ref: 08891da82254aa4051bf594d4abc2db8e4043d8f
dir: /audio/engine.asm/
; The entire sound engine. Uses section "audio" in WRAM. ; Interfaces are in bank 0. ; Notable functions: ; FadeMusic ; PlayStereoSFX _MapSetup_Sound_Off:: ; e8000 ; restart sound operation ; clear all relevant hardware registers & wram push hl push de push bc push af call MusicOff ld hl, rNR50 ; channel control registers xor a ld [hli], a ; rNR50 ; volume/vin ld [hli], a ; rNR51 ; sfx channels ld a, $80 ; all channels on ld [hli], a ; ff26 ; music channels ld hl, rNR10 ; sound channel registers ld e, NUM_MUSIC_CHANS .clearsound ; sound channel 1 2 3 4 xor a ld [hli], a ; rNR10, rNR20, rNR30, rNR40 ; sweep = 0 ld [hli], a ; rNR11, rNR21, rNR31, rNR41 ; length/wavepattern = 0 ld a, $8 ld [hli], a ; rNR12, rNR22, rNR32, rNR42 ; envelope = 0 xor a ld [hli], a ; rNR13, rNR23, rNR33, rNR43 ; frequency lo = 0 ld a, $80 ld [hli], a ; rNR14, rNR24, rNR34, rNR44 ; restart sound (freq hi = 0) dec e jr nz, .clearsound ld hl, Channels ; start of channel data ld de, ChannelsEnd - Channels ; length of area to clear (entire sound wram area) .clearchannels xor a ld [hli], a dec de ld a, e or d jr nz, .clearchannels ld a, MAX_VOLUME ld [Volume], a call MusicOn pop af pop bc pop de pop hl ret ; e803d MusicFadeRestart: ; e803d ; restart but keep the music id to fade in to ld a, [MusicFadeID + 1] push af ld a, [MusicFadeID] push af call _MapSetup_Sound_Off pop af ld [MusicFadeID], a pop af ld [MusicFadeID + 1], a ret ; e8051 MusicOn: ; e8051 ld a, 1 ld [MusicPlaying], a ret ; e8057 MusicOff: ; e8057 xor a ld [MusicPlaying], a ret ; e805c _UpdateSound:: ; e805c ; called once per frame ; no use updating audio if it's not playing ld a, [MusicPlaying] and a ret z ; start at ch1 xor a ld [CurChannel], a ; just ld [SoundOutput], a ; off ld bc, Channel1 .loop ; is the channel active? ld hl, Channel1Flags - Channel1 add hl, bc bit SOUND_CHANNEL_ON, [hl] jp z, .nextchannel ; check time left in the current note ld hl, Channel1NoteDuration - Channel1 add hl, bc ld a, [hl] cp $2 ; 1 or 0? jr c, .noteover dec [hl] jr .continue_sound_update .noteover ; reset vibrato delay ld hl, Channel1VibratoDelay - Channel1 add hl, bc ld a, [hl] ld hl, Channel1VibratoDelayCount - Channel1 add hl, bc ld [hl], a ; turn vibrato off for now ld hl, Channel1Flags2 - Channel1 add hl, bc res SOUND_PITCH_WHEEL, [hl] ; get next note call ParseMusic .continue_sound_update call ApplyPitchWheel ; duty cycle ld hl, Channel1DutyCycle - Channel1 add hl, bc ld a, [hli] ld [wCurTrackDuty], a ; intensity ld a, [hli] ld [wCurTrackIntensity], a ; frequency ld a, [hli] ld [wCurTrackFrequency], a ld a, [hl] ld [wCurTrackFrequency + 1], a ; vibrato, noise call HandleTrackVibrato ; handle vibrato and other things call HandleNoise ; turn off music when playing sfx? ld a, [SFXPriority] and a jr z, .next ; are we in a sfx channel right now? ld a, [CurChannel] cp CHAN5 jr nc, .next ; are any sfx channels active? ; if so, mute ld hl, Channel5Flags bit SOUND_CHANNEL_ON, [hl] jr nz, .restnote ld hl, Channel6Flags bit SOUND_CHANNEL_ON, [hl] jr nz, .restnote ld hl, Channel7Flags bit SOUND_CHANNEL_ON, [hl] jr nz, .restnote ld hl, Channel8Flags bit SOUND_CHANNEL_ON, [hl] jr z, .next .restnote ld hl, Channel1NoteFlags - Channel1 add hl, bc set NOTE_REST, [hl] ; Rest .next ; are we in a sfx channel right now? ld a, [CurChannel] cp CHAN5 jr nc, .sfx_channel ld hl, Channel5Flags - Channel1 add hl, bc bit SOUND_CHANNEL_ON, [hl] jr nz, .sound_channel_on .sfx_channel call UpdateChannels ld hl, Channel1Tracks - Channel1 add hl, bc ld a, [SoundOutput] or [hl] ld [SoundOutput], a .sound_channel_on ; clear note flags ld hl, Channel1NoteFlags - Channel1 add hl, bc xor a ld [hl], a .nextchannel ; next channel ld hl, Channel2 - Channel1 add hl, bc ld c, l ld b, h ld a, [CurChannel] inc a ld [CurChannel], a cp $8 ; are we done? jp nz, .loop ; do it all again call PlayDanger ; fade music in/out call FadeMusic ; write volume to hardware register ld a, [Volume] ld [rNR50], a ; write SO on/off to hardware register ld a, [SoundOutput] ld [rNR51], a ret ; e8125 UpdateChannels: ; e8125 ld hl, .ChannelFnPtrs ld a, [CurChannel] and $7 add a ld e, a ld d, 0 add hl, de ld a, [hli] ld h, [hl] ld l, a jp hl .ChannelFnPtrs: dw .Channel1 dw .Channel2 dw .Channel3 dw .Channel4 ; sfx ch ptrs are identical to music chs ; ..except 5 dw .Channel5 dw .Channel6 dw .Channel7 dw .Channel8 .Channel1: ld a, [Danger] bit DANGER_ON_F, a ret nz .Channel5: ld hl, Channel1NoteFlags - Channel1 add hl, bc bit NOTE_UNKN_3, [hl] jr z, .asm_e8159 ; ld a, [SoundInput] ld [rNR10], a .asm_e8159 bit NOTE_REST, [hl] ; rest jr nz, .ch1rest bit NOTE_NOISE_SAMPLING, [hl] jr nz, .asm_e81a2 bit NOTE_FREQ_OVERRIDE, [hl] jr nz, .frequency_override bit NOTE_VIBRATO_OVERRIDE, [hl] jr nz, .asm_e8184 jr .check_duty_override .frequency_override ld a, [wCurTrackFrequency] ld [rNR13], a ld a, [wCurTrackFrequency + 1] ld [rNR14], a .check_duty_override bit NOTE_DUTY_OVERRIDE, [hl] ret z ld a, [wCurTrackDuty] ld d, a ld a, [rNR11] and $3f ; sound length or d ld [rNR11], a ret .asm_e8184 ld a, [wCurTrackDuty] ld d, a ld a, [rNR11] and $3f ; sound length or d ld [rNR11], a ld a, [wCurTrackFrequency] ld [rNR13], a ret .ch1rest ld a, [rNR52] and %10001110 ; ch1 off ld [rNR52], a ld hl, rNR10 call ClearChannel ret .asm_e81a2 ld hl, wCurTrackDuty ld a, $3f ; sound length or [hl] ld [rNR11], a ld a, [wCurTrackIntensity] ld [rNR12], a ld a, [wCurTrackFrequency] ld [rNR13], a ld a, [wCurTrackFrequency + 1] or $80 ld [rNR14], a ret .Channel2: .Channel6: ld hl, Channel1NoteFlags - Channel1 add hl, bc bit NOTE_REST, [hl] ; rest jr nz, .ch2rest bit NOTE_NOISE_SAMPLING, [hl] jr nz, .asm_e8204 bit NOTE_VIBRATO_OVERRIDE, [hl] jr nz, .asm_e81e6 bit NOTE_DUTY_OVERRIDE, [hl] ret z ld a, [wCurTrackDuty] ld d, a ld a, [rNR21] and $3f ; sound length or d ld [rNR21], a ret .asm_e81db ; unused ld a, [wCurTrackFrequency] ld [rNR23], a ld a, [wCurTrackFrequency + 1] ld [rNR24], a ret .asm_e81e6 ld a, [wCurTrackDuty] ld d, a ld a, [rNR21] and $3f ; sound length or d ld [rNR21], a ld a, [wCurTrackFrequency] ld [rNR23], a ret .ch2rest ld a, [rNR52] and %10001101 ; ch2 off ld [rNR52], a ld hl, rNR20 call ClearChannel ret .asm_e8204 ld hl, wCurTrackDuty ld a, $3f ; sound length or [hl] ld [rNR21], a ld a, [wCurTrackIntensity] ld [rNR22], a ld a, [wCurTrackFrequency] ld [rNR23], a ld a, [wCurTrackFrequency + 1] or $80 ; initial (restart) ld [rNR24], a ret .Channel3: .Channel7: ld hl, Channel1NoteFlags - Channel1 add hl, bc bit NOTE_REST, [hl] ; rest jr nz, .ch3rest bit NOTE_NOISE_SAMPLING, [hl] jr nz, .asm_e824d bit NOTE_VIBRATO_OVERRIDE, [hl] jr nz, .asm_e823a ret .asm_e822f ; unused ld a, [wCurTrackFrequency] ld [rNR33], a ld a, [wCurTrackFrequency + 1] ld [rNR34], a ret .asm_e823a ld a, [wCurTrackFrequency] ld [rNR33], a ret .ch3rest ld a, [rNR52] and %10001011 ; ch3 off ld [rNR52], a ld hl, rNR30 call ClearChannel ret .asm_e824d ld a, $3f ; sound length ld [rNR31], a xor a ld [rNR30], a call .asm_e8268 ld a, $80 ld [rNR30], a ld a, [wCurTrackFrequency] ld [rNR33], a ld a, [wCurTrackFrequency + 1] or $80 ld [rNR34], a ret .asm_e8268 push hl ld a, [wCurTrackIntensity] and $f ; only 0-9 are valid ld l, a ld h, 0 ; hl << 4 ; each wavepattern is $f bytes long ; so seeking is done in $10s rept 4 add hl, hl endr ld de, WaveSamples add hl, de ; load wavepattern into rWave_0-rWave_f ld a, [hli] ld [rWave_0], a ld a, [hli] ld [rWave_1], a ld a, [hli] ld [rWave_2], a ld a, [hli] ld [rWave_3], a ld a, [hli] ld [rWave_4], a ld a, [hli] ld [rWave_5], a ld a, [hli] ld [rWave_6], a ld a, [hli] ld [rWave_7], a ld a, [hli] ld [rWave_8], a ld a, [hli] ld [rWave_9], a ld a, [hli] ld [rWave_a], a ld a, [hli] ld [rWave_b], a ld a, [hli] ld [rWave_c], a ld a, [hli] ld [rWave_d], a ld a, [hli] ld [rWave_e], a ld a, [hli] ld [rWave_f], a pop hl ld a, [wCurTrackIntensity] and $f0 sla a ld [rNR32], a ret .Channel4: .Channel8: ld hl, Channel1NoteFlags - Channel1 add hl, bc bit NOTE_REST, [hl] ; rest jr nz, .ch4rest bit NOTE_NOISE_SAMPLING, [hl] jr nz, .asm_e82d4 ret .asm_e82c1 ; unused ld a, [wCurTrackFrequency] ld [rNR43], a ret .ch4rest ld a, [rNR52] and %10000111 ; ch4 off ld [rNR52], a ld hl, rNR40 call ClearChannel ret .asm_e82d4 ld a, $3f ; sound length ld [rNR41], a ld a, [wCurTrackIntensity] ld [rNR42], a ld a, [wCurTrackFrequency] ld [rNR43], a ld a, $80 ld [rNR44], a ret ; e82e7 _CheckSFX: ; e82e7 ; return carry if any sfx channels are active ld hl, Channel5Flags bit SOUND_CHANNEL_ON, [hl] jr nz, .sfxon ld hl, Channel6Flags bit SOUND_CHANNEL_ON, [hl] jr nz, .sfxon ld hl, Channel7Flags bit SOUND_CHANNEL_ON, [hl] jr nz, .sfxon ld hl, Channel8Flags bit SOUND_CHANNEL_ON, [hl] jr nz, .sfxon and a ret .sfxon scf ret ; e8307 PlayDanger: ; e8307 ld a, [Danger] bit DANGER_ON_F, a ret z and $ff ^ (1 << DANGER_ON_F) ld d, a call _CheckSFX jr c, .asm_e8335 and a jr z, .asm_e8323 cp 16 ; halfway jr z, .asm_e831e jr .asm_e8335 .asm_e831e ld hl, Tablee8354 jr .updatehw .asm_e8323 ld hl, Tablee8350 .updatehw xor a ld [rNR10], a ; sweep off ld a, [hli] ld [rNR11], a ; sound length / duty cycle ld a, [hli] ld [rNR12], a ; ch1 volume envelope ld a, [hli] ld [rNR13], a ; ch1 frequency lo ld a, [hli] ld [rNR14], a ; ch1 frequency hi .asm_e8335 ld a, d inc a cp 30 jr c, .asm_e833c xor a .asm_e833c or 1 << DANGER_ON_F ld [Danger], a ; is hw ch1 on? ld a, [SoundOutput] and $11 ret nz ; if not, turn it on ld a, [SoundOutput] or $11 ld [SoundOutput], a ret ; e8350 Tablee8350: ; e8350 db $80 ; duty 50% db $e2 ; volume 14, envelope decrease sweep 2 db $50 ; frequency: $750 db $87 ; restart sound ; e8354 Tablee8354: ; e8354 db $80 ; duty 50% db $e2 ; volume 14, envelope decrease sweep 2 db $ee ; frequency: $6ee db $86 ; restart sound ; e8358 FadeMusic: ; e8358 ; fade music if applicable ; usage: ; write to MusicFade ; song fades out at the given rate ; load song id in MusicFadeID ; fade new song in ; notes: ; max # frames per volume level is $3f ; fading? ld a, [MusicFade] and a ret z ; has the count ended? ld a, [MusicFadeCount] and a jr z, .update ; count down dec a ld [MusicFadeCount], a ret .update ld a, [MusicFade] ld d, a ; get new count and $3f ld [MusicFadeCount], a ; get SO1 volume ld a, [Volume] and VOLUME_SO1_LEVEL ; which way are we fading? bit MUSIC_FADE_IN_F, d jr nz, .fadein ; fading out and a jr z, .novolume dec a jr .updatevolume .novolume ; make sure volume is off xor a ld [Volume], a ; did we just get on a bike? ld a, [PlayerState] cp PLAYER_BIKE jr z, .bicycle push bc ; restart sound call MusicFadeRestart ; get new song id ld a, [MusicFadeID] and a jr z, .quit ; this assumes there are fewer than 256 songs! ld e, a ld a, [MusicFadeID + 1] ld d, a ; load new song call _PlayMusic .quit ; cleanup pop bc ; stop fading xor a ld [MusicFade], a ret .bicycle push bc ; restart sound call MusicFadeRestart ; this turns the volume up ; turn it back down xor a ld [Volume], a ; get new song id ld a, [MusicFadeID] ld e, a ld a, [MusicFadeID + 1] ld d, a ; load new song call _PlayMusic pop bc ; fade in ld hl, MusicFade set MUSIC_FADE_IN_F, [hl] ret .fadein ; are we done? cp $7 jr nc, .maxvolume ; inc volume inc a jr .updatevolume .maxvolume ; we're done xor a ld [MusicFade], a ret .updatevolume ; hi = lo ld d, a swap a or d ld [Volume], a ret ; e83d1 LoadNote: ; e83d1 ; wait for pitch wheel to finish ld hl, Channel1Flags2 - Channel1 add hl, bc bit SOUND_PITCH_WHEEL, [hl] ret z ; get note duration ld hl, Channel1NoteDuration - Channel1 add hl, bc ld a, [hl] ld hl, wCurNoteDuration sub [hl] jr nc, .ok ld a, 1 .ok ld [hl], a ; get frequency ld hl, Channel1Frequency - Channel1 add hl, bc ld e, [hl] inc hl ld d, [hl] ; get direction of pitch wheel ld hl, Channel1PitchWheelTarget - Channel1 add hl, bc ld a, e sub [hl] ld e, a ld a, d sbc 0 ld d, a ld hl, Channel1PitchWheelTarget + 1 - Channel1 add hl, bc sub [hl] jr nc, .greater_than ld hl, Channel1Flags3 - Channel1 add hl, bc set SOUND_PITCH_WHEEL_DIR, [hl] ; get frequency ld hl, Channel1Frequency - Channel1 add hl, bc ld e, [hl] inc hl ld d, [hl] ; ???? ld hl, Channel1PitchWheelTarget - Channel1 add hl, bc ld a, [hl] sub e ld e, a ld a, d sbc 0 ld d, a ; ???? ld hl, Channel1PitchWheelTarget + 1 - Channel1 add hl, bc ld a, [hl] sub d ld d, a jr .resume .greater_than ld hl, Channel1Flags3 - Channel1 add hl, bc res SOUND_PITCH_WHEEL_DIR, [hl] ; get frequency ld hl, Channel1Frequency - Channel1 add hl, bc ld e, [hl] inc hl ld d, [hl] ; get distance from pitch wheel target ld hl, Channel1PitchWheelTarget - Channel1 add hl, bc ld a, e sub [hl] ld e, a ld a, d sbc 0 ld d, a ld hl, Channel1PitchWheelTarget + 1 - Channel1 add hl, bc sub [hl] ld d, a .resume ; de = x * [wCurNoteDuration] + y ; x + 1 -> d ; y -> a push bc ld hl, wCurNoteDuration ld b, 0 ; quotient .loop inc b ld a, e sub [hl] ld e, a jr nc, .loop ld a, d and a jr z, .quit dec d jr .loop .quit ld a, e ; remainder add [hl] ld d, b ; quotient pop bc ld hl, Channel1PitchWheelAmount - Channel1 add hl, bc ld [hl], d ; quotient ld hl, Channel1PitchWheelAmountFraction - Channel1 add hl, bc ld [hl], a ; remainder ld hl, Channel1Field25 - Channel1 add hl, bc xor a ld [hl], a ret ; e8466 HandleTrackVibrato: ; e8466 ; handle duty, cry pitch, and vibrato ld hl, Channel1Flags2 - Channel1 add hl, bc bit SOUND_DUTY, [hl] ; duty jr z, .next ld hl, Channel1SFXDutyLoop - Channel1 add hl, bc ld a, [hl] rlca rlca ld [hl], a and $c0 ld [wCurTrackDuty], a ld hl, Channel1NoteFlags - Channel1 add hl, bc set NOTE_DUTY_OVERRIDE, [hl] .next ld hl, Channel1Flags2 - Channel1 add hl, bc bit SOUND_CRY_PITCH, [hl] jr z, .vibrato ld hl, Channel1CryPitch - Channel1 add hl, bc ld e, [hl] inc hl ld d, [hl] ld hl, wCurTrackFrequency ld a, [hli] ld h, [hl] ld l, a add hl, de ld e, l ld d, h ld hl, wCurTrackFrequency ld [hl], e inc hl ld [hl], d .vibrato ; is vibrato on? ld hl, Channel1Flags2 - Channel1 add hl, bc bit SOUND_VIBRATO, [hl] ; vibrato jr z, .quit ; is vibrato active for this note yet? ; is the delay over? ld hl, Channel1VibratoDelayCount - Channel1 add hl, bc ld a, [hl] and a jr nz, .subexit ; is the extent nonzero? ld hl, Channel1VibratoExtent - Channel1 add hl, bc ld a, [hl] and a jr z, .quit ; save it for later ld d, a ; is it time to toggle vibrato up/down? ld hl, Channel1VibratoRate - Channel1 add hl, bc ld a, [hl] and $f ; count jr z, .toggle .subexit dec [hl] jr .quit .toggle ; refresh count ld a, [hl] swap [hl] or [hl] ld [hl], a ; ???? ld a, [wCurTrackFrequency] ld e, a ; toggle vibrato up/down ld hl, Channel1Flags3 - Channel1 add hl, bc bit SOUND_VIBRATO_DIR, [hl] ; vibrato up/down jr z, .down ; up ; vibrato down res SOUND_VIBRATO_DIR, [hl] ; get the delay ld a, d and $f ; lo ; ld d, a ld a, e sub d jr nc, .no_carry ld a, 0 jr .no_carry .down ; vibrato up set SOUND_VIBRATO_DIR, [hl] ; get the delay ld a, d and $f0 ; hi swap a ; move it to lo ; add e jr nc, .no_carry ld a, $ff .no_carry ld [wCurTrackFrequency], a ; ld hl, Channel1NoteFlags - Channel1 add hl, bc set NOTE_VIBRATO_OVERRIDE, [hl] .quit ret ; e84f9 ApplyPitchWheel: ; e84f9 ; quit if pitch wheel inactive ld hl, Channel1Flags2 - Channel1 add hl, bc bit SOUND_PITCH_WHEEL, [hl] ret z ; de = Frequency ld hl, Channel1Frequency - Channel1 add hl, bc ld e, [hl] inc hl ld d, [hl] ; check whether pitch wheel is going up or down ld hl, Channel1Flags3 - Channel1 add hl, bc bit SOUND_PITCH_WHEEL_DIR, [hl] jr z, .decreasing ; frequency += [Channel*PitchWheelAmount] ld hl, Channel1PitchWheelAmount - Channel1 add hl, bc ld l, [hl] ld h, 0 add hl, de ld d, h ld e, l ; [Channel*Field25] += [Channel*PitchWheelAmountFraction] ; if rollover: Frequency += 1 ld hl, Channel1PitchWheelAmountFraction - Channel1 add hl, bc ld a, [hl] ld hl, Channel1Field25 - Channel1 add hl, bc add [hl] ld [hl], a ld a, 0 adc e ld e, a ld a, 0 adc d ld d, a ; Compare the dw at [Channel*PitchWheelTarget] to de. ; If frequency is greater, we're finished. ; Otherwise, load the frequency and set two flags. ld hl, Channel1PitchWheelTarget + 1 - Channel1 add hl, bc ld a, [hl] cp d jp c, .finished_pitch_wheel jr nz, .continue_pitch_wheel ld hl, Channel1PitchWheelTarget - Channel1 add hl, bc ld a, [hl] cp e jp c, .finished_pitch_wheel jr .continue_pitch_wheel .decreasing ; frequency -= [Channel*PitchWheelAmount] ld a, e ld hl, Channel1PitchWheelAmount - Channel1 add hl, bc ld e, [hl] sub e ld e, a ld a, d sbc 0 ld d, a ; [Channel*Field25] *= 2 ; if rollover: Frequency -= 1 ld hl, Channel1PitchWheelAmountFraction - Channel1 add hl, bc ld a, [hl] add a ld [hl], a ld a, e sbc 0 ld e, a ld a, d sbc 0 ld d, a ; Compare the dw at [Channel*PitchWheelTarget] to de. ; If frequency is lower, we're finished. ; Otherwise, load the frequency and set two flags. ld hl, Channel1PitchWheelTarget + 1 - Channel1 add hl, bc ld a, d cp [hl] jr c, .finished_pitch_wheel jr nz, .continue_pitch_wheel ld hl, Channel1PitchWheelTarget - Channel1 add hl, bc ld a, e cp [hl] jr nc, .continue_pitch_wheel .finished_pitch_wheel ld hl, Channel1Flags2 - Channel1 add hl, bc res SOUND_PITCH_WHEEL, [hl] ld hl, Channel1Flags3 - Channel1 add hl, bc res SOUND_PITCH_WHEEL_DIR, [hl] ret .continue_pitch_wheel ld hl, Channel1Frequency - Channel1 add hl, bc ld [hl], e inc hl ld [hl], d ld hl, Channel1NoteFlags - Channel1 add hl, bc set NOTE_FREQ_OVERRIDE, [hl] set NOTE_DUTY_OVERRIDE, [hl] ret ; e858c HandleNoise: ; e858c ; is noise sampling on? ld hl, Channel1Flags - Channel1 add hl, bc bit SOUND_NOISE, [hl] ; noise sampling ret z ; are we in a sfx channel? ld a, [CurChannel] bit 2, a ; sfx jr nz, .next ; is ch8 on? (noise) ld hl, Channel8Flags bit SOUND_CHANNEL_ON, [hl] ; on? jr z, .next ; is ch8 playing noise? bit SOUND_NOISE, [hl] ret nz ; quit if so ; .next ld a, [wNoiseSampleDelay] and a jr z, ReadNoiseSample dec a ld [wNoiseSampleDelay], a ret ; e85af ReadNoiseSample: ; e85af ; sample struct: ; [wx] [yy] [zz] ; w: ? either 2 or 3 ; x: duration ; zz: intensity ; yy: frequency ; de = [NoiseSampleAddress] ld hl, NoiseSampleAddress ld e, [hl] inc hl ld d, [hl] ; is it empty? ld a, e or d jr z, .quit ld a, [de] inc de cp $ff jr z, .quit and $f inc a ld [wNoiseSampleDelay], a ld a, [de] inc de ld [wCurTrackIntensity], a ld a, [de] inc de ld [wCurTrackFrequency], a xor a ld [wCurTrackFrequency + 1], a ld hl, NoiseSampleAddress ld [hl], e inc hl ld [hl], d ld hl, Channel1NoteFlags - Channel1 add hl, bc set NOTE_NOISE_SAMPLING, [hl] ret .quit ret ; e85e1 ParseMusic: ; e85e1 ; parses until a note is read or the song is ended call GetMusicByte ; store next byte in a cp $ff ; is the song over? jr z, .endchannel cp $d0 ; is it a note? jr c, .readnote ; then it's a command .readcommand call ParseMusicCommand jr ParseMusic ; start over .readnote ; CurMusicByte contains current note ; special notes ld hl, Channel1Flags - Channel1 add hl, bc bit SOUND_SFX, [hl] jp nz, ParseSFXOrRest bit SOUND_REST, [hl] ; rest jp nz, ParseSFXOrRest bit SOUND_NOISE, [hl] ; noise sample jp nz, GetNoiseSample ; normal note ; set note duration (bottom nybble) ld a, [CurMusicByte] and $f call SetNoteDuration ; get note pitch (top nybble) ld a, [CurMusicByte] swap a and $f jr z, .rest ; pitch 0-> rest ; update pitch ld hl, Channel1Pitch - Channel1 add hl, bc ld [hl], a ; store pitch in e ld e, a ; store octave in d ld hl, Channel1Octave - Channel1 add hl, bc ld d, [hl] ; update frequency call GetFrequency ld hl, Channel1Frequency - Channel1 add hl, bc ld [hl], e inc hl ld [hl], d ; ???? ld hl, Channel1NoteFlags - Channel1 add hl, bc set NOTE_NOISE_SAMPLING, [hl] jp LoadNote .rest ; note = rest ld hl, Channel1NoteFlags - Channel1 add hl, bc set NOTE_REST, [hl] ; Rest ret .endchannel ; $ff is reached in music data ld hl, Channel1Flags - Channel1 add hl, bc bit SOUND_SUBROUTINE, [hl] ; in a subroutine? jr nz, .readcommand ; execute ld a, [CurChannel] cp CHAN5 jr nc, .chan_5to8 ; ???? ld hl, Channel5Flags - Channel1 add hl, bc bit SOUND_CHANNEL_ON, [hl] jr nz, .ok .chan_5to8 ld hl, Channel1Flags - Channel1 add hl, bc bit SOUND_REST, [hl] call nz, RestoreVolume ; end music ld a, [CurChannel] cp CHAN5 jr nz, .ok ; ???? xor a ld [rNR10], a ; sweep = 0 .ok ; stop playing ; turn channel off ld hl, Channel1Flags - Channel1 add hl, bc res SOUND_CHANNEL_ON, [hl] ; note = rest ld hl, Channel1NoteFlags - Channel1 add hl, bc set NOTE_REST, [hl] ; clear music id & bank ld hl, Channel1MusicID - Channel1 add hl, bc xor a ld [hli], a ; id hi ld [hli], a ; id lo ld [hli], a ; bank ret ; e8679 RestoreVolume: ; e8679 ; ch5 only ld a, [CurChannel] cp CHAN5 ret nz xor a ld hl, Channel6CryPitch ld [hli], a ld [hl], a ld hl, Channel8CryPitch ld [hli], a ld [hl], a ld a, [LastVolume] ld [Volume], a xor a ld [LastVolume], a ld [SFXPriority], a ret ; e8698 ParseSFXOrRest: ; e8698 ; turn noise sampling on ld hl, Channel1NoteFlags - Channel1 add hl, bc set NOTE_NOISE_SAMPLING, [hl] ; noise sample ; update note duration ld a, [CurMusicByte] call SetNoteDuration ; top nybble doesnt matter? ; update intensity from next param call GetMusicByte ld hl, Channel1Intensity - Channel1 add hl, bc ld [hl], a ; update lo frequency from next param call GetMusicByte ld hl, Channel1FrequencyLo - Channel1 add hl, bc ld [hl], a ; are we on the last channel? (noise sampling) ld a, [CurChannel] maskbits NUM_MUSIC_CHANS cp CHAN4 ret z ; update hi frequency from next param call GetMusicByte ld hl, Channel1FrequencyHi - Channel1 add hl, bc ld [hl], a ret ; e86c5 GetNoiseSample: ; e86c5 ; load ptr to sample header in NoiseSampleAddress ; are we on the last channel? ld a, [CurChannel] and NUM_MUSIC_CHANS +- 1 cp CHAN4 ; ret if not ret nz ; update note duration ld a, [CurMusicByte] and $f call SetNoteDuration ; check current channel ld a, [CurChannel] bit 2, a ; are we in a sfx channel? jr nz, .sfx ld hl, Channel8Flags bit SOUND_CHANNEL_ON, [hl] ; is ch8 on? (noise) ret nz ld a, [MusicNoiseSampleSet] jr .next .sfx ld a, [SFXNoiseSampleSet] .next ; load noise sample set id into de ld e, a ld d, 0 ; load ptr to noise sample set in hl ld hl, Drumkits add hl, de add hl, de ld a, [hli] ld h, [hl] ld l, a ; get pitch ld a, [CurMusicByte] swap a ; non-rest note? and $f ret z ; use 'pitch' to seek noise sample set ld e, a ld d, 0 add hl, de add hl, de ; load sample pointer into NoiseSampleAddress ld a, [hli] ld [NoiseSampleAddress], a ld a, [hl] ld [NoiseSampleAddress + 1], a ; clear ???? xor a ld [wNoiseSampleDelay], a ret ; e870f ParseMusicCommand: ; e870f ; reload command ld a, [CurMusicByte] ; get command # sub $d0 ; first command ld e, a ld d, 0 ; seek command pointer ld hl, MusicCommands add hl, de add hl, de ; jump to the new pointer ld a, [hli] ld h, [hl] ld l, a jp hl ; e8720 MusicCommands: ; e8720 ; entries correspond to macros/sound.asm enumeration dw Music_Octave8 ; octave 8 dw Music_Octave7 ; octave 7 dw Music_Octave6 ; octave 6 dw Music_Octave5 ; octave 5 dw Music_Octave4 ; octave 4 dw Music_Octave3 ; octave 3 dw Music_Octave2 ; octave 2 dw Music_Octave1 ; octave 1 dw Music_NoteType ; note length + intensity dw Music_ForceOctave ; set starting octave dw Music_Tempo ; tempo dw Music_DutyCycle ; duty cycle dw Music_Intensity ; intensity dw Music_SoundStatus ; update sound status dw Music_SoundDuty ; sfx duty dw Music_ToggleSFX ; sound on/off dw Music_SlidePitchTo ; pitch wheel dw Music_Vibrato ; vibrato dw MusicE2 ; unused dw Music_ToggleNoise ; music noise sampling dw Music_Panning ; force panning dw Music_Volume ; volume dw Music_Tone ; tone dw MusicE7 ; unused dw MusicE8 ; unused dw Music_TempoRelative ; global tempo dw Music_RestartChannel ; restart current channel from header dw Music_NewSong ; new song dw Music_SFXPriorityOn ; sfx priority on dw Music_SFXPriorityOff ; sfx priority off dw MusicEE ; unused dw Music_StereoPanning ; stereo panning dw Music_SFXToggleNoise ; sfx noise sampling dw MusicF1 ; nothing dw MusicF2 ; nothing dw MusicF3 ; nothing dw MusicF4 ; nothing dw MusicF5 ; nothing dw MusicF6 ; nothing dw MusicF7 ; nothing dw MusicF8 ; nothing dw MusicF9 ; unused dw Music_SetCondition ; setcondition dw Music_JumpIf ; jumpif dw Music_JumpChannel ; jump dw Music_LoopChannel ; loop dw Music_CallChannel ; call dw Music_EndChannel ; return ; e8780 MusicF1: ; e8780 MusicF2: ; e8780 MusicF3: ; e8780 MusicF4: ; e8780 MusicF5: ; e8780 MusicF6: ; e8780 MusicF7: ; e8780 MusicF8: ; e8780 ret ; e8781 Music_EndChannel: ; e8781 ; called when $ff is encountered w/ subroutine flag set ; end music stream ; return to caller of the subroutine ; reset subroutine flag ld hl, Channel1Flags - Channel1 add hl, bc res SOUND_SUBROUTINE, [hl] ; copy LastMusicAddress to MusicAddress ld hl, Channel1LastMusicAddress - Channel1 add hl, bc ld e, [hl] inc hl ld d, [hl] ld hl, Channel1MusicAddress - Channel1 add hl, bc ld [hl], e inc hl ld [hl], d ret ; e8796 Music_CallChannel: ; e8796 ; call music stream (subroutine) ; parameters: ll hh ; pointer to subroutine ; get pointer from next 2 bytes call GetMusicByte ld e, a call GetMusicByte ld d, a push de ; copy MusicAddress to LastMusicAddress ld hl, Channel1MusicAddress - Channel1 add hl, bc ld e, [hl] inc hl ld d, [hl] ld hl, Channel1LastMusicAddress - Channel1 add hl, bc ld [hl], e inc hl ld [hl], d ; load pointer into MusicAddress pop de ld hl, Channel1MusicAddress - Channel1 add hl, bc ld [hl], e inc hl ld [hl], d ; set subroutine flag ld hl, Channel1Flags - Channel1 add hl, bc set SOUND_SUBROUTINE, [hl] ret ; e87bc Music_JumpChannel: ; e87bc ; jump ; parameters: ll hh ; pointer ; get pointer from next 2 bytes call GetMusicByte ld e, a call GetMusicByte ld d, a ld hl, Channel1MusicAddress - Channel1 add hl, bc ld [hl], e inc hl ld [hl], d ret ; e87cc Music_LoopChannel: ; e87cc ; loops xx - 1 times ; 00: infinite ; params: 3 ; xx ll hh ; xx : loop count ; ll hh : pointer ; get loop count call GetMusicByte ld hl, Channel1Flags - Channel1 add hl, bc bit SOUND_LOOPING, [hl] ; has the loop been initiated? jr nz, .checkloop and a ; loop counter 0 = infinite jr z, .loop ; initiate loop dec a set SOUND_LOOPING, [hl] ; set loop flag ld hl, Channel1LoopCount - Channel1 add hl, bc ld [hl], a ; store loop counter .checkloop ld hl, Channel1LoopCount - Channel1 add hl, bc ld a, [hl] and a ; are we done? jr z, .endloop dec [hl] .loop ; get pointer call GetMusicByte ld e, a call GetMusicByte ld d, a ; load new pointer into MusicAddress ld hl, Channel1MusicAddress - Channel1 add hl, bc ld [hl], e inc hl ld [hl], d ret .endloop ; reset loop flag ld hl, Channel1Flags - Channel1 add hl, bc res SOUND_LOOPING, [hl] ; skip to next command ld hl, Channel1MusicAddress - Channel1 add hl, bc ld e, [hl] inc hl ld d, [hl] inc de ; skip inc de ; pointer ld [hl], d dec hl ld [hl], e ret ; e880e Music_SetCondition: ; e880e ; set condition for a jump ; used with FB ; params: 1 ; xx ; condition ; set condition call GetMusicByte ld hl, Channel1Condition - Channel1 add hl, bc ld [hl], a ret ; e8817 Music_JumpIf: ; e8817 ; conditional jump ; used with FA ; params: 3 ; xx: condition ; ll hh: pointer ; check condition ; a = condition call GetMusicByte ; if existing condition matches, jump to new address ld hl, Channel1Condition - Channel1 add hl, bc cp [hl] jr z, .jump ; skip to next command ; get address ld hl, Channel1MusicAddress - Channel1 add hl, bc ld e, [hl] inc hl ld d, [hl] ; skip pointer inc de inc de ; update address ld [hl], d dec hl ld [hl], e ret .jump ; jump to the new address ; get pointer call GetMusicByte ld e, a call GetMusicByte ld d, a ; update pointer in MusicAddress ld hl, Channel1MusicAddress - Channel1 add hl, bc ld [hl], e inc hl ld [hl], d ret ; e883e MusicEE; e883e ; conditional jump ; checks a byte in ram corresponding to the current channel ; doesn't seem to be set by any commands ; params: 2 ; ll hh ; pointer ; if ????, jump ; get channel ld a, [CurChannel] maskbits NUM_MUSIC_CHANS ld e, a ld d, 0 ; hl = Channel1JumpCondition + channel id ld hl, Channel1JumpCondition add hl, de ; if set, jump ld a, [hl] and a jr nz, .jump ; skip to next command ; get address ld hl, Channel1MusicAddress - Channel1 add hl, bc ld e, [hl] inc hl ld d, [hl] ; skip pointer inc de inc de ; update address ld [hl], d dec hl ld [hl], e ret .jump ; reset jump flag ld [hl], 0 ; de = pointer call GetMusicByte ld e, a call GetMusicByte ld d, a ; update address ld hl, Channel1MusicAddress - Channel1 add hl, bc ld [hl], e inc hl ld [hl], d ret ; e886d MusicF9: ; e886d ; sets some flag ; seems to be unused ; params: 0 ld a, 1 ld [wc2b5], a ret ; e8873 MusicE2: ; e8873 ; seems to have been dummied out ; params: 1 call GetMusicByte ld hl, Channel1Field2c - Channel1 add hl, bc ld [hl], a ld hl, Channel1Flags2 - Channel1 add hl, bc set SOUND_UNKN_0B, [hl] ret ; e8882 Music_Vibrato: ; e8882 ; vibrato ; params: 2 ; 1: [xx] ; delay in frames ; 2: [yz] ; y: extent ; z: rate (# frames per cycle) ; set vibrato flag? ld hl, Channel1Flags2 - Channel1 add hl, bc set SOUND_VIBRATO, [hl] ; start at lower frequency (extent is positive) ld hl, Channel1Flags3 - Channel1 add hl, bc res SOUND_VIBRATO_DIR, [hl] ; get delay call GetMusicByte ; update delay ld hl, Channel1VibratoDelay - Channel1 add hl, bc ld [hl], a ; update delay count ld hl, Channel1VibratoDelayCount - Channel1 add hl, bc ld [hl], a ; update extent ; this is split into halves only to get added back together at the last second ; get extent/rate call GetMusicByte ld hl, Channel1VibratoExtent - Channel1 add hl, bc ld d, a ; get top nybble and $f0 swap a srl a ; halve ld e, a adc a, 0; round up swap a or e ld [hl], a ; update rate ld hl, Channel1VibratoRate - Channel1 add hl, bc ; get bottom nybble ld a, d and $f ld d, a swap a or d ld [hl], a ret ; e88bd Music_SlidePitchTo: ; e88bd ; set the target for pitch wheel ; params: 2 ; note duration ; target note call GetMusicByte ld [wCurNoteDuration], a call GetMusicByte ; pitch in e ld d, a and $f ld e, a ; octave in d ld a, d swap a and $f ld d, a call GetFrequency ld hl, Channel1PitchWheelTarget - Channel1 add hl, bc ld [hl], e ld hl, Channel1PitchWheelTarget + 1 - Channel1 add hl, bc ld [hl], d ld hl, Channel1Flags2 - Channel1 add hl, bc set SOUND_PITCH_WHEEL, [hl] ret ; e88e4 Music_Tone: ; e88e4 ; tone ; params: 1 (dw) ld hl, Channel1Flags2 - Channel1 add hl, bc set SOUND_CRY_PITCH, [hl] ld hl, Channel1CryPitch + 1 - Channel1 add hl, bc call GetMusicByte ld [hld], a call GetMusicByte ld [hl], a ret ; e88f7 MusicE7: ; e88f7 ; unused ; params: 1 ld hl, Channel1Flags2 - Channel1 add hl, bc set SOUND_UNKN_0E, [hl] call GetMusicByte ld hl, Channel1Field29 - Channel1 add hl, bc ld [hl], a ret ; e8906 Music_SoundDuty: ; e8906 ; sequence of 4 duty cycles to be looped ; params: 1 (4 2-bit duty cycle arguments) ld hl, Channel1Flags2 - Channel1 add hl, bc set SOUND_DUTY, [hl] ; duty cycle ; sound duty sequence call GetMusicByte rrca rrca ld hl, Channel1SFXDutyLoop - Channel1 add hl, bc ld [hl], a ; update duty cycle and $c0 ; only uses top 2 bits ld hl, Channel1DutyCycle - Channel1 add hl, bc ld [hl], a ret ; e891e MusicE8: ; e891e ; unused ; params: 1 ld hl, Channel1Flags2 - Channel1 add hl, bc set SOUND_UNKN_0D, [hl] call GetMusicByte ld hl, Channel1Field2a - Channel1 add hl, bc ld [hl], a ret ; e892d Music_ToggleSFX: ; e892d ; toggle something ; params: none ld hl, Channel1Flags - Channel1 add hl, bc bit SOUND_SFX, [hl] jr z, .on res SOUND_SFX, [hl] ret .on set SOUND_SFX, [hl] ret ; e893b Music_ToggleNoise: ; e893b ; toggle music noise sampling ; can't be used as a straight toggle since the param is not read from on->off ; params: ; noise on: 1 ; noise off: 0 ; check if noise sampling is on ld hl, Channel1Flags - Channel1 add hl, bc bit SOUND_NOISE, [hl] jr z, .on ; turn noise sampling off res SOUND_NOISE, [hl] ret .on ; turn noise sampling on set SOUND_NOISE, [hl] call GetMusicByte ld [MusicNoiseSampleSet], a ret ; e894f Music_SFXToggleNoise: ; e894f ; toggle sfx noise sampling ; params: ; on: 1 ; off: 0 ; check if noise sampling is on ld hl, Channel1Flags - Channel1 add hl, bc bit SOUND_NOISE, [hl] jr z, .on ; turn noise sampling off res SOUND_NOISE, [hl] ret .on ; turn noise sampling on set SOUND_NOISE, [hl] call GetMusicByte ld [SFXNoiseSampleSet], a ret ; e8963 Music_NoteType: ; e8963 ; note length ; # frames per 16th note ; intensity: see Music_Intensity ; params: 2 ; note length call GetMusicByte ld hl, Channel1NoteLength - Channel1 add hl, bc ld [hl], a ld a, [CurChannel] maskbits NUM_MUSIC_CHANS cp CHAN4 ret z ; intensity call Music_Intensity ret ; e8977 Music_SoundStatus: ; e8977 ; update sound status ; params: 1 call GetMusicByte ld [SoundInput], a ld hl, Channel1NoteFlags - Channel1 add hl, bc set NOTE_UNKN_3, [hl] ret ; e8984 Music_DutyCycle: ; e8984 ; duty cycle ; params: 1 call GetMusicByte rrca rrca and $c0 ld hl, Channel1DutyCycle - Channel1 add hl, bc ld [hl], a ret ; e8991 Music_Intensity: ; e8991 ; intensity ; params: 1 ; hi: pressure ; lo: velocity call GetMusicByte ld hl, Channel1Intensity - Channel1 add hl, bc ld [hl], a ret ; e899a Music_Tempo: ; e899a ; global tempo ; params: 2 ; de: tempo call GetMusicByte ld d, a call GetMusicByte ld e, a call SetGlobalTempo ret ; e89a6 Music_Octave8: ; e89a6 Music_Octave7: ; e89a6 Music_Octave6: ; e89a6 Music_Octave5: ; e89a6 Music_Octave4: ; e89a6 Music_Octave3: ; e89a6 Music_Octave2: ; e89a6 Music_Octave1: ; e89a6 ; set octave based on lo nybble of the command ld hl, Channel1Octave - Channel1 add hl, bc ld a, [CurMusicByte] and 7 ld [hl], a ret ; e89b1 Music_ForceOctave: ; e89b1 ; set starting octave ; this forces all notes up by the starting octave ; params: 1 call GetMusicByte ld hl, Channel1PitchOffset - Channel1 add hl, bc ld [hl], a ret ; e89ba Music_StereoPanning: ; e89ba ; stereo panning ; params: 1 ; stereo on? ld a, [Options] bit STEREO, a jr nz, Music_Panning ; skip param call GetMusicByte ret ; e89c5 Music_Panning: ; e89c5 ; force panning ; params: 1 call SetLRTracks call GetMusicByte ld hl, Channel1Tracks - Channel1 add hl, bc and [hl] ld [hl], a ret ; e89d2 Music_Volume: ; e89d2 ; set volume ; params: 1 ; see Volume ; read param even if it's not used call GetMusicByte ; is the song fading? ld a, [MusicFade] and a ret nz ; reload param ld a, [CurMusicByte] ; set volume ld [Volume], a ret ; e89e1 Music_TempoRelative: ; e89e1 ; set global tempo to current channel tempo +- param ; params: 1 signed call GetMusicByte ld e, a ; check sign cp $80 jr nc, .negative ;positive ld d, 0 jr .ok .negative ld d, -1 .ok ld hl, Channel1Tempo - Channel1 add hl, bc ld a, [hli] ld h, [hl] ld l, a add hl, de ld e, l ld d, h call SetGlobalTempo ret ; e89fd Music_SFXPriorityOn: ; e89fd ; turn sfx priority on ; params: none ld a, 1 ld [SFXPriority], a ret ; e8a03 Music_SFXPriorityOff: ; e8a03 ; turn sfx priority off ; params: none xor a ld [SFXPriority], a ret ; e8a08 Music_RestartChannel: ; e8a08 ; restart current channel from channel header (same bank) ; params: 2 (5) ; ll hh: pointer to new channel header ; header format: 0x yy zz ; x: channel # (0-3) ; zzyy: pointer to new music data ; update music id ld hl, Channel1MusicID - Channel1 add hl, bc ld a, [hli] ld [MusicID], a ld a, [hl] ld [MusicID + 1], a ; update music bank ld hl, Channel1MusicBank - Channel1 add hl, bc ld a, [hl] ld [MusicBank], a ; get pointer to new channel header call GetMusicByte ld l, a call GetMusicByte ld h, a ld e, [hl] inc hl ld d, [hl] push bc ; save current channel call LoadChannel call StartChannel pop bc ; restore current channel ret ; e8a30 Music_NewSong: ; e8a30 ; new song ; params: 2 ; de: song id call GetMusicByte ld e, a call GetMusicByte ld d, a push bc call _PlayMusic pop bc ret ; e8a3e GetMusicByte: ; e8a3e ; returns byte from current address in a ; advances to next byte in music data ; input: bc = start of current channel push hl push de ; load address into de ld hl, Channel1MusicAddress - Channel1 add hl, bc ld a, [hli] ld e, a ld d, [hl] ; load bank into a ld hl, Channel1MusicBank - Channel1 add hl, bc ld a, [hl] ; get byte call _LoadMusicByte ; load data into CurMusicByte inc de ; advance to next byte for next time this is called ; update channeldata address ld hl, Channel1MusicAddress - Channel1 add hl, bc ld a, e ld [hli], a ld [hl], d ; cleanup pop de pop hl ; store channeldata in a ld a, [CurMusicByte] ret ; e8a5d GetFrequency: ; e8a5d ; generate frequency ; input: ; d: octave ; e: pitch ; output: ; de: frequency ; get octave ; get starting octave ld hl, Channel1PitchOffset - Channel1 add hl, bc ld a, [hl] swap a ; hi nybble and $f ; add current octave add d push af ; we'll use this later ; get starting octave ld hl, Channel1PitchOffset - Channel1 add hl, bc ld a, [hl] and $f ; lo nybble ld l, a ; ok ld d, 0 ld h, d add hl, de ; add current pitch add hl, hl ; skip 2 bytes for each ld de, FrequencyTable add hl, de ld e, [hl] inc hl ld d, [hl] ; get our octave pop af ; shift right by [7 - octave] bits .loop ; [7 - octave] loops cp $7 jr nc, .ok ; sra de sra d rr e inc a jr .loop .ok ld a, d and $7 ; top 3 bits for frequency (11 total) ld d, a ret ; e8a8d SetNoteDuration: ; e8a8d ; input: a = note duration in 16ths ; store delay units in de inc a ld e, a ld d, 0 ; store NoteLength in a ld hl, Channel1NoteLength - Channel1 add hl, bc ld a, [hl] ; multiply NoteLength by delay units ld l, 0 ; just multiply call .Multiply ld a, l ; low ; store Tempo in de ld hl, Channel1Tempo - Channel1 add hl, bc ld e, [hl] inc hl ld d, [hl] ; add ???? to the next result ld hl, Channel1Field16 - Channel1 add hl, bc ld l, [hl] ; multiply Tempo by last result (NoteLength * LOW(delay)) call .Multiply ; copy result to de ld e, l ld d, h ; store result in ???? ld hl, Channel1Field16 - Channel1 add hl, bc ld [hl], e ; store result in NoteDuration ld hl, Channel1NoteDuration - Channel1 add hl, bc ld [hl], d ret ; e8ab8 .Multiply: ; e8ab8 ; multiplies a and de ; adds the result to l ; stores the result in hl ld h, 0 .loop ; halve a srl a ; is there a remainder? jr nc, .skip ; add it to the result add hl, de .skip ; add de, de sla e rl d ; are we done? and a jr nz, .loop ret ; e8ac7 SetGlobalTempo: ; e8ac7 push bc ; save current channel ; are we dealing with music or sfx? ld a, [CurChannel] cp CHAN5 jr nc, .sfxchannels ld bc, Channel1 call Tempo ld bc, Channel2 call Tempo ld bc, Channel3 call Tempo ld bc, Channel4 call Tempo jr .end .sfxchannels ld bc, Channel5 call Tempo ld bc, Channel6 call Tempo ld bc, Channel7 call Tempo ld bc, Channel8 call Tempo .end pop bc ; restore current channel ret ; e8b03 Tempo: ; e8b03 ; input: ; de: note length ; update Tempo ld hl, Channel1Tempo - Channel1 add hl, bc ld [hl], e inc hl ld [hl], d ; clear ???? xor a ld hl, Channel1Field16 - Channel1 add hl, bc ld [hl], a ret ; e8b11 StartChannel: ; e8b11 call SetLRTracks ld hl, Channel1Flags - Channel1 add hl, bc set SOUND_CHANNEL_ON, [hl] ; turn channel on ret ; e8b1b SetLRTracks: ; e8b1b ; set tracks for a the current channel to default ; seems to be redundant since this is overwritten by stereo data later push de ; store current channel in de ld a, [CurChannel] maskbits NUM_MUSIC_CHANS ld e, a ld d, 0 ; get this channel's lr tracks call GetLRTracks add hl, de ; de = channel 0-3 ld a, [hl] ; load lr tracks into Tracks ld hl, Channel1Tracks - Channel1 add hl, bc ld [hl], a pop de ret ; e8b30 _PlayMusic:: ; e8b30 ; load music call MusicOff ld hl, MusicID ld [hl], e ; song number inc hl ld [hl], d ; (always 0) ld hl, Music add hl, de ; three add hl, de ; byte add hl, de ; pointer ld a, [hli] ld [MusicBank], a ld e, [hl] inc hl ld d, [hl] ; music header address call LoadMusicByte ; store first byte of music header in a rlca rlca maskbits NUM_MUSIC_CHANS inc a .loop ; start playing channels push af call LoadChannel call StartChannel pop af dec a jr nz, .loop xor a ld [wc2b5], a ld [Channel1JumpCondition], a ld [Channel2JumpCondition], a ld [Channel3JumpCondition], a ld [Channel4JumpCondition], a ld [NoiseSampleAddress], a ld [NoiseSampleAddress + 1], a ld [wNoiseSampleDelay], a ld [MusicNoiseSampleSet], a call MusicOn ret ; e8b79 _PlayCry:: ; e8b79 ; Play cry de using parameters: ; CryPitch ; CryLength call MusicOff ; Overload the music id with the cry id ld hl, MusicID ld [hl], e inc hl ld [hl], d ; 3-byte pointers (bank, address) ld hl, Cries add hl, de add hl, de add hl, de ld a, [hli] ld [MusicBank], a ld e, [hl] inc hl ld d, [hl] ; Read the cry's sound header call LoadMusicByte ; Top 2 bits contain the number of channels rlca rlca maskbits NUM_MUSIC_CHANS ; For each channel: inc a .loop push af call LoadChannel ld hl, Channel1Flags - Channel1 add hl, bc set SOUND_REST, [hl] ld hl, Channel1Flags2 - Channel1 add hl, bc set SOUND_CRY_PITCH, [hl] ld hl, Channel1CryPitch - Channel1 add hl, bc ld a, [CryPitch] ld [hli], a ld a, [CryPitch + 1] ld [hl], a ; No tempo for channel 4 ld a, [CurChannel] maskbits NUM_MUSIC_CHANS cp CHAN4 jr nc, .start ; Tempo is effectively length ld hl, Channel1Tempo - Channel1 add hl, bc ld a, [CryLength] ld [hli], a ld a, [CryLength+1] ld [hl], a .start call StartChannel ld a, [wStereoPanningMask] and a jr z, .next ; Stereo only: Play cry from the monster's side. ; This only applies in-battle. ld a, [Options] bit STEREO, a jr z, .next ; [Tracks] &= [CryTracks] ld hl, Channel1Tracks - Channel1 add hl, bc ld a, [hl] ld hl, CryTracks and [hl] ld hl, Channel1Tracks - Channel1 add hl, bc ld [hl], a .next pop af dec a jr nz, .loop ; Cries play at max volume, so we save the current volume for later. ld a, [LastVolume] and a jr nz, .end ld a, [Volume] ld [LastVolume], a ld a, MAX_VOLUME ld [Volume], a .end ld a, 1 ; stop playing music ld [SFXPriority], a call MusicOn ret ; e8c04 _PlaySFX:: ; e8c04 ; clear channels if they aren't already call MusicOff ld hl, Channel5Flags bit SOUND_CHANNEL_ON, [hl] ; ch5 on? jr z, .ch6 res SOUND_CHANNEL_ON, [hl] ; turn it off xor a ld [rNR11], a ; length/wavepattern = 0 ld a, $8 ld [rNR12], a ; envelope = 0 xor a ld [rNR13], a ; frequency lo = 0 ld a, $80 ld [rNR14], a ; restart sound (freq hi = 0) xor a ld [SoundInput], a ; global sound off ld [rNR10], a ; sweep = 0 .ch6 ld hl, Channel6Flags bit SOUND_CHANNEL_ON, [hl] jr z, .ch7 res SOUND_CHANNEL_ON, [hl] ; turn it off xor a ld [rNR21], a ; length/wavepattern = 0 ld a, $8 ld [rNR22], a ; envelope = 0 xor a ld [rNR23], a ; frequency lo = 0 ld a, $80 ld [rNR24], a ; restart sound (freq hi = 0) .ch7 ld hl, Channel7Flags bit SOUND_CHANNEL_ON, [hl] jr z, .ch8 res SOUND_CHANNEL_ON, [hl] ; turn it off xor a ld [rNR30], a ; sound mode #3 off ld [rNR31], a ; length/wavepattern = 0 ld a, $8 ld [rNR32], a ; envelope = 0 xor a ld [rNR33], a ; frequency lo = 0 ld a, $80 ld [rNR34], a ; restart sound (freq hi = 0) .ch8 ld hl, Channel8Flags bit SOUND_CHANNEL_ON, [hl] jr z, .chscleared res SOUND_CHANNEL_ON, [hl] ; turn it off xor a ld [rNR41], a ; length/wavepattern = 0 ld a, $8 ld [rNR42], a ; envelope = 0 xor a ld [rNR43], a ; frequency lo = 0 ld a, $80 ld [rNR44], a ; restart sound (freq hi = 0) xor a ld [NoiseSampleAddress], a ld [NoiseSampleAddress + 1], a .chscleared ; start reading sfx header for # chs ld hl, MusicID ld [hl], e inc hl ld [hl], d ld hl, SFX add hl, de ; three add hl, de ; byte add hl, de ; pointers ; get bank ld a, [hli] ld [MusicBank], a ; get address ld e, [hl] inc hl ld d, [hl] ; get # channels call LoadMusicByte rlca ; top 2 rlca ; bits maskbits NUM_MUSIC_CHANS inc a ; # channels -> # loops .startchannels push af call LoadChannel ; bc = current channel ld hl, Channel1Flags - Channel1 add hl, bc set SOUND_SFX, [hl] call StartChannel pop af dec a jr nz, .startchannels call MusicOn xor a ld [SFXPriority], a ret ; e8ca6 PlayStereoSFX:: ; e8ca6 ; play sfx de call MusicOff ; standard procedure if stereo's off ld a, [Options] bit STEREO, a jp z, _PlaySFX ; else, let's go ahead with this ld hl, MusicID ld [hl], e inc hl ld [hl], d ; get sfx ptr ld hl, SFX add hl, de add hl, de add hl, de ; bank ld a, [hli] ld [MusicBank], a ; address ld e, [hl] inc hl ld d, [hl] ; bit 2-3 call LoadMusicByte rlca rlca maskbits NUM_MUSIC_CHANS inc a .loop push af call LoadChannel ld hl, Channel1Flags - Channel1 add hl, bc set SOUND_SFX, [hl] push de ; get tracks for this channel ld a, [CurChannel] maskbits NUM_MUSIC_CHANS ld e, a ld d, 0 call GetLRTracks add hl, de ld a, [hl] ld hl, wStereoPanningMask and [hl] ld hl, Channel1Tracks - Channel1 add hl, bc ld [hl], a ld hl, Channel1Field30 - Channel1 add hl, bc ld [hl], a ld a, [CryTracks] cp 2 ; ch 1-2 jr c, .skip ; ch3-4 ld a, [wSFXDuration] ld hl, Channel1Field2e - Channel1 add hl, bc ld [hl], a ld hl, Channel1Field2f - Channel1 add hl, bc ld [hl], a ld hl, Channel1Flags2 - Channel1 add hl, bc set SOUND_UNKN_0F, [hl] .skip pop de ; turn channel on ld hl, Channel1Flags - Channel1 add hl, bc set SOUND_CHANNEL_ON, [hl] ; on ; done? pop af dec a jr nz, .loop ; we're done call MusicOn ret ; e8d1b LoadChannel: ; e8d1b ; prep channel for use ; input: ; de: ; get pointer to current channel call LoadMusicByte inc de and $7 ; bit 0-2 (current channel) ld [CurChannel], a ld c, a ld b, 0 ld hl, ChannelPointers add hl, bc add hl, bc ld c, [hl] inc hl ld b, [hl] ; bc = channel pointer ld hl, Channel1Flags - Channel1 add hl, bc res SOUND_CHANNEL_ON, [hl] ; channel off call ChannelInit ; load music pointer ld hl, Channel1MusicAddress - Channel1 add hl, bc call LoadMusicByte ld [hli], a inc de call LoadMusicByte ld [hl], a inc de ; load music id ld hl, Channel1MusicID - Channel1 add hl, bc ld a, [MusicID] ld [hli], a ld a, [MusicID + 1] ld [hl], a ; load music bank ld hl, Channel1MusicBank - Channel1 add hl, bc ld a, [MusicBank] ld [hl], a ret ; e8d5b ChannelInit: ; e8d5b ; make sure channel is cleared ; set default tempo and note length in case nothing is loaded ; input: ; bc = channel struct pointer push de xor a ; get channel struct location and length ld hl, Channel1MusicID - Channel1 ; start add hl, bc ld e, Channel2 - Channel1 ; channel struct length ; clear channel .loop ld [hli], a dec e jr nz, .loop ; set tempo to default ($100) ld hl, Channel1Tempo - Channel1 add hl, bc xor a ld [hli], a inc a ld [hl], a ; set note length to default ($1) (fast) ld hl, Channel1NoteLength - Channel1 add hl, bc ld [hl], a pop de ret ; e8d76 LoadMusicByte:: ; e8d76 ; input: ; de = current music address ; output: ; a = CurMusicByte ld a, [MusicBank] call _LoadMusicByte ld a, [CurMusicByte] ret ; e8d80 INCLUDE "audio/notes.asm" INCLUDE "audio/wave_samples.asm" INCLUDE "audio/drumkits.asm" GetLRTracks: ; e8fc2 ; gets the default sound l/r channels ; stores mono/stereo table in hl ld a, [Options] bit STEREO, a ; made redundant, could have had a purpose in gold jr nz, .stereo ld hl, MonoTracks ret .stereo ld hl, StereoTracks ret ; e8fd1 MonoTracks: ; e8fd1 ; bit corresponds to track # ; hi: left channel ; lo: right channel db $11, $22, $44, $88 ; e8fd5 StereoTracks: ; e8fd5 ; made redundant ; seems to be modified on a per-song basis db $11, $22, $44, $88 ; e8fd9 ChannelPointers: ; e8fd9 ; music channels dw Channel1 dw Channel2 dw Channel3 dw Channel4 ; sfx channels dw Channel5 dw Channel6 dw Channel7 dw Channel8 ; e8fe9 ClearChannels:: ; e8fe9 ; runs ClearChannel for all 4 channels ; doesn't seem to be used, but functionally identical to MapSetup_Sound_Off ld hl, rNR50 xor a ld [hli], a ld [hli], a ld a, $80 ld [hli], a ld hl, rNR10 ld e, NUM_MUSIC_CHANS .loop call ClearChannel dec e jr nz, .loop ret ; e8ffe ClearChannel: ; e8ffe ; input: hl = beginning hw sound register (rNR10, rNR20, rNR30, rNR40) ; output: 00 00 80 00 80 ; sound channel 1 2 3 4 xor a ld [hli], a ; rNR10, rNR20, rNR30, rNR40 ; sweep = 0 ld [hli], a ; rNR11, rNR21, rNR31, rNR41 ; length/wavepattern = 0 ld a, $8 ld [hli], a ; rNR12, rNR22, rNR32, rNR42 ; envelope = 0 xor a ld [hli], a ; rNR13, rNR23, rNR33, rNR43 ; frequency lo = 0 ld a, $80 ld [hli], a ; rNR14, rNR24, rNR34, rNR44 ; restart sound (freq hi = 0) ret ; e900a PlayTrainerEncounterMusic:: ; e900a ; input: e = trainer type ; turn fade off xor a ld [MusicFade], a ; play nothing for one frame push de ld de, MUSIC_NONE call PlayMusic call DelayFrame ; play new song call MaxVolume pop de ld d, $00 ld hl, TrainerEncounterMusic add hl, de ld e, [hl] call PlayMusic ret ; e9027