ; yes
+ ld [$c004], a ; store first param
+ jp Music8_endchannel
+
+; this appears to never be used
+Music8_unknownmusic0xef: ; 21b88 (8:5b88)
+ cp $ef ; is this command an unknownmusic0xef?
+ jr nz, Music8_dutycycle ; no
+ call Music8_GetNextMusicByte ; yes
+ push bc
+ call Func_22035
+ pop bc
+ ld a, [$c003]
+ and a
+ jr nz, .skip
+ ld a, [$c02d]
+ ld [$c003], a
+ xor a
+ ld [$c02d], a
+.skip
+ jp Music8_endchannel
+
+Music8_dutycycle: ; 21ba7 (8:5ba7)
+ cp $fc ; is this command a dutycycle?
+ jr nz, Music8_stereopanning ; no
+ call Music8_GetNextMusicByte ; yes
+ ld b, $0
+ ld hl, $c046
+ add hl, bc
+ ld [hl], a ; store full cycle
+ and $c0
+ ld hl, $c03e
+ add hl, bc
+ ld [hl], a ; store first duty
+ ld hl, $c02e
+ add hl, bc
+ set 6, [hl] ; set dutycycle flag
+ jp Music8_endchannel
+
+Music8_stereopanning: ; 21bc5 (8:5bc5)
+ cp $f0 ; is this command a stereopanning?
+ jr nz, Music8_executemusic ; no
+ call Music8_GetNextMusicByte ; yes
+ ld [$FF00+$24], a
+ jp Music8_endchannel
+
+Music8_executemusic: ; 21bd1 (8:5bd1)
+ cp $f8 ; is this command an executemusic?
+ jr nz, Music8_octave ; no
+ ld b, $0 ; yes
+ ld hl, $c036
+ add hl, bc
+ set 0, [hl]
+ jp Music8_endchannel
+
+Music8_octave: ; 21be0 (8:5be0)
+ and $f0
+ cp $e0 ; is this command an octave?
+ jr nz, Music8_unknownsfx0x20 ; no
+ ld hl, $c0d6 ; yes
+ ld b, $0
+ add hl, bc
+ ld a, d
+ and $f
+ ld [hl], a ; store low nibble as octave
+ jp Music8_endchannel
+
+Music8_unknownsfx0x20: ; 21bf3
+ cp $20 ; is this command an unknownsfx0x20?
+ jr nz, Music8_unknownsfx0x10 ; no
+ ld a, c
+ cp CH3 ; is this a noise or sfx channel?
+ jr c, Music8_unknownsfx0x10 ; no
+ ld b, $0
+ ld hl, $c036
+ add hl, bc
+ bit 0, [hl]
+ jr nz, Music8_unknownsfx0x10 ; no
+ call Music8_notelength
+ ld d, a
+ ld b, $0
+ ld hl, $c03e
+ add hl, bc
+ ld a, [hl]
+ or d
+ ld d, a
+ ld b, $1
+ call Func_21ff7
+ ld [hl], d
+ call Music8_GetNextMusicByte
+ ld d, a
+ ld b, $2
+ call Func_21ff7
+ ld [hl], d
+ call Music8_GetNextMusicByte
+ ld e, a
+ ld a, c
+ cp CH7
+ ld a, $0
+ jr z, .sfxNoiseChannel ; only two params for noise channel
+ push de
+ call Music8_GetNextMusicByte
+ pop de
+.sfxNoiseChannel
+ ld d, a
+ push de
+ call Func_21daa
+ call Func_21d79
+ pop de
+ call Func_21dcc
+ ret
+
+Music8_unknownsfx0x10: ; 21c40 (8:5c40)
+ ld a, c
+ cp CH4
+ jr c, Music8_note ; if not a sfx
+ ld a, d
+ cp $10 ; is this command a unknownsfx0x10?
+ jr nz, Music8_note ; no
+ ld b, $0
+ ld hl, $c036
+ add hl, bc
+ bit 0, [hl]
+ jr nz, Music8_note ; no
+ call Music8_GetNextMusicByte ; yes
+ ld [$FF00+$10], a
+ jp Music8_endchannel
+
+Music8_note: ; 21c5c (8:5c5c)
+ ld a, c
+ cp CH3
+ jr nz, Music8_notelength ; if not noise channel
+ ld a, d
+ and $f0
+ cp $b0 ; is this command a dnote?
+ jr z, Music8_dnote ; yes
+ jr nc, Music8_notelength ; no
+ swap a
+ ld b, a
+ ld a, d
+ and $f
+ ld d, a
+ ld a, b
+ push de
+ push bc
+ jr asm_21c7e
+
+Music8_dnote: ; 21c76 (8:5c76)
+ ld a, d
+ and $f
+ push af
+ push bc
+ call Music8_GetNextMusicByte ; get dnote instrument
+asm_21c7e
+ ld d, a
+ ld a, [$c003]
+ and a
+ jr nz, .asm_21c89
+ ld a, d
+ call Func_22035
+.asm_21c89
+ pop bc
+ pop de
+
+Music8_notelength: ; 21c8b (8:5c8b)
+ ld a, d
+ push af
+ and $f
+ inc a
+ ld b, $0
+ ld e, a ; store note length (in 16ths)
+ ld d, b
+ ld hl, $c0c6
+ add hl, bc
+ ld a, [hl]
+ ld l, b
+ call Func_22006
+ ld a, c
+ cp CH4
+ jr nc, .sfxChannel
+ ld a, [$c0e8]
+ ld d, a
+ ld a, [$c0e9]
+ ld e, a
+ jr .skip
+.sfxChannel
+ ld d, $1
+ ld e, $0
+ cp CH7
+ jr z, .skip ; if noise channel
+ call Func_21e2f
+ ld a, [$c0ea]
+ ld d, a
+ ld a, [$c0eb]
+ ld e, a
+.skip
+ ld a, l
+ ld b, $0
+ ld hl, $c0ce
+ add hl, bc
+ ld l, [hl]
+ call Func_22006
+ ld e, l
+ ld d, h
+ ld hl, $c0ce
+ add hl, bc
+ ld [hl], e
+ ld a, d
+ ld hl, $c0b6
+ add hl, bc
+ ld [hl], a
+ ld hl, $c036
+ add hl, bc
+ bit 0, [hl]
+ jr nz, Music8_notepitch
+ ld hl, $c02e
+ add hl, bc
+ bit 2, [hl]
+ jr z, Music8_notepitch
+ pop hl
+ ret
+
+Music8_notepitch: ; 21ce9 (8:5ce9)
+ pop af
+ and $f0
+ cp $c0 ; compare to rest
+ jr nz, .notRest
+ ld a, c
+ cp CH4
+ jr nc, .sfxChannel
+ ld hl, $c02a
+ add hl, bc
+ ld a, [hl]
+ and a
+ jr nz, .done
+ ; fall through
+.sfxChannel
+ ld a, c
+ cp CH2
+ jr z, .musicChannel3
+ cp CH6
+ jr nz, .notSfxChannel3
+.musicChannel3
+ ld b, $0
+ ld hl, Unknown_222de
+ add hl, bc
+ ld a, [$FF00+$25]
+ and [hl]
+ ld [$FF00+$25], a
+ jr .done
+.notSfxChannel3
+ ld b, $2
+ call Func_21ff7
+ ld a, $8
+ ld [hli], a
+ inc hl
+ ld a, $80
+ ld [hl], a
+.done
+ ret
+.notRest
+ swap a
+ ld b, $0
+ ld hl, $c0d6
+ add hl, bc
+ ld b, [hl]
+ call Func_22017
+ ld b, $0
+ ld hl, $c02e
+ add hl, bc
+ bit 4, [hl]
+ jr z, .asm_21d39
+ call Func_21f4e
+.asm_21d39
+ push de
+ ld a, c
+ cp CH4
+ jr nc, .skip ; if sfx channel
+ ld hl, $c02a
+ ld d, $0
+ ld e, a
+ add hl, de
+ ld a, [hl]
+ and a
+ jr nz, .asm_21d4c
+ jr .skip
+.asm_21d4c
+ pop de
+ ret
+.skip
+ ld b, $0
+ ld hl, $c0de
+ add hl, bc
+ ld d, [hl]
+ ld b, $2
+ call Func_21ff7
+ ld [hl], d
+ call Func_21daa
+ call Func_21d79
+ pop de
+ ld b, $0
+ ld hl, $c02e
+ add hl, bc
+ bit 0, [hl]
+ jr z, .asm_21d70
+ inc e
+ jr nc, .asm_21d70
+ inc d
+.asm_21d70
+ ld hl, $c066
+ add hl, bc
+ ld [hl], e
+ call Func_21dcc
+ ret
+
+Func_21d79: ; 21d79 (8:5d79)
+ ld b, $0
+ ld hl, Unknown_222e6
+ add hl, bc
+ ld a, [$FF00+$25]
+ or [hl]
+ ld d, a
+ ld a, c
+ cp CH7
+ jr z, .sfxNoiseChannel
+ cp CH4
+ jr nc, .skip ; if sfx channel
+ ld hl, $c02a
+ add hl, bc
+ ld a, [hl]
+ and a
+ jr nz, .skip
+.sfxNoiseChannel
+ ld a, [$c004]
+ ld hl, Unknown_222e6
+ add hl, bc
+ and [hl]
+ ld d, a
+ ld a, [$FF00+$25]
+ ld hl, Unknown_222de
+ add hl, bc
+ and [hl]
+ or d
+ ld d, a
+.skip
+ ld a, d
+ ld [$FF00+$25], a
+ ret
+
+Func_21daa: ; 21daa (8:5daa)
+ ld b, $0
+ ld hl, $c0b6
+ add hl, bc
+ ld d, [hl]
+ ld a, c
+ cp CH2
+ jr z, .channel3 ; if music channel 3
+ cp CH6
+ jr z, .channel3 ; if sfx channel 3
+ ld a, d
+ and $3f
+ ld d, a
+ ld hl, $c03e
+ add hl, bc
+ ld a, [hl]
+ or d
+ ld d, a
+.channel3
+ ld b, $1
+ call Func_21ff7
+ ld [hl], d
+ ret
+
+Func_21dcc: ; 21dcc (8:5dcc)
+ ld a, c
+ cp CH2
+ jr z, .channel3
+ cp CH6
+ jr nz, .notSfxChannel3
+ ; fall through
+.channel3
+ push de
+ ld de, $c0e6
+ cp CH2
+ jr z, .musicChannel3
+ ld de, $c0e7
+.musicChannel3
+ ld a, [de]
+ add a
+ ld d, $0
+ ld e, a
+ ld hl, Music8_Channel3DutyPointers
+ add hl, de
+ ld e, [hl]
+ inc hl
+ ld d, [hl]
+ ld hl, $ff30
+ ld b, $f
+ ld a, $0
+ ld [$FF00+$1a], a
+.loop
+ ld a, [de]
+ inc de
+ ld [hli], a
+ ld a, b
+ dec b
+ and a
+ jr nz, .loop
+ ld a, $80
+ ld [$FF00+$1a], a
+ pop de
+.notSfxChannel3
+ ld a, d
+ or $80
+ and $c7
+ ld d, a
+ ld b, $3
+ call Func_21ff7
+ ld [hl], e
+ inc hl
+ ld [hl], d
+ ld a, c
+ cp CH4
+ jr c, .musicChannel
+ call Func_21e56
+.musicChannel
+ ret
+
+Func_21e19: ; 21e19 (8:5e19)
+ ld a, c
+ cp CH4
+ jr nz, .asm_21e2e
+ ld a, [$d083]
+ bit 7, a
+ jr z, .asm_21e2e
+ xor a
+ ld [$c0f1], a
+ ld a, $80
+ ld [$c0f2], a
+.asm_21e2e
+ ret
+
+Func_21e2f: ; 21e2f (8:5e2f)
+ call Func_21e8b
+ jr c, .asm_21e39
+ call Func_21e9f
+ jr nc, .asm_21e4c
+.asm_21e39
+ ld d, $0
+ ld a, [$c0f2]
+ add $80
+ jr nc, .asm_21e43
+ inc d
+.asm_21e43
+ ld [$c0eb], a
+ ld a, d
+ ld [$c0ea], a
+ jr .asm_21e55
+.asm_21e4c
+ xor a
+ ld [$c0eb], a
+ ld a, $1
+ ld [$c0ea], a
+.asm_21e55
+ ret
+
+Func_21e56: ; 21e56 (8:5e56)
+ call Func_21e8b
+ jr c, .asm_21e60
+ call Func_21e9f
+ jr nc, .asm_21e6c
+.asm_21e60
+ ld a, [$c0f1]
+ add e
+ jr nc, .asm_21e67
+ inc d
+.asm_21e67
+ dec hl
+ ld e, a
+ ld [hl], e
+ inc hl
+ ld [hl], d
+.asm_21e6c
+ ret
+
+Func_21e6d: ; 21e6d (8:5e6d)
+ call Func_21e8b
+ jr nc, .asm_21e88
+ ld hl, $c006
+ ld e, c
+ ld d, $0
+ sla e
+ rl d
+ add hl, de
+ ld a, [hl]
+ sub $1
+ ld [hl], a
+ inc hl
+ ld a, [hl]
+ sbc $0
+ ld [hl], a
+ scf
+ ret
+.asm_21e88
+ scf
+ ccf
+ ret
+
+Func_21e8b: ; 21e8b (8:5e8b)
+ ld a, [$c02a]
+ cp $14
+ jr nc, .asm_21e94
+ jr .asm_21e9a
+.asm_21e94
+ cp $86
+ jr z, .asm_21e9a
+ jr c, .asm_21e9d
+.asm_21e9a
+ scf
+ ccf
+ ret
+.asm_21e9d
+ scf
+ ret
+
+Func_21e9f: ; 21e9f (8:5e9f)
+ ld a, [$c02d]
+ ld b, a
+ ld a, [$c02a]
+ or b
+ cp $9d
+ jr nc, .asm_21ead
+ jr .asm_21eb3
+.asm_21ead
+ cp $ea
+ jr z, .asm_21eb3
+ jr c, .asm_21eb6
+.asm_21eb3
+ scf
+ ccf
+ ret
+.asm_21eb6
+ scf
+ ret
+
+Music8_ApplyPitchBend: ; 21eb8 (8:5eb8)
+ ld hl, $c02e
+ add hl, bc
+ bit 5, [hl]
+ jp nz, .asm_21eff
+ ld hl, $c09e
+ add hl, bc
+ ld e, [hl]
+ ld hl, $c096
+ add hl, bc
+ ld d, [hl]
+ ld hl, $c07e
+ add hl, bc
+ ld l, [hl]
+ ld h, b
+ add hl, de
+ ld d, h
+ ld e, l
+ ld hl, $c08e
+ add hl, bc
+ push hl
+ ld hl, $c086
+ add hl, bc
+ ld a, [hl]
+ pop hl
+ add [hl]
+ ld [hl], a
+ ld a, $0
+ adc e
+ ld e, a
+ ld a, $0
+ adc d
+ ld d, a
+ ld hl, $c0a6
+ add hl, bc
+ ld a, [hl]
+ cp d
+ jp c, .asm_21f45
+ jr nz, .asm_21f32
+ ld hl, $c0ae
+ add hl, bc
+ ld a, [hl]
+ cp e
+ jp c, .asm_21f45
+ jr .asm_21f32
+.asm_21eff
+ ld hl, $c09e
+ add hl, bc
+ ld a, [hl]
+ ld hl, $c096
+ add hl, bc
+ ld d, [hl]
+ ld hl, $c07e
+ add hl, bc
+ ld e, [hl]
+ sub e
+ ld e, a
+ ld a, d
+ sbc b
+ ld d, a
+ ld hl, $c086
+ add hl, bc
+ ld a, [hl]
+ add a
+ ld [hl], a
+ ld a, e
+ sbc b
+ ld e, a
+ ld a, d
+ sbc b
+ ld d, a
+ ld hl, $c0a6
+ add hl, bc
+ ld a, d
+ cp [hl]
+ jr c, .asm_21f45
+ jr nz, .asm_21f32
+ ld hl, $c0ae
+ add hl, bc
+ ld a, e
+ cp [hl]
+ jr c, .asm_21f45
+.asm_21f32
+ ld hl, $c09e
+ add hl, bc
+ ld [hl], e
+ ld hl, $c096
+ add hl, bc
+ ld [hl], d
+ ld b, $3
+ call Func_21ff7
+ ld a, e
+ ld [hli], a
+ ld [hl], d
+ ret
+.asm_21f45
+ ld hl, $c02e
+ add hl, bc
+ res 4, [hl]
+ res 5, [hl]
+ ret
+
+Func_21f4e: ; 21f4e (8:5f4e)
+ ld hl, $c096
+ add hl, bc
+ ld [hl], d
+ ld hl, $c09e
+ add hl, bc
+ ld [hl], e
+ ld hl, $c0b6
+ add hl, bc
+ ld a, [hl]
+ ld hl, $c076
+ add hl, bc
+ sub [hl]
+ jr nc, .asm_21f66
+ ld a, $1
+.asm_21f66
+ ld [hl], a
+ ld hl, $c0ae
+ add hl, bc
+ ld a, e
+ sub [hl]
+ ld e, a
+ ld a, d
+ sbc b
+ ld hl, $c0a6
+ add hl, bc
+ sub [hl]
+ jr c, .asm_21f82
+ ld d, a
+ ld b, $0
+ ld hl, $c02e
+ add hl, bc
+ set 5, [hl]
+ jr .asm_21fa5
+.asm_21f82
+ ld hl, $c096
+ add hl, bc
+ ld d, [hl]
+ ld hl, $c09e
+ add hl, bc
+ ld e, [hl]
+ ld hl, $c0ae
+ add hl, bc
+ ld a, [hl]
+ sub e
+ ld e, a
+ ld a, d
+ sbc b
+ ld d, a
+ ld hl, $c0a6
+ add hl, bc
+ ld a, [hl]
+ sub d
+ ld d, a
+ ld b, $0
+ ld hl, $c02e
+ add hl, bc
+ res 5, [hl]
+.asm_21fa5
+ ld hl, $c076
+ add hl, bc
+.asm_21fa9
+ inc b
+ ld a, e
+ sub [hl]
+ ld e, a
+ jr nc, .asm_21fa9
+ ld a, d
+ and a
+ jr z, .asm_21fb7
+ dec a
+ ld d, a
+ jr .asm_21fa9
+.asm_21fb7
+ ld a, e
+ add [hl]
+ ld d, b
+ ld b, $0
+ ld hl, $c07e
+ add hl, bc
+ ld [hl], d
+ ld hl, $c086
+ add hl, bc
+ ld [hl], a
+ ld hl, $c08e
+ add hl, bc
+ ld [hl], a
+ ret
+
+Music8_ApplyDutyCycle: ; 21fcc (8:5fcc)
+ ld b, $0
+ ld hl, $c046
+ add hl, bc
+ ld a, [hl]
+ rlca
+ rlca
+ ld [hl], a
+ and $c0
+ ld d, a
+ ld b, $1
+ call Func_21ff7
+ ld a, [hl]
+ and $3f
+ or d
+ ld [hl], a
+ ret
+
+Music8_GetNextMusicByte: ; 21fe4 (8:5fe4)
+ ld d, $0
+ ld a, c
+ add a
+ ld e, a
+ ld hl, $c006
+ add hl, de
+ ld a, [hli]
+ ld e, a
+ ld a, [hld]
+ ld d, a
+ ld a, [de] ; get next music command
+ inc de
+ ld [hl], e ; store address of next command
+ inc hl
+ ld [hl], d
+ ret
+
+Func_21ff7: ; 21ff7 (8:5ff7)
+ ld a, c
+ ld hl, Unknown_222d6
+ add l
+ jr nc, .noCarry
+ inc h
+.noCarry
+ ld l, a
+ ld a, [hl]
+ add b
+ ld l, a
+ ld h, $ff
+ ret
+
+Func_22006: ; 22006 (8:6006)
+ ld h, $0
+.loop
+ srl a
+ jr nc, .noCarry
+ add hl, de
+.noCarry
+ sla e
+ rl d
+ and a
+ jr z, .done
+ jr .loop
+.done
+ ret
+
+Func_22017: ; 22017 (8:6017)
+ ld h, $0
+ ld l, a
+ add hl, hl
+ ld d, h
+ ld e, l
+ ld hl, Unknown_222ee
+ add hl, de
+ ld e, [hl]
+ inc hl
+ ld d, [hl]
+ ld a, b
+.loop
+ cp CH7
+ jr z, .done
+ sra d
+ rr e
+ inc a
+ jr .loop
+.done
+ ld a, $8
+ add d
+ ld d, a
+ ret
+
+Func_22035: ; 22035 (8:6035)
+ ld [$c001], a
+ cp $ff
+ jp z, Func_221f3
+ cp $e9
+ jp z, Func_2210d
+ jp c, Func_2210d
+ cp $fe
+ jr z, .asm_2204c
+ jp nc, Func_2210d
+.asm_2204c
+ xor a
+ ld [$c000], a
+ ld [$c003], a
+ ld [$c0e9], a
+ ld [$c0e6], a
+ ld [$c0e7], a
+ ld d, $8
+ ld hl, $c016
+ call FillMusicRAM8
+ ld hl, $c006
+ call FillMusicRAM8
+ ld d, $4
+ ld hl, $c026
+ call FillMusicRAM8
+ ld hl, $c02e
+ call FillMusicRAM8
+ ld hl, $c03e
+ call FillMusicRAM8
+ ld hl, $c046
+ call FillMusicRAM8
+ ld hl, $c04e
+ call FillMusicRAM8
+ ld hl, $c056
+ call FillMusicRAM8
+ ld hl, $c05e
+ call FillMusicRAM8
+ ld hl, $c066
+ call FillMusicRAM8
+ ld hl, $c06e
+ call FillMusicRAM8
+ ld hl, $c036
+ call FillMusicRAM8
+ ld hl, $c076
+ call FillMusicRAM8
+ ld hl, $c07e
+ call FillMusicRAM8
+ ld hl, $c086
+ call FillMusicRAM8
+ ld hl, $c08e
+ call FillMusicRAM8
+ ld hl, $c096
+ call FillMusicRAM8
+ ld hl, $c09e
+ call FillMusicRAM8
+ ld hl, $c0a6
+ call FillMusicRAM8
+ ld hl, $c0ae
+ call FillMusicRAM8
+ ld a, $1
+ ld hl, $c0be
+ call FillMusicRAM8
+ ld hl, $c0b6
+ call FillMusicRAM8
+ ld hl, $c0c6
+ call FillMusicRAM8
+ ld [$c0e8], a
+ ld a, $ff
+ ld [$c004], a
+ xor a
+ ld [$FF00+$24], a
+ ld a, $8
+ ld [$FF00+$10], a
+ ld a, $0
+ ld [$FF00+$25], a
+ xor a
+ ld [$FF00+$1a], a
+ ld a, $80
+ ld [$FF00+$1a], a
+ ld a, $77
+ ld [$FF00+$24], a
+ jp Func_2224e
+
+Func_2210d: ; 2210d (8:610d)
+ ld l, a
+ ld e, a
+ ld h, $0
+ ld d, h
+ add hl, hl
+ add hl, de
+ ld de, SFX_Headers_08
+ add hl, de
+ ld a, h
+ ld [$c0ec], a
+ ld a, l
+ ld [$c0ed], a
+ ld a, [hl]
+ and $c0
+ rlca
+ rlca
+ ld c, a
+.asm_22126
+ ld d, c
+ ld a, c
+ add a
+ add c
+ ld c, a
+ ld b, $0
+ ld a, [$c0ec]
+ ld h, a
+ ld a, [$c0ed]
+ ld l, a
+ add hl, bc
+ ld c, d
+ ld a, [hl]
+ and $f
+ ld e, a
+ ld d, $0
+ ld hl, $c026
+ add hl, de
+ ld a, [hl]
+ and a
+ jr z, .asm_22162
+ ld a, e
+ cp $7
+ jr nz, .asm_22159
+ ld a, [$c001]
+ cp $14
+ jr nc, .asm_22152
+ ret
+.asm_22152
+ ld a, [hl]
+ cp $14
+ jr z, .asm_22162
+ jr c, .asm_22162
+.asm_22159
+ ld a, [$c001]
+ cp [hl]
+ jr z, .asm_22162
+ jr c, .asm_22162
+ ret
+.asm_22162
+ xor a
+ push de
+ ld h, d
+ ld l, e
+ add hl, hl
+ ld d, h
+ ld e, l
+ ld hl, $c016
+ add hl, de
+ ld [hli], a
+ ld [hl], a
+ ld hl, $c006
+ add hl, de
+ ld [hli], a
+ ld [hl], a
+ pop de
+ ld hl, $c026
+ add hl, de
+ ld [hl], a
+ ld hl, $c02e
+ add hl, de
+ ld [hl], a
+ ld hl, $c03e
+ add hl, de
+ ld [hl], a
+ ld hl, $c046
+ add hl, de
+ ld [hl], a
+ ld hl, $c04e
+ add hl, de
+ ld [hl], a
+ ld hl, $c056
+ add hl, de
+ ld [hl], a
+ ld hl, $c05e
+ add hl, de
+ ld [hl], a
+ ld hl, $c066
+ add hl, de
+ ld [hl], a
+ ld hl, $c06e
+ add hl, de
+ ld [hl], a
+ ld hl, $c076
+ add hl, de
+ ld [hl], a
+ ld hl, $c07e
+ add hl, de
+ ld [hl], a
+ ld hl, $c086
+ add hl, de
+ ld [hl], a
+ ld hl, $c08e
+ add hl, de
+ ld [hl], a
+ ld hl, $c096
+ add hl, de
+ ld [hl], a
+ ld hl, $c09e
+ add hl, de
+ ld [hl], a
+ ld hl, $c0a6
+ add hl, de
+ ld [hl], a
+ ld hl, $c0ae
+ add hl, de
+ ld [hl], a
+ ld hl, $c036
+ add hl, de
+ ld [hl], a
+ ld a, $1
+ ld hl, $c0be
+ add hl, de
+ ld [hl], a
+ ld hl, $c0b6
+ add hl, de
+ ld [hl], a
+ ld hl, $c0c6
+ add hl, de
+ ld [hl], a
+ ld a, e
+ cp $4
+ jr nz, .asm_221ea
+ ld a, $8
+ ld [$FF00+$10], a
+.asm_221ea
+ ld a, c
+ and a
+ jp z, Func_2224e
+ dec c
+ jp .asm_22126
+
+Func_221f3: ; 221f3 (8:61f3)
+ ld a, $80
+ ld [$FF00+$26], a
+ ld [$FF00+$1a], a
+ xor a
+ ld [$FF00+$25], a
+ ld [$FF00+$1c], a
+ ld a, $8
+ ld [$FF00+$10], a
+ ld [$FF00+$12], a
+ ld [$FF00+$17], a
+ ld [$FF00+$21], a
+ ld a, $40
+ ld [$FF00+$14], a
+ ld [$FF00+$19], a
+ ld [$FF00+$23], a
+ ld a, $77
+ ld [$FF00+$24], a
+ xor a
+ ld [$c000], a
+ ld [$c003], a
+ ld [$c002], a
+ ld [$c0e9], a
+ ld [$c0eb], a
+ ld [$c0e6], a
+ ld [$c0e7], a
+ ld d, $a0
+ ld hl, $c006
+ call FillMusicRAM8
+ ld a, $1
+ ld d, $18
+ ld hl, $c0b6
+ call FillMusicRAM8
+ ld [$c0e8], a
+ ld [$c0ea], a
+ ld a, $ff
+ ld [$c004], a
+ ret
+
+; fills d bytes at hl with a
+FillMusicRAM8: ; 22248 (8:6248)
+ ld b, d
+.loop
+ ld [hli], a
+ dec b
+ jr nz, .loop
+ ret
+
+Func_2224e: ; 2224e (8:624e)
+ ld a, [$c001]
+ ld l, a
+ ld e, a
+ ld h, $0
+ ld d, h
+ add hl, hl
+ add hl, de
+ ld de, SFX_Headers_08
+ add hl, de
+ ld e, l
+ ld d, h
+ ld hl, $c006
+ ld a, [de] ; get channel number
+ ld b, a
+ rlca
+ rlca
+ and $3
+ ld c, a
+ ld a, b
+ and $f
+ ld b, c
+ inc b
+ inc de
+ ld c, $0
+.asm_22270
+ cp c
+ jr z, .asm_22278
+ inc c
+ inc hl
+ inc hl
+ jr .asm_22270
+.asm_22278
+ push hl
+ push bc
+ push af
+ ld b, $0
+ ld c, a
+ ld hl, $c026
+ add hl, bc
+ ld a, [$c001]
+ ld [hl], a
+ pop af
+ cp $3
+ jr c, .asm_22291
+ ld hl, $c02e
+ add hl, bc
+ set 2, [hl]
+.asm_22291
+ pop bc
+ pop hl
+ ld a, [de] ; get channel pointer
+ ld [hli], a
+ inc de
+ ld a, [de]
+ ld [hli], a
+ inc de
+ inc c
+ dec b
+ ld a, b
+ and a
+ ld a, [de]
+ inc de
+ jr nz, .asm_22270
+ ld a, [$c001]
+ cp $14
+ jr nc, .asm_222aa
+ jr .asm_222d4
+.asm_222aa
+ ld a, [$c001]
+ cp $86
+ jr z, .asm_222d4
+ jr c, .asm_222b5
+ jr .asm_222d4
+.asm_222b5
+ ld hl, $c02a
+ ld [hli], a
+ ld [hli], a
+ ld [hli], a
+ ld [hl], a
+ ld hl, $c012 ; sfx noise channel pointer
+ ld de, Noise8_endchannel
+ ld [hl], e
+ inc hl
+ ld [hl], d ; overwrite pointer to point to endchannel
+ ld a, [$c005]
+ and a
+ jr nz, .asm_222d4
+ ld a, [$FF00+$24]
+ ld [$c005], a
+ ld a, $77
+ ld [$FF00+$24], a
+.asm_222d4
+ ret
+
+Noise8_endchannel: ; 222d5 (8:62d5)
+ endchannel
+
+Unknown_222d6: ; 222d6 (8:62d6)
+ db $10, $15, $1A, $1F ; channels 0-3
+ db $10, $15, $1A, $1F ; channels 4-7
+
+Unknown_222de: ; 222de (8:62de)
+ db $EE, $DD, $BB, $77 ; channels 0-3
+ db $EE, $DD, $BB, $77 ; channels 4-7
+
+Unknown_222e6: ; 222e6 (8:62e6)
+ db $11, $22, $44, $88 ; channels 0-3
+ db $11, $22, $44, $88 ; channels 4-7
+
+Unknown_222ee: ; 222ee (8:62ee)
+ dw $F82C
+ dw $F89D
+ dw $F907
+ dw $F96B
+ dw $F9CA
+ dw $FA23
+ dw $FA77
+ dw $FAC7
+ dw $FB12
+ dw $FB58
+ dw $FB9B
+ dw $FBDA
+
+
diff --git a/audio/engine_3.asm b/audio/engine_3.asm
new file mode 100644
index 00000000..1f285ee6
--- /dev/null
+++ b/audio/engine_3.asm
@@ -0,0 +1,1682 @@
+; The third of three duplicated sound engines.
+
+Func_7d177: ; 7d177 (1f:5177)
+ ld c, CH0
+.loop
+ ld b, $0
+ ld hl, $c026
+ add hl, bc
+ ld a, [hl]
+ and a
+ jr z, .nextChannel
+ ld a, c
+ cp CH4
+ jr nc, .applyAffects ; if sfx channel
+ ld a, [$c002]
+ and a
+ jr z, .applyAffects
+ bit 7, a
+ jr nz, .nextChannel
+ set 7, a
+ ld [$c002], a
+ xor a
+ ld [$FF00+$25], a
+ ld [$FF00+$1a], a
+ ld a, $80
+ ld [$FF00+$1a], a
+ jr .nextChannel
+.applyAffects
+ call Music1f_Music2_ApplyMusicAffects
+.nextChannel
+ ld a, c
+ inc c ; inc channel number
+ cp CH7
+ jr nz, .loop
+ ret
+
+; this routine checks flags for music effects currently applied
+; to the channel and calls certain functions based on flags.
+; known flags for $c02e:
+; 1: call has been used
+; 3: a toggle used only by this routine for vibrato
+; 4: pitchbend flag
+; 6: dutycycle flag
+Music1f_Music2_ApplyMusicAffects: ; 7d1ac (1f:51ac)
+ ld b, $0
+ ld hl, $c0b6 ; delay until next note
+ add hl, bc
+ ld a, [hl]
+ cp $1 ; if delay is 1, play next note
+ jp z, Music1f_Music2_PlayNextNote
+ dec a ; otherwise, decrease the delay timer
+ ld [hl], a
+ ld a, c
+ cp CH4
+ jr nc, .startChecks ; if a sfx channel
+ ld hl, $c02a
+ add hl, bc
+ ld a, [hl]
+ and a
+ jr z, .startChecks
+ ret
+.startChecks
+ ld hl, $c02e
+ add hl, bc
+ bit 6, [hl] ; dutycycle
+ jr z, .checkForExecuteMusic
+ call Music1f_ApplyDutyCycle
+.checkForExecuteMusic
+ ld b, $0
+ ld hl, $c036
+ add hl, bc
+ bit 0, [hl]
+ jr nz, .checkForPitchBend
+ ld hl, $c02e
+ add hl, bc
+ bit 2, [hl]
+ jr nz, .disablePitchBendVibrato
+.checkForPitchBend
+ ld hl, $c02e
+ add hl, bc
+ bit 4, [hl] ; pitchbend
+ jr z, .checkVibratoDelay
+ jp Music1f_ApplyPitchBend
+.checkVibratoDelay
+ ld hl, $c04e ; vibrato delay
+ add hl, bc
+ ld a, [hl]
+ and a ; check if delay is over
+ jr z, .checkForVibrato
+ dec [hl] ; otherwise, dec delay
+.disablePitchBendVibrato
+ ret
+.checkForVibrato
+ ld hl, $c056 ; vibrato rate
+ add hl, bc
+ ld a, [hl]
+ and a
+ jr nz, .vibrato
+ ret ; no vibrato
+.vibrato
+ ld d, a
+ ld hl, $c05e
+ add hl, bc
+ ld a, [hl]
+ and $f
+ and a
+ jr z, .vibratoAlreadyDone
+ dec [hl] ; apply vibrato pitch change
+ ret
+.vibratoAlreadyDone
+ ld a, [hl]
+ swap [hl]
+ or [hl]
+ ld [hl], a ; reset the vibrato value and start again
+ ld hl, $c066
+ add hl, bc
+ ld e, [hl] ; get note pitch
+ ld hl, $c02e
+ add hl, bc
+ bit 3, [hl] ; this is the only code that sets/resets bit three so
+ jr z, .unset ; it continuously alternates which path it takes
+ res 3, [hl]
+ ld a, d
+ and $f
+ ld d, a
+ ld a, e
+ sub d
+ jr nc, .noCarry
+ ld a, $0
+.noCarry
+ jr .done
+.unset
+ set 3, [hl]
+ ld a, d
+ and $f0
+ swap a
+ add e
+ jr nc, .done
+ ld a, $ff
+.done
+ ld d, a
+ ld b, $3
+ call Func_7d8ac
+ ld [hl], d
+ ret
+
+; this routine executes all music commands that take up no time,
+; like tempo changes, duty changes etc. and doesn't return
+; until the first note is reached
+Music1f_Music2_PlayNextNote: ; 7d244 (1f:5244)
+ ld hl, $c06e
+ add hl, bc
+ ld a, [hl]
+ ld hl, $c04e
+ add hl, bc
+ ld [hl], a
+ ld hl, $c02e
+ add hl, bc
+ res 4, [hl]
+ res 5, [hl]
+ call Music1f_endchannel
+ ret
+
+Music1f_endchannel: ; 7d25a (1f:525a)
+ call Music1f_GetNextMusicByte
+ ld d, a
+ cp $ff ; is this command an endchannel?
+ jp nz, Music1f_callchannel ; no
+ ld b, $0 ; yes
+ ld hl, $c02e
+ add hl, bc
+ bit 1, [hl]
+ jr nz, .returnFromCall
+ ld a, c
+ cp CH3
+ jr nc, .noiseOrSfxChannel
+ jr .asm_7d2b3
+.noiseOrSfxChannel
+ res 2, [hl]
+ ld hl, $c036
+ add hl, bc
+ res 0, [hl]
+ cp CH6
+ jr nz, .notSfxChannel3
+ ld a, $0
+ ld [$FF00+$1a], a
+ ld a, $80
+ ld [$FF00+$1a], a
+.notSfxChannel3
+ jr nz, .asm_7d296
+ ld a, [$c003]
+ and a
+ jr z, .asm_7d296
+ xor a
+ ld [$c003], a
+ jr .asm_7d2b3
+.asm_7d296
+ jr .asm_7d2bc
+.returnFromCall
+ res 1, [hl]
+ ld d, $0
+ ld a, c
+ add a
+ ld e, a
+ ld hl, $c006
+ add hl, de
+ push hl ; store current channel address
+ ld hl, $c016
+ add hl, de
+ ld e, l
+ ld d, h
+ pop hl
+ ld a, [de]
+ ld [hli], a
+ inc de
+ ld a, [de]
+ ld [hl], a ; loads channel address to return to
+ jp Music1f_endchannel
+.asm_7d2b3
+ ld hl, Unknown_7db93
+ add hl, bc
+ ld a, [$FF00+$25]
+ and [hl]
+ ld [$FF00+$25], a
+.asm_7d2bc
+ ld a, [$c02a]
+ cp $14
+ jr nc, .asm_7d2c5
+ jr .asm_7d2e2
+.asm_7d2c5
+ ld a, [$c02a]
+ cp $86
+ jr z, .asm_7d2e2
+ jr c, .asm_7d2d0
+ jr .asm_7d2e2
+.asm_7d2d0
+ ld a, c
+ cp CH4
+ jr z, .asm_7d2d9
+ call Func_7d73b
+ ret c
+.asm_7d2d9
+ ld a, [$c005]
+ ld [$FF00+$24], a
+ xor a
+ ld [$c005], a
+.asm_7d2e2
+ ld hl, $c026
+ add hl, bc
+ ld [hl], b
+ ret
+
+Music1f_callchannel: ; 7d2e8 (1f:52e8)
+ cp $fd ; is this command a callchannel?
+ jp nz, Music1f_loopchannel ; no
+ call Music1f_GetNextMusicByte ; yes
+ push af
+ call Music1f_GetNextMusicByte
+ ld d, a
+ pop af
+ ld e, a
+ push de ; store pointer
+ ld d, $0
+ ld a, c
+ add a
+ ld e, a
+ ld hl, $c006
+ add hl, de
+ push hl
+ ld hl, $c016
+ add hl, de
+ ld e, l
+ ld d, h
+ pop hl
+ ld a, [hli]
+ ld [de], a
+ inc de
+ ld a, [hld]
+ ld [de], a ; copy current channel address
+ pop de
+ ld [hl], e
+ inc hl
+ ld [hl], d ; overwrite current address with pointer
+ ld b, $0
+ ld hl, $c02e
+ add hl, bc
+ set 1, [hl] ; set the call flag
+ jp Music1f_endchannel
+
+Music1f_loopchannel: ; 7d31d (1f:531d)
+ cp $fe ; is this command a loopchannel?
+ jp nz, Music1f_notetype ; no
+ call Music1f_GetNextMusicByte ; yes
+ ld e, a
+ and a
+ jr z, .infiniteLoop
+ ld b, $0
+ ld hl, $c0be
+ add hl, bc
+ ld a, [hl]
+ cp e
+ jr nz, .loopAgain
+ ld a, $1 ; if no more loops to make
+ ld [hl], a
+ call Music1f_GetNextMusicByte ; skip pointer
+ call Music1f_GetNextMusicByte
+ jp Music1f_endchannel
+.loopAgain ; inc loop count
+ inc a
+ ld [hl], a
+ ; fall through
+.infiniteLoop ; overwrite current address with pointer
+ call Music1f_GetNextMusicByte
+ push af
+ call Music1f_GetNextMusicByte
+ ld b, a
+ ld d, $0
+ ld a, c
+ add a
+ ld e, a
+ ld hl, $c006
+ add hl, de
+ pop af
+ ld [hli], a
+ ld [hl], b
+ jp Music1f_endchannel
+
+Music1f_notetype: ; 7d358 (1f:5358)
+ and $f0
+ cp $d0 ; is this command a notetype?
+ jp nz, Music1f_togglecall ; no
+ ld a, d ; yes
+ and $f
+ ld b, $0
+ ld hl, $c0c6
+ add hl, bc
+ ld [hl], a ; store low nibble as speed
+ ld a, c
+ cp CH3
+ jr z, .noiseChannel ; noise channel has 0 params
+ call Music1f_GetNextMusicByte
+ ld d, a
+ ld a, c
+ cp CH2
+ jr z, .musicChannel3
+ cp CH6
+ jr nz, .notChannel3
+ ld hl, $c0e7
+ jr .sfxChannel3
+.musicChannel3
+ ld hl, $c0e6
+.sfxChannel3
+ ld a, d
+ and $f
+ ld [hl], a ; store low nibble of param as duty
+ ld a, d
+ and $30
+ sla a
+ ld d, a
+ ; fall through
+
+ ; if channel 3, store high nibble as volume
+ ; else, store volume (high nibble) and fade (low nibble)
+.notChannel3
+ ld b, $0
+ ld hl, $c0de
+ add hl, bc
+ ld [hl], d
+.noiseChannel
+ jp Music1f_endchannel
+
+Music1f_togglecall: ; 7d397 (1f:5397)
+ ld a, d
+ cp $e8 ; is this command an togglecall?
+ jr nz, Music1f_vibrato ; no
+ ld b, $0 ; yes
+ ld hl, $c02e
+ add hl, bc
+ ld a, [hl]
+ xor $1
+ ld [hl], a ; flip bit 0 of $c02e (toggle returning from call)
+ jp Music1f_endchannel
+
+Music1f_vibrato: ; 7d3a9 (1f:53a9)
+ cp $ea ; is this command a vibrato?
+ jr nz, Music1f_pitchbend ; no
+ call Music1f_GetNextMusicByte ; yes
+ ld b, $0
+ ld hl, $c04e
+ add hl, bc
+ ld [hl], a ; store delay
+ ld hl, $c06e
+ add hl, bc
+ ld [hl], a ; store delay
+ call Music1f_GetNextMusicByte
+ ld d, a
+ and $f0
+ swap a
+ ld b, $0
+ ld hl, $c056
+ add hl, bc
+ srl a
+ ld e, a
+ adc b
+ swap a
+ or e
+ ld [hl], a ; store rate as both high and low nibbles
+ ld a, d
+ and $f
+ ld d, a
+ ld hl, $c05e
+ add hl, bc
+ swap a
+ or d
+ ld [hl], a ; store depth as both high and low nibbles
+ jp Music1f_endchannel
+
+Music1f_pitchbend: ; 7d3e1 (1f:53e1)
+ cp $eb ; is this command a pitchbend?
+ jr nz, Music1f_duty ; no
+ call Music1f_GetNextMusicByte ; yes
+ ld b, $0
+ ld hl, $c076
+ add hl, bc
+ ld [hl], a ; store first param
+ call Music1f_GetNextMusicByte
+ ld d, a
+ and $f0
+ swap a
+ ld b, a
+ ld a, d
+ and $f
+ call Func_7d8cc
+ ld b, $0
+ ld hl, $c0a6
+ add hl, bc
+ ld [hl], d ; store unknown part of second param
+ ld hl, $c0ae
+ add hl, bc
+ ld [hl], e ; store unknown part of second param
+ ld b, $0
+ ld hl, $c02e
+ add hl, bc
+ set 4, [hl] ; set pitchbend flag
+ call Music1f_GetNextMusicByte
+ ld d, a
+ jp Music1f_notelength
+
+Music1f_duty: ; 7d419 (1f:5419)
+ cp $ec ; is this command a duty?
+ jr nz, Music1f_tempo ; no
+ call Music1f_GetNextMusicByte ; yes
+ rrca
+ rrca
+ and $c0
+ ld b, $0
+ ld hl, $c03e
+ add hl, bc
+ ld [hl], a ; store duty
+ jp Music1f_endchannel
+
+Music1f_tempo: ; 7d42e (1f:542e)
+ cp $ed ; is this command a tempo?
+ jr nz, Music1f_unknownmusic0xee ; no
+ ld a, c ; yes
+ cp CH4
+ jr nc, .sfxChannel
+ call Music1f_GetNextMusicByte
+ ld [$c0e8], a ; store first param
+ call Music1f_GetNextMusicByte
+ ld [$c0e9], a ; store second param
+ xor a
+ ld [$c0ce], a ; clear RAM
+ ld [$c0cf], a
+ ld [$c0d0], a
+ ld [$c0d1], a
+ jr .musicChannelDone
+.sfxChannel
+ call Music1f_GetNextMusicByte
+ ld [$c0ea], a ; store first param
+ call Music1f_GetNextMusicByte
+ ld [$c0eb], a ; store second param
+ xor a
+ ld [$c0d2], a ; clear RAM
+ ld [$c0d3], a
+ ld [$c0d4], a
+ ld [$c0d5], a
+.musicChannelDone
+ jp Music1f_endchannel
+
+Music1f_unknownmusic0xee: ; 7d46e (1f:546e)
+ cp $ee ; is this command an unknownmusic0xee?
+ jr nz, Music1f_unknownmusic0xef ; no
+ call Music1f_GetNextMusicByte ; yes
+ ld [$c004], a ; store first param
+ jp Music1f_endchannel
+
+; this appears to never be used
+Music1f_unknownmusic0xef: ; 7d47b (1f:547b)
+ cp $ef ; is this command an unknownmusic0xef?
+ jr nz, Music1f_dutycycle ; no
+ call Music1f_GetNextMusicByte ; yes
+ push bc
+ call Func_7d8ea
+ pop bc
+ ld a, [$c003]
+ and a
+ jr nz, .skip
+ ld a, [$c02d]
+ ld [$c003], a
+ xor a
+ ld [$c02d], a
+.skip
+ jp Music1f_endchannel
+
+Music1f_dutycycle: ; 7d49a (1f:549a)
+ cp $fc ; is this command a dutycycle?
+ jr nz, Music1f_stereopanning ; no
+ call Music1f_GetNextMusicByte ; yes
+ ld b, $0
+ ld hl, $c046
+ add hl, bc
+ ld [hl], a ; store full cycle
+ and $c0
+ ld hl, $c03e
+ add hl, bc
+ ld [hl], a ; store first duty
+ ld hl, $c02e
+ add hl, bc
+ set 6, [hl] ; set duty flag
+ jp Music1f_endchannel
+
+Music1f_stereopanning: ; 7d4b8 (1f:54b8)
+ cp $f0 ; is this command a stereopanning?
+ jr nz, Music1f_executemusic ; no
+ call Music1f_GetNextMusicByte ; yes
+ ld [$FF00+$24], a ; store stereopanning
+ jp Music1f_endchannel
+
+Music1f_executemusic: ; 7d4c4 (1f:54c4)
+ cp $f8 ; is this command an executemusic?
+ jr nz, Music1f_octave ; no
+ ld b, $0 ; yes
+ ld hl, $c036
+ add hl, bc
+ set 0, [hl]
+ jp Music1f_endchannel
+
+Music1f_octave: ; 7d4d3 (1f:54d3)
+ and $f0
+ cp $e0 ; is this command an octave?
+ jr nz, Music1f_unknownsfx0x20 ; no
+ ld hl, $c0d6 ; yes
+ ld b, $0
+ add hl, bc
+ ld a, d
+ and $f
+ ld [hl], a ; store low nibble as octave
+ jp Music1f_endchannel
+
+Music1f_unknownsfx0x20: ; 7d4e6 (1f:54e6)
+ cp $20 ; is this command an unknownsfx0x20?
+ jr nz, Music1f_unknownsfx0x10 ; no
+ ld a, c
+ cp CH3 ; is this a noise or sfx channel?
+ jr c, Music1f_unknownsfx0x10 ; no
+ ld b, $0
+ ld hl, $c036
+ add hl, bc
+ bit 0, [hl]
+ jr nz, Music1f_unknownsfx0x10 ; no
+ call Music1f_notelength ; yes
+ ld d, a
+ ld b, $0
+ ld hl, $c03e
+ add hl, bc
+ ld a, [hl]
+ or d
+ ld d, a
+ ld b, $1
+ call Func_7d8ac
+ ld [hl], d
+ call Music1f_GetNextMusicByte
+ ld d, a
+ ld b, $2
+ call Func_7d8ac
+ ld [hl], d
+ call Music1f_GetNextMusicByte
+ ld e, a
+ ld a, c
+ cp CH7
+ ld a, $0
+ jr z, .sfxNoiseChannel ; only two params for noise channel
+ push de
+ call Music1f_GetNextMusicByte
+ pop de
+.sfxNoiseChannel
+ ld d, a
+ push de
+ call Func_7d69d
+ call Func_7d66c
+ pop de
+ call Func_7d6bf
+ ret
+
+Music1f_unknownsfx0x10 ; 7d533 (1f:5533)
+ ld a, c
+ cp CH4
+ jr c, Music1f_note ; if not a sfx
+ ld a, d
+ cp $10 ; is this command an unknownsfx0x10?
+ jr nz, Music1f_note ; no
+ ld b, $0
+ ld hl, $c036
+ add hl, bc
+ bit 0, [hl]
+ jr nz, Music1f_note ; no
+ call Music1f_GetNextMusicByte ; yes
+ ld [$FF00+$10], a
+ jp Music1f_endchannel
+
+Music1f_note: ; 7d54f (1f:554f)
+ ld a, c
+ cp CH3
+ jr nz, Music1f_notelength ; if not noise channel
+ ld a, d
+ and $f0
+ cp $b0 ; is this command a dnote?
+ jr z, Music1f_dnote ; yes
+ jr nc, Music1f_notelength ; no
+ swap a
+ ld b, a
+ ld a, d
+ and $f
+ ld d, a
+ ld a, b
+ push de
+ push bc
+ jr asm_7d571
+
+Music1f_dnote: ; 7d569 (1f:5569)
+ ld a, d
+ and $f
+ push af
+ push bc
+ call Music1f_GetNextMusicByte ; get dnote instrument
+asm_7d571
+ ld d, a
+ ld a, [$c003]
+ and a
+ jr nz, .asm_7d57c
+ ld a, d
+ call Func_7d8ea
+.asm_7d57c
+ pop bc
+ pop de
+
+Music1f_notelength: ; 7d57e (1f:557e)
+ ld a, d
+ push af
+ and $f
+ inc a
+ ld b, $0
+ ld e, a ; store note length (in 16ths)
+ ld d, b
+ ld hl, $c0c6
+ add hl, bc
+ ld a, [hl]
+ ld l, b
+ call Func_7d8bb
+ ld a, c
+ cp CH4
+ jr nc, .sfxChannel
+ ld a, [$c0e8]
+ ld d, a
+ ld a, [$c0e9]
+ ld e, a
+ jr .skip
+.sfxChannel
+ ld d, $1
+ ld e, $0
+ cp CH7
+ jr z, .skip ; if noise channel
+ call Func_7d707
+ ld a, [$c0ea]
+ ld d, a
+ ld a, [$c0eb]
+ ld e, a
+.skip
+ ld a, l
+ ld b, $0
+ ld hl, $c0ce
+ add hl, bc
+ ld l, [hl]
+ call Func_7d8bb
+ ld e, l
+ ld d, h
+ ld hl, $c0ce
+ add hl, bc
+ ld [hl], e
+ ld a, d
+ ld hl, $c0b6
+ add hl, bc
+ ld [hl], a
+ ld hl, $c036
+ add hl, bc
+ bit 0, [hl]
+ jr nz, Music1f_notepitch
+ ld hl, $c02e
+ add hl, bc
+ bit 2, [hl]
+ jr z, Music1f_notepitch
+ pop hl
+ ret
+
+Music1f_notepitch: ; 7d5dc (1f:55dc)
+ pop af
+ and $f0
+ cp $c0 ; compare to rest
+ jr nz, .notRest
+ ld a, c
+ cp CH4
+ jr nc, .sfxChannel
+ ld hl, $c02a
+ add hl, bc
+ ld a, [hl]
+ and a
+ jr nz, .quit
+ ; fall through
+.sfxChannel
+ ld a, c
+ cp CH2
+ jr z, .musicChannel3
+ cp CH6
+ jr nz, .notSfxChannel3
+.musicChannel3
+ ld b, $0
+ ld hl, Unknown_7db93
+ add hl, bc
+ ld a, [$FF00+$25]
+ and [hl]
+ ld [$FF00+$25], a
+ jr .quit
+.notSfxChannel3
+ ld b, $2
+ call Func_7d8ac
+ ld a, $8
+ ld [hli], a
+ inc hl
+ ld a, $80
+ ld [hl], a
+.quit
+ ret
+.notRest
+ swap a
+ ld b, $0
+ ld hl, $c0d6
+ add hl, bc
+ ld b, [hl]
+ call Func_7d8cc
+ ld b, $0
+ ld hl, $c02e
+ add hl, bc
+ bit 4, [hl]
+ jr z, .asm_7d62c
+ call Func_7d803
+.asm_7d62c
+ push de
+ ld a, c
+ cp CH4
+ jr nc, .skip ; if sfx Channel
+ ld hl, $c02a
+ ld d, $0
+ ld e, a
+ add hl, de
+ ld a, [hl]
+ and a
+ jr nz, .done
+ jr .skip
+.done
+ pop de
+ ret
+.skip
+ ld b, $0
+ ld hl, $c0de
+ add hl, bc
+ ld d, [hl]
+ ld b, $2
+ call Func_7d8ac
+ ld [hl], d
+ call Func_7d69d
+ call Func_7d66c
+ pop de
+ ld b, $0
+ ld hl, $c02e
+ add hl, bc
+ bit 0, [hl]
+ jr z, .asm_7d663
+ inc e
+ jr nc, .asm_7d663
+ inc d
+.asm_7d663
+ ld hl, $c066
+ add hl, bc
+ ld [hl], e
+ call Func_7d6bf
+ ret
+
+Func_7d66c: ; 7d66c (1f:566c)
+ ld b, $0
+ ld hl, Unknown_7db9b
+ add hl, bc
+ ld a, [$FF00+$25]
+ or [hl]
+ ld d, a
+ ld a, c
+ cp CH7
+ jr z, .sfxNoiseChannel
+ cp CH4
+ jr nc, .skip ; if sfx channel
+ ld hl, $c02a
+ add hl, bc
+ ld a, [hl]
+ and a
+ jr nz, .skip
+.sfxNoiseChannel
+ ld a, [$c004]
+ ld hl, Unknown_7db9b
+ add hl, bc
+ and [hl]
+ ld d, a
+ ld a, [$FF00+$25]
+ ld hl, Unknown_7db93
+ add hl, bc
+ and [hl]
+ or d
+ ld d, a
+.skip
+ ld a, d
+ ld [$FF00+$25], a
+ ret
+
+Func_7d69d: ; 7d69d (1f:569d)
+ ld b, $0
+ ld hl, $c0b6
+ add hl, bc
+ ld d, [hl]
+ ld a, c
+ cp CH2
+ jr z, .channel3 ; if music channel 3
+ cp CH6
+ jr z, .channel3 ; if sfx channel 3
+ ld a, d
+ and $3f
+ ld d, a
+ ld hl, $c03e
+ add hl, bc
+ ld a, [hl]
+ or d
+ ld d, a
+.channel3
+ ld b, $1
+ call Func_7d8ac
+ ld [hl], d
+ ret
+
+Func_7d6bf: ; 7d6bf (1f:56bf)
+ ld a, c
+ cp CH2
+ jr z, .channel3
+ cp CH6
+ jr nz, .notSfxChannel3
+ ; fall through
+.channel3
+ push de
+ ld de, $c0e6
+ cp CH2
+ jr z, .musicChannel3
+ ld de, $c0e7
+.musicChannel3
+ ld a, [de]
+ add a
+ ld d, $0
+ ld e, a
+ ld hl, Music1f_Channel3DutyPointers
+ add hl, de
+ ld e, [hl]
+ inc hl
+ ld d, [hl]
+ ld hl, $ff30
+ ld b, $f
+ ld a, $0
+ ld [$FF00+$1a], a
+.loop
+ ld a, [de]
+ inc de
+ ld [hli], a
+ ld a, b
+ dec b
+ and a
+ jr nz, .loop
+ ld a, $80
+ ld [$FF00+$1a], a
+ pop de
+.notSfxChannel3
+ ld a, d
+ or $80
+ and $c7
+ ld d, a
+ ld b, $3
+ call Func_7d8ac
+ ld [hl], e
+ inc hl
+ ld [hl], d
+ call Func_7d729
+ ret
+
+Func_7d707: ; 7d707 (1f:5707)
+ call Func_7d759
+ jr nc, .asm_7d71f
+ ld d, $0
+ ld a, [$c0f2]
+ add $80
+ jr nc, .asm_7d716
+ inc d
+.asm_7d716
+ ld [$c0eb], a
+ ld a, d
+ ld [$c0ea], a
+ jr .asm_7d728
+.asm_7d71f
+ xor a
+ ld [$c0eb], a
+ ld a, $1
+ ld [$c0ea], a
+.asm_7d728
+ ret
+
+Func_7d729: ; 7d729 (1f:5729)
+ call Func_7d759
+ jr nc, .asm_7d73a
+ ld a, [$c0f1]
+ add e
+ jr nc, .asm_7d735
+ inc d
+.asm_7d735
+ dec hl
+ ld e, a
+ ld [hl], e
+ inc hl
+ ld [hl], d
+.asm_7d73a
+ ret
+
+Func_7d73b: ; 7d73b (1f:573b)
+ call Func_7d759
+ jr nc, .asm_7d756
+ ld hl, $c006
+ ld e, c
+ ld d, $0
+ sla e
+ rl d
+ add hl, de
+ ld a, [hl]
+ sub $1
+ ld [hl], a
+ inc hl
+ ld a, [hl]
+ sbc $0
+ ld [hl], a
+ scf
+ ret
+.asm_7d756
+ scf
+ ccf
+ ret
+
+Func_7d759: ; 7d759 (1f:5759)
+ ld a, [$c02a]
+ cp $14
+ jr nc, .asm_7d762
+ jr .asm_7d768
+.asm_7d762
+ cp $86
+ jr z, .asm_7d768
+ jr c, .asm_7d76b
+.asm_7d768
+ scf
+ ccf
+ ret
+.asm_7d76b
+ scf
+ ret
+
+Music1f_ApplyPitchBend: ; 7d76d (1f:576d)
+ ld hl, $c02e
+ add hl, bc
+ bit 5, [hl]
+ jp nz, .asm_7d7b4
+ ld hl, $c09e
+ add hl, bc
+ ld e, [hl]
+ ld hl, $c096
+ add hl, bc
+ ld d, [hl]
+ ld hl, $c07e
+ add hl, bc
+ ld l, [hl]
+ ld h, b
+ add hl, de
+ ld d, h
+ ld e, l
+ ld hl, $c08e
+ add hl, bc
+ push hl
+ ld hl, $c086
+ add hl, bc
+ ld a, [hl]
+ pop hl
+ add [hl]
+ ld [hl], a
+ ld a, $0
+ adc e
+ ld e, a
+ ld a, $0
+ adc d
+ ld d, a
+ ld hl, $c0a6
+ add hl, bc
+ ld a, [hl]
+ cp d
+ jp c, .asm_7d7fa
+ jr nz, .asm_7d7e7
+ ld hl, $c0ae
+ add hl, bc
+ ld a, [hl]
+ cp e
+ jp c, .asm_7d7fa
+ jr .asm_7d7e7
+.asm_7d7b4
+ ld hl, $c09e
+ add hl, bc
+ ld a, [hl]
+ ld hl, $c096
+ add hl, bc
+ ld d, [hl]
+ ld hl, $c07e
+ add hl, bc
+ ld e, [hl]
+ sub e
+ ld e, a
+ ld a, d
+ sbc b
+ ld d, a
+ ld hl, $c086
+ add hl, bc
+ ld a, [hl]
+ add a
+ ld [hl], a
+ ld a, e
+ sbc b
+ ld e, a
+ ld a, d
+ sbc b
+ ld d, a
+ ld hl, $c0a6
+ add hl, bc
+ ld a, d
+ cp [hl]
+ jr c, .asm_7d7fa
+ jr nz, .asm_7d7e7
+ ld hl, $c0ae
+ add hl, bc
+ ld a, e
+ cp [hl]
+ jr c, .asm_7d7fa
+.asm_7d7e7
+ ld hl, $c09e
+ add hl, bc
+ ld [hl], e
+ ld hl, $c096
+ add hl, bc
+ ld [hl], d
+ ld b, $3
+ call Func_7d8ac
+ ld a, e
+ ld [hli], a
+ ld [hl], d
+ ret
+.asm_7d7fa
+ ld hl, $c02e
+ add hl, bc
+ res 4, [hl]
+ res 5, [hl]
+ ret
+
+Func_7d803: ; 7d803 (1f:5803)
+ ld hl, $c096
+ add hl, bc
+ ld [hl], d
+ ld hl, $c09e
+ add hl, bc
+ ld [hl], e
+ ld hl, $c0b6
+ add hl, bc
+ ld a, [hl]
+ ld hl, $c076
+ add hl, bc
+ sub [hl]
+ jr nc, .asm_7d81b
+ ld a, $1
+.asm_7d81b
+ ld [hl], a
+ ld hl, $c0ae
+ add hl, bc
+ ld a, e
+ sub [hl]
+ ld e, a
+ ld a, d
+ sbc b
+ ld hl, $c0a6
+ add hl, bc
+ sub [hl]
+ jr c, .asm_7d837
+ ld d, a
+ ld b, $0
+ ld hl, $c02e
+ add hl, bc
+ set 5, [hl]
+ jr .asm_7d85a
+.asm_7d837
+ ld hl, $c096
+ add hl, bc
+ ld d, [hl]
+ ld hl, $c09e
+ add hl, bc
+ ld e, [hl]
+ ld hl, $c0ae
+ add hl, bc
+ ld a, [hl]
+ sub e
+ ld e, a
+ ld a, d
+ sbc b
+ ld d, a
+ ld hl, $c0a6
+ add hl, bc
+ ld a, [hl]
+ sub d
+ ld d, a
+ ld b, $0
+ ld hl, $c02e
+ add hl, bc
+ res 5, [hl]
+.asm_7d85a
+ ld hl, $c076
+ add hl, bc
+.asm_7d85e
+ inc b
+ ld a, e
+ sub [hl]
+ ld e, a
+ jr nc, .asm_7d85e
+ ld a, d
+ and a
+ jr z, .asm_7d86c
+ dec a
+ ld d, a
+ jr .asm_7d85e
+.asm_7d86c
+ ld a, e
+ add [hl]
+ ld d, b
+ ld b, $0
+ ld hl, $c07e
+ add hl, bc
+ ld [hl], d
+ ld hl, $c086
+ add hl, bc
+ ld [hl], a
+ ld hl, $c08e
+ add hl, bc
+ ld [hl], a
+ ret
+
+Music1f_ApplyDutyCycle: ; 7d881 (1f:5881)
+ ld b, $0
+ ld hl, $c046
+ add hl, bc
+ ld a, [hl]
+ rlca
+ rlca
+ ld [hl], a
+ and $c0
+ ld d, a
+ ld b, $1
+ call Func_7d8ac
+ ld a, [hl]
+ and $3f
+ or d
+ ld [hl], a
+ ret
+
+Music1f_GetNextMusicByte: ; 7d899 (1f:5899)
+ ld d, $0
+ ld a, c
+ add a
+ ld e, a
+ ld hl, $c006
+ add hl, de
+ ld a, [hli]
+ ld e, a
+ ld a, [hld]
+ ld d, a
+ ld a, [de] ; get next music command
+ inc de
+ ld [hl], e ; store address of next command
+ inc hl
+ ld [hl], d
+ ret
+
+Func_7d8ac: ; 7d8ac (1f:58ac)
+ ld a, c
+ ld hl, Unknown_7db8b
+ add l
+ jr nc, .noCarry
+ inc h
+.noCarry
+ ld l, a
+ ld a, [hl]
+ add b
+ ld l, a
+ ld h, $ff
+ ret
+
+Func_7d8bb: ; 7d8bb (1f:58bb)
+ ld h, $0
+.loop
+ srl a
+ jr nc, .noCarry
+ add hl, de
+.noCarry
+ sla e
+ rl d
+ and a
+ jr z, .done
+ jr .loop
+.done
+ ret
+
+Func_7d8cc: ; 7d8cc (1f:58cc)
+ ld h, $0
+ ld l, a
+ add hl, hl
+ ld d, h
+ ld e, l
+ ld hl, Unknown_7dba3
+ add hl, de
+ ld e, [hl]
+ inc hl
+ ld d, [hl]
+ ld a, b
+.loop
+ cp $7
+ jr z, .done
+ sra d
+ rr e
+ inc a
+ jr .loop
+.done
+ ld a, $8
+ add d
+ ld d, a
+ ret
+
+Func_7d8ea: ; 7d8ea (1f:58ea)
+ ld [$c001], a
+ cp $ff
+ jp z, Func_7daa8
+ cp $c2
+ jp z, Func_7d9c2
+ jp c, Func_7d9c2
+ cp $fe
+ jr z, .asm_7d901
+ jp nc, Func_7d9c2
+.asm_7d901
+ xor a
+ ld [$c000], a
+ ld [$c003], a
+ ld [$c0e9], a
+ ld [$c0e6], a
+ ld [$c0e7], a
+ ld d, $8
+ ld hl, $c016
+ call FillMusicRAM1f
+ ld hl, $c006
+ call FillMusicRAM1f
+ ld d, $4
+ ld hl, $c026
+ call FillMusicRAM1f
+ ld hl, $c02e
+ call FillMusicRAM1f
+ ld hl, $c03e
+ call FillMusicRAM1f
+ ld hl, $c046
+ call FillMusicRAM1f
+ ld hl, $c04e
+ call FillMusicRAM1f
+ ld hl, $c056
+ call FillMusicRAM1f
+ ld hl, $c05e
+ call FillMusicRAM1f
+ ld hl, $c066
+ call FillMusicRAM1f
+ ld hl, $c06e
+ call FillMusicRAM1f
+ ld hl, $c036
+ call FillMusicRAM1f
+ ld hl, $c076
+ call FillMusicRAM1f
+ ld hl, $c07e
+ call FillMusicRAM1f
+ ld hl, $c086
+ call FillMusicRAM1f
+ ld hl, $c08e
+ call FillMusicRAM1f
+ ld hl, $c096
+ call FillMusicRAM1f
+ ld hl, $c09e
+ call FillMusicRAM1f
+ ld hl, $c0a6
+ call FillMusicRAM1f
+ ld hl, $c0ae
+ call FillMusicRAM1f
+ ld a, $1
+ ld hl, $c0be
+ call FillMusicRAM1f
+ ld hl, $c0b6
+ call FillMusicRAM1f
+ ld hl, $c0c6
+ call FillMusicRAM1f
+ ld [$c0e8], a
+ ld a, $ff
+ ld [$c004], a
+ xor a
+ ld [$FF00+$24], a
+ ld a, $8
+ ld [$FF00+$10], a
+ ld a, $0
+ ld [$FF00+$25], a
+ xor a
+ ld [$FF00+$1a], a
+ ld a, $80
+ ld [$FF00+$1a], a
+ ld a, $77
+ ld [$FF00+$24], a
+ jp Func_7db03
+
+Func_7d9c2: ; 7d9c2 (1f:59c2)
+ ld l, a
+ ld e, a
+ ld h, $0
+ ld d, h
+ add hl, hl
+ add hl, de
+ ld de, SFX_Headers_1f
+ add hl, de
+ ld a, h
+ ld [$c0ec], a
+ ld a, l
+ ld [$c0ed], a
+ ld a, [hl]
+ and $c0
+ rlca
+ rlca
+ ld c, a
+.asm_7d9db
+ ld d, c
+ ld a, c
+ add a
+ add c
+ ld c, a
+ ld b, $0
+ ld a, [$c0ec]
+ ld h, a
+ ld a, [$c0ed]
+ ld l, a
+ add hl, bc
+ ld c, d
+ ld a, [hl]
+ and $f
+ ld e, a
+ ld d, $0
+ ld hl, $c026
+ add hl, de
+ ld a, [hl]
+ and a
+ jr z, .asm_7da17
+ ld a, e
+ cp $7
+ jr nz, .asm_7da0e
+ ld a, [$c001]
+ cp $14
+ jr nc, .asm_7da07
+ ret
+.asm_7da07
+ ld a, [hl]
+ cp $14
+ jr z, .asm_7da17
+ jr c, .asm_7da17
+.asm_7da0e
+ ld a, [$c001]
+ cp [hl]
+ jr z, .asm_7da17
+ jr c, .asm_7da17
+ ret
+.asm_7da17
+ xor a
+ push de
+ ld h, d
+ ld l, e
+ add hl, hl
+ ld d, h
+ ld e, l
+ ld hl, $c016
+ add hl, de
+ ld [hli], a
+ ld [hl], a
+ ld hl, $c006
+ add hl, de
+ ld [hli], a
+ ld [hl], a
+ pop de
+ ld hl, $c026
+ add hl, de
+ ld [hl], a
+ ld hl, $c02e
+ add hl, de
+ ld [hl], a
+ ld hl, $c03e
+ add hl, de
+ ld [hl], a
+ ld hl, $c046
+ add hl, de
+ ld [hl], a
+ ld hl, $c04e
+ add hl, de
+ ld [hl], a
+ ld hl, $c056
+ add hl, de
+ ld [hl], a
+ ld hl, $c05e
+ add hl, de
+ ld [hl], a
+ ld hl, $c066
+ add hl, de
+ ld [hl], a
+ ld hl, $c06e
+ add hl, de
+ ld [hl], a
+ ld hl, $c076
+ add hl, de
+ ld [hl], a
+ ld hl, $c07e
+ add hl, de
+ ld [hl], a
+ ld hl, $c086
+ add hl, de
+ ld [hl], a
+ ld hl, $c08e
+ add hl, de
+ ld [hl], a
+ ld hl, $c096
+ add hl, de
+ ld [hl], a
+ ld hl, $c09e
+ add hl, de
+ ld [hl], a
+ ld hl, $c0a6
+ add hl, de
+ ld [hl], a
+ ld hl, $c0ae
+ add hl, de
+ ld [hl], a
+ ld hl, $c036
+ add hl, de
+ ld [hl], a
+ ld a, $1
+ ld hl, $c0be
+ add hl, de
+ ld [hl], a
+ ld hl, $c0b6
+ add hl, de
+ ld [hl], a
+ ld hl, $c0c6
+ add hl, de
+ ld [hl], a
+ ld a, e
+ cp $4
+ jr nz, .asm_7da9f
+ ld a, $8
+ ld [$FF00+$10], a
+.asm_7da9f
+ ld a, c
+ and a
+ jp z, Func_7db03
+ dec c
+ jp .asm_7d9db
+
+Func_7daa8: ; 7daa8 (1f:5aa8)
+ ld a, $80
+ ld [$FF00+$26], a
+ ld [$FF00+$1a], a
+ xor a
+ ld [$FF00+$25], a
+ ld [$FF00+$1c], a
+ ld a, $8
+ ld [$FF00+$10], a
+ ld [$FF00+$12], a
+ ld [$FF00+$17], a
+ ld [$FF00+$21], a
+ ld a, $40
+ ld [$FF00+$14], a
+ ld [$FF00+$19], a
+ ld [$FF00+$23], a
+ ld a, $77
+ ld [$FF00+$24], a
+ xor a
+ ld [$c000], a
+ ld [$c003], a
+ ld [$c002], a
+ ld [$c0e9], a
+ ld [$c0eb], a
+ ld [$c0e6], a
+ ld [$c0e7], a
+ ld d, $a0
+ ld hl, $c006
+ call FillMusicRAM1f
+ ld a, $1
+ ld d, $18
+ ld hl, $c0b6
+ call FillMusicRAM1f
+ ld [$c0e8], a
+ ld [$c0ea], a
+ ld a, $ff
+ ld [$c004], a
+ ret
+
+; fills d bytes at hl with a
+FillMusicRAM1f: ; 7dafd (1f:5afd)
+ ld b, d
+.loop
+ ld [hli], a
+ dec b
+ jr nz, .loop
+ ret
+
+Func_7db03: ; 7db03 (1f:5b03)
+ ld a, [$c001]
+ ld l, a
+ ld e, a
+ ld h, $0
+ ld d, h
+ add hl, hl
+ add hl, de
+ ld de, SFX_Headers_1f
+ add hl, de
+ ld e, l
+ ld d, h
+ ld hl, $c006
+ ld a, [de] ; get channel number
+ ld b, a
+ rlca
+ rlca
+ and $3
+ ld c, a
+ ld a, b
+ and $f
+ ld b, c
+ inc b
+ inc de
+ ld c, $0
+.asm_7db25
+ cp c
+ jr z, .asm_7db2d
+ inc c
+ inc hl
+ inc hl
+ jr .asm_7db25
+.asm_7db2d
+ push hl
+ push bc
+ push af
+ ld b, $0
+ ld c, a
+ ld hl, $c026
+ add hl, bc
+ ld a, [$c001]
+ ld [hl], a
+ pop af
+ cp $3
+ jr c, .asm_7db46
+ ld hl, $c02e
+ add hl, bc
+ set 2, [hl]
+.asm_7db46
+ pop bc
+ pop hl
+ ld a, [de] ; get channel pointer
+ ld [hli], a
+ inc de
+ ld a, [de]
+ ld [hli], a
+ inc de
+ inc c
+ dec b
+ ld a, b
+ and a
+ ld a, [de]
+ inc de
+ jr nz, .asm_7db25
+ ld a, [$c001]
+ cp $14
+ jr nc, .asm_7db5f
+ jr .asm_7db89
+.asm_7db5f
+ ld a, [$c001]
+ cp $86
+ jr z, .asm_7db89
+ jr c, .asm_7db6a
+ jr .asm_7db89
+.asm_7db6a
+ ld hl, $c02a
+ ld [hli], a
+ ld [hli], a
+ ld [hli], a
+ ld [hl], a
+ ld hl, $c012 ; sfx noise channel pointer
+ ld de, Noise1f_endchannel
+ ld [hl], e
+ inc hl
+ ld [hl], d ; overwrite pointer to point to endchannel
+ ld a, [$c005]
+ and a
+ jr nz, .asm_7db89
+ ld a, [$FF00+$24]
+ ld [$c005], a
+ ld a, $77
+ ld [$FF00+$24], a
+.asm_7db89
+ ret
+
+Noise1f_endchannel: ; 7db8a (1f:5b8a)
+ endchannel
+
+Unknown_7db8b: ; 7db8b (1f:5b8b)
+ db $10, $15, $1A, $1F ; channels 0-3
+ db $10, $15, $1A, $1F ; channels 4-7
+
+Unknown_7db93: ; 7db93 (1f:5b93)
+ db $EE, $DD, $BB, $77 ; channels 0-3
+ db $EE, $DD, $BB, $77 ; channels 4-7
+
+Unknown_7db9b: ; 7db9b (1f:5b9b)
+ db $11, $22, $44, $88 ; channels 0-3
+ db $11, $22, $44, $88 ; channels 4-7
+
+Unknown_7dba3: ; 7dba3 (1f:5ba3)
+ dw $F82C
+ dw $F89D
+ dw $F907
+ dw $F96B
+ dw $F9CA
+ dw $FA23
+ dw $FA77
+ dw $FAC7
+ dw $FB12
+ dw $FB58
+ dw $FB9B
+ dw $FBDA
+
+