PWM LFO working
This commit is contained in:
Gordon JC Pearce
parent
1f6188f751
commit
1d4e6ab2bd
@ -121,6 +121,7 @@ void Chassis::run(const float **, float **outputs, uint32_t frames, const MidiEv
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doMidi(midiEvents, midiEventCount, framePos + s.blockLeft);
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// printf("compute params and reset block size\n");
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s.runLFO();
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for (uint32_t i = 0; i < NUM_VOICES; i++) {
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s.voice[i].gate(s);
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@ -1,14 +1,34 @@
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#include "voice.hpp"
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/*
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Chassis polysynth framework
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Copyright 2024 Gordon JC Pearce <gordonjcp@gjcp.net>
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Permission to use, copy, modify, and/or distribute this software for any
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purpose with or without fee is hereby granted, provided that the above
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copyright notice and this permission notice appear in all copies.
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THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
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WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
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MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
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SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
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WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
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OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
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CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
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*/
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// contains the emulation of the digital bits
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#include <cmath>
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#include <cstdio>
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#include "voice.hpp"
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bool Voice::isFree() {
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return ff10 == false;
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}
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void Voice::on(uint32_t key, bool reset = 0) {
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// printf("======================================================================================\n");
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// what's with the crazy private variables and all the gotos with crazy labels?
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// this code emulates the 78C11 code directly (probably inefficiently)
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// to allow for documenting what the variables actually do
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@ -35,8 +55,6 @@ h0144:
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if (!ff11) goto h0132; // unsure, copied from ff10 at start of mainloop
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h0149:
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// printf("after 0144h, %d %x %x %x %x\n", note, ff07, ff10, ff11, ff33);
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// this is in the wrong place really but is the equivalent of programming the counter
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// and VCO ramp DAC
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omega = (261.63 * powf(2, (note - 60) / 12.0f)) / 48000.0f;
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@ -48,12 +66,8 @@ void Voice::off() {
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if (!sustain) { // dummy sustain
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ff33 = false;
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}
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// printf("after note off, %d %x %x %x %x\n", note, ff07, ff10, ff11, ff33);
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}
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void Voice::gate(Synth &s) {
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uint16_t bc, ea = env;
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@ -113,3 +127,60 @@ h0590:
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env = ea;
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// printf("%04x %d %d %d %d %d \n", ea, ff07, ff08, ff10, ff11, ff33);
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}
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void Synth::runLFO() {
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// compute a loop's worth of LFO
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uint16_t a, b, c, d;
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uint16_t bc, hl, ea, tos;
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// 074e
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ea = ff4d; // lfo value
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bc = lfoRateTable[patchRam.lfoRate];
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if (!(ff4a & 0x01)) goto h078b;
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ea -= bc;
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if (ea < bc) goto h079a;
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h075f:
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ff4d = ea;
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if (!(ff4a & 0x02)) goto h07a2;
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// 0765
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bc = ea;
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ea = 0x2000;
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ea -= bc;
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h076b:
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bc = ea;
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if (patchRam.switch2 & 0x01) {
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bc = 0x3fff;
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}
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bc = (bc * patchRam.pwmLfo) >> 7;
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bc = 0x3fff - bc;
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if (!(patchRam.switch1 & 0x08)) bc = 0x0000; // square off
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ff4f = bc;
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// 078a
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goto h07a9;
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h078b:
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ea += bc;
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if (ea & 0xe000) {
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ea = 0x1fff;
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ff4a++;
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}
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goto h075f;
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h079a:
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ea = 0;
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ff4a++;
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goto h075f;
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h07a2:
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ea += 0x2000;
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goto h076b;
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h07a9:
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return;
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}
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@ -265,7 +265,7 @@ void Chassis::setParameterValue(uint32_t index, float value) {
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s.patchRam.vcoLfo = value;
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break;
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case paramPWMLFO:
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s.patchRam.pwmLfo = value;
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s.patchRam.pwmLfo = value/1.27;
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break;
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case paramSub:
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s.patchRam.sub = value;
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@ -16,13 +16,12 @@
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CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
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*/
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// contains the actual sound generation code
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#include "voice.hpp"
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#include <math.h>
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#include <cstdio>
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#include <math.h>
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static inline float poly3blep0(float t) {
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float t2 = t * t;
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@ -39,15 +38,16 @@ void Voice::run(Synth &s, float *buffer, uint32_t samples) {
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// 325, because it needs PW to be from 0 to 0.5
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// but really the control range is limited from 0 to 100
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// there's a resistor on the panel board to sprag the range
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float pw = 0.5 - s.patchRam.pwmLfo/325.0f;
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float pw = s.ff4f / 32768.0f;
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float sqr = (s.patchRam.switch1 & 0x08) ? 0.175 : 0;
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float sqr = 0.175;
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float saw = (s.patchRam.switch1 & 0x10) ? 0.220 : 0;
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float sub = (s.patchRam.sub / 127.0f) * 0.275;
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float gain = 0.5 * powf(2, (s.patchRam.vca / 64.0f) - 1);
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float vcaEnv = (s.patchRam.switch2 & 0x04)?(float)ff11:(env / 16384.0f);
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float vcaEnv = (s.patchRam.switch2 & 0x04) ? (float)ff11 : (env / 16384.0f);
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for (uint32_t i = 0; i < samples; i++) {
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y = delay;
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@ -61,10 +61,10 @@ void Voice::run(Synth &s, float *buffer, uint32_t samples) {
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while (true) {
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if (pulseStage == 0) {
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if (phase < pw) break;
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#if 1
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#if 0
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t = (phase - pw) / omega;
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#else
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t = (phase - pw) / (widthDelay - pw + freq);
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t = (phase - pw) / (lastpw - pw + omega);
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#endif
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y -= poly3blep0(t) * sqr;
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delay -= poly3blep1(t) * sqr;
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@ -97,7 +97,8 @@ void Voice::run(Synth &s, float *buffer, uint32_t samples) {
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out = y;
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// widthDelay = pw;
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vr58c106 += ((vcaEnv- vr58c106) * 0.0075);
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vr58c106 += ((vcaEnv - vr58c106) * 0.0075);
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lastpw = pw;
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buffer[i] += (gain * out * vr58c106);
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}
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}
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123
plugin/voice.hpp
123
plugin/voice.hpp
@ -24,12 +24,6 @@
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class Synth;
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class Patch {
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public:
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float saw, sqr, sub;
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uint16_t attack, decay, sustain, release;
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};
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class Voice {
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public:
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// uint8_t note = 72;
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@ -55,11 +49,11 @@ class Voice {
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K_ON,
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K_SUSTAIN } keyState = K_OFF;
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bool ff00 = 0; // reset bit
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bool ff07 = 0; // status bit
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bool ff08 = 0; // set to indicate attack phase complete
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bool ff00 = 0; // reset DCO clock flag
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bool ff07 = 0; // set to indicate attack phase
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bool ff08 = 0; // set to indicate decay/sustain phase
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bool ff10 = 0; // note on bit
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bool ff11 = 0; // sustain flag
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bool ff11 = 0; // drives the "gate" signal for VCA
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bool ff33 = 0; // releasing flag
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uint16_t env;
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@ -69,52 +63,60 @@ class Voice {
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float delay;
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uint8_t pulseStage = 0;
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float pw_rc = 0;
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float lastpw = 0;
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float vr58c106 = 0;
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uint16_t attack_table[128] = {
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0x4000, 0x2000, 0x1000, 0x0aaa, 0x0800, 0x0666, 0x0555, 0x0492, 0x0400,
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0x038e, 0x0333, 0x02e9, 0x02ab, 0x0276, 0x0249, 0x0222, 0x0200, 0x01e2,
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0x01c7, 0x01af, 0x0199, 0x0186, 0x0174, 0x0164, 0x0155, 0x0148, 0x013b,
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0x012f, 0x0124, 0x011a, 0x0111, 0x0108, 0x0100, 0x00f8, 0x00f1, 0x00ea,
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0x00e4, 0x00dd, 0x00d8, 0x00d2, 0x00cd, 0x00c8, 0x00c3, 0x00bf, 0x00ba,
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0x00b6, 0x00b2, 0x00ae, 0x00ab, 0x00a7, 0x00a4, 0x00a1, 0x009e, 0x009b,
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0x0098, 0x0095, 0x0092, 0x0090, 0x008d, 0x008b, 0x0089, 0x0086, 0x0084,
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0x0082, 0x007f, 0x007d, 0x007a, 0x0077, 0x0074, 0x0072, 0x006f, 0x006c,
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0x0069, 0x0067, 0x0064, 0x0061, 0x005e, 0x005c, 0x0059, 0x0056, 0x0053,
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0x0050, 0x004e, 0x004b, 0x0048, 0x0045, 0x0042, 0x0040, 0x003f, 0x003d,
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0x003c, 0x003a, 0x0039, 0x0037, 0x0036, 0x0034, 0x0033, 0x0031, 0x0030,
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0x002e, 0x002d, 0x002b, 0x002a, 0x0028, 0x0027, 0x0025, 0x0024, 0x0022,
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0x0021, 0x0021, 0x0020, 0x0020, 0x001f, 0x001f, 0x001e, 0x001e, 0x001d,
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0x001d, 0x001c, 0x001c, 0x001b, 0x001b, 0x001a, 0x0019, 0x0018, 0x0017,
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0x0016, 0x0015};
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0x4000, 0x2000, 0x1000, 0x0aaa, 0x0800, 0x0666, 0x0555, 0x0492, 0x0400,
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0x038e, 0x0333, 0x02e9, 0x02ab, 0x0276, 0x0249, 0x0222, 0x0200, 0x01e2,
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0x01c7, 0x01af, 0x0199, 0x0186, 0x0174, 0x0164, 0x0155, 0x0148, 0x013b,
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0x012f, 0x0124, 0x011a, 0x0111, 0x0108, 0x0100, 0x00f8, 0x00f1, 0x00ea,
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0x00e4, 0x00dd, 0x00d8, 0x00d2, 0x00cd, 0x00c8, 0x00c3, 0x00bf, 0x00ba,
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0x00b6, 0x00b2, 0x00ae, 0x00ab, 0x00a7, 0x00a4, 0x00a1, 0x009e, 0x009b,
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0x0098, 0x0095, 0x0092, 0x0090, 0x008d, 0x008b, 0x0089, 0x0086, 0x0084,
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0x0082, 0x007f, 0x007d, 0x007a, 0x0077, 0x0074, 0x0072, 0x006f, 0x006c,
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0x0069, 0x0067, 0x0064, 0x0061, 0x005e, 0x005c, 0x0059, 0x0056, 0x0053,
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0x0050, 0x004e, 0x004b, 0x0048, 0x0045, 0x0042, 0x0040, 0x003f, 0x003d,
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0x003c, 0x003a, 0x0039, 0x0037, 0x0036, 0x0034, 0x0033, 0x0031, 0x0030,
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0x002e, 0x002d, 0x002b, 0x002a, 0x0028, 0x0027, 0x0025, 0x0024, 0x0022,
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0x0021, 0x0021, 0x0020, 0x0020, 0x001f, 0x001f, 0x001e, 0x001e, 0x001d,
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0x001d, 0x001c, 0x001c, 0x001b, 0x001b, 0x001a, 0x0019, 0x0018, 0x0017,
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0x0016, 0x0015};
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uint16_t decay_table[128] = {
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0x1000, 0x3000, 0x5000, 0x7000, 0x9000, 0xa000, 0xa800, 0xb000, 0xb800,
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0xc000, 0xc800, 0xd000, 0xd800, 0xe000, 0xe800, 0xf000, 0xf080, 0xf100,
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0xf180, 0xf200, 0xf280, 0xf300, 0xf380, 0xf400, 0xf480, 0xf500, 0xf580,
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0xf600, 0xf680, 0xf700, 0xf780, 0xf800, 0xf880, 0xf900, 0xf980, 0xfa00,
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0xfa80, 0xfb00, 0xfb80, 0xfc00, 0xfc80, 0xfd00, 0xfd80, 0xfe00, 0xfe0c,
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0xfe18, 0xfe24, 0xfe30, 0xfe3c, 0xfe48, 0xfe54, 0xfe60, 0xfe6c, 0xfe78,
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0xfe84, 0xfe90, 0xfe9c, 0xfea8, 0xfeb4, 0xfec0, 0xfecc, 0xfed8, 0xfee4,
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0xfef0, 0xfefc, 0xff08, 0xff0c, 0xff10, 0xff14, 0xff18, 0xff1c, 0xff20,
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0xff24, 0xff28, 0xff2c, 0xff30, 0xff34, 0xff38, 0xff3c, 0xff40, 0xff44,
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0xff48, 0xff4c, 0xff50, 0xff54, 0xff58, 0xff5c, 0xff60, 0xff64, 0xff68,
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0xff6c, 0xff70, 0xff74, 0xff78, 0xff7c, 0xff80, 0xff84, 0xff88, 0xff8c,
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0xff90, 0xff94, 0xff98, 0xff9c, 0xffa0, 0xffa4, 0xffa8, 0xffac, 0xffb0,
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0xffb4, 0xffb8, 0xffbc, 0xffc0, 0xffc4, 0xffc8, 0xffcc, 0xffd0, 0xffd4,
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0xffd8, 0xffdc, 0xffe0, 0xffe4, 0xffe8, 0xffec, 0xfff0, 0xfff1, 0xfff2,
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0xfff3, 0xfff4};
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uint16_t decay_table[128] = {
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0x1000, 0x3000, 0x5000, 0x7000, 0x9000, 0xa000, 0xa800, 0xb000, 0xb800,
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0xc000, 0xc800, 0xd000, 0xd800, 0xe000, 0xe800, 0xf000, 0xf080, 0xf100,
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0xf180, 0xf200, 0xf280, 0xf300, 0xf380, 0xf400, 0xf480, 0xf500, 0xf580,
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0xf600, 0xf680, 0xf700, 0xf780, 0xf800, 0xf880, 0xf900, 0xf980, 0xfa00,
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0xfa80, 0xfb00, 0xfb80, 0xfc00, 0xfc80, 0xfd00, 0xfd80, 0xfe00, 0xfe0c,
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0xfe18, 0xfe24, 0xfe30, 0xfe3c, 0xfe48, 0xfe54, 0xfe60, 0xfe6c, 0xfe78,
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0xfe84, 0xfe90, 0xfe9c, 0xfea8, 0xfeb4, 0xfec0, 0xfecc, 0xfed8, 0xfee4,
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0xfef0, 0xfefc, 0xff08, 0xff0c, 0xff10, 0xff14, 0xff18, 0xff1c, 0xff20,
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0xff24, 0xff28, 0xff2c, 0xff30, 0xff34, 0xff38, 0xff3c, 0xff40, 0xff44,
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0xff48, 0xff4c, 0xff50, 0xff54, 0xff58, 0xff5c, 0xff60, 0xff64, 0xff68,
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0xff6c, 0xff70, 0xff74, 0xff78, 0xff7c, 0xff80, 0xff84, 0xff88, 0xff8c,
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0xff90, 0xff94, 0xff98, 0xff9c, 0xffa0, 0xffa4, 0xffa8, 0xffac, 0xffb0,
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0xffb4, 0xffb8, 0xffbc, 0xffc0, 0xffc4, 0xffc8, 0xffcc, 0xffd0, 0xffd4,
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0xffd8, 0xffdc, 0xffe0, 0xffe4, 0xffe8, 0xffec, 0xfff0, 0xfff1, 0xfff2,
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0xfff3, 0xfff4};
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};
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class Synth {
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public:
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Patch patch;
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Voice voice[8];
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float lfo = 0, lfosw = 0.01;
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float lastpw = 0;
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uint32_t blockLeft;
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uint32_t framesLeft = 0;
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uint8_t ff1e;
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uint8_t ff4a; // LFO flags
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uint16_t ff4d = 0; // LFO output value
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uint16_t ff4f; // computed PWM LFO
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uint16_t ff51; // computed pitch LFO
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uint16_t ff53; // computed VCF LFO
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uint16_t ff56; // LFO Delay envelope
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uint16_t ff5a; // LFO Delay holdoff
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uint8_t ff64; // LFO mod sens amount
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// okay, not the greatest, this right here
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// this struct contains the bytes that make up a Juno 106 patch in
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// sysex order, exactly as they'd be transmitted or received by a
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@ -142,6 +144,35 @@ class Synth {
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uint8_t switch1 = 26;
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uint8_t switch2 = 24;
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} patchRam;
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uint8_t lfoDepthTable[128] = {
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0x00, 0x00, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09,
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0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15,
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0x16, 0x17, 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 0x20, 0x21,
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0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d,
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0x2e, 0x2f, 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39,
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0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x40, 0x42, 0x44, 0x46, 0x48, 0x4a, 0x4c,
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0x4e, 0x50, 0x52, 0x54, 0x56, 0x58, 0x5a, 0x5c, 0x5e, 0x60, 0x62, 0x64,
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0x66, 0x68, 0x6a, 0x6c, 0x6e, 0x70, 0x72, 0x74, 0x76, 0x78, 0x7a, 0x7c,
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0x80, 0x84, 0x88, 0x8c, 0x90, 0x94, 0x98, 0x9c, 0xa0, 0xa4, 0xa8, 0xac,
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0xb0, 0xb4, 0xb8, 0xbc, 0xc0, 0xc4, 0xc8, 0xcc, 0xd0, 0xd4, 0xd8, 0xdc,
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0xe0, 0xe4, 0xe8, 0xec, 0xf0, 0xf8, 0xff, 0xff};
|
||||
uint16_t lfoRateTable[128] = {
|
||||
0x0005, 0x000f, 0x0019, 0x0028, 0x0037, 0x0046, 0x0050, 0x005a, 0x0064,
|
||||
0x006e, 0x0078, 0x0082, 0x008c, 0x0096, 0x00a0, 0x00aa, 0x00b4, 0x00be,
|
||||
0x00c8, 0x00d2, 0x00dc, 0x00e6, 0x00f0, 0x00fa, 0x0104, 0x010e, 0x0118,
|
||||
0x0122, 0x012c, 0x0136, 0x0140, 0x014a, 0x0154, 0x015e, 0x0168, 0x0172,
|
||||
0x017c, 0x0186, 0x0190, 0x019a, 0x01a4, 0x01ae, 0x01b8, 0x01c2, 0x01cc,
|
||||
0x01d6, 0x01e0, 0x01ea, 0x01f4, 0x01fe, 0x0208, 0x0212, 0x021c, 0x0226,
|
||||
0x0230, 0x023a, 0x0244, 0x024e, 0x0258, 0x0262, 0x026c, 0x0276, 0x0280,
|
||||
0x028a, 0x029a, 0x02aa, 0x02ba, 0x02ca, 0x02da, 0x02ea, 0x02fa, 0x030a,
|
||||
0x031a, 0x032a, 0x033a, 0x034a, 0x035a, 0x036a, 0x037a, 0x038a, 0x039a,
|
||||
0x03aa, 0x03ba, 0x03ca, 0x03da, 0x03ea, 0x03fa, 0x040a, 0x041a, 0x042a,
|
||||
0x043a, 0x044a, 0x045a, 0x046a, 0x047a, 0x048a, 0x04be, 0x04f2, 0x0526,
|
||||
0x055a, 0x058e, 0x05c2, 0x05f6, 0x062c, 0x0672, 0x06b8, 0x0708, 0x0758,
|
||||
0x07a8, 0x07f8, 0x085c, 0x08c0, 0x0924, 0x0988, 0x09ec, 0x0a50, 0x0ab4,
|
||||
0x0b18, 0x0b7c, 0x0be0, 0x0c58, 0x0cd0, 0x0d48, 0x0dde, 0x0e74, 0x0f0a,
|
||||
0x0fa0, 0x1000};
|
||||
|
||||
void runLFO();
|
||||
};
|
||||
|
||||
|
||||
|
||||
Loading…
Reference in New Issue
Block a user