furnace/src/engine/platform/sms.cpp
2022-04-15 15:01:11 -05:00

372 lines
10 KiB
C++

/**
* Furnace Tracker - multi-system chiptune tracker
* Copyright (C) 2021-2022 tildearrow and contributors
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "sms.h"
#include "../engine.h"
#include <math.h>
#define rWrite(v) {if (!skipRegisterWrites) {sn->write(v); if (dumpWrites) {addWrite(0x200,v);}}}
#define CHIP_DIVIDER 64
const char* regCheatSheetSN[]={
"DATA", "0",
NULL
};
const char** DivPlatformSMS::getRegisterSheet() {
return regCheatSheetSN;
}
const char* DivPlatformSMS::getEffectName(unsigned char effect) {
switch (effect) {
case 0x20:
return "20xy: Set noise mode (x: preset freq/ch3 freq; y: thin pulse/noise)";
break;
}
return NULL;
}
void DivPlatformSMS::acquire(short* bufL, short* bufR, size_t start, size_t len) {
sn->sound_stream_update(bufL+start,len);
}
int DivPlatformSMS::acquireOne() {
short v;
sn->sound_stream_update(&v,1);
return v;
}
void DivPlatformSMS::tick(bool sysTick) {
for (int i=0; i<4; i++) {
chan[i].std.next();
if (chan[i].std.vol.had) {
chan[i].outVol=MIN(15,chan[i].std.vol.val)-(15-(chan[i].vol&15));
if (chan[i].outVol<0) chan[i].outVol=0;
// old formula
// ((chan[i].vol&15)*MIN(15,chan[i].std.vol.val))>>4;
rWrite(0x90|(i<<5)|(isMuted[i]?15:(15-(chan[i].outVol&15))));
}
if (chan[i].std.arp.had) {
if (!chan[i].inPorta) {
if (chan[i].std.arp.mode) {
chan[i].baseFreq=NOTE_PERIODIC(chan[i].std.arp.val);
chan[i].actualNote=chan[i].std.arp.val;
} else {
// TODO: check whether this weird octave boundary thing applies to other systems as well
int areYouSerious=chan[i].note+chan[i].std.arp.val;
while (areYouSerious>0x60) areYouSerious-=12;
chan[i].baseFreq=NOTE_PERIODIC(areYouSerious);
chan[i].actualNote=areYouSerious;
}
chan[i].freqChanged=true;
}
} else {
if (chan[i].std.arp.mode && chan[i].std.arp.finished) {
chan[i].baseFreq=NOTE_PERIODIC(chan[i].note);
chan[i].actualNote=chan[i].note;
chan[i].freqChanged=true;
}
}
if (i==3) {
if (chan[i].std.duty.had) {
snNoiseMode=chan[i].std.duty.val;
if (chan[i].std.duty.val<2) {
chan[3].freqChanged=false;
}
updateSNMode=true;
}
if (chan[i].std.phaseReset.had) {
if (chan[i].std.phaseReset.val==1) {
updateSNMode=true;
}
}
}
}
for (int i=0; i<3; i++) {
if (chan[i].freqChanged) {
chan[i].freq=parent->calcFreq(chan[i].baseFreq,chan[i].pitch,true)+chan[i].std.pitch.val;
if (chan[i].freq>1023) chan[i].freq=1023;
if (chan[i].freq<8) chan[i].freq=1;
//if (chan[i].actualNote>0x5d) chan[i].freq=0x01;
rWrite(0x80|i<<5|(chan[i].freq&15));
rWrite(chan[i].freq>>4);
// what?
/*if (i==2 && snNoiseMode&2) {
chan[3].baseFreq=chan[2].baseFreq;
chan[3].actualNote=chan[2].actualNote;
}*/
chan[i].freqChanged=false;
}
}
if (chan[3].freqChanged || updateSNMode) {
// seems arbitrary huh?
chan[3].freq=parent->calcFreq(chan[3].baseFreq,chan[3].pitch-1-(isRealSN?127:0),true)+chan[3].std.pitch.val;
if (chan[3].freq>1023) chan[3].freq=1023;
if (chan[3].actualNote>0x5d) chan[3].freq=0x01;
if (snNoiseMode&2) { // take period from channel 3
if (updateSNMode || resetPhase) {
if (snNoiseMode&1) {
rWrite(0xe7);
} else {
rWrite(0xe3);
}
if (updateSNMode) {
rWrite(0xdf);
}
}
if (chan[3].freqChanged) {
rWrite(0xc0|(chan[3].freq&15));
rWrite(chan[3].freq>>4);
}
} else { // 3 fixed values
unsigned char value;
if (chan[3].std.arp.had) {
if (chan[3].std.arp.mode) {
value=chan[3].std.arp.val%12;
} else {
value=(chan[3].note+chan[3].std.arp.val)%12;
}
} else {
value=chan[3].note%12;
}
if (value<3) {
value=2-value;
if (value!=oldValue || updateSNMode || resetPhase) {
oldValue=value;
rWrite(0xe0|value|((snNoiseMode&1)<<2));
}
}
}
chan[3].freqChanged=false;
updateSNMode=false;
}
}
int DivPlatformSMS::dispatch(DivCommand c) {
switch (c.cmd) {
case DIV_CMD_NOTE_ON:
if (c.value!=DIV_NOTE_NULL) {
chan[c.chan].baseFreq=NOTE_PERIODIC(c.value);
chan[c.chan].freqChanged=true;
chan[c.chan].note=c.value;
chan[c.chan].actualNote=c.value;
}
chan[c.chan].active=true;
rWrite(0x90|c.chan<<5|(isMuted[c.chan]?15:(15-(chan[c.chan].vol&15))));
chan[c.chan].std.init(parent->getIns(chan[c.chan].ins));
break;
case DIV_CMD_NOTE_OFF:
chan[c.chan].active=false;
rWrite(0x9f|c.chan<<5);
chan[c.chan].std.init(NULL);
break;
case DIV_CMD_NOTE_OFF_ENV:
case DIV_CMD_ENV_RELEASE:
chan[c.chan].std.release();
break;
case DIV_CMD_INSTRUMENT:
chan[c.chan].ins=c.value;
//chan[c.chan].std.init(parent->getIns(chan[c.chan].ins));
break;
case DIV_CMD_VOLUME:
if (chan[c.chan].vol!=c.value) {
chan[c.chan].vol=c.value;
if (!chan[c.chan].std.vol.has) {
chan[c.chan].outVol=c.value;
}
if (chan[c.chan].active) rWrite(0x90|c.chan<<5|(isMuted[c.chan]?15:(15-(chan[c.chan].vol&15))));
}
break;
case DIV_CMD_GET_VOLUME:
if (chan[c.chan].std.vol.has) {
return chan[c.chan].vol;
}
return chan[c.chan].outVol;
break;
case DIV_CMD_PITCH:
chan[c.chan].pitch=c.value;
chan[c.chan].freqChanged=true;
break;
case DIV_CMD_NOTE_PORTA: {
int destFreq=NOTE_PERIODIC(c.value2);
bool return2=false;
if (destFreq>chan[c.chan].baseFreq) {
chan[c.chan].baseFreq+=c.value;
if (chan[c.chan].baseFreq>=destFreq) {
chan[c.chan].baseFreq=destFreq;
return2=true;
}
} else {
chan[c.chan].baseFreq-=c.value;
if (chan[c.chan].baseFreq<=destFreq) {
chan[c.chan].baseFreq=destFreq;
return2=true;
}
}
chan[c.chan].freqChanged=true;
if (return2) {
chan[c.chan].inPorta=false;
return 2;
}
break;
}
case DIV_CMD_STD_NOISE_MODE:
snNoiseMode=(c.value&1)|((c.value&16)>>3);
updateSNMode=true;
break;
case DIV_CMD_LEGATO:
chan[c.chan].baseFreq=NOTE_PERIODIC(c.value+((chan[c.chan].std.arp.will && !chan[c.chan].std.arp.mode)?(chan[c.chan].std.arp.val):(0)));
chan[c.chan].freqChanged=true;
chan[c.chan].note=c.value;
chan[c.chan].actualNote=c.value;
break;
case DIV_CMD_PRE_PORTA:
if (chan[c.chan].active && c.value2) {
if (parent->song.resetMacroOnPorta) chan[c.chan].std.init(parent->getIns(chan[c.chan].ins));
}
chan[c.chan].inPorta=c.value;
break;
case DIV_CMD_GET_VOLMAX:
return 15;
break;
case DIV_ALWAYS_SET_VOLUME:
return 0;
break;
default:
break;
}
return 1;
}
void DivPlatformSMS::muteChannel(int ch, bool mute) {
isMuted[ch]=mute;
if (chan[ch].active) rWrite(0x90|ch<<5|(isMuted[ch]?15:(15-(chan[ch].outVol&15))));
}
void DivPlatformSMS::forceIns() {
for (int i=0; i<4; i++) {
if (chan[i].active) {
chan[i].insChanged=true;
chan[i].freqChanged=true;
}
}
updateSNMode=true;
}
void* DivPlatformSMS::getChanState(int ch) {
return &chan[ch];
}
void DivPlatformSMS::reset() {
for (int i=0; i<4; i++) {
chan[i]=DivPlatformSMS::Channel();
chan[i].std.setEngine(parent);
}
if (dumpWrites) {
addWrite(0xffffffff,0);
}
sn->device_start();
snNoiseMode=3;
rWrite(0xe7);
updateSNMode=false;
oldValue=0xff;
}
bool DivPlatformSMS::keyOffAffectsArp(int ch) {
return true;
}
bool DivPlatformSMS::keyOffAffectsPorta(int ch) {
return true;
}
int DivPlatformSMS::getPortaFloor(int ch) {
return 12;
}
void DivPlatformSMS::notifyInsDeletion(void* ins) {
for (int i=0; i<4; i++) {
chan[i].std.notifyInsDeletion((DivInstrument*)ins);
}
}
void DivPlatformSMS::poke(unsigned int addr, unsigned short val) {
rWrite(val);
}
void DivPlatformSMS::poke(std::vector<DivRegWrite>& wlist) {
for (DivRegWrite& i: wlist) rWrite(i.val);
}
void DivPlatformSMS::setFlags(unsigned int flags) {
if ((flags&3)==3) {
chipClock=COLOR_NTSC/2.0;
} else if ((flags&3)==2) {
chipClock=4000000;
} else if ((flags&3)==1) {
chipClock=COLOR_PAL*4.0/5.0;
} else {
chipClock=COLOR_NTSC;
}
resetPhase=!(flags&16);
if (sn!=NULL) delete sn;
switch ((flags>>2)&3) {
case 1: // TI
sn=new sn76496_base_device(0x4000, 0x4000, 0x01, 0x02, true, 1, false, true);
isRealSN=true;
break;
case 2: // TI+Atari
sn=new sn76496_base_device(0x4000, 0x0f35, 0x01, 0x02, true, 1, false, true);
isRealSN=true;
break;
case 3: // Game Gear (not fully emulated yet!)
sn=new sn76496_base_device(0x8000, 0x8000, 0x01, 0x08, false, 1, false, false);
isRealSN=false;
break;
default: // Sega
sn=new sn76496_base_device(0x8000, 0x8000, 0x01, 0x08, false, 1, false, false);
isRealSN=false;
break;
}
rate=chipClock/16;
}
int DivPlatformSMS::init(DivEngine* p, int channels, int sugRate, unsigned int flags) {
parent=p;
dumpWrites=false;
skipRegisterWrites=false;
resetPhase=false;
oldValue=0xff;
for (int i=0; i<4; i++) {
isMuted[i]=false;
}
sn=NULL;
setFlags(flags);
reset();
return 4;
}
void DivPlatformSMS::quit() {
if (sn!=NULL) delete sn;
}
DivPlatformSMS::~DivPlatformSMS() {
}