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DevSound.asm
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; ================================================================
; DevSound - a Game Boy music system by DevEd
;
; Copyright (c) 2017 - 2018 DevEd
;
; Permission is hereby granted, free of charge, to any person obtaining
; a copy of this software and associated documentation files (the
; "Software"), to deal in the Software without restriction, including
; without limitation the rights to use, copy, modify, merge, publish,
; distribute, sublicense, and/or sell copies of the Software, and to
; permit persons to whom the Software is furnished to do so, subject to
; the following conditions:
;
; The above copyright notice and this permission notice shall be included
; in all copies or substantial portions of the Software.
;
; THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
; EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
; MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
; IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
; CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
; TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
; SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
; ================================================================
; Uncomment the following line to enable custom hooks.
; UseCustomHooks set 1
; Uncomment the following line if you want the DevSound player code to be in ROM0 instead of its own bank.
; Could be useful for multibank setups.
; TODO: Make some tweaks to song data format to allow for multiple banks
; UseROM0 set 1
; Uncomment the following line if you want to include song data elsewhere.
; Could be useful for multibank setups.
; TODO: Make some tweaks to song data format to allow for multiple banks
; DontIncludeSongData set 1
; Comment the following line to disable SFX support (via FX Hammer).
; Useful if you want to use your own sound effect system.
; (Note that DevSound may require some minor modifications if you
; want to use your own SFX system.)
UseFXHammer set 1
; Uncomment this to disable all time-consuming features
; This includes: wave buffer, PWM, random wave, zombie mode,
; wave volume scaling, channel volume
; WARNING! THIS IS CURRENTLY BROKEN. DO NOT USE!
; DemoSceneMode set 1
; Uncomment this to to disable wave volume scaling.
; PROS: Less CPU usage
; CONS: Less volume control for CH3
NoWaveVolumeScaling set 1
; Uncomment this to disable zombie mode (for compatibility
; with old emulators such as VBA).
; PROS: Less CPU usage
; Compatible with old emulators such as VBA
; CONS: Volume envelopes will sound "dirtier"
DisableZombieMode set 1
; Comment this line to enable Deflemask compatibility hacks.
DisableDeflehacks set 1
; Uncomment this line to enable FX Hammer disassembly support
UseFXHammerDisasm set 1
DevSound:
include "DevSound_Vars.asm"
include "DevSound_Consts.asm"
include "DevSound_Macros.asm"
SECTION "DevSound",romx,bank[1]
if !def(UseCustomHooks)
DevSound_JumpTable:
DS_Init: jp DevSound_Init
DS_Play: jp DevSound_Play
DS_Stop: jp DevSound_Stop
DS_Fade: jp DevSound_Fade
DS_ExternalCommand: jp DevSound_ExternalCommand
endc
; Driver thumbprint
db "DevSound GB music player by DevEd | email: [email protected]"
; ================================================================
; Init routine
; INPUT: a = ID of song to init
; ================================================================
DevSound_Init:
ld b,a ; Preserve song ID
xor a
ldh [rNR52],a ; disable sound
ld [PWMEnabled],a
ld [RandomizerEnabled],a
ld [WaveBufUpdateFlag],a
; init sound RAM area
ld de,InitVarsStart
ld c,DSVarsEnd-InitVarsStart
ld hl,DefaultRegTable
.initLoop
ld a,[hl+]
ld [de],a
inc de
dec c
jr nz,.initLoop
ld e,b ; Transfer song ID
; load default waveform
ld hl,DefaultWave
call LoadWave
; clear buffers
call ClearWaveBuffer
call ClearArpBuffer
; set up song pointers
ld hl,SongPointerTable
ld d,0
add hl,de
add hl,de
ld a,[hl+]
ld h,[hl]
ld l,a
ld a,[hl+]
ld [CH1Ptr],a
ld a,[hl+]
ld [CH1Ptr+1],a
ld a,[hl+]
ld [CH2Ptr],a
ld a,[hl+]
ld [CH2Ptr+1],a
ld a,[hl+]
ld [CH3Ptr],a
ld a,[hl+]
ld [CH3Ptr+1],a
ld a,[hl+]
ld [CH4Ptr],a
ld a,[hl+]
ld [CH4Ptr+1],a
ld hl,DummyChannel
ld a,[hl+]
ld h,[hl]
ld l,a
ld a,[hl+]
ld [CH1RetPtr],a
ld [CH2RetPtr],a
ld [CH3RetPtr],a
ld [CH4RetPtr],a
ld a,[hl]
ld [CH1RetPtr+1],a
ld [CH2RetPtr+1],a
ld [CH3RetPtr+1],a
ld [CH4RetPtr+1],a
ld a,$11
ld [CH1Pan],a
ld [CH2Pan],a
ld [CH3Pan],a
ld [CH4Pan],a
ld a,15
ld [CH1ChanVol],a
ld [CH2ChanVol],a
ld [CH3ChanVol],a
ld [CH4ChanVol],a
; get tempo
ld hl,SongSpeedTable
add hl,de
add hl,de
ld a,[hl+]
dec a
ld [GlobalSpeed1],a
ld a,[hl]
dec a
ld [GlobalSpeed2],a
ld a,%10000000
ldh [rNR52],a
ld a,$FF
ldh [rNR51],a
ld a,7
ld [GlobalVolume],a
; if visualizer is enabled, init it too
if def(Visualizer)
if !def(DemoSceneMode) && !def(NoWaveVolumeScaling)
CopyBytes DefaultWave,VisualizerTempWave,16
endc
call VisualizerInit
endc
ret
; ================================================================
; External command processing routine
; INPUT: a = command ID
; bc = parameters
; ================================================================
DevSound_ExternalCommand:
cp (.commandTableEnd-.commandTable)/2
ret nc ; if command ID is out of bounds, exit
ld hl,.commandTable
add a
add l
ld l,a
jr nc,.nocarry
inc h
.nocarry
ld a,[hl+]
ld h,[hl]
ld l,a
jp hl
.commandTable
dw .dummy ; $00 - dummy
dw .setSpeed ; $01 - set speed
dw .muteChannel ; $02 - mute given sound channel (TODO)
.commandTableEnd
.setSpeed
ld a,b
ld [GlobalSpeed1],a
ld a,c
ld [GlobalSpeed2],a
; ret
.muteChannel ; TODO
; ld a,c
; and 3
.dummy
ret
; ================================================================
; Stop routine
; ================================================================
DevSound_Stop:
ld c,low(rNR52)
xor a
ld [c],a ; disable sound output (resets all sound regs)
set 7,a
ld [c],a ; enable sound output
dec c
or $ff
ld [c],a ; all sound channels to left+right speakers
dec c
and $77
ld [c],a ; VIN output off + master volume max
xor a
ld [CH1Enabled],a
ld [CH2Enabled],a
ld [CH3Enabled],a
ld [CH4Enabled],a
ld [SoundEnabled],a
; if visualizer is enabled, init it too (to make everything zero)
if def(Visualizer)
jp VisualizerInit
else
ret
endc
; ================================================================
; Fade routine
; Note: if planning to call both this and DS_Init, call this first.
; ================================================================
DevSound_Fade:
and 3
cp 3
ret z ; 3 is an invalid value, silently ignore it
inc a ; Increment...
set 2,a ; Mark this fade as the first
ld [FadeType],a
ld a,7
ld [FadeTimer],a
ret
; ================================================================
; Play routine
; ================================================================
DevSound_Play:
; Since this routine is called during an interrupt (which may
; happen in the middle of a routine), preserve all register
; values just to be safe.
; Other registers are saved at `.doUpdate`.
push af
ld a,[SoundEnabled]
and a
jr nz,.doUpdate ; if sound is enabled, jump ahead
pop af
ret
.doUpdate
push bc
push de
push hl
; do stuff with sync tick
ld a,[SyncTick]
and a
jr z,.getSongTimer
dec a
ld [SyncTick],a
.getSongTimer
ld a,[GlobalTimer] ; get global timer
and a ; is GlobalTimer non-zero?
jr nz,.noupdate ; if yes, don't update
ld a,[TickCount] ; get current tick count
xor 1 ; toggle between 0 and 1
ld [TickCount],a ; store it in RAM
jr nz,.odd ; if a is 1, jump
.even
ld a,[GlobalSpeed1]
jr .setTimer
.odd
ld a,[GlobalSpeed2]
.setTimer
ld [GlobalTimer],a ; store timer value
jr UpdateCH1 ; continue ahead
.noupdate
dec a ; subtract 1 from timer
ld [GlobalTimer],a ; store timer value
jp DoneUpdating ; done
; ================================================================
UpdateCH1:
ld a,[CH1Enabled]
and a
jp z,UpdateCH2 ; if channel is disabled, skip to UpdateCH2
ld a,[CH1Tick]
and a
jr z,.continue ; if channel tick = 0, then jump ahead
dec a ; otherwise...
ld [CH1Tick],a ; decrement channel tick...
jp UpdateCH2 ; ...and skip to UpdateCH2.
.continue
ld hl,CH1Ptr ; get pointer
ld a,[hl+]
ld h,[hl]
ld l,a
CH1_CheckByte:
ld a,[hl+] ; get byte
cp $ff ; if $ff...
jr z,.endChannel
cp $c9 ; if $c9...
jr z,.retSection
cp release ; if release
jp z,.release
cp ___ ; if null note...
jr z,.nullnote
bit 7,a ; if command...
jp nz,.getCommand
; if we have a note...
.getNote
ld [CH1NoteBackup],a ; set note
ld a,[hl+] ; get note length
dec a ; subtract 1
ld [CH1Tick],a ; set channel tick
ld a,l ; store back current pos
ld [CH1Ptr],a
ld a,h
ld [CH1Ptr+1],a
ld a,[CH1PortaType]
dec a ; if toneporta, don't reset everything
jr z,.noreset
xor a
ld [CH1ArpPos],a ; reset arp position
inc a
ld [CH1VibPos],a ; reset vibrato position
ld hl,CH1VibPtr
ld a,[hl+]
ld h,[hl]
ld l,a
ld a,[hl] ; get vibrato delay
ld [CH1VibDelay],a ; set delay
xor a
ld hl,CH1Reset
bit 0,[hl]
jr nz,.noreset_checkvol
ld [CH1PulsePos],a
.noreset_checkvol
bit 1,[hl]
jr nz,.noreset
ld [CH1VolPos],a
ld [CH1VolLoop],a
.noreset
ld a,[CH1NoteCount]
inc a
ld [CH1NoteCount],a
ld b,a
; check if instrument mode is 1 (alternating)
ld a,[CH1InsMode]
and a
jr z,.noInstrumentChange
ld a,b
rra
jr nc,.notodd
ld a,[CH1Ins1]
jr .odd
.notodd
ld a,[CH1Ins2]
.odd
call CH1_SetInstrument
.noInstrumentChange
ld hl,CH1Reset
set 7,[hl] ; signal the start of note for pitch bend
jp UpdateCH2
.endChannel
xor a
ld [CH1Enabled],a
jp UpdateCH2
.retSection
ld hl,CH1RetPtr
ld a,[hl+]
ld [CH1Ptr],a
ld a,[hl]
ld [CH1Ptr+1],a
jp UpdateCH1
.nullnote
ld a,[hl+]
dec a
ld [CH1Tick],a ; set tick
ld a,l ; store back current pos
ld [CH1Ptr],a
ld a,h
ld [CH1Ptr+1],a
jp UpdateCH2
.release
; follows FamiTracker's behavior except vibrato table which will not be affected
ld a,[hl+]
dec a
ld [CH1Tick],a ; set tick
ld a,l ; store back current pos
ld [CH1Ptr],a
ld a,h
ld [CH1Ptr+1],a
ld hl,CH1VolPtr
ld bc,CH1VolPos
call SkipLoopPoint
ld hl,CH1ArpPtr
ld bc,CH1ArpPos
call SkipLoopPoint
ld hl,CH1PulsePtr
ld bc,CH1PulsePos
call SkipLoopPoint
jp UpdateCH2
.getCommand
cp DummyCommand
jp nc, CH1_CheckByte
; Not needed because function performs "add a" which discards bit 7
; sub $80 ; subtract 128 from command value
call JumpTableBelow
dw .setInstrument
dw .setLoopPoint
dw .gotoLoopPoint
dw .callSection
dw .setChannelPtr
dw .pitchBendUp
dw .pitchBendDown
dw .setSweep
dw .setPan
dw .setSpeed
dw .setInsAlternate
dw CH1_CheckByte ;.randomizeWave
dw .combineWaves
dw .enablePWM
dw .enableRandomizer
dw CH1_CheckByte ;.disableAutoWave
dw .arp
dw .toneporta
dw .chanvol
dw .setSyncTick
.setInstrument
ld a,[hl+] ; get ID of instrument to switch to
push hl ; preserve HL
call CH1_SetInstrument
xor a
ld [CH1InsMode],a ; reset instrument mode
pop hl ; restore HL
jp CH1_CheckByte
.setLoopPoint
ld a,l
ld [CH1LoopPtr],a
ld a,h
ld [CH1LoopPtr+1],a
jp CH1_CheckByte
.gotoLoopPoint
ld hl,CH1LoopPtr ; get loop pointer
ld a,[hl+]
ld [CH1Ptr],a
ld a,[hl]
ld [CH1Ptr+1],a
jp UpdateCH1
.callSection
ld a,[hl+]
ld [CH1Ptr],a
ld a,[hl+]
ld [CH1Ptr+1],a
ld a,l
ld [CH1RetPtr],a
ld a,h
ld [CH1RetPtr+1],a
jp UpdateCH1
.setChannelPtr
ld a,[hl+]
ld [CH1Ptr],a
ld a,[hl]
ld [CH1Ptr+1],a
jp UpdateCH1
.pitchBendUp
ld a,[hl+]
ld [CH1PortaSpeed],a
and a
jr z,.loadPortaType
ld a,2
jr .loadPortaType
.pitchBendDown
ld a,[hl+]
ld [CH1PortaSpeed],a
and a
jr z,.loadPortaType
ld a,3
jr .loadPortaType
.toneporta
ld a,[hl+]
ld [CH1PortaSpeed],a
and a
jr z,.loadPortaType
ld a,1
.loadPortaType
ld [CH1PortaType],a
jp CH1_CheckByte
.setSweep
ld a,[hl+]
ld [CH1Sweep],a
jp CH1_CheckByte
.setPan
ld a,[hl+]
ld [CH1Pan],a
jp CH1_CheckByte
.setSpeed
ld a,[hl+]
dec a
ld [GlobalSpeed1],a
ld a,[hl+]
dec a
ld [GlobalSpeed2],a
jp CH1_CheckByte
.setInsAlternate
ld a,[hl+]
ld [CH1Ins1],a
ld a,[hl+]
ld [CH1Ins2],a
ld a,1
ld [CH1InsMode],a
jp CH1_CheckByte
.combineWaves
ld a,l
add 4
ld l,a
jp nc,CH1_CheckByte
inc h
jp CH1_CheckByte
.enablePWM
inc hl
inc hl
jp CH1_CheckByte
.setSyncTick
ld a,[hl+]
ld [SyncTick],a
jp CH1_CheckByte
.enableRandomizer
inc hl
jp CH1_CheckByte
.arp
call DoArp
jp CH1_CheckByte
.chanvol
ld a,[hl+]
and $f
ld [CH1ChanVol],a
jp CH1_CheckByte
CH1_SetInstrument:
ld hl,InstrumentTable
ld e,a
ld d,0
add hl,de
add hl,de
ld a,[hl+]
ld h,[hl]
ld l,a
; no reset flag
ld a,[hl+]
and 3
ld [CH1Reset],a
ld b,a
; vol table
ld a,[hl+]
ld [CH1VolPtr],a
ld a,[hl+]
ld [CH1VolPtr+1],a
; arp table
ld a,[hl+]
ld [CH1ArpPtr],a
ld a,[hl+]
ld [CH1ArpPtr+1],a
; pulse table
ld a,[hl+]
ld [CH1PulsePtr],a
ld a,[hl+]
ld [CH1PulsePtr+1],a
; vib table
ld a,[hl+]
ld [CH1VibPtr],a
ld a,[hl+]
ld [CH1VibPtr+1],a
ld hl,CH1VibPtr
ld a,[hl+]
ld h,[hl]
ld l,a
ld a,[hl]
ld [CH1VibDelay],a
ret
; ================================================================
UpdateCH2:
ld a,[CH2Enabled]
and a
jp z,UpdateCH3
ld a,[CH2Tick]
and a
jr z,.continue
dec a
ld [CH2Tick],a
jp UpdateCH3
.continue
ld hl,CH2Ptr ; get pointer
ld a,[hl+]
ld h,[hl]
ld l,a
CH2_CheckByte:
ld a,[hl+] ; get byte
cp $ff
jp z,.endChannel
cp $c9
jp z,.retSection
cp release ; if release
jp z,.release
cp ___
jp z,.nullnote
bit 7,a ; check for command
jp nz,.getCommand
; if we have a note...
.getNote
ld [CH2NoteBackup],a
ld a,[hl+]
dec a
ld [CH2Tick],a
ld a,l ; store back current pos
ld [CH2Ptr],a
ld a,h
ld [CH2Ptr+1],a
ld a,[CH2PortaType]
dec a ; if toneporta, don't reset everything
jr z,.noreset
xor a
ld [CH2ArpPos],a
if(UseFXHammer)
ld a,[$cff0]
cp 3
jp z,.noupdate
endc
ldh [rNR22],a
.noupdate
inc a
ld [CH2VibPos],a
ld hl,CH2VibPtr
ld a,[hl+]
ld h,[hl]
ld l,a
ld a,[hl]
ld [CH2VibDelay],a
xor a
ld hl,CH2Reset
bit 0,[hl]
jr nz,.noreset_checkvol
ld [CH2PulsePos],a
.noreset_checkvol
bit 1,[hl]
jr nz,.noreset
ld [CH2VolPos],a
ld [CH2VolLoop],a
.noreset
ld a,[CH2NoteCount]
inc a
ld [CH2NoteCount],a
ld b,a
; check if instrument mode is 1 (alternating)
ld a,[CH2InsMode]
and a
jr z,.noInstrumentChange
ld a,b
rra
jr nc,.notodd
ld a,[CH2Ins1]
jr .odd
.notodd
ld a,[CH2Ins2]
.odd
call CH2_SetInstrument
.noInstrumentChange
ld hl,CH2Reset
set 7,[hl]
jp UpdateCH3
.endChannel
xor a
ld [CH2Enabled],a
jp UpdateCH3
.retSection
ld hl,CH2RetPtr
ld a,[hl+]
ld [CH2Ptr],a
ld a,[hl]
ld [CH2Ptr+1],a
jp UpdateCH2
.nullnote
ld a,[hl+]
dec a
ld [CH2Tick],a ; set tick
ld a,l ; store back current pos
ld [CH2Ptr],a
ld a,h
ld [CH2Ptr+1],a
jp UpdateCH3
.release
; follows FamiTracker's behavior except vibrato table which will not be affected
ld a,[hl+]
dec a
ld [CH2Tick],a ; set tick
ld a,l ; store back current pos
ld [CH2Ptr],a
ld a,h
ld [CH2Ptr+1],a
ld hl,CH2VolPtr
ld bc,CH2VolPos
call SkipLoopPoint
ld hl,CH2ArpPtr
ld bc,CH2ArpPos
call SkipLoopPoint
ld hl,CH2PulsePtr
ld bc,CH2PulsePos
call SkipLoopPoint
jp UpdateCH3
.getCommand
cp DummyCommand
jp nc,CH2_CheckByte
; Not needed because function performs "add a" which discards bit 7
; sub $80
call JumpTableBelow
dw .setInstrument
dw .setLoopPoint
dw .gotoLoopPoint
dw .callSection
dw .setChannelPtr
dw .pitchBendUp
dw .pitchBendDown
dw .setSweep
dw .setPan
dw .setSpeed
dw .setInsAlternate
dw CH2_CheckByte ;.randomizeWave
dw .combineWaves
dw .enablePWM
dw .enableRandomizer
dw CH2_CheckByte ;.disableAutoWave
dw .arp
dw .toneporta
dw .chanvol
dw .setSyncTick
.setInstrument
ld a,[hl+]
push hl
call CH2_SetInstrument
pop hl
xor a
ld [CH2InsMode],a
jp CH2_CheckByte
.setLoopPoint
ld a,l
ld [CH2LoopPtr],a
ld a,h
ld [CH2LoopPtr+1],a
jp CH2_CheckByte
.gotoLoopPoint
ld hl,CH2LoopPtr
ld a,[hl+]
ld [CH2Ptr],a
ld a,[hl]
ld [CH2Ptr+1],a
jp UpdateCH2
.callSection
ld a,[hl+]
ld [CH2Ptr],a
ld a,[hl+]
ld [CH2Ptr+1],a
ld a,l
ld [CH2RetPtr],a
ld a,h
ld [CH2RetPtr+1],a
jp UpdateCH2
.setChannelPtr
ld a,[hl+]
ld [CH2Ptr],a
ld a,[hl]
ld [CH2Ptr+1],a
jp UpdateCH2
.pitchBendUp
ld a,[hl+]
ld [CH2PortaSpeed],a
and a
jr z,.loadPortaType
ld a,2
jr .loadPortaType
.pitchBendDown
ld a,[hl+]
ld [CH2PortaSpeed],a
and a
jr z,.loadPortaType
ld a,3
jr .loadPortaType
.toneporta
ld a,[hl+]
ld [CH2PortaSpeed],a
and a
jr z,.loadPortaType
ld a,1
.loadPortaType
ld [CH2PortaType],a
jp CH2_CheckByte
.setSweep
.enableRandomizer
inc hl
jp CH2_CheckByte
.setPan
ld a,[hl+]
ld [CH2Pan],a
jp CH2_CheckByte
.setSpeed
ld a,[hl+]
dec a
ld [GlobalSpeed1],a
ld a,[hl+]
dec a
ld [GlobalSpeed2],a
jp CH2_CheckByte
.setInsAlternate
ld a,[hl+]
ld [CH2Ins1],a
ld a,[hl+]
ld [CH2Ins2],a
ld a,1
ld [CH2InsMode],a
jp CH2_CheckByte
.combineWaves
ld a,l
add 4
ld l,a
jp nc,CH2_CheckByte
inc h
jp CH2_CheckByte
.enablePWM
inc hl
inc hl
jp CH2_CheckByte
.arp
call DoArp
jp CH2_CheckByte
.chanvol
ld a,[hl+]
and $f
ld [CH2ChanVol],a
jp CH2_CheckByte
.setSyncTick
ld a,[hl+]
ld [SyncTick],a
jp CH2_CheckByte
CH2_SetInstrument:
ld hl,InstrumentTable
ld e,a
ld d,0
add hl,de
add hl,de
ld a,[hl+]
ld h,[hl]
ld l,a
; no reset flag
ld a,[hl+]
and 3
ld [CH2Reset],a
ld b,a
; vol table
ld a,[hl+]
ld [CH2VolPtr],a
ld a,[hl+]
ld [CH2VolPtr+1],a
; arp table
ld a,[hl+]
ld [CH2ArpPtr],a
ld a,[hl+]
ld [CH2ArpPtr+1],a
; pulse table
ld a,[hl+]
ld [CH2PulsePtr],a
ld a,[hl+]
ld [CH2PulsePtr+1],a
; vib table
ld a,[hl+]
ld [CH2VibPtr],a
ld a,[hl+]
ld [CH2VibPtr+1],a
ld hl,CH2VibPtr
ld a,[hl+]
ld h,[hl]
ld l,a
ld a,[hl]
ld [CH2VibDelay],a
ret
; ================================================================
UpdateCH3:
ld a,[CH3Enabled]
and a
jp z,UpdateCH4
ld a,[CH3Tick]
and a
jr z,.continue
dec a
ld [CH3Tick],a
jp UpdateCH4
.continue