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ninjadynamics/gist:af0b2e231122454a0980f5388f7351bd

Created January 1, 2024 23:04
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Famitone2 Bank Switching
Raw
gistfile1.txt
.segment "CODE"
.export _famitone_init,_famitone_update
.export _music_play,_music_stop,_music_pause
;from mmc3.h
.importzp _music_bank,_sfx_bank,_dpcm_bank
.importzp _mmc3_cpu_bank, _mmc3_register
.importzp _mmc3_last_register, _mmc3_last_cpu_bank
.importzp _active_data_bank,_active_data_bank_index
; - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
; Core Functionality
; - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
;void __fastcall__ famitone_init(void* music_data);
_famitone_init=FamiToneInit
;void __fastcall__ famitone_update(void);
_famitone_update=FamiToneUpdate
; - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
; - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
; Music
; - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
;void __fastcall__ music_play(unsigned char song);
_music_play=FamiToneMusicPlay
;void __fastcall__ music_stop(void);
_music_stop=FamiToneMusicStop
;void __fastcall__ music_pause(unsigned char pause);
_music_pause=FamiToneMusicPause
; - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
; - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
; Sound Effects
; - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
.if(FT_SFX_ENABLE)
.export _sfx_init
.export _sfx_play
;void __fastcall__ sfx_init(void* sounds_data);
_sfx_init=FamiToneSfxInit
;void __fastcall__ sfx_play(unsigned char sound,unsigned char channel);
_sfx_play:
and #$03
tax
lda @sfxPriority,x
tax
jsr popa
jmp FamiToneSfxPlay
@sfxPriority:
.byte FT_SFX_CH0,FT_SFX_CH1,FT_SFX_CH2,FT_SFX_CH3
.else
rts
.endif
; - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
; - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
; Samples
; - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
;void __fastcall__ sample_play(unsigned char sample);
.if(FT_DPCM_ENABLE)
.export _sample_play
;void __fastcall__ sample_play(unsigned char sample);
_sample_play=FamiToneSamplePlay
.else
_sample_play:
rts
.endif
; - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
; - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
; Bank switching macros
; - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
.macro switch_to_music_bank
.if(FT_BANKED_MUSIC)
lda #$06
sta _mmc3_register
lda _music_bank
sta _mmc3_cpu_bank
lda #($06 | A12_INVERSION)
sta $8000
lda _music_bank
sta $8001
.endif
.endmacro
.macro switch_to_SFX_bank
.if(FT_BANKED_SFX)
lda #$06
sta _mmc3_register
lda _sfx_bank
sta _mmc3_cpu_bank
lda #($06 | A12_INVERSION)
sta $8000
lda _sfx_bank
sta $8001
.endif
.endmacro
.macro switch_to_DPCM_bank
.if(FT_BANKED_DPCM)
lda #$06
sta _mmc3_register
lda _dpcm_bank
sta _mmc3_cpu_bank
lda #($06 | A12_INVERSION)
sta $8000
lda _dpcm_bank
sta $8001
.endif
.endmacro
.macro switch_to_active_data_bank
lda #($06 | A12_INVERSION)
sta $8000
ldy _active_data_bank_index
lda _active_data_bank,y
sta $8001
.endmacro
; - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
;======================================================================================================
;FamiTone2 v1.12 - Removed FT_PITCH_FIX
;======================================================================================================
;zero page variables
FT_TEMP_PTR = FT_TEMP ;word
FT_TEMP_PTR_L = FT_TEMP_PTR+0
FT_TEMP_PTR_H = FT_TEMP_PTR+1
FT_TEMP_VAR1 = FT_TEMP+2
;envelope structure offsets, 5 bytes per envelope, grouped by variable type
FT_ENVELOPES_ALL = 3+3+3+2 ;3 for the pulse and triangle channels, 2 for the noise channel
FT_ENV_STRUCT_SIZE = 5
FT_ENV_VALUE = FT_BASE_ADR+0*FT_ENVELOPES_ALL
FT_ENV_REPEAT = FT_BASE_ADR+1*FT_ENVELOPES_ALL
FT_ENV_ADR_L = FT_BASE_ADR+2*FT_ENVELOPES_ALL
FT_ENV_ADR_H = FT_BASE_ADR+3*FT_ENVELOPES_ALL
FT_ENV_PTR = FT_BASE_ADR+4*FT_ENVELOPES_ALL
;channel structure offsets, 7 bytes per channel
FT_CHANNELS_ALL = 5
FT_CHN_STRUCT_SIZE = 9
FT_CHN_PTR_L = FT_BASE_ADR+0*FT_CHANNELS_ALL
FT_CHN_PTR_H = FT_BASE_ADR+1*FT_CHANNELS_ALL
FT_CHN_NOTE = FT_BASE_ADR+2*FT_CHANNELS_ALL
FT_CHN_INSTRUMENT = FT_BASE_ADR+3*FT_CHANNELS_ALL
FT_CHN_REPEAT = FT_BASE_ADR+4*FT_CHANNELS_ALL
FT_CHN_RETURN_L = FT_BASE_ADR+5*FT_CHANNELS_ALL
FT_CHN_RETURN_H = FT_BASE_ADR+6*FT_CHANNELS_ALL
FT_CHN_REF_LEN = FT_BASE_ADR+7*FT_CHANNELS_ALL
FT_CHN_DUTY = FT_BASE_ADR+8*FT_CHANNELS_ALL
;variables and aliases
FT_ENVELOPES = FT_BASE_ADR
FT_CH1_ENVS = FT_ENVELOPES+0
FT_CH2_ENVS = FT_ENVELOPES+3
FT_CH3_ENVS = FT_ENVELOPES+6
FT_CH4_ENVS = FT_ENVELOPES+9
FT_CHANNELS = FT_ENVELOPES+FT_ENVELOPES_ALL*FT_ENV_STRUCT_SIZE
FT_CH1_VARS = FT_CHANNELS+0
FT_CH2_VARS = FT_CHANNELS+1
FT_CH3_VARS = FT_CHANNELS+2
FT_CH4_VARS = FT_CHANNELS+3
FT_CH5_VARS = FT_CHANNELS+4
FT_CH1_NOTE = FT_CH1_VARS+.lobyte(FT_CHN_NOTE)
FT_CH2_NOTE = FT_CH2_VARS+.lobyte(FT_CHN_NOTE)
FT_CH3_NOTE = FT_CH3_VARS+.lobyte(FT_CHN_NOTE)
FT_CH4_NOTE = FT_CH4_VARS+.lobyte(FT_CHN_NOTE)
FT_CH5_NOTE = FT_CH5_VARS+.lobyte(FT_CHN_NOTE)
FT_CH1_INSTRUMENT = FT_CH1_VARS+.lobyte(FT_CHN_INSTRUMENT)
FT_CH2_INSTRUMENT = FT_CH2_VARS+.lobyte(FT_CHN_INSTRUMENT)
FT_CH3_INSTRUMENT = FT_CH3_VARS+.lobyte(FT_CHN_INSTRUMENT)
FT_CH4_INSTRUMENT = FT_CH4_VARS+.lobyte(FT_CHN_INSTRUMENT)
FT_CH5_INSTRUMENT = FT_CH5_VARS+.lobyte(FT_CHN_INSTRUMENT)
FT_CH1_DUTY = FT_CH1_VARS+.lobyte(FT_CHN_DUTY)
FT_CH2_DUTY = FT_CH2_VARS+.lobyte(FT_CHN_DUTY)
FT_CH3_DUTY = FT_CH3_VARS+.lobyte(FT_CHN_DUTY)
FT_CH4_DUTY = FT_CH4_VARS+.lobyte(FT_CHN_DUTY)
FT_CH5_DUTY = FT_CH5_VARS+.lobyte(FT_CHN_DUTY)
FT_CH1_VOLUME = FT_CH1_ENVS+.lobyte(FT_ENV_VALUE)+0
FT_CH2_VOLUME = FT_CH2_ENVS+.lobyte(FT_ENV_VALUE)+0
FT_CH3_VOLUME = FT_CH3_ENVS+.lobyte(FT_ENV_VALUE)+0
FT_CH4_VOLUME = FT_CH4_ENVS+.lobyte(FT_ENV_VALUE)+0
FT_CH1_NOTE_OFF = FT_CH1_ENVS+.lobyte(FT_ENV_VALUE)+1
FT_CH2_NOTE_OFF = FT_CH2_ENVS+.lobyte(FT_ENV_VALUE)+1
FT_CH3_NOTE_OFF = FT_CH3_ENVS+.lobyte(FT_ENV_VALUE)+1
FT_CH4_NOTE_OFF = FT_CH4_ENVS+.lobyte(FT_ENV_VALUE)+1
FT_CH1_PITCH_OFF = FT_CH1_ENVS+.lobyte(FT_ENV_VALUE)+2
FT_CH2_PITCH_OFF = FT_CH2_ENVS+.lobyte(FT_ENV_VALUE)+2
FT_CH3_PITCH_OFF = FT_CH3_ENVS+.lobyte(FT_ENV_VALUE)+2
FT_VARS = FT_CHANNELS+FT_CHANNELS_ALL*FT_CHN_STRUCT_SIZE
FT_PAL_ADJUST = FT_VARS+0
FT_SONG_LIST_L = FT_VARS+1
FT_SONG_LIST_H = FT_VARS+2
FT_INSTRUMENT_L = FT_VARS+3
FT_INSTRUMENT_H = FT_VARS+4
FT_TEMPO_STEP_L = FT_VARS+5
FT_TEMPO_STEP_H = FT_VARS+6
FT_TEMPO_ACC_L = FT_VARS+7
FT_TEMPO_ACC_H = FT_VARS+8
FT_SONG_SPEED = FT_CH5_INSTRUMENT
FT_PULSE1_PREV = FT_CH3_DUTY
FT_PULSE2_PREV = FT_CH5_DUTY
FT_DPCM_LIST_L = FT_VARS+9
FT_DPCM_LIST_H = FT_VARS+10
FT_DPCM_EFFECT = FT_VARS+11
FT_OUT_BUF = FT_VARS+12 ;11 bytes
;sound effect stream variables, 2 bytes and 15 bytes per stream
;when sound effects are disabled, this memory is not used
FT_SFX_ADR_L = FT_VARS+23
FT_SFX_ADR_H = FT_VARS+24
FT_SFX_BASE_ADR = FT_VARS+25
FT_SFX_STRUCT_SIZE = 15
FT_SFX_REPEAT = FT_SFX_BASE_ADR+0
FT_SFX_PTR_L = FT_SFX_BASE_ADR+1
FT_SFX_PTR_H = FT_SFX_BASE_ADR+2
FT_SFX_OFF = FT_SFX_BASE_ADR+3
FT_SFX_BUF = FT_SFX_BASE_ADR+4 ;11 bytes
;aliases for sound effect channels to use in user calls
FT_SFX_CH0 = FT_SFX_STRUCT_SIZE*0
FT_SFX_CH1 = FT_SFX_STRUCT_SIZE*1
FT_SFX_CH2 = FT_SFX_STRUCT_SIZE*2
FT_SFX_CH3 = FT_SFX_STRUCT_SIZE*3
;aliases for the APU registers
APU_PL1_VOL = $4000
APU_PL1_SWEEP = $4001
APU_PL1_LO = $4002
APU_PL1_HI = $4003
APU_PL2_VOL = $4004
APU_PL2_SWEEP = $4005
APU_PL2_LO = $4006
APU_PL2_HI = $4007
APU_TRI_LINEAR = $4008
APU_TRI_LO = $400a
APU_TRI_HI = $400b
APU_NOISE_VOL = $400c
APU_NOISE_LO = $400e
APU_NOISE_HI = $400f
APU_DMC_FREQ = $4010
APU_DMC_RAW = $4011
APU_DMC_START = $4012
APU_DMC_LEN = $4013
APU_SND_CHN = $4015
;aliases for the APU registers in the output buffer
.if(!FT_SFX_ENABLE) ;if sound effects are disabled, write to the APU directly
FT_MR_PULSE1_V = APU_PL1_VOL
FT_MR_PULSE1_L = APU_PL1_LO
FT_MR_PULSE1_H = APU_PL1_HI
FT_MR_PULSE2_V = APU_PL2_VOL
FT_MR_PULSE2_L = APU_PL2_LO
FT_MR_PULSE2_H = APU_PL2_HI
FT_MR_TRI_V = APU_TRI_LINEAR
FT_MR_TRI_L = APU_TRI_LO
FT_MR_TRI_H = APU_TRI_HI
FT_MR_NOISE_V = APU_NOISE_VOL
FT_MR_NOISE_F = APU_NOISE_LO
.else ;otherwise write to the output buffer
FT_MR_PULSE1_V = FT_OUT_BUF
FT_MR_PULSE1_L = FT_OUT_BUF+1
FT_MR_PULSE1_H = FT_OUT_BUF+2
FT_MR_PULSE2_V = FT_OUT_BUF+3
FT_MR_PULSE2_L = FT_OUT_BUF+4
FT_MR_PULSE2_H = FT_OUT_BUF+5
FT_MR_TRI_V = FT_OUT_BUF+6
FT_MR_TRI_L = FT_OUT_BUF+7
FT_MR_TRI_H = FT_OUT_BUF+8
FT_MR_NOISE_V = FT_OUT_BUF+9
FT_MR_NOISE_F = FT_OUT_BUF+10
.endif
;------------------------------------------------------------------------------
; reset APU, initialize FamiTone
;------------------------------------------------------------------------------
FamiToneInit:
sta FT_SONG_LIST_L ;store music data pointer for further use
stx FT_SONG_LIST_H
sta <FT_TEMP_PTR_L
stx <FT_TEMP_PTR_H
@pal:
.if(FT_PAL_SUPPORT)
lda #0
.endif
.if(FT_NTSC_SUPPORT)
lda #64
.endif
sta FT_PAL_ADJUST
jsr FamiToneMusicStop ;initialize channels and envelopes
ldy #1
lda (FT_TEMP_PTR),y ;get instrument list address
sta FT_INSTRUMENT_L
iny
lda (FT_TEMP_PTR),y
sta FT_INSTRUMENT_H
iny
lda (FT_TEMP_PTR),y ;get sample list address
sta FT_DPCM_LIST_L
iny
lda (FT_TEMP_PTR),y
sta FT_DPCM_LIST_H
lda #$ff ;previous pulse period MSB, to not write it when not changed
sta FT_PULSE1_PREV
sta FT_PULSE2_PREV
lda #$0f ;enable channels, stop DMC
sta APU_SND_CHN
lda #$80 ;disable triangle length counter
sta APU_TRI_LINEAR
lda #$00 ;load noise length
sta APU_NOISE_HI
lda #$30 ;volumes to 0
sta APU_PL1_VOL
sta APU_PL2_VOL
sta APU_NOISE_VOL
lda #$08 ;no sweep
sta APU_PL1_SWEEP
sta APU_PL2_SWEEP
;jmp FamiToneMusicStop
;------------------------------------------------------------------------------
; stop music that is currently playing, if any
; in: none
;------------------------------------------------------------------------------
FamiToneMusicStop:
lda #0
sta FT_SONG_SPEED ;stop music, reset pause flag
sta FT_DPCM_EFFECT ;no DPCM effect playing
ldx #.lobyte(FT_CHANNELS) ;initialize channel structures
@set_channels:
lda #0
sta FT_CHN_REPEAT,x
sta FT_CHN_INSTRUMENT,x
sta FT_CHN_NOTE,x
sta FT_CHN_REF_LEN,x
lda #$30
sta FT_CHN_DUTY,x
inx ;next channel
cpx #.lobyte(FT_CHANNELS)+FT_CHANNELS_ALL
bne @set_channels
ldx #.lobyte(FT_ENVELOPES) ;initialize all envelopes to the dummy envelope
@set_envelopes:
lda #.lobyte (_FT2DummyEnvelope)
sta FT_ENV_ADR_L,x
lda #.hibyte(_FT2DummyEnvelope)
sta FT_ENV_ADR_H,x
lda #0
sta FT_ENV_REPEAT,x
sta FT_ENV_VALUE,x
inx
cpx #.lobyte(FT_ENVELOPES)+FT_ENVELOPES_ALL
bne @set_envelopes
jmp FamiToneSampleStop
;------------------------------------------------------------------------------
; play music
; in: A number of subsong
;------------------------------------------------------------------------------
FamiToneMusicPlay:
ldx FT_SONG_LIST_L
stx <FT_TEMP_PTR_L
ldx FT_SONG_LIST_H
stx <FT_TEMP_PTR_H
ldy #0
cmp (FT_TEMP_PTR),y ;check if there is such sub song
bcs @skip
asl a ;multiply song number by 14
sta <FT_TEMP_PTR_L ;use pointer LSB as temp variable
asl a
tax
asl a
adc <FT_TEMP_PTR_L
stx <FT_TEMP_PTR_L
adc <FT_TEMP_PTR_L
adc #5 ;add offset
tay
lda FT_SONG_LIST_L ;restore pointer LSB
sta <FT_TEMP_PTR_L
jsr FamiToneMusicStop ;stop music, initialize channels and envelopes
ldx #.lobyte(FT_CHANNELS) ;initialize channel structures
@set_channels:
lda (FT_TEMP_PTR),y ;read channel pointers
sta FT_CHN_PTR_L,x
iny
lda (FT_TEMP_PTR),y
sta FT_CHN_PTR_H,x
iny
lda #0
sta FT_CHN_REPEAT,x
sta FT_CHN_INSTRUMENT,x
sta FT_CHN_NOTE,x
sta FT_CHN_REF_LEN,x
lda #$30
sta FT_CHN_DUTY,x
inx ;next channel
cpx #.lobyte(FT_CHANNELS)+FT_CHANNELS_ALL
bne @set_channels
lda FT_PAL_ADJUST ;read tempo for PAL or NTSC
beq @pal
iny
iny
@pal:
lda (FT_TEMP_PTR),y ;read the tempo step
sta FT_TEMPO_STEP_L
iny
lda (FT_TEMP_PTR),y
sta FT_TEMPO_STEP_H
lda #0 ;reset tempo accumulator
sta FT_TEMPO_ACC_L
lda #6 ;default speed
sta FT_TEMPO_ACC_H
sta FT_SONG_SPEED ;apply default speed, this also enables music
@skip:
rts
;------------------------------------------------------------------------------
; pause and unpause current music
; in: A 0 or not 0 to play or pause
;------------------------------------------------------------------------------
FamiToneMusicPause:
tax ;set SZ flags for A
beq @unpause
@pause:
jsr FamiToneSampleStop
lda #0 ;mute sound
sta FT_CH1_VOLUME
sta FT_CH2_VOLUME
sta FT_CH3_VOLUME
sta FT_CH4_VOLUME
lda FT_SONG_SPEED ;set pause flag
ora #$80
bne @done
@unpause:
lda FT_SONG_SPEED ;reset pause flag
and #$7f
@done:
sta FT_SONG_SPEED
rts
;------------------------------------------------------------------------------
; update FamiTone state, should be called every NMI
; in: none
;------------------------------------------------------------------------------
FamiToneUpdate:
lda _mmc3_register
sta _mmc3_last_register
lda _mmc3_cpu_bank
sta _mmc3_last_cpu_bank
switch_to_music_bank
.if(FT_THREAD)
lda FT_TEMP_PTR_L
pha
lda FT_TEMP_PTR_H
pha
.endif
lda FT_SONG_SPEED ;speed 0 means that no music is playing currently
bmi @pause ;bit 7 set is the pause flag
bne @update
@pause:
jmp @update_sound
@update:
clc ;update frame counter that considers speed, tempo, and PAL/NTSC
lda FT_TEMPO_ACC_L
adc FT_TEMPO_STEP_L
sta FT_TEMPO_ACC_L
lda FT_TEMPO_ACC_H
adc FT_TEMPO_STEP_H
cmp FT_SONG_SPEED
bcs @update_row ;overflow, row update is needed
sta FT_TEMPO_ACC_H ;no row update, skip to the envelopes update
jmp @update_envelopes
@update_row:
sec
sbc FT_SONG_SPEED
sta FT_TEMPO_ACC_H
ldx #.lobyte(FT_CH1_VARS) ;process channel 1
jsr _FT2ChannelUpdate
bcc @no_new_note1
ldx #.lobyte(FT_CH1_ENVS)
lda FT_CH1_INSTRUMENT
jsr _FT2SetInstrument
sta FT_CH1_DUTY
@no_new_note1:
ldx #.lobyte(FT_CH2_VARS) ;process channel 2
jsr _FT2ChannelUpdate
bcc @no_new_note2
ldx #.lobyte(FT_CH2_ENVS)
lda FT_CH2_INSTRUMENT
jsr _FT2SetInstrument
sta FT_CH2_DUTY
@no_new_note2:
ldx #.lobyte(FT_CH3_VARS) ;process channel 3
jsr _FT2ChannelUpdate
bcc @no_new_note3
ldx #.lobyte(FT_CH3_ENVS)
lda FT_CH3_INSTRUMENT
jsr _FT2SetInstrument
@no_new_note3:
ldx #.lobyte(FT_CH4_VARS) ;process channel 4
jsr _FT2ChannelUpdate
bcc @no_new_note4
ldx #.lobyte(FT_CH4_ENVS)
lda FT_CH4_INSTRUMENT
jsr _FT2SetInstrument
sta FT_CH4_DUTY
@no_new_note4:
.if(FT_DPCM_ENABLE)
ldx #.lobyte(FT_CH5_VARS) ;process channel 5
jsr _FT2ChannelUpdate
bcc @no_new_note5
lda FT_CH5_NOTE
bne @play_sample
jsr FamiToneSampleStop
bne @no_new_note5 ;A is non-zero after FamiToneSampleStop
@play_sample:
jsr FamiToneSamplePlayM
@no_new_note5:
.endif
@update_envelopes:
ldx #.lobyte(FT_ENVELOPES) ;process 11 envelopes
@env_process:
lda FT_ENV_REPEAT,x ;check envelope repeat counter
beq @env_read ;if it is zero, process envelope
dec FT_ENV_REPEAT,x ;otherwise decrement the counter
bne @env_next
@env_read:
lda FT_ENV_ADR_L,x ;load envelope data address into temp
sta <FT_TEMP_PTR_L
lda FT_ENV_ADR_H,x
sta <FT_TEMP_PTR_H
ldy FT_ENV_PTR,x ;load envelope pointer
@env_read_value:
lda (FT_TEMP_PTR),y ;read a byte of the envelope data
bpl @env_special ;values below 128 used as a special code, loop or repeat
clc ;values above 128 are output value+192 (output values are signed -63..64)
adc #256-192
sta FT_ENV_VALUE,x ;store the output value
iny ;advance the pointer
bne @env_next_store_ptr ;bra
@env_special:
bne @env_set_repeat ;zero is the loop point, non-zero values used for the repeat counter
iny ;advance the pointer
lda (FT_TEMP_PTR),y ;read loop position
tay ;use loop position
jmp @env_read_value ;read next byte of the envelope
@env_set_repeat:
iny
sta FT_ENV_REPEAT,x ;store the repeat counter value
@env_next_store_ptr:
tya ;store the envelope pointer
sta FT_ENV_PTR,x
@env_next:
inx ;next envelope
cpx #.lobyte(FT_ENVELOPES)+FT_ENVELOPES_ALL
bne @env_process
@update_sound:
;convert envelope and channel output data into APU register values in the output buffer
lda FT_CH1_NOTE
beq @ch1cut
clc
adc FT_CH1_NOTE_OFF
tax
lda FT_CH1_PITCH_OFF
tay
adc _FT2NoteTableLSB,x
sta FT_MR_PULSE1_L
tya ;sign extension for the pitch offset
ora #$7f
bmi @ch1sign
lda #0
@ch1sign:
adc _FT2NoteTableMSB,x
.if(!FT_SFX_ENABLE)
cmp FT_PULSE1_PREV
beq @ch1prev
sta FT_PULSE1_PREV
.endif
sta FT_MR_PULSE1_H
@ch1prev:
lda FT_CH1_VOLUME
@ch1cut:
ora FT_CH1_DUTY
sta FT_MR_PULSE1_V
lda FT_CH2_NOTE
beq @ch2cut
clc
adc FT_CH2_NOTE_OFF
tax
lda FT_CH2_PITCH_OFF
tay
adc _FT2NoteTableLSB,x
sta FT_MR_PULSE2_L
tya
ora #$7f
bmi @ch2sign
lda #0
@ch2sign:
adc _FT2NoteTableMSB,x
.if(!FT_SFX_ENABLE)
cmp FT_PULSE2_PREV
beq @ch2prev
sta FT_PULSE2_PREV
.endif
sta FT_MR_PULSE2_H
@ch2prev:
lda FT_CH2_VOLUME
@ch2cut:
ora FT_CH2_DUTY
sta FT_MR_PULSE2_V
lda FT_CH3_NOTE
beq @ch3cut
clc
adc FT_CH3_NOTE_OFF
tax
lda FT_CH3_PITCH_OFF
tay
adc _FT2NoteTableLSB,x
sta FT_MR_TRI_L
tya
ora #$7f
bmi @ch3sign
lda #0
@ch3sign:
adc _FT2NoteTableMSB,x
sta FT_MR_TRI_H
lda FT_CH3_VOLUME
@ch3cut:
ora #$80
sta FT_MR_TRI_V
lda FT_CH4_NOTE
beq @ch4cut
clc
adc FT_CH4_NOTE_OFF
and #$0f
eor #$0f
sta <FT_TEMP_VAR1
lda FT_CH4_DUTY
asl a
and #$80
ora <FT_TEMP_VAR1
sta FT_MR_NOISE_F
lda FT_CH4_VOLUME
@ch4cut:
ora #$f0
sta FT_MR_NOISE_V
.if(FT_SFX_ENABLE)
switch_to_SFX_bank
;process all sound effect streams
.if FT_SFX_STREAMS>0
ldx #FT_SFX_CH0
jsr _FT2SfxUpdate
.endif
.if FT_SFX_STREAMS>1
ldx #FT_SFX_CH1
jsr _FT2SfxUpdate
.endif
.if FT_SFX_STREAMS>2
ldx #FT_SFX_CH2
jsr _FT2SfxUpdate
.endif
.if FT_SFX_STREAMS>3
ldx #FT_SFX_CH3
jsr _FT2SfxUpdate
.endif
;send data from the output buffer to the APU
lda FT_OUT_BUF ;pulse 1 volume
sta APU_PL1_VOL
lda FT_OUT_BUF+1 ;pulse 1 period LSB
sta APU_PL1_LO
lda FT_OUT_BUF+2 ;pulse 1 period MSB, only applied when changed
cmp FT_PULSE1_PREV
beq @no_pulse1_upd
sta FT_PULSE1_PREV
sta APU_PL1_HI
@no_pulse1_upd:
lda FT_OUT_BUF+3 ;pulse 2 volume
sta APU_PL2_VOL
lda FT_OUT_BUF+4 ;pulse 2 period LSB
sta APU_PL2_LO
lda FT_OUT_BUF+5 ;pulse 2 period MSB, only applied when changed
cmp FT_PULSE2_PREV
beq @no_pulse2_upd
sta FT_PULSE2_PREV
sta APU_PL2_HI
@no_pulse2_upd:
lda FT_OUT_BUF+6 ;triangle volume (plays or not)
sta APU_TRI_LINEAR
lda FT_OUT_BUF+7 ;triangle period LSB
sta APU_TRI_LO
lda FT_OUT_BUF+8 ;triangle period MSB
sta APU_TRI_HI
lda FT_OUT_BUF+9 ;noise volume
sta APU_NOISE_VOL
lda FT_OUT_BUF+10 ;noise period
sta APU_NOISE_LO
.endif
.if(FT_THREAD)
pla
sta FT_TEMP_PTR_H
pla
sta FT_TEMP_PTR_L
.endif
lda _mmc3_last_register
sta _mmc3_register
lda _mmc3_last_cpu_bank
sta _mmc3_cpu_bank
switch_to_active_data_bank
rts
;internal routine, sets up envelopes of a channel according to current instrument
;in X envelope group offset, A instrument number
_FT2SetInstrument:
asl a ;instrument number is pre multiplied by 4
tay
lda FT_INSTRUMENT_H
adc #0 ;use carry to extend range for 64 instruments
sta <FT_TEMP_PTR_H
lda FT_INSTRUMENT_L
sta <FT_TEMP_PTR_L
lda (FT_TEMP_PTR),y ;duty cycle
sta <FT_TEMP_VAR1
iny
lda (FT_TEMP_PTR),y ;instrument pointer LSB
sta FT_ENV_ADR_L,x
iny
lda (FT_TEMP_PTR),y ;instrument pointer MSB
iny
sta FT_ENV_ADR_H,x
inx ;next envelope
lda (FT_TEMP_PTR),y ;instrument pointer LSB
sta FT_ENV_ADR_L,x
iny
lda (FT_TEMP_PTR),y ;instrument pointer MSB
sta FT_ENV_ADR_H,x
lda #0
sta FT_ENV_REPEAT-1,x ;reset env1 repeat counter
sta FT_ENV_PTR-1,x ;reset env1 pointer
sta FT_ENV_REPEAT,x ;reset env2 repeat counter
sta FT_ENV_PTR,x ;reset env2 pointer
cpx #.lobyte(FT_CH4_ENVS) ;noise channel has only two envelopes
bcs @no_pitch
inx ;next envelope
iny
sta FT_ENV_REPEAT,x ;reset env3 repeat counter
sta FT_ENV_PTR,x ;reset env3 pointer
lda (FT_TEMP_PTR),y ;instrument pointer LSB
sta FT_ENV_ADR_L,x
iny
lda (FT_TEMP_PTR),y ;instrument pointer MSB
sta FT_ENV_ADR_H,x
@no_pitch:
lda <FT_TEMP_VAR1
rts
;internal routine, parses channel note data
_FT2ChannelUpdate:
lda FT_CHN_REPEAT,x ;check repeat counter
beq @no_repeat
dec FT_CHN_REPEAT,x ;decrease repeat counter
clc ;no new note
rts
@no_repeat:
lda FT_CHN_PTR_L,x ;load channel pointer into temp
sta <FT_TEMP_PTR_L
lda FT_CHN_PTR_H,x
sta <FT_TEMP_PTR_H
@no_repeat_r:
ldy #0
@read_byte:
lda (FT_TEMP_PTR),y ;read byte of the channel
inc <FT_TEMP_PTR_L ;advance pointer
bne @no_inc_ptr1
inc <FT_TEMP_PTR_H
@no_inc_ptr1:
ora #0
bmi @special_code ;bit 7 0=note 1=special code
lsr a ;bit 0 set means the note is followed by an empty row
bcc @no_empty_row
inc FT_CHN_REPEAT,x ;set repeat counter to 1
@no_empty_row:
sta FT_CHN_NOTE,x ;store note code
sec ;new note flag is set
bcs @done ;bra
@special_code:
and #$7f
lsr a
bcs @set_empty_rows
asl a
asl a
sta FT_CHN_INSTRUMENT,x ;store instrument number*4
bcc @read_byte ;bra
@set_empty_rows:
cmp #$3d
bcc @set_repeat
beq @set_speed
cmp #$3e
beq @set_loop
@set_reference:
clc ;remember return address+3
lda <FT_TEMP_PTR_L
adc #3
sta FT_CHN_RETURN_L,x
lda <FT_TEMP_PTR_H
adc #0
sta FT_CHN_RETURN_H,x
lda (FT_TEMP_PTR),y ;read length of the reference (how many rows)
sta FT_CHN_REF_LEN,x
iny
lda (FT_TEMP_PTR),y ;read 16-bit absolute address of the reference
sta <FT_TEMP_VAR1 ;remember in temp
iny
lda (FT_TEMP_PTR),y
sta <FT_TEMP_PTR_H
lda <FT_TEMP_VAR1
sta <FT_TEMP_PTR_L
ldy #0
jmp @read_byte
@set_speed:
lda (FT_TEMP_PTR),y
sta FT_SONG_SPEED
inc <FT_TEMP_PTR_L ;advance pointer after reading the speed value
bne @read_byte
inc <FT_TEMP_PTR_H
bne @read_byte ;bra
@set_loop:
lda (FT_TEMP_PTR),y
sta <FT_TEMP_VAR1
iny
lda (FT_TEMP_PTR),y
sta <FT_TEMP_PTR_H
lda <FT_TEMP_VAR1
sta <FT_TEMP_PTR_L
dey
jmp @read_byte
@set_repeat:
sta FT_CHN_REPEAT,x ;set up repeat counter, carry is clear, no new note
@done:
lda FT_CHN_REF_LEN,x ;check reference row counter
beq @no_ref ;if it is zero, there is no reference
dec FT_CHN_REF_LEN,x ;decrease row counter
bne @no_ref
lda FT_CHN_RETURN_L,x ;end of a reference, return to previous pointer
sta FT_CHN_PTR_L,x
lda FT_CHN_RETURN_H,x
sta FT_CHN_PTR_H,x
rts
@no_ref:
lda <FT_TEMP_PTR_L
sta FT_CHN_PTR_L,x
lda <FT_TEMP_PTR_H
sta FT_CHN_PTR_H,x
rts
;------------------------------------------------------------------------------
; stop DPCM sample if it plays
;------------------------------------------------------------------------------
FamiToneSampleStop:
lda #%00001111
sta APU_SND_CHN
rts
.if(FT_DPCM_ENABLE)
;------------------------------------------------------------------------------
; play DPCM sample, used by music player, could be used externally
; in: A is number of a sample, 1..63
;------------------------------------------------------------------------------
FamiToneSamplePlayM: ;for music (low priority)
ldx FT_DPCM_EFFECT
beq _FT2SamplePlay
tax
lda APU_SND_CHN
and #16
beq @not_busy
rts
@not_busy:
sta FT_DPCM_EFFECT
txa
jmp _FT2SamplePlay
;------------------------------------------------------------------------------
; play DPCM sample with higher priority, for sound effects
; in: A is number of a sample, 1..63
;------------------------------------------------------------------------------
FamiToneSamplePlay:
ldx #1
stx FT_DPCM_EFFECT
_FT2SamplePlay:
sta <FT_TEMP ;sample number*3, offset in the sample table
asl a
clc
adc <FT_TEMP
adc FT_DPCM_LIST_L
sta <FT_TEMP_PTR_L
lda #0
adc FT_DPCM_LIST_H
sta <FT_TEMP_PTR_H
lda #%00001111 ;stop DPCM
sta APU_SND_CHN
ldy #0
lda (FT_TEMP_PTR),y ;sample offset
sta APU_DMC_START
iny
lda (FT_TEMP_PTR),y ;sample length
sta APU_DMC_LEN
iny
lda (FT_TEMP_PTR),y ;pitch and loop
sta APU_DMC_FREQ
lda #32 ;reset DAC counter
sta APU_DMC_RAW
lda #%00011111 ;start DMC
sta APU_SND_CHN
rts
.endif
.if(FT_SFX_ENABLE)
;------------------------------------------------------------------------------
; init sound effects player, set pointer to data
; in: A,X is address of sound effects data
;------------------------------------------------------------------------------
FamiToneSfxInit:
sta <FT_TEMP_PTR_L
stx <FT_TEMP_PTR_H
ldy #0
@ntsc:
lda (FT_TEMP_PTR),y ;read and store pointer to the effects list
sta FT_SFX_ADR_L
iny
lda (FT_TEMP_PTR),y
sta FT_SFX_ADR_H
ldx #FT_SFX_CH0 ;init all the streams
@set_channels:
jsr _FT2SfxClearChannel
txa
clc
adc #FT_SFX_STRUCT_SIZE
tax
cpx #FT_SFX_STRUCT_SIZE*FT_SFX_STREAMS
bne @set_channels
rts
;internal routine, clears output buffer of a sound effect
;in: A is 0
; X is offset of sound effect stream
_FT2SfxClearChannel:
lda #0
sta FT_SFX_PTR_H,x ;this stops the effect
sta FT_SFX_REPEAT,x
sta FT_SFX_OFF,x
sta FT_SFX_BUF+6,x ;mute triangle
lda #$30
sta FT_SFX_BUF+0,x ;mute pulse1
sta FT_SFX_BUF+3,x ;mute pulse2
sta FT_SFX_BUF+9,x ;mute noise
rts
;------------------------------------------------------------------------------
; play sound effect
; in: A is a number of the sound effect 0..127
; X is offset of sound effect channel, should be FT_SFX_CH0..FT_SFX_CH3
;------------------------------------------------------------------------------
FamiToneSfxPlay:
asl a ;get offset in the effects list
tay
jsr _FT2SfxClearChannel ;stops the effect if it plays
lda FT_SFX_ADR_L
sta <FT_TEMP_PTR_L
lda FT_SFX_ADR_H
sta <FT_TEMP_PTR_H
lda (FT_TEMP_PTR),y ;read effect pointer from the table
sta FT_SFX_PTR_L,x ;store it
iny
lda (FT_TEMP_PTR),y
sta FT_SFX_PTR_H,x ;this write enables the effect
rts
;internal routine, update one sound effect stream
;in: X is offset of sound effect stream
_FT2SfxUpdate:
lda FT_SFX_REPEAT,x ;check if repeat counter is not zero
beq @no_repeat
dec FT_SFX_REPEAT,x ;decrement and return
bne @update_buf ;just mix with output buffer
@no_repeat:
lda FT_SFX_PTR_H,x ;check if MSB of the pointer is not zero
bne @sfx_active
rts ;return otherwise, no active effect
@sfx_active:
sta <FT_TEMP_PTR_H ;load effect pointer into temp
lda FT_SFX_PTR_L,x
sta <FT_TEMP_PTR_L
ldy FT_SFX_OFF,x
clc
@read_byte:
lda (FT_TEMP_PTR),y ;read byte of effect
bmi @get_data ;if bit 7 is set, it is a register write
beq @eof
iny
sta FT_SFX_REPEAT,x ;if bit 7 is reset, it is number of repeats
tya
sta FT_SFX_OFF,x
jmp @update_buf
@get_data:
iny
stx <FT_TEMP_VAR1 ;it is a register write
adc <FT_TEMP_VAR1 ;get offset in the effect output buffer
tax
lda (FT_TEMP_PTR),y ;read value
iny
sta FT_SFX_BUF-128,x ;store into output buffer
ldx <FT_TEMP_VAR1
jmp @read_byte ;and read next byte
@eof:
sta FT_SFX_PTR_H,x ;mark channel as inactive
@update_buf:
lda FT_OUT_BUF ;compare effect output buffer with main output buffer
and #$0f ;if volume of pulse 1 of effect is higher than that of the
sta <FT_TEMP_VAR1 ;main buffer, overwrite the main buffer value with the new one
lda FT_SFX_BUF+0,x
and #$0f
cmp <FT_TEMP_VAR1
bcc @no_pulse1
lda FT_SFX_BUF+0,x
sta FT_OUT_BUF+0
lda FT_SFX_BUF+1,x
sta FT_OUT_BUF+1
lda FT_SFX_BUF+2,x
sta FT_OUT_BUF+2
@no_pulse1:
lda FT_OUT_BUF+3 ;same for pulse 2
and #$0f
sta <FT_TEMP_VAR1
lda FT_SFX_BUF+3,x
and #$0f
cmp <FT_TEMP_VAR1
bcc @no_pulse2
lda FT_SFX_BUF+3,x
sta FT_OUT_BUF+3
lda FT_SFX_BUF+4,x
sta FT_OUT_BUF+4
lda FT_SFX_BUF+5,x
sta FT_OUT_BUF+5
@no_pulse2:
lda FT_SFX_BUF+6,x ;overwrite triangle of main output buffer if it is active
beq @no_triangle
sta FT_OUT_BUF+6
lda FT_SFX_BUF+7,x
sta FT_OUT_BUF+7
lda FT_SFX_BUF+8,x
sta FT_OUT_BUF+8
@no_triangle:
lda FT_OUT_BUF+9 ;same as for pulse 1 and 2, but for noise
and #$0f
sta <FT_TEMP_VAR1
lda FT_SFX_BUF+9,x
and #$0f
cmp <FT_TEMP_VAR1
bcc @no_noise
lda FT_SFX_BUF+9,x
sta FT_OUT_BUF+9
lda FT_SFX_BUF+10,x
sta FT_OUT_BUF+10
@no_noise:
rts
.endif
;dummy envelope used to initialize all channels with silence
_FT2DummyEnvelope:
.byte $c0,$00,$00
;PAL and NTSC, 11-bit dividers
;rest note, then octaves 1-5, then three zeroes
;first 64 bytes are PAL, next 64 bytes are NTSC
_FT2NoteTableLSB:
.if(FT_PAL_SUPPORT)
.byte $00,$33,$da,$86,$36,$eb,$a5,$62,$23,$e7,$af,$7a,$48,$19,$ec,$c2
.byte $9a,$75,$52,$30,$11,$f3,$d7,$bc,$a3,$8c,$75,$60,$4c,$3a,$28,$17
.byte $08,$f9,$eb,$dd,$d1,$c5,$ba,$af,$a5,$9c,$93,$8b,$83,$7c,$75,$6e
.byte $68,$62,$5c,$57,$52,$4d,$49,$45,$41,$3d,$3a,$36,$33,$30,$2d,$2b
.endif
.if(FT_NTSC_SUPPORT)
.byte $00,$ad,$4d,$f2,$9d,$4c,$00,$b8,$74,$34,$f7,$be,$88,$56,$26,$f8
.byte $ce,$a5,$7f,$5b,$39,$19,$fb,$de,$c3,$aa,$92,$7b,$66,$52,$3f,$2d
.byte $1c,$0c,$fd,$ee,$e1,$d4,$c8,$bd,$b2,$a8,$9f,$96,$8d,$85,$7e,$76
.byte $70,$69,$63,$5e,$58,$53,$4f,$4a,$46,$42,$3e,$3a,$37,$34,$31,$2e
.endif
_FT2NoteTableMSB:
.if(FT_PAL_SUPPORT)
.byte $00,$06,$05,$05,$05,$04,$04,$04,$04,$03,$03,$03,$03,$03,$02,$02
.byte $02,$02,$02,$02,$02,$01,$01,$01,$01,$01,$01,$01,$01,$01,$01,$01
.byte $01,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
.byte $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
.endif
.if(FT_NTSC_SUPPORT)
.byte $00,$06,$06,$05,$05,$05,$05,$04,$04,$04,$03,$03,$03,$03,$03,$02
.byte $02,$02,$02,$02,$02,$02,$01,$01,$01,$01,$01,$01,$01,$01,$01,$01
.byte $01,$01,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
.byte $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
.endif
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