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|
;****************************************************************************
; NoteOnFM* [events $00~$07]
; Does a "note on" for a FM channel
;----------------------------------------------------------------------------
; input a .... FM channel (bottom 3 bits)
; input c .... current bank
; input hl ... current address
;----------------------------------------------------------------------------
; breaks: af, b
;****************************************************************************
NoteOnFMSFX:
call NoteOnFM ; We're just a wrapper
jp ProcessSFXRun ; End of subroutine
NoteOnFMBGM:
ld b, a
PollPCM
push hl
ld a, b
and $07 ; Check if channel is free
ld hl, RAM_Locked
add l
ld l, a
ld a, (hl)
pop hl
or a
jp nz, ProcessBGMSkip1 ; Don't play if locked
ld a, b
call NoteOnFM ; We're just a wrapper
jp ProcessBGMRun ; End of subroutine
NoteOnFM:
and $07 ; Get channel ID
ld (ix+0), $28 ; Note off
ld (ix+1), a
ld b, a
ex af, af'
PollPCM
ld a, b ; Determine which port to write
and $04
rrca
ld iyl, a
PollPCM
call GetParam ; Get note
PollPCM
ex af, af'
push de
push hl
ld d, a
and $03 ; Index of first frequency register
add $A4
ld e, a
PollPCM
ld h, FMFreqTable>>8 ; Get address of note
ld a, b
and $1F
add FMFreqTable&$FF
ld l, a
PollPCM
ld a, b ; Set new frequency
and $E0
rrca
rrca
ld b, a
ld a, (hl)
or b
ld (iy+0), e
ld (iy+1), a
PollPCM
ld a, e
sub 4
ld e, a
dec l
ld a, (hl)
ld (iy+0), e
ld (iy+1), a
PollPCM
ld a, d ; Note on!
or $F0
ld (ix+0), $28
ld (ix+1), a
pop hl
pop de
ret ; End of subroutine
;****************************************************************************
; NoteOffFM [events $10~$17]
; Does a "note off" for a FM channel
;----------------------------------------------------------------------------
; input a .... FM channel (bottom 3 bits)
; input c .... current bank
; input hl ... current address
;----------------------------------------------------------------------------
; breaks: af, b
;****************************************************************************
NoteOffFMSFX:
call NoteOffFM ; We're just a wrapper
jp ProcessSFXRun ; End of subroutine
NoteOffFMBGM:
ld b, a
PollPCM
ld a, b
push hl
and $07 ; Check if channel is free
ld hl, RAM_Locked
add l
ld l, a
ld a, (hl)
pop hl
or a
jp nz, ProcessBGMSkip ; Don't stop if locked
ld a, b
call NoteOffFM ; We're just a wrapper
jp ProcessBGMRun ; End of subroutine
NoteOffFM:
and $07 ; Get channel ID
ld (ix+0), $28 ; Note off
ld (ix+1), a
ret ; End of subroutine
;****************************************************************************
; SetFMNote* [events $30~$37]
; Sets the note of a FM channel without "note on"
;----------------------------------------------------------------------------
; input a .... FM channel (bottom 3 bits)
; input c .... current bank
; input hl ... current address
;----------------------------------------------------------------------------
; breaks: af, b
;****************************************************************************
SetNoteFMSFX:
call SetNoteFM ; We're just a wrapper
jp ProcessSFXRun ; End of subroutine
SetNoteFMBGM:
ld b, a
PollPCM
ld a, b
push hl
and $07 ; Check if channel is free
ld hl, RAM_Locked
add l
ld l, a
ld a, (hl)
pop hl
or a
jp nz, ProcessBGMSkip2 ; Don't change if locked
ld a, b
call SetNoteFM ; We're just a wrapper
jp ProcessBGMRun ; End of subroutine
SetNoteFM:
push af
ld b, a
PollPCM
ld a, b ; Determine which port to write
and $04
rrca
ld iyl, a
PollPCM
call GetParam ; Get high byte
PollPCM
pop af
push de
and $07
ld d, a
and $03 ; Index of first frequency register
add $A4
ld e, a
PollPCM
ld (iy+0), e ; Load high byte
ld (iy+1), b
PollPCM ; Load low byte
call GetParam
PollPCM
ld a, e
sub 4
ld e, a
ld (iy+0), e
ld (iy+1), b
PollPCM
pop de
ret ; End of subroutine
;****************************************************************************
; LoadFM* [events $40~$47]
; Loads a FM instrument
;----------------------------------------------------------------------------
; input a .... FM channel (bottom 3 bits)
; input c .... current bank
; input hl ... current address
;----------------------------------------------------------------------------
; breaks: af, b
;****************************************************************************
LoadFMSFX:
call LoadFMEvent ; We're just a wrapper
jp ProcessSFXRun ; End of subroutine
LoadFMBGM:
and $07 ; Get channel ID
ld b, a
PollPCM
push de
push bc
ld a, b
ld de, RAM_BGMFMInstr ; Store instrument ID
add e
ld e, a
PollPCM
call GetParam
PollPCM
ld a, b
ld (de), a
ld a, e ; Reset volume
add 8
ld e, a
xor a
ld (de), a
ld e, c
pop bc
ld c, e
pop de
PollPCM
push hl ; Check if channel is free
ld a, b
ld h, RAM_Locked>>8
add RAM_Locked&$FF
ld l, a
ld a, (hl)
pop hl
or a
jp nz, ProcessBGMSkip ; Don't load if locked
PollPCM
ld a, b ; Get back instrument ID
push hl
ld hl, RAM_BGMFMInstr
add l
ld l, a
ld b, (hl)
pop hl
ex af, af'
PollPCM
ex af, af'
call LoadFMDirect ; We're just a wrapper
jp ProcessBGMRun ; End of subroutine
LoadFMEvent:
and $07 ; Get channel ID
ex af, af'
PollPCM
call GetParam ; Get instrument ID
PollPCM
ex af, af'
LoadFMDirect:
push af
and $04 ; Determine which port to write
rrca
ld iyl, a
PollPCM
pop af
push bc
push de
push hl
ld h, RAM_PointerList>>8 ; Get instrument address
ld l, b
ld d, (hl)
inc h
ld e, (hl)
inc h
ld c, (hl)
ex de, hl
push af
PollPCM
ld b, 28/4 ; Load FM instrument into our scratch buffer,
ld de, RAM_Scratch ; so we don't conflict with PCM bank
.getinstr: ; switch (which would slow down A LOT)
ld a, b
ex af, af'
call GetParam
ex de, hl
ld (hl), b
ex de, hl
inc e
call GetParam
ex de, hl
ld (hl), b
ex de, hl
inc e
call GetParam
ex de, hl
ld (hl), b
ex de, hl
inc e
call GetParam
ex de, hl
ld (hl), b
ex de, hl
inc e
ex af, af'
ld b, a
djnz .getinstr
call GetParam
ex de, hl
ld (hl), b
ex de, hl
PollPCM
pop af ; Kill ADSR
ld b, a
call KillFM
ld a, b
ld de, RAM_FMData ; Get address of FM data
and $07
add e
ld e, a
push af
and $03 ; Register index for operator
add $B0
ld hl, RAM_Scratch ; Get address of buffer with the instrument
; data
ex af, af'
PollPCM ; Write operator
ex af, af'
ld (iy+0), a
ld b, (hl)
inc l
ld (iy+1), b
ex af, af' ; Store $B0 register in FM data buffer
ld a, b
ld (de), a
ld a, e
add 8
ld e, a
PollPCM
ex af, af'
sub $B0-$30
ld b, 7*4 ; Load operator registers into the YM2612
.loadfmloop:
ld (iy+0), a
ld c, (hl)
ld (iy+1), c
add 4
inc l
djnz .loadfmloop
PollPCM
ld a, l ; Store operator TLs (needed to set the
sub 24 ; volume properly when it changes)
ld l, a
ld b, 4
.loadfmsavetl:
ld a, (hl)
ld (de), a
ld a, e
add 8
ld e, a
inc l
djnz .loadfmsavetl
PollPCM
pop af
pop hl
pop de
pop bc
ld b, 0
jp SetFMVolLoad
;****************************************************************************
; SetFMVol*
; Sets the volume of a FM channel
;****************************************************************************
SetFMVolSFX:
call SetFMVolSFXEvent ; We're just a wrapper
jp ProcessSFXRun ; End of subroutine
SetFMVolBGM:
and $07
ld b, a
PollPCM
push de
push bc
ld a, b
ld d, RAM_BGMFMVol>>8 ; Store BGM volume
add RAM_BGMFMVol&$FF
ld e, a
PollPCM
call GetParam
PollPCM
ex de, hl
ld (hl), b
ex de, hl
ld e, c
pop bc
ld c, e
pop de
PollPCM
push hl
ld a, b ; Check if channel is free
ld hl, RAM_Locked
add l
ld l, a
ld a, (hl)
pop hl
or a
jp nz, ProcessBGMSkip ; Don't change if locked
PollPCM
ld a, b
push hl
ld hl, RAM_BGMFMVol
add l
ld l, a
ld b, (hl)
pop hl
push af
PollPCM
pop af
call SetFMVolLoad ; We're just a wrapper
jp ProcessBGMRun ; End of subroutine
SetFMVolSFXEvent:
push af
PollPCM
call GetParam ; Get new volume
PollPCM
pop af
SetFMVolLoad:
push bc
push de
push hl
and $07 ; Get channel ID
push af ; Store new FM volume
ld h, RAM_FMVol>>8
add RAM_FMVol&$FF
ld l, a
ld (hl), b
pop af
push af
ld h, RAM_FMData>>8 ; Get address of FM data
add RAM_FMData&$FF
ld l, a
ex af, af'
PollPCM
ex af, af'
and $07 ; Get global volume
or $E0
ld d, $1F
ld e, a
ex af, af'
ld a, (de)
ld d, a
PollPCM
ex af, af'
and $04 ; Determine which port to write
rrca
ld iyl, a
PollPCM
pop af
and $03 ; Index of first volume register
add $40
ld c, a
ld a, (hl) ; Get algorithm
and $07
ld e, a
PollPCM
ld a, l
add 8
ld l, a
ld a, e ; Process operator #1
cp $07
jr c, .noop1
ld (iy+0), c
ld a, (hl)
add d
jp m, .tooquiet1
add b
jp p, .notooquiet1
.tooquiet1:
ld a, $7F
.notooquiet1:
ld (iy+1), a
.noop1:
ld a, c
add 4
ld c, a
PollPCM
ld a, l
add 8
ld l, a
ld a, e ; Process operator #2
cp $05
jr c, .noop2
ld (iy+0), c
ld a, (hl)
add d
jp m, .tooquiet2
add b
jp p, .notooquiet2
.tooquiet2:
ld a, $7F
.notooquiet2:
ld (iy+1), a
.noop2:
ld a, c
add 4
ld c, a
PollPCM
ld a, l
add 8
ld l, a
ld a, e ; Process operator #3
cp $04
jr c, .noop3
ld (iy+0), c
ld a, (hl)
add d
jp m, .tooquiet3
add b
jp p, .notooquiet3
.tooquiet3:
ld a, $7F
.notooquiet3:
ld (iy+1), a
.noop3:
ld a, c
add 4
ld c, a
PollPCM
ld a, l
add 8
ld l, a
ld (iy+0), c
ld a, (hl) ; Process operator #4
add d
jp m, .tooquiet4
add b
jp p, .notooquiet4
.tooquiet4:
ld a, $7F
.notooquiet4:
ld (iy+1), a
PollPCM
pop hl
pop de
pop bc
ret ; End of subroutine
;****************************************************************************
; SetFMParam* [events $F0-$F7]
; Sets the different parameters of a FM channel
;----------------------------------------------------------------------------
; input c .... current bank
; input hl ... current address
;----------------------------------------------------------------------------
; output b .... value
; output c .... new bank
; output hl ... new address
;----------------------------------------------------------------------------
; breaks: af, b
;****************************************************************************
SetFMParamSFX:
ld b, a
PollPCM
ld a, b ; Determine which port to write
and $04
rrca
ld iyl, a
ld a, b
ex af, af'
PollPCM
call GetParam ; Get parameters
PollPCM
ex af, af'
and $03 ; Get channel ID
add $B4
ld (iy+0), a ; Set new parameters
ld (iy+1), b
jp ProcessSFXRun ; End of subroutine
SetFMParamBGM:
ld b, a
PollPCM
ld a, b ; Determine which port to write
and $04
rrca
ld iyl, a
ld a, b
ex af, af'
PollPCM
call GetParam ; Get parameters
PollPCM
ex af, af'
push hl
and $07 ; Store parameters
ld h, RAM_BGMFMPan>>8
add RAM_BGMFMPan&$FF
ld l, a
ld (hl), b
ex af, af'
PollPCM
ex af, af'
and $07 ; Check if channel is free
add RAM_Locked&$FF
ld l, a
ex af, af'
ld a, (hl)
or a
pop hl
jp nz, ProcessBGMRun ; Don't modify if locked
PollPCM
ex af, af'
and $03 ; Get channel ID
add $B4
ld (iy+0), a ; Set new parameters
ld (iy+1), b
jp ProcessBGMRun ; End of subroutine
;****************************************************************************
; SetFMReg* [events $F8-$F9]
; Changes a FM register
;----------------------------------------------------------------------------
; input a .... YM2612 register bank (0 or 1, in bit 0)
; input c .... current bank
; input hl ... current address
;----------------------------------------------------------------------------
; output b .... value
; output c .... new bank
; output hl ... new address
;----------------------------------------------------------------------------
; breaks: af, b
;****************************************************************************
SetFMRegSFX:
call SetFMReg ; We're just a wrapper
jp ProcessSFXRun
SetFMRegBGM:
call SetFMReg ; We're just a wrapper
jp ProcessBGMRun
;----------------------------------------------------------------------------
SetFMReg:
and $01 ; Get port address
add a
ld iyl, a
PollPCM ; Get parameters
call GetParam
push bc
PollPCM
call GetParam
PollPCM
ld a, b
pop bc
ld (iy+0), b ; Write register
ld (iy+1), a
ret ; End of subroutine
;****************************************************************************
; LockChannelFM [events $E0-$E7]
; Locks a FM channel
;----------------------------------------------------------------------------
; input a ... FM channel (0..7, in bottom 3 bits)
; input c .... current bank
; input hl ... current address
;----------------------------------------------------------------------------
; output b .... value
; output c .... new bank
; output hl ... new address
;----------------------------------------------------------------------------
; breaks: af, iy
;****************************************************************************
LockChannelFM:
and $07
ld b, a
PollPCM
push hl
ld h, RAM_Locked>>8 ; Get address of channel to lock
ld a, b
add RAM_Locked&$FF
ld l, a
ld (hl), $01 ; Lock channel
pop hl
PollPCM
ld a, b ; Determine which port to write
and $04
rrca
ld iyl, a
ld a, b ; Reset FM parameters
and $03
add a
add a
add $B4
ld (iy+0), a
ld (iy+1), $C0
jp ProcessSFXRun ; End of subroutine
;****************************************************************************
; KillFM
; Kills a FM channel
;----------------------------------------------------------------------------
; input a ... FM channel (0..7, in bottom 3 bits)
;----------------------------------------------------------------------------
; breaks: af, c, iy
;****************************************************************************
KillFM:
and $07 ; Get channel ID
push af
push de
push hl
ld c, a ; Determine to which port to write
and $04
rrca
ld iyl, a
ld a, c
and $03 ; Load dummy FM instrument
add $40
ld c, 6
ld hl, DummyFMInstr
.loaddummy:
ex af, af'
PollPCM
ex af, af'
ld e, (hl)
ld (iy+0), a
ld (iy+1), e
add 4
ex af, af'
PollPCM
ex af, af'
ld (iy+0), a
ld (iy+1), e
add 4
ex af, af'
PollPCM
ex af, af'
ld (iy+0), a
ld (iy+1), e
add 4
ex af, af'
PollPCM
ex af, af'
ld (iy+0), a
ld (iy+1), e
add 4
inc l
dec c
jp nz, .loaddummy
pop hl
pop de
PollPCM
pop af
ld c, a ; Cause the ADSR to reset
or $F0
ld (ix+0), $28
ld (ix+1), c
ld (ix+0), $28
ld (ix+1), a
ld (ix+0), $28
ld (ix+1), c
PollPCM
ret ; End of subroutine
;****************************************************************************
; RestoreFM
; Restores a FM channel (from BGM information)
;----------------------------------------------------------------------------
; input b ... FM channel (0..7)
;----------------------------------------------------------------------------
; breaks: af, hl
;****************************************************************************
RestoreFM:
ld a, b ; Restore BGM FM instrument
ld h, RAM_BGMFMInstr>>8
add RAM_BGMFMInstr&$FF
ld l, a
push bc
ld a, b
ld b, (hl)
call LoadFMDirect
pop bc
PollPCM
push bc
ld a, l ; Restore BGM FM volume
add 8
ld l, a
ld a, b
ld b, (hl)
call SetFMVolLoad
pop bc
ld a, l ; Restore BGM FM panning
add 8
ld l, a
ld a, b
and $03
add $B4
ld (iy+0), a
ld a, (hl)
ld (iy+1), a
PollPCM
ret ; End of subroutine
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