789 lines
78 KiB
Plaintext
789 lines
78 KiB
Plaintext
{{
|
|
┌──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
|
|
│ SIDcog - SID/MOS8580 emulator V0.80 (C) 2010-02 Johannes Ahlebrand │
|
|
├──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┤
|
|
│ TERMS OF USE: Parallax Object Exchange License │
|
|
├──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┤
|
|
│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. │
|
|
└──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘
|
|
}}
|
|
{
|
|
|
|
11-07-2010-dr235 - änderung in setWaveform
|
|
|
|
}
|
|
|
|
|
|
CON PAL = 985248.0, NTSC = 1022727.0, MAXF = 1031000.0, TRIANGLE = 16, SAW = 32, SQUARE = 64, NOISE = 128
|
|
|
|
C64_CLOCK_FREQ = PAL
|
|
' ___
|
|
CUTOFF_LIMIT = 1300' │
|
|
LP_MAX_CUTOFF = 10' │
|
|
BP_MAX_CUTOFF = 11' │ Don't alter these unless you know what you are doing. ;)
|
|
FILTER_OFFSET = 27' │
|
|
DECAY_DIVIDE_REF = $6C6C6C6C' │
|
|
NOISE_ADD = $979D21B5' │
|
|
NOISE_ROTATE = 28' ___│
|
|
|
|
PUB start(right,left)
|
|
arg1 := $18000000 | left
|
|
arg2 := $18000000 | right
|
|
r1 := ((1<<right) | (1<<left))&!1
|
|
sampleRate := clkfreq/trunc(C64_CLOCK_FREQ/32.0)
|
|
combTableAddr := @combinedWaveforms
|
|
cog := cognew(@SIDEMU, @ch1_frequencyLo) + 1
|
|
return @ch1_frequencyLo
|
|
|
|
PUB stop
|
|
if cog
|
|
cogstop(cog~ -1)
|
|
|
|
PUB setRegister(reg,val)
|
|
byte[@ch1_frequencyLo+(reg+(reg/7))] := val
|
|
|
|
PUB updateRegisters(source)
|
|
bytemove(@ch1_frequencyLo , source , 7)
|
|
bytemove(@ch1_frequencyLo+8 , source+7 , 7)
|
|
bytemove(@ch1_frequencyLo+16, source+14, 7)
|
|
bytemove(@ch1_frequencyLo+24, source+21, 4)
|
|
|
|
PUB getSample
|
|
return long[@SIDSample]
|
|
|
|
PUB setVolume(value)
|
|
byte[@Volume] := (byte[@Volume]&$F0) | (value&$0F)
|
|
|
|
PUB play(channel, freq, waveform, attack, decay, sustain, release) | offs
|
|
offs := channel<<3
|
|
word[@ch1_frequencyLo+offs] := freq
|
|
byte[@ch1_attackDecay+offs] := (decay&$F) | ((attack&$F)<<4)
|
|
byte[@ch1_sustainRelease+offs] := (release&$F) | ((sustain&$F)<<4)
|
|
byte[@ch1_controlRegister+offs] := (byte[@ch1_controlRegister+offs]&$0F) | waveform | 1
|
|
|
|
PUB noteOn(channel, freq) | offs
|
|
offs := channel<<3
|
|
byte[@ch1_controlRegister+offs] := (byte[@ch1_controlRegister+offs]&$FE) | 1
|
|
word[@ch1_frequencyLo+offs] := freq
|
|
|
|
PUB noteOff(channel)
|
|
byte[@ch1_controlRegister+(channel<<3)] &= $FE
|
|
|
|
PUB setFreq(channel,freq)
|
|
word[@ch1_frequencyLo+(channel<<3)] := freq
|
|
|
|
PUB setWaveform(channel,waveform) | offs
|
|
offs := channel<<3
|
|
byte[@ch1_controlRegister+offs] := (byte[@ch1_controlRegister+offs]&$0F) | waveform
|
|
' byte[@ch1_controlRegister+offs] := (byte[@ch1_controlRegister+offs]&$0F) | (1<<(4+(waveform&3)))
|
|
|
|
PUB setPWM(channel, value)
|
|
word[@ch1_pulseWidthLo+(channel<<3)] := value
|
|
|
|
PUB setADSR(channel, attack, decay, sustain, release ) | offs
|
|
offs := channel<<3
|
|
byte[@ch1_attackDecay+offs] := (decay&$F) | ((attack&$F)<<4)
|
|
byte[@ch1_sustainRelease+offs] := (release&$F) | ((sustain&$F)<<4)
|
|
|
|
PUB setResonance(val)
|
|
byte[@Filter3] := (byte[@Filter3]&$0F) | (val<<4)
|
|
|
|
PUB setCutoff(freq)
|
|
byte[@Filter1] := freq&$07
|
|
byte[@Filter2] := (freq&$07F8)>>3
|
|
|
|
PUB setFilterMask(ch1,ch2,ch3)
|
|
byte[@Filter3] := (byte[@Filter3]&$F0) | (ch1&1) | (ch2&2) | (ch3&4)
|
|
|
|
PUB setFilterType(lp,bp,hp)
|
|
byte[@volume] := (byte[@volume]&$0F) | (lp&16) | (bp&32) | (hp&64)
|
|
|
|
PUB enableRingmod(ch1,ch2,ch3)
|
|
byte[@ch1_controlRegister] := (byte[@ch1_controlRegister]&$FB) | (ch1&4)
|
|
byte[@ch2_controlRegister] := (byte[@ch2_controlRegister]&$FB) | (ch2&4)
|
|
byte[@ch3_controlRegister] := (byte[@ch3_controlRegister]&$FB) | (ch3&4)
|
|
|
|
PUB enableSynchronization(ch1,ch2,ch3)
|
|
byte[@ch1_controlRegister] := (byte[@ch1_controlRegister]&$FD) | (ch1&2)
|
|
byte[@ch2_controlRegister] := (byte[@ch2_controlRegister]&$FD) | (ch2&2)
|
|
byte[@ch3_controlRegister] := (byte[@ch3_controlRegister]&$FD) | (ch3&2)
|
|
|
|
dat org 0
|
|
'
|
|
' Assembly SID emulator
|
|
'
|
|
SIDEMU mov dira, r1
|
|
mov ctra, arg1
|
|
mov ctrb, arg2
|
|
mov waitCounter, cnt
|
|
add waitCounter, sampleRate
|
|
'-----------------------------------------------------------
|
|
mainLoop call #getRegisters
|
|
call #SID
|
|
call #filter
|
|
call #mixer
|
|
jmp #mainLoop
|
|
'-----------------------------------------------------------
|
|
|
|
'
|
|
' Read all SID-registers from hub memory and convert
|
|
' them to more convenient representations.
|
|
'
|
|
getRegisters mov tempValue, par ' Read in first long ( 16bit frequency / 16bit pulse-width )
|
|
rdlong frequency1, tempValue
|
|
mov pulseWidth1, frequency1
|
|
shl pulseWidth1, #4 ' Shift in "12 bit" pulse width value( make it 32 bits )
|
|
andn pulseWidth1, mask20bit
|
|
and frequency1, mask16bit ' Mask out 16 bit frequency value
|
|
shl frequency1, #13
|
|
'-----------------------------------------------------------
|
|
add tempValue, #4 ' Read in next long ( Control register / ADSR )
|
|
rdlong selectedWaveform1, tempValue
|
|
mov controlRegister1, selectedWaveform1
|
|
'-----------------------------------------------------------
|
|
mov arg1, selectedWaveform1 '|
|
|
shr arg1, #8 '|
|
|
call #getDecay '|
|
|
mov decay1, r1 '|
|
|
shr arg1, #4 '|
|
|
call #getAttack '|
|
|
mov attack1, r1 '| Convert 4bit ADSR "presets" to their corresponding
|
|
shr arg1, #4 '| 32bit values using attack/decay tables.
|
|
call #getDecay '|
|
|
mov release1, r1 '|
|
|
mov sustain1, selectedWaveform1 '|
|
|
shl sustain1, #8 '|
|
|
andn sustain1, mask28bit '|
|
|
'-----------------------------------------------------------
|
|
shr selectedWaveform1, #4 ' Mask out waveform selection
|
|
and selectedWaveform1, #15 wz, wc
|
|
'-----------------------------------------------------------
|
|
test controlRegister1, #1 wc
|
|
cmp envelopeState1, #2 wz
|
|
if_z_and_c mov envelopeState1, #0
|
|
if_nz_and_nc mov envelopeState1, #2
|
|
|
|
'───────────────────────────────────────────────────────────
|
|
' Channel 2
|
|
'───────────────────────────────────────────────────────────
|
|
add tempValue, #4 ' Read in first long ( 16bit frequency / 16bit pulse-width )
|
|
rdlong frequency2, tempValue
|
|
mov pulseWidth2, frequency2
|
|
shl pulseWidth2, #4 ' Shift in "12 bit" pulse width value( make it 32 bits )
|
|
andn pulseWidth2, mask20bit
|
|
and frequency2, mask16bit ' Mask out 16 bit frequency value
|
|
shl frequency2, #13
|
|
'-----------------------------------------------------------
|
|
add tempValue, #4 ' Read in next long ( Control register / ADSR )
|
|
rdlong selectedWaveform2, tempValue
|
|
mov controlRegister2, selectedWaveform2
|
|
'-----------------------------------------------------------
|
|
mov arg1, selectedWaveform2 '|
|
|
shr arg1, #8 '|
|
|
call #getDecay '|
|
|
mov decay2, r1 '|
|
|
shr arg1, #4 '|
|
|
call #getAttack '|
|
|
mov attack2, r1 '| Convert 4bit ADSR "presets" to their corresponding
|
|
shr arg1, #4 '| 32bit values using attack/decay tables.
|
|
call #getDecay '|
|
|
mov release2, r1 '|
|
|
mov sustain2, selectedWaveform2 '|
|
|
shl sustain2, #8 '|
|
|
andn sustain2, mask28bit '|
|
|
'-----------------------------------------------------------
|
|
shr selectedWaveform2, #4 ' Mask out waveform selection
|
|
and selectedWaveform2, #15 wz, wc
|
|
'-----------------------------------------------------------
|
|
test controlRegister2, #1 wc
|
|
cmp envelopeState2, #2 wz
|
|
if_z_and_c mov envelopeState2, #0
|
|
if_nz_and_nc mov envelopeState2, #2
|
|
|
|
'───────────────────────────────────────────────────────────
|
|
' Channel 3
|
|
'───────────────────────────────────────────────────────────
|
|
add tempValue, #4 ' Read in first long ( 16bit frequency / 16bit pulse-width )
|
|
rdlong frequency3, tempValue '
|
|
mov pulseWidth3, frequency3
|
|
shl pulseWidth3, #4 ' Shift in "12 bit" pulse width value( make it 32 bits )
|
|
andn pulseWidth3, mask20bit
|
|
and frequency3, mask16bit ' Mask out 16 bit frequency value
|
|
shl frequency3, #13
|
|
'-----------------------------------------------------------
|
|
add tempValue, #4 ' Read in next long ( Control register / ADSR )
|
|
rdlong selectedWaveform3, tempValue
|
|
mov controlRegister3, selectedWaveform3
|
|
'-----------------------------------------------------------
|
|
mov arg1, selectedWaveform3 '|
|
|
shr arg1, #8 '|
|
|
call #getDecay '|
|
|
mov decay3, r1 '|
|
|
shr arg1, #4 '|
|
|
call #getAttack '|
|
|
mov attack3, r1 '| Convert 4bit ADSR "presets" to their corresponding
|
|
shr arg1, #4 '| 32bit values using attack/decay tables.
|
|
call #getDecay '|
|
|
mov release3, r1 '|
|
|
mov sustain3, selectedWaveform3 '|
|
|
shl sustain3, #8 '|
|
|
andn sustain3, mask28bit '|
|
|
'-----------------------------------------------------------
|
|
shr selectedWaveform3, #4 ' Mask out waveform selection
|
|
and selectedWaveform3, #15 wz, wc
|
|
'-----------------------------------------------------------
|
|
test controlRegister3, #1 wc
|
|
cmp envelopeState3, #2 wz
|
|
if_z_and_c mov envelopeState3, #0
|
|
if_nz_and_nc mov envelopeState3, #2
|
|
|
|
'───────────────────────────────────────────────────────────
|
|
' Filter / Volume
|
|
'───────────────────────────────────────────────────────────
|
|
add tempValue, #4 '|
|
|
rdlong filterControl, tempValue '|
|
|
mov filterCutoff, filterControl '|
|
|
'-----------------------------------------------------------
|
|
shr filterControl, #16 '| Filter control
|
|
'-----------------------------------------------------------
|
|
shr filterCutoff, #5 '|
|
|
andn filterCutoff, #7 '|
|
|
mov tempValue, filterControl '|
|
|
and tempValue, #7 '| Filter cutoff frequency
|
|
or filterCutoff, tempValue '|
|
|
and filterCutoff, mask11bit '|
|
|
add filterCutoff, filterOffset '|
|
|
'-----------------------------------------------------------
|
|
mov filterMode_Volume, filterControl '| Main volume and filter mode
|
|
shr filterMode_Volume, #8 '|
|
|
'-----------------------------------------------------------
|
|
mov filterResonance,filterControl '|
|
|
and filterResonance,#$F0 '|
|
|
shr filterResonance,#5 '|
|
|
add filterResonance,#resTable '| Filter Resonance level (Ariba)
|
|
movs rdRes,filterResonance '|
|
|
nop '|
|
|
rdRes mov filterResonance,0-0 '|
|
|
|
|
getRegisters_ret ret
|
|
|
|
'
|
|
' Calculate sid samples channel 1-3 and store in out1-out3
|
|
'
|
|
|
|
'───────────────────────────────────────────────────────────
|
|
' Increment phase accumulator 1-3 and handle syncing
|
|
'───────────────────────────────────────────────────────────
|
|
SID add phaseAccumulator1, frequency1 wc ' Add frequency value to phase accumulator 1
|
|
if_nc andn controlRegister2, #2
|
|
test controlRegister2, #10 wz ' Sync oscilator 2 to oscilator 1 if sync = on
|
|
if_nz mov phaseAccumulator2, #0 ' Or reset counter 2 when bit 4 of control register is 1
|
|
'-----------------------------------------------------------
|
|
add phaseAccumulator2, frequency2 wc
|
|
if_nc andn controlRegister3, #2
|
|
test controlRegister3, #10 wz ' Sync oscilator 3 to oscilator 2 if sync = on
|
|
if_nz mov phaseAccumulator3, #0 ' Or reset oscilator 3 when bit 4 of control register is 1
|
|
'-----------------------------------------------------------
|
|
add phaseAccumulator3, frequency3 wc
|
|
if_nc andn controlRegister1, #2
|
|
test controlRegister1, #10 wz ' Sync oscilator 1 to oscilator 3 if sync = on
|
|
if_nz mov phaseAccumulator1, #0 ' Or reset oscilator 1 when bit 4 of control register is 1
|
|
|
|
'───────────────────────────────────────────────────────────
|
|
' Waveform shaping channel 1 -> arg1
|
|
'───────────────────────────────────────────────────────────
|
|
Triangle1 tjz selectedWaveform1, #Triangle2
|
|
cmp selectedWaveform1, #1 wz
|
|
if_nz jmp #Saw1
|
|
abs arg1, phaseAccumulator1
|
|
max arg1, mask31bit
|
|
test controlRegister1, #4 wc '|
|
|
if_c test phaseAccumulator3, val31bit wc '| These 3 lines handles ring modulation
|
|
if_c xor arg1, mask32bit '|
|
|
shl arg1, #1
|
|
jmp #Env_Attack1
|
|
'-----------------------------------------------------------
|
|
Saw1 cmp selectedWaveform1, #2 wz
|
|
if_z mov arg1, phaseAccumulator1
|
|
if_z jmp #Env_Attack1
|
|
'-----------------------------------------------------------
|
|
Square1 cmp selectedWaveform1, #4 wz
|
|
if_z sub pulseWidth1, phaseAccumulator1 wc ' C holds the pulse width modulated square wave
|
|
if_z muxc arg1, mask32bit
|
|
if_z jmp #Env_Attack1
|
|
'-----------------------------------------------------------
|
|
Noise1 cmp selectedWaveform1, #8 wz
|
|
if_nz jmp #Combined1
|
|
mov tempValue, phaseAccumulator1
|
|
and tempValue, mask28bit
|
|
sub tempValue, frequency1 wc
|
|
if_z_and_c ror noiseValue1, NOISE_ROTATE
|
|
if_z_and_c add noiseValue1, noiseAdd
|
|
if_z mov arg1, noiseValue1
|
|
jmp #Env_Attack1
|
|
'-----------------------------------------------------------
|
|
Combined1 sub selectedWaveform1, #4
|
|
mins selectedWaveform1, #0
|
|
shl selectedWaveform1, #8
|
|
mov tempValue, phaseAccumulator1
|
|
shr tempValue, #24
|
|
add selectedWaveform1, tempValue
|
|
add selectedWaveform1, combTableAddr
|
|
rdbyte arg1, selectedWaveform1
|
|
shl arg1, #24
|
|
|
|
'───────────────────────────────────────────────────────────
|
|
' Envelope shaping channel 1 -> arg2
|
|
'───────────────────────────────────────────────────────────
|
|
Env_Attack1 cmp envelopeState1, #0 wz
|
|
if_nz jmp #InitDecay1
|
|
add envelopeLevel1, attack1 wc
|
|
if_c mov envelopeLevel1, mask32bit
|
|
if_c mov envelopeState1, #1
|
|
mov decayDivide1, #0
|
|
jmp #Amplitude1
|
|
'-----------------------------------------------------------
|
|
InitDecay1 mov tempValue, decayDivideRef
|
|
shr tempValue, decayDivide1
|
|
cmp envelopeLevel1, tempValue wc
|
|
if_c add decayDivide1, #1
|
|
'-----------------------------------------------------------
|
|
Env_Decay1 cmp envelopeState1, #1 wz
|
|
if_nz jmp #Env_Release1
|
|
shr decay1, decayDivide1
|
|
sub envelopeLevel1, decay1
|
|
min envelopeLevel1, sustain1 wc
|
|
jmp #Amplitude1
|
|
'-----------------------------------------------------------
|
|
Env_Release1 cmp envelopeState1, #2 wz
|
|
if_nz jmp #Amplitude1
|
|
shr release1, decayDivide1
|
|
cmpsub envelopeLevel1, release1
|
|
|
|
'───────────────────────────────────────────────────────────
|
|
'Calculate sample out1 = arg1 * arg2 (waveform * amplitude)
|
|
'───────────────────────────────────────────────────────────
|
|
Amplitude1 shr arg1, #16
|
|
sub arg1, val15bit
|
|
mov arg2, envelopeLevel1
|
|
shr arg2, #22
|
|
call #multiply
|
|
mov out1, r1
|
|
|
|
'───────────────────────────────────────────────────────────
|
|
' Waveform shaping channel 2 -> arg1
|
|
'───────────────────────────────────────────────────────────
|
|
Triangle2 tjz selectedWaveform2, #Triangle3
|
|
cmp selectedWaveform2, #1 wz
|
|
if_nz jmp #Saw2
|
|
abs arg1, phaseAccumulator2
|
|
max arg1, mask31bit
|
|
test controlRegister2, #4 wc '|
|
|
if_c test phaseAccumulator1, val31bit wc '| These 3 lines handles ring modulation
|
|
if_c xor arg1, mask32bit '|
|
|
shl arg1, #1
|
|
jmp #Env_Attack2
|
|
'-----------------------------------------------------------
|
|
Saw2 cmp selectedWaveform2, #2 wz
|
|
if_z mov arg1, phaseAccumulator2
|
|
if_z jmp #Env_Attack2
|
|
'-----------------------------------------------------------
|
|
Square2 cmp selectedWaveform2, #4 wz
|
|
if_z sub pulseWidth2, phaseAccumulator2 wc ' C holds the pulse width modulated square wave
|
|
if_z muxc arg1, mask32bit
|
|
if_z jmp #Env_Attack2
|
|
'-----------------------------------------------------------
|
|
Noise2 cmp selectedWaveform2, #8 wz
|
|
if_nz jmp #Combined2
|
|
mov tempValue, phaseAccumulator2
|
|
and tempValue, mask28bit
|
|
sub tempValue, frequency2 wc
|
|
if_z_and_c ror noiseValue2, NOISE_ROTATE
|
|
if_z_and_c add noiseValue2, noiseAdd
|
|
if_z mov arg1, noiseValue2
|
|
jmp #Env_Attack2
|
|
'-----------------------------------------------------------
|
|
Combined2 sub selectedWaveform2, #4
|
|
mins selectedWaveform2, #0
|
|
shl selectedWaveform2, #8
|
|
mov tempValue, phaseAccumulator2
|
|
shr tempValue, #24
|
|
add selectedWaveform2, tempValue
|
|
add selectedWaveform2, combTableAddr
|
|
rdbyte arg1, selectedWaveform2
|
|
shl arg1, #24
|
|
|
|
'───────────────────────────────────────────────────────────
|
|
' Envelope shaping channel 2 -> arg2
|
|
'───────────────────────────────────────────────────────────
|
|
Env_Attack2 cmp envelopeState2, #0 wz
|
|
if_nz jmp #InitDecay2
|
|
add envelopeLevel2, attack2 wc
|
|
if_c mov envelopeLevel2, mask32bit
|
|
if_c mov envelopeState2, #1
|
|
mov decayDivide2, #0
|
|
jmp #Amplitude2
|
|
'-----------------------------------------------------------
|
|
InitDecay2 mov tempValue, decayDivideRef
|
|
shr tempValue, decayDivide2
|
|
cmp envelopeLevel2, tempValue wc
|
|
if_c add decayDivide2, #1
|
|
'-----------------------------------------------------------
|
|
Env_Decay2 cmp envelopeState2, #1 wz
|
|
if_nz jmp #Env_Release2
|
|
shr decay2, decayDivide2
|
|
sub envelopeLevel2, decay2
|
|
min envelopeLevel2, sustain2 wc
|
|
jmp #Amplitude2
|
|
'-----------------------------------------------------------
|
|
Env_Release2 cmp envelopeState2, #2 wz
|
|
if_nz jmp #Amplitude2
|
|
shr release2, decayDivide2
|
|
cmpsub envelopeLevel2, release2
|
|
|
|
'───────────────────────────────────────────────────────────
|
|
'Calculate sample out2 = arg1 * arg2 (waveform * amplitude)
|
|
'───────────────────────────────────────────────────────────
|
|
Amplitude2 shr arg1, #16
|
|
sub arg1, val15bit
|
|
mov arg2, envelopeLevel2
|
|
shr arg2, #22
|
|
call #multiply
|
|
mov out2, r1
|
|
|
|
'───────────────────────────────────────────────────────────
|
|
' Waveform shaping channel 3 -> arg1
|
|
'───────────────────────────────────────────────────────────
|
|
Triangle3 tjz selectedWaveform3, #SID_ret
|
|
cmp selectedWaveform3, #1 wz
|
|
if_nz jmp #Saw3
|
|
abs arg1, phaseAccumulator3
|
|
max arg1, mask31bit
|
|
test controlRegister3, #4 wc '|
|
|
if_c test phaseAccumulator2, val31bit wc '| These 3 lines handles ring modulation
|
|
if_c xor arg1, mask32bit '|
|
|
shl arg1, #1
|
|
jmp #Env_Attack3
|
|
'-----------------------------------------------------------
|
|
Saw3 cmp selectedWaveform3, #2 wz
|
|
if_z mov arg1, phaseAccumulator3
|
|
if_z jmp #Env_Attack3
|
|
'-----------------------------------------------------------
|
|
Square3 cmp selectedWaveform3, #4 wz
|
|
if_z sub pulseWidth3, phaseAccumulator3 wc ' C holds the pulse width modulated square wave
|
|
if_z muxc arg1, mask32bit
|
|
if_z jmp #Env_Attack3
|
|
'-----------------------------------------------------------
|
|
Noise3 cmp selectedWaveform3, #8 wz
|
|
if_nz jmp #Combined3
|
|
mov tempValue, phaseAccumulator3
|
|
and tempValue, mask28bit
|
|
sub tempValue, frequency3 wc
|
|
if_z_and_c ror noiseValue3, NOISE_ROTATE
|
|
if_z_and_c add noiseValue3, noiseAdd
|
|
if_z mov arg1, noiseValue3
|
|
jmp #Env_Attack3
|
|
'-----------------------------------------------------------
|
|
Combined3 sub selectedWaveform3, #4
|
|
mins selectedWaveform3, #0
|
|
shl selectedWaveform3, #8
|
|
mov tempValue, phaseAccumulator3
|
|
shr tempValue, #24
|
|
add selectedWaveform3, tempValue
|
|
add selectedWaveform3, combTableAddr
|
|
rdbyte arg1, selectedWaveform3
|
|
shl arg1, #24
|
|
|
|
'───────────────────────────────────────────────────────────
|
|
' Envelope shaping channel 3 -> arg2
|
|
'───────────────────────────────────────────────────────────
|
|
Env_Attack3 cmp envelopeState3, #0 wz
|
|
if_nz jmp #InitDecay3
|
|
add envelopeLevel3, attack3 wc
|
|
if_c mov envelopeLevel3, mask32bit
|
|
if_c mov envelopeState3, #1
|
|
mov decayDivide3, #0
|
|
jmp #Amplitude3
|
|
'-----------------------------------------------------------
|
|
InitDecay3 mov tempValue, decayDivideRef
|
|
shr tempValue, decayDivide3
|
|
cmp envelopeLevel3, tempValue wc
|
|
if_c add decayDivide3, #1
|
|
'-----------------------------------------------------------
|
|
Env_Decay3 cmp envelopeState3, #1 wz
|
|
if_nz jmp #Env_Release3
|
|
shr decay3, decayDivide3
|
|
sub envelopeLevel3, decay3
|
|
min envelopeLevel3, sustain3 wc
|
|
jmp #Amplitude3
|
|
'-----------------------------------------------------------
|
|
Env_Release3 cmp envelopeState3, #2 wz
|
|
if_nz jmp #Amplitude3
|
|
shr release3, decayDivide3
|
|
cmpsub envelopeLevel3, release3
|
|
|
|
'───────────────────────────────────────────────────────────
|
|
'Calculate sample out3 = arg1 * arg2 (waveform * amplitude)
|
|
'───────────────────────────────────────────────────────────
|
|
Amplitude3 shr arg1, #16
|
|
sub arg1, val15bit
|
|
mov arg2, envelopeLevel3
|
|
shr arg2, #22
|
|
call #multiply
|
|
mov out3, r1
|
|
SID_ret ret
|
|
|
|
'
|
|
' Handle multi-mode filtering
|
|
'
|
|
filter mov ordinaryOutput, #0 '|
|
|
mov highPassFilter, #0 '|
|
|
test filterControl, #1 wc '|
|
|
if_c add highPassFilter, out1 '|
|
|
if_nc add ordinaryOutput, out1 '|
|
|
test filterControl, #2 wc '| Route channels trough the filter
|
|
if_c add highPassFilter, out2 '| or bypass them
|
|
if_nc add ordinaryOutput, out2 '|
|
|
test filterControl, #4 wc '|
|
|
if_c add highPassFilter, out3 '|
|
|
if_nc add ordinaryOutput, out3 '|
|
|
'-----------------------------------------------------------
|
|
mov tempValue, bandPassFilter '|
|
|
sar tempValue, filterResonance '| High pass filter
|
|
sub highPassFilter, tempValue '|
|
|
sub highPassFilter, lowPassFilter '|
|
|
'-----------------------------------------------------------
|
|
mov arg1, highPassFilter '|
|
|
sar arg1, #BP_MAX_CUTOFF '|
|
|
mov arg2, filterCutoff '| Band pass filter
|
|
max arg2, maxCutoff
|
|
call #multiplyNS '|
|
|
add bandPassFilter, r1 '|
|
|
'-----------------------------------------------------------
|
|
mov arg1, bandPassFilter '|
|
|
sar arg1, #LP_MAX_CUTOFF '|
|
|
mov arg2, filterCutoff '| Low pass filter
|
|
call #multiplyNS '|
|
|
add lowPassFilter, r1 '|
|
|
'-----------------------------------------------------------
|
|
mov filterOutput, #0 '|
|
|
test filterMode_Volume, #16 wc '|
|
|
if_c add filterOutput, lowPassFilter '|
|
|
test filterMode_Volume, #32 wc '| Enable/Disable
|
|
if_c add filterOutput, bandPassFilter '| Low/Band/High pass filtering
|
|
test filterMode_Volume, #64 wc '|
|
|
if_c add filterOutput, highPassFilter '|
|
|
filter_ret ret
|
|
|
|
'
|
|
' Mix channels and update FRQA/FRQB PWM-values
|
|
'
|
|
mixer mov arg1, filterOutput
|
|
add arg1, ordinaryOutput
|
|
'-----------------------------------------------------------
|
|
maxs arg1, clipLevelHigh '|
|
|
mins arg1, clipLevelLow '|
|
|
mov arg2, filterMode_Volume '| Main volume adjustment
|
|
and arg2, #15 '|
|
|
call #multiplyNS '|
|
|
'-----------------------------------------------------------
|
|
add r1, val31bit ' DC offset
|
|
waitcnt waitCounter, sampleRate ' Wait until the right time to update
|
|
mov FRQA, r1 '| Update PWM values in FRQA/FRQB
|
|
mov FRQB, r1 '|
|
|
mov tempValue, par
|
|
add tempValue, #28
|
|
wrlong r1, tempValue '| Write the sample to hub ram
|
|
mixer_ret ret
|
|
|
|
'
|
|
' Get attack value r1 = attackTable[arg1]
|
|
'
|
|
getAttack mov arg2, arg1
|
|
and arg1, #15
|
|
add arg1, #ADSRTable
|
|
movs :indexed1, arg1
|
|
mov arg1, arg2
|
|
:indexed1 mov r1, 0
|
|
getAttack_ret ret
|
|
|
|
'
|
|
' Get decay value r1 = decayTable[arg1]
|
|
'
|
|
getDecay mov arg2, arg1
|
|
and arg1, #15
|
|
add arg1, #ADSRTable
|
|
movs :indexed2, arg1
|
|
mov arg1, arg2
|
|
:indexed2 mov r1, 0
|
|
getDecay_ret ret
|
|
|
|
'
|
|
' Multiplication r1(I32) = arg1(I32) * arg2(I32)
|
|
'
|
|
multiply cmp arg1, arg2 wc 'If arg1 is less than arg2 C is set
|
|
if_c xor arg1, arg2 'Swap arguments
|
|
if_c xor arg2, arg1
|
|
if_c xor arg1, arg2
|
|
multiplyNS mov r1, #0 'Clear 32-bit product
|
|
:multiLoop shr arg2, #1 wc, wz 'Half multiplyer and get LSB of it
|
|
if_c add r1, arg1 'Add multiplicand to product on C
|
|
shl arg1, #1 'Double multiplicand
|
|
if_nz jmp #:multiLoop 'Check nonzero multiplier to continue multiplication
|
|
multiplyNS_ret
|
|
multiply_ret ret
|
|
|
|
'
|
|
' Variables, tables, masks and reference values
|
|
'
|
|
|
|
ADSRTable long 68719476 '2 ms
|
|
long 17179870 '8 ms
|
|
long 8589934 '16 ms
|
|
long 5726622 '24 ms
|
|
long 3616814 '38 ms
|
|
long 2454268 '56 ms
|
|
long 2021160 '68 ms
|
|
long 1717986 '80 ms
|
|
long 1374390 '100 ms
|
|
long 549754 '250 ms
|
|
long 274876 '500 ms
|
|
long 171798 '800 ms
|
|
long 137438 '1 s
|
|
long 45812 '3 s
|
|
long 27486 '5 s
|
|
long 17180 '8 s
|
|
|
|
resTable long 0,1,1,1,1,1,2,2 '(Ariba)
|
|
|
|
'Masks and reference values
|
|
mask32bit long $ffffffff
|
|
mask31bit long $7fffffff
|
|
mask28bit long $fffffff
|
|
mask24bit long $ffffff
|
|
mask20bit long $fffff
|
|
mask16bit long $ffff
|
|
mask11bit long $7ff
|
|
val31bit long $80000000
|
|
val28bit long $10000000
|
|
val27bit long $8000000
|
|
val16bit long $10000
|
|
val15bit long $8000
|
|
clipLevelHigh long $8000000
|
|
clipLevelLow long-$8000000
|
|
noiseAdd long NOISE_ADD 'Value to add to the noise generator every noise update
|
|
filterOffset long FILTER_OFFSET
|
|
decayDivideRef long DECAY_DIVIDE_REF
|
|
maxCutoff long CUTOFF_LIMIT
|
|
sampleRate long 0 'clocks between samples ( ~31.250 khz )
|
|
combTableAddr long 0
|
|
|
|
'Setup and subroutine parameters
|
|
arg1 long 1
|
|
arg2 long 1
|
|
r1 long 1
|
|
|
|
'Sid variables
|
|
envelopeLevel1 long 1
|
|
envelopeLevel2 long 1
|
|
envelopeLevel3 long 1
|
|
controlRegister1 res 1
|
|
controlRegister2 res 1
|
|
controlRegister3 res 1
|
|
frequency1 res 1
|
|
frequency2 res 1
|
|
frequency3 res 1
|
|
phaseAccumulator1 res 1
|
|
phaseAccumulator2 res 1
|
|
phaseAccumulator3 res 1
|
|
pulseWidth1 res 1
|
|
pulseWidth2 res 1
|
|
pulseWidth3 res 1
|
|
selectedWaveform1 res 1
|
|
selectedWaveform2 res 1
|
|
selectedWaveform3 res 1
|
|
envelopeState1 res 1
|
|
envelopeState2 res 1
|
|
envelopeState3 res 1
|
|
noiseValue1 res 1
|
|
noiseValue2 res 1
|
|
noiseValue3 res 1
|
|
attack1 res 1
|
|
attack2 res 1
|
|
attack3 res 1
|
|
decay1 res 1
|
|
decay2 res 1
|
|
decay3 res 1
|
|
sustain1 res 1
|
|
sustain2 res 1
|
|
sustain3 res 1
|
|
release1 res 1
|
|
release2 res 1
|
|
release3 res 1
|
|
decayDivide1 res 1
|
|
decayDivide2 res 1
|
|
decayDivide3 res 1
|
|
out1 res 1
|
|
out2 res 1
|
|
out3 res 1
|
|
filterResonance res 1
|
|
filterCutoff res 1
|
|
highPassFilter res 1
|
|
bandPassFilter res 1
|
|
lowPassFilter res 1
|
|
filterMode_Volume res 1
|
|
filterControl res 1
|
|
filterOutput res 1
|
|
ordinaryOutput res 1
|
|
|
|
'Working variables
|
|
waitCounter res 1
|
|
tempValue res 1
|
|
fit
|
|
|
|
dat
|
|
combinedWaveforms file "CombinedWaveforms.bin"
|
|
|
|
VAR
|
|
byte ch1_frequencyLo
|
|
byte ch1_frequencyHi
|
|
byte ch1_pulseWidthLo
|
|
byte ch1_pulseWidthHi
|
|
byte ch1_controlRegister
|
|
byte ch1_attackDecay
|
|
byte ch1_sustainRelease
|
|
byte ch1_dummy
|
|
byte ch2_frequencyLo
|
|
byte ch2_frequencyHi
|
|
byte ch2_pulseWidthLo
|
|
byte ch2_pulseWidthHi
|
|
byte ch2_controlRegister
|
|
byte ch2_attackDecay
|
|
byte ch2_sustainRelease
|
|
byte ch2_dummy
|
|
byte ch3_frequencyLo
|
|
byte ch3_frequencyHi
|
|
byte ch3_pulseWidthLo
|
|
byte ch3_pulseWidthHi
|
|
byte ch3_controlRegister
|
|
byte ch3_attackDecay
|
|
byte ch3_sustainRelease
|
|
byte ch3_dummy
|
|
byte Filter1
|
|
byte Filter2
|
|
byte Filter3
|
|
byte Volume
|
|
long SIDSample
|
|
byte cog
|
|
|