ref: 71090c13497946b739cd13f80d31ee13b464e9e6
dir: /audio/engine_2.asm/
; The second of three duplicated sound engines. Audio2_UpdateMusic:: ld c, Ch0 .loop ld b, $0 ld hl, wChannelSoundIDs add hl, bc ld a, [hl] and a jr z, .nextChannel ld a, c cp Ch4 jr nc, .applyAffects ; if sfx channel ld a, [wMuteAudioAndPauseMusic] and a jr z, .applyAffects bit 7, a jr nz, .nextChannel set 7, a ld [wMuteAudioAndPauseMusic], a xor a ld [rNR51], a ld [rNR30], a ld a, $80 ld [rNR30], a jr .nextChannel .applyAffects call Audio2_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 wChannelFlags1: ; 0: toggleperfectpitch has been used ; 1: call has been used ; 3: a toggle used only by this routine for vibrato ; 4: pitchbend flag ; 6: dutycycle flag Audio2_ApplyMusicAffects: ld b, $0 ld hl, wChannelNoteDelayCounters ; delay until next note add hl, bc ld a, [hl] cp $1 ; if the delay is 1, play next note jp z, Audio2_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, wChannelSoundIDs + Ch4 add hl, bc ld a, [hl] and a jr z, .startChecks ret .startChecks ld hl, wChannelFlags1 add hl, bc bit 6, [hl] ; dutycycle jr z, .checkForExecuteMusic call Audio2_ApplyDutyCycle .checkForExecuteMusic ld b, $0 ld hl, wChannelFlags2 add hl, bc bit 0, [hl] jr nz, .checkForPitchBend ld hl, wChannelFlags1 add hl, bc bit 2, [hl] jr nz, .disablePitchBendVibrato .checkForPitchBend ld hl, wChannelFlags1 add hl, bc bit 4, [hl] ; pitchbend jr z, .checkVibratoDelay jp Audio2_ApplyPitchBend .checkVibratoDelay ld hl, wChannelVibratoDelayCounters ; 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, wChannelVibratoExtents ; vibrato rate add hl, bc ld a, [hl] and a jr nz, .vibrato ret ; no vibrato .vibrato ld d, a ld hl, wChannelVibratoRates 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, wChannelFrequencyLowBytes add hl, bc ld e, [hl] ; get note pitch ld hl, wChannelFlags1 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 Audio2_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 Audio2_PlayNextNote: ld hl, wChannelVibratoDelayCounterReloadValues add hl, bc ld a, [hl] ld hl, wChannelVibratoDelayCounters add hl, bc ld [hl], a ld hl, wChannelFlags1 add hl, bc res 4, [hl] res 5, [hl] ld a, c cp Ch4 jr nz, .beginChecks ld a, [wLowHealthAlarm] ;low health alarm enabled? bit 7, a ret nz .beginChecks call Audio2_endchannel ret Audio2_endchannel: call Audio2_GetNextMusicByte ld d, a cp $ff ; is this command an endchannel? jp nz, Audio2_callchannel ; no ld b, $0 ; yes ld hl, wChannelFlags1 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, wChannelFlags2 add hl, bc res 0, [hl] cp Ch6 jr nz, .notSfxChannel3 ld a, $0 ld [rNR30], a ld a, $80 ld [rNR30], a .notSfxChannel3 jr nz, .asm_219a3 ld a, [wDisableChannelOutputWhenSfxEnds] and a jr z, .asm_219a3 xor a ld [wDisableChannelOutputWhenSfxEnds], 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, wChannelCommandPointers add hl, de push hl ; store current channel address ld hl, wChannelReturnAddresses 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 Audio2_endchannel .asm_219c0 ld hl, Unknown_222de add hl, bc ld a, [rNR51] and [hl] ld [rNR51], a .asm_219c9 ld a, [wChannelSoundIDs + Ch4] cp $14 jr nc, .asm_219d2 jr .asm_219ef .asm_219d2 ld a, [wChannelSoundIDs + Ch4] 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 Audio2_21e6d ret c .asm_219e6 ld a, [wSavedVolume] ld [rNR50], a xor a ld [wSavedVolume], a .asm_219ef ld hl, wChannelSoundIDs add hl, bc ld [hl], b ret Audio2_callchannel: cp $fd ; is this command a callchannel? jp nz, Audio2_loopchannel ; no call Audio2_GetNextMusicByte ; yes push af call Audio2_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, wChannelCommandPointers add hl, de push hl ld hl, wChannelReturnAddresses 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, wChannelFlags1 add hl, bc set 1, [hl] ; set the call flag jp Audio2_endchannel Audio2_loopchannel: cp $fe ; is this command a loopchannel? jp nz, Audio2_notetype ; no call Audio2_GetNextMusicByte ; yes ld e, a and a jr z, .infiniteLoop ld b, $0 ld hl, wChannelLoopCounters add hl, bc ld a, [hl] cp e jr nz, .loopAgain ld a, $1 ; if no more loops to make, ld [hl], a call Audio2_GetNextMusicByte ; skip pointer call Audio2_GetNextMusicByte jp Audio2_endchannel .loopAgain ; inc loop count inc a ld [hl], a ; fall through .infiniteLoop ; overwrite current address with pointer call Audio2_GetNextMusicByte push af call Audio2_GetNextMusicByte ld b, a ld d, $0 ld a, c add a ld e, a ld hl, wChannelCommandPointers add hl, de pop af ld [hli], a ld [hl], b jp Audio2_endchannel Audio2_notetype: and $f0 cp $d0 ; is this command a notetype? jp nz, Audio2_toggleperfectpitch ; no ld a, d ; yes and $f ld b, $0 ld hl, wChannelNoteSpeeds 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 Audio2_GetNextMusicByte ld d, a ld a, c cp Ch2 jr z, .musicChannel3 cp Ch6 jr nz, .notChannel3 ld hl, wSfxWaveInstrument jr .sfxChannel3 .musicChannel3 ld hl, wMusicWaveInstrument .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, wChannelVolumes add hl, bc ld [hl], d .noiseChannel jp Audio2_endchannel Audio2_toggleperfectpitch: ld a, d cp $e8 ; is this command a toggleperfectpitch? jr nz, Audio2_vibrato ; no ld b, $0 ; yes ld hl, wChannelFlags1 add hl, bc ld a, [hl] xor $1 ld [hl], a ; flip bit 0 of wChannelFlags1 jp Audio2_endchannel Audio2_vibrato: cp $ea ; is this command a vibrato? jr nz, Audio2_pitchbend ; no call Audio2_GetNextMusicByte ; yes ld b, $0 ld hl, wChannelVibratoDelayCounters add hl, bc ld [hl], a ; store delay ld hl, wChannelVibratoDelayCounterReloadValues add hl, bc ld [hl], a ; store delay call Audio2_GetNextMusicByte ld d, a and $f0 swap a ld b, $0 ld hl, wChannelVibratoExtents 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, wChannelVibratoRates add hl, bc swap a or d ld [hl], a ; store depth as both high and low nibbles jp Audio2_endchannel Audio2_pitchbend: cp $eb ; is this command a pitchbend? jr nz, Audio2_duty ; no call Audio2_GetNextMusicByte ; yes ld b, $0 ld hl, wChannelPitchBendLengthModifiers add hl, bc ld [hl], a ; store first param call Audio2_GetNextMusicByte ld d, a and $f0 swap a ld b, a ld a, d and $f call Audio2_22017 ld b, $0 ld hl, wChannelPitchBendTargetFrequencyHighBytes add hl, bc ld [hl], d ; store unknown part of second param ld hl, wChannelPitchBendTargetFrequencyLowBytes add hl, bc ld [hl], e ; store unknown part of second param ld b, $0 ld hl, wChannelFlags1 add hl, bc set 4, [hl] ; set pitchbend flag call Audio2_GetNextMusicByte ld d, a jp Audio2_notelength Audio2_duty: cp $ec ; is this command a duty? jr nz, Audio2_tempo ; no call Audio2_GetNextMusicByte ; yes rrca rrca and $c0 ld b, $0 ld hl, wChannelDuties add hl, bc ld [hl], a ; store duty jp Audio2_endchannel Audio2_tempo: cp $ed ; is this command a tempo? jr nz, Audio2_stereopanning ; no ld a, c ; yes cp Ch4 jr nc, .sfxChannel call Audio2_GetNextMusicByte ld [wMusicTempo], a ; store first param call Audio2_GetNextMusicByte ld [wMusicTempo + 1], a ; store second param xor a ld [wChannelNoteDelayCountersFractionalPart], a ; clear RAM ld [wChannelNoteDelayCountersFractionalPart + 1], a ld [wChannelNoteDelayCountersFractionalPart + 2], a ld [wChannelNoteDelayCountersFractionalPart + 3], a jr .musicChannelDone .sfxChannel call Audio2_GetNextMusicByte ld [wSfxTempo], a ; store first param call Audio2_GetNextMusicByte ld [wSfxTempo + 1], a ; store second param xor a ld [wChannelNoteDelayCountersFractionalPart + 4], a ; clear RAM ld [wChannelNoteDelayCountersFractionalPart + 5], a ld [wChannelNoteDelayCountersFractionalPart + 6], a ld [wChannelNoteDelayCountersFractionalPart + 7], a .musicChannelDone jp Audio2_endchannel Audio2_stereopanning: cp $ee ; is this command a stereopanning? jr nz, Audio2_unknownmusic0xef ; no call Audio2_GetNextMusicByte ; yes ld [wStereoPanning], a ; store panning jp Audio2_endchannel ; this appears to never be used Audio2_unknownmusic0xef: cp $ef ; is this command an unknownmusic0xef? jr nz, Audio2_dutycycle ; no call Audio2_GetNextMusicByte ; yes push bc call Audio2_PlaySound pop bc ld a, [wDisableChannelOutputWhenSfxEnds] and a jr nz, .skip ld a, [wChannelSoundIDs + Ch7] ld [wDisableChannelOutputWhenSfxEnds], a xor a ld [wChannelSoundIDs + Ch7], a .skip jp Audio2_endchannel Audio2_dutycycle: cp $fc ; is this command a dutycycle? jr nz, Audio2_volume ; no call Audio2_GetNextMusicByte ; yes ld b, $0 ld hl, wChannelDutyCycles add hl, bc ld [hl], a ; store full cycle and $c0 ld hl, wChannelDuties add hl, bc ld [hl], a ; store first duty ld hl, wChannelFlags1 add hl, bc set 6, [hl] ; set dutycycle flag jp Audio2_endchannel Audio2_volume: cp $f0 ; is this command a volume? jr nz, Audio2_executemusic ; no call Audio2_GetNextMusicByte ; yes ld [rNR50], a ; store volume jp Audio2_endchannel Audio2_executemusic: cp $f8 ; is this command an executemusic? jr nz, Audio2_octave ; no ld b, $0 ; yes ld hl, wChannelFlags2 add hl, bc set 0, [hl] jp Audio2_endchannel Audio2_octave: and $f0 cp $e0 ; is this command an octave? jr nz, Audio2_sfxnote ; no ld hl, wChannelOctaves ; yes ld b, $0 add hl, bc ld a, d and $f ld [hl], a ; store low nibble as octave jp Audio2_endchannel ; sfxnote is either squarenote or noisenote depending on the channel Audio2_sfxnote: cp $20 ; is this command an sfxnote? jr nz, Audio2_pitchenvelope ; no ld a, c cp Ch3 ; is this a noise or sfx channel? jr c, Audio2_pitchenvelope ; no ld b, $0 ld hl, wChannelFlags2 add hl, bc bit 0, [hl] jr nz, Audio2_pitchenvelope ; no call Audio2_notelength ld d, a ld b, $0 ld hl, wChannelDuties add hl, bc ld a, [hl] or d ld d, a ld b, $1 call Audio2_21ff7 ld [hl], d call Audio2_GetNextMusicByte ld d, a ld b, $2 call Audio2_21ff7 ld [hl], d call Audio2_GetNextMusicByte ld e, a ld a, c cp Ch7 ld a, $0 jr z, .sfxNoiseChannel ; only two params for noise channel push de call Audio2_GetNextMusicByte pop de .sfxNoiseChannel ld d, a push de call Audio2_21daa call Audio2_21d79 pop de call Audio2_21dcc ret Audio2_pitchenvelope: ld a, c cp Ch4 jr c, Audio2_note ; if not a sfx ld a, d cp $10 ; is this command a pitchenvelope? jr nz, Audio2_note ; no ld b, $0 ld hl, wChannelFlags2 add hl, bc bit 0, [hl] jr nz, Audio2_note ; no call Audio2_GetNextMusicByte ; yes ld [rNR10], a jp Audio2_endchannel Audio2_note: ld a, c cp Ch3 jr nz, Audio2_notelength ; if not noise channel ld a, d and $f0 cp $b0 ; is this command a dnote? jr z, Audio2_dnote ; yes jr nc, Audio2_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 Audio2_dnote: ld a, d and $f push af push bc call Audio2_GetNextMusicByte ; get dnote instrument asm_21c7e ld d, a ld a, [wDisableChannelOutputWhenSfxEnds] and a jr nz, .asm_21c89 ld a, d call Audio2_PlaySound .asm_21c89 pop bc pop de Audio2_notelength: 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, wChannelNoteSpeeds add hl, bc ld a, [hl] ld l, b call Audio2_22006 ld a, c cp Ch4 jr nc, .sfxChannel ld a, [wMusicTempo] ld d, a ld a, [wMusicTempo + 1] ld e, a jr .skip .sfxChannel ld d, $1 ld e, $0 cp Ch7 jr z, .skip ; if noise channel call Audio2_21e2f ld a, [wSfxTempo] ld d, a ld a, [wSfxTempo + 1] ld e, a .skip ld a, l ld b, $0 ld hl, wChannelNoteDelayCountersFractionalPart add hl, bc ld l, [hl] call Audio2_22006 ld e, l ld d, h ld hl, wChannelNoteDelayCountersFractionalPart add hl, bc ld [hl], e ld a, d ld hl, wChannelNoteDelayCounters add hl, bc ld [hl], a ld hl, wChannelFlags2 add hl, bc bit 0, [hl] jr nz, Audio2_notepitch ld hl, wChannelFlags1 add hl, bc bit 2, [hl] jr z, Audio2_notepitch pop hl ret Audio2_notepitch: pop af and $f0 cp $c0 ; compare to rest jr nz, .notRest ld a, c cp Ch4 jr nc, .sfxChannel ld hl, wChannelSoundIDs + Ch4 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, [rNR51] and [hl] ld [rNR51], a jr .done .notSfxChannel3 ld b, $2 call Audio2_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, wChannelOctaves add hl, bc ld b, [hl] call Audio2_22017 ld b, $0 ld hl, wChannelFlags1 add hl, bc bit 4, [hl] jr z, .asm_21d39 call Audio2_21f4e .asm_21d39 push de ld a, c cp Ch4 jr nc, .skip ; if sfx channel ld hl, wChannelSoundIDs + Ch4 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, wChannelVolumes add hl, bc ld d, [hl] ld b, $2 call Audio2_21ff7 ld [hl], d call Audio2_21daa call Audio2_21d79 pop de ld b, $0 ld hl, wChannelFlags1 add hl, bc bit 0, [hl] ; has toggleperfectpitch been used? jr z, .skip2 inc e ; if yes, increment the pitch by 1 jr nc, .skip2 inc d .skip2 ld hl, wChannelFrequencyLowBytes add hl, bc ld [hl], e call Audio2_21dcc ret Audio2_21d79: ld b, $0 ld hl, Unknown_222e6 add hl, bc ld a, [rNR51] or [hl] ld d, a ld a, c cp Ch7 jr z, .sfxNoiseChannel cp Ch4 jr nc, .skip ; if sfx channel ld hl, wChannelSoundIDs + Ch4 add hl, bc ld a, [hl] and a jr nz, .skip .sfxNoiseChannel ld a, [wStereoPanning] ld hl, Unknown_222e6 add hl, bc and [hl] ld d, a ld a, [rNR51] ld hl, Unknown_222de add hl, bc and [hl] or d ld d, a .skip ld a, d ld [rNR51], a ret Audio2_21daa: ld b, $0 ld hl, wChannelNoteDelayCounters 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, wChannelDuties add hl, bc ld a, [hl] or d ld d, a .channel3 ld b, $1 call Audio2_21ff7 ld [hl], d ret Audio2_21dcc: ld a, c cp Ch2 jr z, .channel3 cp Ch6 jr nz, .notSfxChannel3 ; fall through .channel3 push de ld de, wMusicWaveInstrument cp Ch2 jr z, .musicChannel3 ld de, wSfxWaveInstrument .musicChannel3 ld a, [de] add a ld d, $0 ld e, a ld hl, Audio2_WavePointers add hl, de ld e, [hl] inc hl ld d, [hl] ld hl, $ff30 ld b, $f ld a, $0 ld [rNR30], a .loop ld a, [de] inc de ld [hli], a ld a, b dec b and a jr nz, .loop ld a, $80 ld [rNR30], a pop de .notSfxChannel3 ld a, d or $80 and $c7 ld d, a ld b, $3 call Audio2_21ff7 ld [hl], e inc hl ld [hl], d ld a, c cp Ch4 jr c, .musicChannel call Audio2_21e56 .musicChannel ret Audio2_21e19: ld a, c cp Ch4 jr nz, .asm_21e2e ld a, [wLowHealthAlarm] bit 7, a jr z, .asm_21e2e xor a ld [wFrequencyModifier], a ld a, $80 ld [wTempoModifier], a .asm_21e2e ret Audio2_21e2f: call Audio2_21e8b jr c, .asm_21e39 call Audio2_21e9f jr nc, .asm_21e4c .asm_21e39 ld d, $0 ld a, [wTempoModifier] add $80 jr nc, .asm_21e43 inc d .asm_21e43 ld [wSfxTempo + 1], a ld a, d ld [wSfxTempo], a jr .asm_21e55 .asm_21e4c xor a ld [wSfxTempo + 1], a ld a, $1 ld [wSfxTempo], a .asm_21e55 ret Audio2_21e56: call Audio2_21e8b jr c, .asm_21e60 call Audio2_21e9f jr nc, .asm_21e6c .asm_21e60 ld a, [wFrequencyModifier] 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 Audio2_21e6d: call Audio2_21e8b jr nc, .asm_21e88 ld hl, wChannelCommandPointers 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 Audio2_21e8b: ld a, [wChannelSoundIDs + Ch4] 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 Audio2_21e9f: ld a, [wChannelSoundIDs + Ch7] ld b, a ld a, [wChannelSoundIDs + Ch4] 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 Audio2_ApplyPitchBend: ld hl, wChannelFlags1 add hl, bc bit 5, [hl] jp nz, .asm_21eff ld hl, wChannelPitchBendCurrentFrequencyLowBytes add hl, bc ld e, [hl] ld hl, wChannelPitchBendCurrentFrequencyHighBytes add hl, bc ld d, [hl] ld hl, wChannelPitchBendFrequencySteps add hl, bc ld l, [hl] ld h, b add hl, de ld d, h ld e, l ld hl, wChannelPitchBendCurrentFrequencyFractionalPart add hl, bc push hl ld hl, wChannelPitchBendFrequencyStepsFractionalPart 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, wChannelPitchBendTargetFrequencyHighBytes add hl, bc ld a, [hl] cp d jp c, .asm_21f45 jr nz, .asm_21f32 ld hl, wChannelPitchBendTargetFrequencyLowBytes add hl, bc ld a, [hl] cp e jp c, .asm_21f45 jr .asm_21f32 .asm_21eff ld hl, wChannelPitchBendCurrentFrequencyLowBytes add hl, bc ld a, [hl] ld hl, wChannelPitchBendCurrentFrequencyHighBytes add hl, bc ld d, [hl] ld hl, wChannelPitchBendFrequencySteps add hl, bc ld e, [hl] sub e ld e, a ld a, d sbc b ld d, a ld hl, wChannelPitchBendFrequencyStepsFractionalPart 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, wChannelPitchBendTargetFrequencyHighBytes add hl, bc ld a, d cp [hl] jr c, .asm_21f45 jr nz, .asm_21f32 ld hl, wChannelPitchBendTargetFrequencyLowBytes add hl, bc ld a, e cp [hl] jr c, .asm_21f45 .asm_21f32 ld hl, wChannelPitchBendCurrentFrequencyLowBytes add hl, bc ld [hl], e ld hl, wChannelPitchBendCurrentFrequencyHighBytes add hl, bc ld [hl], d ld b, $3 call Audio2_21ff7 ld a, e ld [hli], a ld [hl], d ret .asm_21f45 ld hl, wChannelFlags1 add hl, bc res 4, [hl] res 5, [hl] ret Audio2_21f4e: ld hl, wChannelPitchBendCurrentFrequencyHighBytes add hl, bc ld [hl], d ld hl, wChannelPitchBendCurrentFrequencyLowBytes add hl, bc ld [hl], e ld hl, wChannelNoteDelayCounters add hl, bc ld a, [hl] ld hl, wChannelPitchBendLengthModifiers add hl, bc sub [hl] jr nc, .asm_21f66 ld a, $1 .asm_21f66 ld [hl], a ld hl, wChannelPitchBendTargetFrequencyLowBytes add hl, bc ld a, e sub [hl] ld e, a ld a, d sbc b ld hl, wChannelPitchBendTargetFrequencyHighBytes add hl, bc sub [hl] jr c, .asm_21f82 ld d, a ld b, $0 ld hl, wChannelFlags1 add hl, bc set 5, [hl] jr .asm_21fa5 .asm_21f82 ld hl, wChannelPitchBendCurrentFrequencyHighBytes add hl, bc ld d, [hl] ld hl, wChannelPitchBendCurrentFrequencyLowBytes add hl, bc ld e, [hl] ld hl, wChannelPitchBendTargetFrequencyLowBytes add hl, bc ld a, [hl] sub e ld e, a ld a, d sbc b ld d, a ld hl, wChannelPitchBendTargetFrequencyHighBytes add hl, bc ld a, [hl] sub d ld d, a ld b, $0 ld hl, wChannelFlags1 add hl, bc res 5, [hl] .asm_21fa5 ld hl, wChannelPitchBendLengthModifiers 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, wChannelPitchBendFrequencySteps add hl, bc ld [hl], d ld hl, wChannelPitchBendFrequencyStepsFractionalPart add hl, bc ld [hl], a ld hl, wChannelPitchBendCurrentFrequencyFractionalPart add hl, bc ld [hl], a ret Audio2_ApplyDutyCycle: ld b, $0 ld hl, wChannelDutyCycles add hl, bc ld a, [hl] rlca rlca ld [hl], a and $c0 ld d, a ld b, $1 call Audio2_21ff7 ld a, [hl] and $3f or d ld [hl], a ret Audio2_GetNextMusicByte: ld d, $0 ld a, c add a ld e, a ld hl, wChannelCommandPointers 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 Audio2_21ff7: 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 Audio2_22006: 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 Audio2_22017: ld h, $0 ld l, a add hl, hl ld d, h ld e, l ld hl, Audio2_Pitches 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 Audio2_PlaySound:: ld [wSoundID], a cp $ff jp z, Audio2_221f3 cp $e9 jp z, Audio2_2210d jp c, Audio2_2210d cp $fe jr z, .asm_2204c jp nc, Audio2_2210d .asm_2204c xor a ld [wUnusedC000], a ld [wDisableChannelOutputWhenSfxEnds], a ld [wMusicTempo + 1], a ld [wMusicWaveInstrument], a ld [wSfxWaveInstrument], a ld d, $8 ld hl, wChannelReturnAddresses call FillAudioRAM2 ld hl, wChannelCommandPointers call FillAudioRAM2 ld d, $4 ld hl, wChannelSoundIDs call FillAudioRAM2 ld hl, wChannelFlags1 call FillAudioRAM2 ld hl, wChannelDuties call FillAudioRAM2 ld hl, wChannelDutyCycles call FillAudioRAM2 ld hl, wChannelVibratoDelayCounters call FillAudioRAM2 ld hl, wChannelVibratoExtents call FillAudioRAM2 ld hl, wChannelVibratoRates call FillAudioRAM2 ld hl, wChannelFrequencyLowBytes call FillAudioRAM2 ld hl, wChannelVibratoDelayCounterReloadValues call FillAudioRAM2 ld hl, wChannelFlags2 call FillAudioRAM2 ld hl, wChannelPitchBendLengthModifiers call FillAudioRAM2 ld hl, wChannelPitchBendFrequencySteps call FillAudioRAM2 ld hl, wChannelPitchBendFrequencyStepsFractionalPart call FillAudioRAM2 ld hl, wChannelPitchBendCurrentFrequencyFractionalPart call FillAudioRAM2 ld hl, wChannelPitchBendCurrentFrequencyHighBytes call FillAudioRAM2 ld hl, wChannelPitchBendCurrentFrequencyLowBytes call FillAudioRAM2 ld hl, wChannelPitchBendTargetFrequencyHighBytes call FillAudioRAM2 ld hl, wChannelPitchBendTargetFrequencyLowBytes call FillAudioRAM2 ld a, $1 ld hl, wChannelLoopCounters call FillAudioRAM2 ld hl, wChannelNoteDelayCounters call FillAudioRAM2 ld hl, wChannelNoteSpeeds call FillAudioRAM2 ld [wMusicTempo], a ld a, $ff ld [wStereoPanning], a xor a ld [rNR50], a ld a, $8 ld [rNR10], a ld a, $0 ld [rNR51], a xor a ld [rNR30], a ld a, $80 ld [rNR30], a ld a, $77 ld [rNR50], a jp Audio2_2224e Audio2_2210d: ld l, a ld e, a ld h, $0 ld d, h add hl, hl add hl, de ld de, SFX_Headers_2 add hl, de ld a, h ld [wSfxHeaderPointer], a ld a, l ld [wSfxHeaderPointer + 1], 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, [wSfxHeaderPointer] ld h, a ld a, [wSfxHeaderPointer + 1] ld l, a add hl, bc ld c, d ld a, [hl] and $f ld e, a ld d, $0 ld hl, wChannelSoundIDs add hl, de ld a, [hl] and a jr z, .asm_22162 ld a, e cp $7 jr nz, .asm_22159 ld a, [wSoundID] 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, [wSoundID] 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, wChannelReturnAddresses add hl, de ld [hli], a ld [hl], a ld hl, wChannelCommandPointers add hl, de ld [hli], a ld [hl], a pop de ld hl, wChannelSoundIDs add hl, de ld [hl], a ld hl, wChannelFlags1 add hl, de ld [hl], a ld hl, wChannelDuties add hl, de ld [hl], a ld hl, wChannelDutyCycles add hl, de ld [hl], a ld hl, wChannelVibratoDelayCounters add hl, de ld [hl], a ld hl, wChannelVibratoExtents add hl, de ld [hl], a ld hl, wChannelVibratoRates add hl, de ld [hl], a ld hl, wChannelFrequencyLowBytes add hl, de ld [hl], a ld hl, wChannelVibratoDelayCounterReloadValues add hl, de ld [hl], a ld hl, wChannelPitchBendLengthModifiers add hl, de ld [hl], a ld hl, wChannelPitchBendFrequencySteps add hl, de ld [hl], a ld hl, wChannelPitchBendFrequencyStepsFractionalPart add hl, de ld [hl], a ld hl, wChannelPitchBendCurrentFrequencyFractionalPart add hl, de ld [hl], a ld hl, wChannelPitchBendCurrentFrequencyHighBytes add hl, de ld [hl], a ld hl, wChannelPitchBendCurrentFrequencyLowBytes add hl, de ld [hl], a ld hl, wChannelPitchBendTargetFrequencyHighBytes add hl, de ld [hl], a ld hl, wChannelPitchBendTargetFrequencyLowBytes add hl, de ld [hl], a ld hl, wChannelFlags2 add hl, de ld [hl], a ld a, $1 ld hl, wChannelLoopCounters add hl, de ld [hl], a ld hl, wChannelNoteDelayCounters add hl, de ld [hl], a ld hl, wChannelNoteSpeeds add hl, de ld [hl], a ld a, e cp $4 jr nz, .asm_221ea ld a, $8 ld [rNR10], a .asm_221ea ld a, c and a jp z, Audio2_2224e dec c jp .asm_22126 Audio2_221f3: ld a, $80 ld [rNR52], a ld [rNR30], a xor a ld [rNR51], a ld [rNR32], a ld a, $8 ld [rNR10], a ld [rNR12], a ld [rNR22], a ld [rNR42], a ld a, $40 ld [rNR14], a ld [rNR24], a ld [rNR44], a ld a, $77 ld [rNR50], a xor a ld [wUnusedC000], a ld [wDisableChannelOutputWhenSfxEnds], a ld [wMuteAudioAndPauseMusic], a ld [wMusicTempo + 1], a ld [wSfxTempo + 1], a ld [wMusicWaveInstrument], a ld [wSfxWaveInstrument], a ld d, $a0 ld hl, wChannelCommandPointers call FillAudioRAM2 ld a, $1 ld d, $18 ld hl, wChannelNoteDelayCounters call FillAudioRAM2 ld [wMusicTempo], a ld [wSfxTempo], a ld a, $ff ld [wStereoPanning], a ret ; fills d bytes at hl with a FillAudioRAM2: ld b, d .loop ld [hli], a dec b jr nz, .loop ret Audio2_2224e: ld a, [wSoundID] ld l, a ld e, a ld h, $0 ld d, h add hl, hl add hl, de ld de, SFX_Headers_2 add hl, de ld e, l ld d, h ld hl, wChannelCommandPointers 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, wChannelSoundIDs add hl, bc ld a, [wSoundID] ld [hl], a pop af cp $3 jr c, .asm_22291 ld hl, wChannelFlags1 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, [wSoundID] cp $14 jr nc, .asm_222aa jr .asm_222d4 .asm_222aa ld a, [wSoundID] cp $86 jr z, .asm_222d4 jr c, .asm_222b5 jr .asm_222d4 .asm_222b5 ld hl, wChannelSoundIDs + Ch4 ld [hli], a ld [hli], a ld [hli], a ld [hl], a ld hl, wChannelCommandPointers + Ch6 * 2 ; sfx noise channel pointer ld de, Noise2_endchannel ld [hl], e inc hl ld [hl], d ; overwrite pointer to point to endchannel ld a, [wSavedVolume] and a jr nz, .asm_222d4 ld a, [rNR50] ld [wSavedVolume], a ld a, $77 ld [rNR50], a .asm_222d4 ret Noise2_endchannel: endchannel Unknown_222d6: db $10, $15, $1A, $1F ; channels 0-3 db $10, $15, $1A, $1F ; channels 4-7 Unknown_222de: db $EE, $DD, $BB, $77 ; channels 0-3 db $EE, $DD, $BB, $77 ; channels 4-7 Unknown_222e6: db $11, $22, $44, $88 ; channels 0-3 db $11, $22, $44, $88 ; channels 4-7 Audio2_Pitches: dw $F82C ; C_ dw $F89D ; C# dw $F907 ; D_ dw $F96B ; D# dw $F9CA ; E_ dw $FA23 ; F_ dw $FA77 ; F# dw $FAC7 ; G_ dw $FB12 ; G# dw $FB58 ; A_ dw $FB9B ; A# dw $FBDA ; B_