forked from bfirsh/jsnes
/
mappers.js
1150 lines (859 loc) · 29.4 KB
/
mappers.js
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function MapperDefault(nes) {
this.nes = nes;
this.joy1StrobeState = null;
this.joy2StrobeState = null;
this.joypadLastWrite = -1;
this.mousePressed = null;
this.gameGenieActive = null;
this.mouseX = null;
this.mouseY = null;
this.tmp = null;
}
MapperDefault.prototype.write = function(address, value){
if(address<0x2000){
// Mirroring of RAM:
this.nes.cpuMem[address & 0x7FF] = value;
}else if(address>0x4017){
this.nes.cpuMem[address] = value;
if(address>=0x6000 && address<0x8000){
// Write to SaveRAM. Store in file:
// TODO: not yet
//if(this.nes.rom!=null)
// this.nes.rom.writeBatteryRam(address,value);
}
}else if(address>0x2007 && address<0x4000){
this.regWrite(0x2000 + (address & 0x7),value);
}else{
this.regWrite(address,value);
}
}
MapperDefault.prototype.load = function(address){
// Game Genie codes active?
/*if(this.gameGenieActive){
if(this.nes.gameGenie.addressMatch[address]){
tmp = nes.gameGenie.getCodeIndex(address);
// Check the code type:
if(nes.gameGenie.getCodeType(tmp) == GameGenie.TYPE_6CHAR){
// Return the code value:
return (short)nes.gameGenie.getCodeValue(tmp);
}else{
// Check whether the actual value equals the compare value:
if(nes.cpuMem[address] == nes.gameGenie.getCodeCompare(tmp)){
// The values match, so use the supplied game genie value:
return (short)nes.gameGenie.getCodeValue(tmp);
}
}
}
}*/
// Wrap around:
address &= 0xFFFF;
// Check address range:
if(address > 0x4017){
// ROM:
return this.nes.cpuMem[address];
}else if(address >= 0x2000){
// I/O Ports.
return this.regLoad(address);
}else{
// RAM (mirrored)
return this.nes.cpuMem[address&0x7FF];
}
}
MapperDefault.prototype.regLoad = function(address){
switch(address>>12){ // use fourth nibble (0xF000)
case 0:{
break;
}case 1:{
break;
}case 2:{
// Fall through to case 3
}case 3:{
// PPU Registers
switch(address&0x7){
case 0x0:{
// 0x2000:
// PPU Control Register 1.
// (the value is stored both
// in main memory and in the
// PPU as flags):
// (not in the real NES)
return this.nes.cpuMem[0x2000];
}case 0x1:{
// 0x2001:
// PPU Control Register 2.
// (the value is stored both
// in main memory and in the
// PPU as flags):
// (not in the real NES)
return this.nes.cpuMem[0x2001];
}case 0x2:{
// 0x2002:
// PPU Status Register.
// The value is stored in
// main memory in addition
// to as flags in the PPU.
// (not in the real NES)
return this.nes.ppu.readStatusRegister();
}case 0x3:{
return 0;
}case 0x4:{
// 0x2004:
// Sprite Memory read.
return this.nes.ppu.sramLoad();
}case 0x5:{
return 0;
}case 0x6:{
return 0;
}case 0x7:{
// 0x2007:
// VRAM read:
return this.nes.ppu.vramLoad();
}
}
break;
}case 4:{
// Sound+Joypad registers
switch(address-0x4015){
case 0:{
// 0x4015:
// Sound channel enable, DMC Status
//return nes.getPapu().readReg(address);
//alert("Accessed sound register")
return 0;
}case 1:{
// 0x4016:
// Joystick 1 + Strobe
return this.joy1Read();
}case 2:{
// 0x4017:
// Joystick 2 + Strobe
/*if(this.mousePressed){
// Check for white pixel nearby:
// TODO
var sx,sy,ex,ey,w;
sx = Math.max(0,this.mouseX-4);
ex = Math.min(256,this.mouseX+4);
sy = Math.max(0,this.mouseY-4);
ey = Math.min(240,this.mouseY+4);
w = 0x1<<4;
w |= 0x1<<3; // FIXME
for(var y=sy;y<ey;y++){
for(var x=sx;x<ex;x++){
if((this.nes.ppu.buffer[(y<<8)+x]&0xFFFFFF)==0xFFFFFF){
w |= 0x1<<3;
alert("Clicked on white!");
break;
}
}
}
return this.joy2Read()|w;*/
//}else{
return this.joy2Read();
//}
}
}
break;
}
}
return 0;
}
MapperDefault.prototype.regWrite = function(address, value){
switch(address){
case 0x2000:{
// PPU Control register 1
this.nes.cpuMem[address] = value;
this.nes.ppu.updateControlReg1(value);
break;
}case 0x2001:{
// PPU Control register 2
this.nes.cpuMem[address] = value;
this.nes.ppu.updateControlReg2(value);
break;
}case 0x2003:{
// Set Sprite RAM address:
this.nes.ppu.writeSRAMAddress(value);
break;
}case 0x2004:{
// Write to Sprite RAM:
this.nes.ppu.sramWrite(value);
break;
}case 0x2005:{
// Screen Scroll offsets:
this.nes.ppu.scrollWrite(value);
break;
}case 0x2006:{
// Set VRAM address:
this.nes.ppu.writeVRAMAddress(value);
break;
}case 0x2007:{
// Write to VRAM:
this.nes.ppu.vramWrite(value);
break;
}case 0x4014:{
// Sprite Memory DMA Access
this.nes.ppu.sramDMA(value);
break;
}case 0x4015:{
// Sound Channel Switch, DMC Status
//this.nes.getPapu().writeReg(address,value);
break;
}case 0x4016:{
////System.out.println("joy strobe write "+value);
// Joystick 1 + Strobe
if(value==0 && this.joypadLastWrite==1){
////System.out.println("Strobes reset.");
this.joy1StrobeState = 0;
this.joy2StrobeState = 0;
}
this.joypadLastWrite = value;
break;
}case 0x4017:{
// Sound channel frame sequencer:
//nes.papu.writeReg(address,value);
break;
}default:{
// Sound registers
////System.out.println("write to sound reg");
/*if(address >= 0x4000 && address <= 0x4017){
nes.getPapu().writeReg(address,value);
}*/
break;
}
}
}
MapperDefault.prototype.joy1Read = function(){
var ret;
switch(this.joy1StrobeState){
case 0:
case 1:
case 2:
case 3:
case 4:
case 5:
case 6:
case 7:
ret = keyboard.state1[this.joy1StrobeState];
break;
case 8:
case 9:
case 10:
case 11:
case 12:
case 13:
case 14:
case 15:
case 16:
case 17:
case 18:
ret = 0;
break;
case 19:
ret = 1;
break;
default:
ret = 0;
}
this.joy1StrobeState++;
if(this.joy1StrobeState == 24){
this.joy1StrobeState = 0;
}
return ret;
}
MapperDefault.prototype.joy2Read = function(){
var ret;
this.joy2StrobeState++;
if(this.joy2StrobeState == 24){
this.joy2StrobeState = 0;
}
switch(this.joy2StrobeState){
case 0:
case 1:
case 2:
case 3:
case 4:
case 5:
case 6:
case 7:
ret = keyboard.state2[this.joy2StrobeState];
break;
case 8:
case 9:
case 10:
case 11:
case 12:
case 13:
case 14:
case 15:
case 16:
case 17:
ret = 0;
break;
case 18:
ret = 1;
break;
default:
ret = 0;
}
return ret;
}
MapperDefault.prototype.loadROM = function(){
if(!this.nes.rom.valid || this.nes.rom.romCount<1){
alert("NoMapper: Invalid ROM! Unable to load.");
return;
}
// Load ROM into memory:
this.loadPRGROM();
// Load CHR-ROM:
this.loadCHRROM();
// Load Battery RAM (if present):
this.loadBatteryRam();
// Reset IRQ:
//nes.getCpu().doResetInterrupt();
this.nes.cpu.requestIrq(this.nes.cpu.IRQ_RESET);
}
MapperDefault.prototype.loadPRGROM = function(){
if(this.nes.rom.romCount>1){
// Load the two first banks into memory.
this.loadRomBank(0,0x8000);
this.loadRomBank(1,0xC000);
}else{
// Load the one bank into both memory locations:
this.loadRomBank(0,0x8000);
this.loadRomBank(0,0xC000);
}
}
MapperDefault.prototype.loadCHRROM = function(){
////System.out.println("Loading CHR ROM..");
if(this.nes.rom.vromCount > 0){
if(this.nes.rom.vromCount == 1){
this.loadVromBank(0,0x0000);
this.loadVromBank(0,0x1000);
}else{
this.loadVromBank(0,0x0000);
this.loadVromBank(1,0x1000);
}
}else{
//System.out.println("There aren't any CHR-ROM banks..");
}
}
MapperDefault.prototype.loadBatteryRam = function(){
if(this.nes.rom.batteryRam){
var ram = this.nes.rom.batteryRam;
if(ram!=null && ram.length==0x2000){
// Load Battery RAM into memory:
arraycopy(ram, 0, this.nes.cpuMem, 0x6000, 0x2000);
}
}
}
MapperDefault.prototype.loadRomBank = function(bank, address){
// Loads a ROM bank into the specified address.
bank %= this.nes.rom.romCount;
//var data = this.nes.rom.rom[bank];
//cpuMem.write(address,data,data.length);
arraycopy(this.nes.rom.rom[bank], 0, this.nes.cpuMem, address, 16384);
}
MapperDefault.prototype.loadVromBank = function(bank, address){
if(this.nes.rom.vromCount == 0) return;
this.nes.ppu.triggerRendering();
arraycopy(this.nes.rom.vrom[bank%this.nes.rom.vromCount],0,
this.nes.ppuMem,address,4096);
var vromTile = this.nes.rom.vromTile[bank%this.nes.rom.vromCount];
arraycopy(vromTile,0,this.nes.ppu.ptTile,address>>4,256);
}
MapperDefault.prototype.load32kRomBank = function(bank, address){
this.loadRomBank((bank*2)%this.nes.rom.romCount,address);
this.loadRomBank((bank*2+1)%this.nes.rom.romCount,address+16384);
}
MapperDefault.prototype.load8kVromBank = function(bank4kStart, address){
if(this.nes.rom.vromCount == 0) return;
this.nes.ppu.triggerRendering();
this.loadVromBank((bank4kStart)%this.nes.rom.vromCount,address);
this.loadVromBank((bank4kStart+1)%this.nes.rom.vromCount,address+4096);
}
MapperDefault.prototype.load1kVromBank = function(bank1k, address){
if(this.nes.rom.vromCount == 0)return;
this.nes.ppu.triggerRendering();
var bank4k = parseInt(bank1k/4)%this.nes.rom.vromCount;
var bankoffset = (bank1k%4)*1024;
arraycopy(this.nes.rom.vrom[bank4k],0,this.nes.ppuMem,
bankoffset,1024);
// Update tiles:
var vromTile = this.nes.rom.vromTile[bank4k];
var baseIndex = address >> 4;
for(var i=0;i<64;i++){
this.nes.ppu.ptTile[baseIndex+i] = vromTile[((bank1k%4)<<6)+i];
}
}
MapperDefault.prototype.load2kVromBank = function(bank2k, address){
if(this.nes.rom.vromCount == 0)return;
this.nes.ppu.triggerRendering();
var bank4k = parseInt(bank2k/2)%this.nes.rom.vromCount;
var bankoffset = (bank2k%2)*2048;
arraycopy(this.nes.rom.vrom[bank4k], bankoffset,
this.nes.ppuMem,address,2048);
// Update tiles:
var vromTile = this.nes.rom.vromTile[bank4k];
var baseIndex = address >> 4;
for(var i=0;i<128;i++){
this.nes.ppu.ptTile[baseIndex+i] = vromTile[((bank2k%2)<<7)+i];
}
}
MapperDefault.prototype.load8kRomBank = function(bank8k, address){
var bank16k = parseInt(bank8k/2)%this.nes.rom.romCount;
var offset = (bank8k%2)*8192;
//this.nes.cpuMem.write(address,this.nes.rom.rom[bank16k],offset,8192);
arraycopy(this.nes.rom.rom[bank16k], offset,
this.nes.cpuMem, address, 8192);
}
MapperDefault.prototype.clockIrqCounter = function(){
// Does nothing. This is used by the MMC3 mapper.
}
MapperDefault.prototype.latchAccess = function(address){
// Does nothing. This is used by MMC2.
}
MapperDefault.prototype.reset = function(){
this.joy1StrobeState = 0;
this.joy2StrobeState = 0;
this.joypadLastWrite = 0;
this.mousePressed = false;
}
function Mapper001(nes) {
this.nes = nes
// Register flags:
// Register 0:
this.mirroring = null;
this.oneScreenMirroring = null;
this.prgSwitchingArea = 1;
this.prgSwitchingSize = 1;
this.vromSwitchingSize = null;
// Register 1:
this.romSelectionReg0 = null;
// Register 2:
this.romSelectionReg1 = null;
// Register 3:
this.romBankSelect = null;
// 5-bit buffer:
this.regBuffer = null;
this.regBufferCounter = null;
}
copyPrototype(Mapper001, MapperDefault);
Mapper001.prototype.write = function(address, value){
// Writes to addresses other than MMC registers are handled by NoMapper.
if(address < 0x8000){
MapperDefault.prototype.write.apply(this, arguments);
return;
}
////System.out.println("MMC Write. Reg="+(getRegNumber(address))+" Value="+value);
// See what should be done with the written value:
if((value&128)!=0){
// Reset buffering:
this.regBufferCounter = 0;
this.regBuffer = 0;
// Reset register:
if(this.getRegNumber(address) == 0){
this.prgSwitchingArea = 1;
this.prgSwitchingSize = 1;
}
}else{
// Continue buffering:
//regBuffer = (regBuffer & (0xFF-(1<<regBufferCounter))) | ((value & (1<<regBufferCounter))<<regBufferCounter);
this.regBuffer = (this.regBuffer & (0xFF-(1<<this.regBufferCounter))) | ((value&1)<<this.regBufferCounter);
this.regBufferCounter++;
if(this.regBufferCounter == 5){
// Use the buffered value:
this.setReg(this.getRegNumber(address), this.regBuffer);
// Reset buffer:
this.regBuffer = 0;
this.regBufferCounter = 0;
}
}
}
Mapper001.prototype.setReg = function(reg, value){
var tmp,tmp2;
switch (reg) {
case 0:
// Mirroring:
tmp = value&3;
if(tmp != this.mirroring){
// Set mirroring:
this.mirroring = tmp;
if((this.mirroring & 2)==0){
// SingleScreen mirroring overrides the other setting:
this.nes.ppu.setMirroring(
this.nes.rom.SINGLESCREEN_MIRRORING);
}else{
// Not overridden by SingleScreen mirroring.
this.nes.ppu.setMirroring(
(this.mirroring&1)!=0 ?
this.nes.rom.HORIZONTAL_MIRRORING
:
this.nes.rom.VERTICAL_MIRRORING);
}
}
// PRG Switching Area;
this.prgSwitchingArea = (value>>2)&1;
// PRG Switching Size:
this.prgSwitchingSize = (value>>3)&1;
// VROM Switching Size:
this.vromSwitchingSize = (value>>4)&1;
break;
case 1:
// ROM selection:
this.romSelectionReg0 = (value>>4)&1;
// Check whether the cart has VROM:
if(this.nes.rom.vromCount > 0){
// Select VROM bank at 0x0000:
if(this.vromSwitchingSize == 0){
// Swap 8kB VROM:
////System.out.println("Swapping 8k VROM, bank="+(value&0xF)+" romSelReg="+romSelectionReg0);
if(this.romSelectionReg0==0){
this.load8kVromBank((value&0xF), 0x0000);
}else{
this.load8kVromBank(
parseInt(this.nes.rom.vromCount/2) + (value&0xF),
0x0000);
}
}else{
// Swap 4kB VROM:
////System.out.println("ROMSELREG0 = "+romSelectionReg0);
////System.out.println("Swapping 4k VROM at 0x0000, bank="+(value&0xF));
if(this.romSelectionReg0 == 0){
this.loadVromBank((value&0xF), 0x0000);
}else{
this.loadVromBank(
parseInt(this.nes.rom.vromCount/2)+(value&0xF),
0x0000);
}
}
}
break;
case 2:
// ROM selection:
this.romSelectionReg1 = (value>>4)&1;
// Check whether the cart has VROM:
if(this.nes.rom.vromCount > 0){
// Select VROM bank at 0x1000:
if(this.vromSwitchingSize == 1){
// Swap 4kB of VROM:
////System.out.println("ROMSELREG1 = "+romSelectionReg1);
////System.out.println("Swapping 4k VROM at 0x1000, bank="+(value&0xF));
if(this.romSelectionReg1 == 0){
this.loadVromBank((value&0xF),0x1000);
}else{
this.loadVromBank(
parseInt(this.nes.rom.vromCount/2)+(value&0xF),
0x1000);
}
}
}
default:
// Select ROM bank:
// -------------------------
tmp = value & 0xF;
var bank;
var baseBank = 0;
if(this.nes.rom.romCount >= 32){
// 1024 kB cart
if(this.vromSwitchingSize == 0){
if(this.romSelectionReg0 == 1){
baseBank = 16;
}
}else{
baseBank = (this.romSelectionReg0
| (this.romSelectionReg1<<1))<<3;
}
}else if(this.nes.rom.romCount >= 16){
// 512 kB cart
if(this.romSelectionReg0 == 1){
baseBank = 8;
}
}
if(this.prgSwitchingSize == 0){
// 32kB
bank = baseBank+(value&0xF);
this.load32kRomBank(bank, 0x8000);
}else{
// 16kB
bank = baseBank*2+(value&0xF);
if(this.prgSwitchingArea == 0){
this.loadRomBank(bank, 0xC000);
}else{
this.loadRomBank(bank, 0x8000);
}
}
}
}
// Returns the register number from the address written to:
Mapper001.prototype.getRegNumber = function(address){
if(address>=0x8000 && address<=0x9FFF){
return 0;
}else if(address>=0xA000 && address<=0xBFFF){
return 1;
}else if(address>=0xC000 && address<=0xDFFF){
return 2;
}else{
return 3;
}
}
Mapper001.prototype.loadROM = function(rom){
//System.out.println("Loading ROM.");
if(!this.nes.rom.valid){
alert("MMC1: Invalid ROM! Unable to load.");
return;
}
// Load PRG-ROM:
this.loadRomBank(0,0x8000); // First ROM bank..
this.loadRomBank(this.nes.rom.romCount-1,0xC000); // ..and last ROM bank.
// Load CHR-ROM:
this.loadCHRROM();
// Load Battery RAM (if present):
this.loadBatteryRam();
// Do Reset-Interrupt:
this.nes.cpu.requestIrq(this.nes.cpu.IRQ_RESET);
}
Mapper001.prototype.reset = function(){
MapperDefault.prototype.reset.apply(this);
this.regBuffer = 0;
this.regBufferCounter = 0;
// Register 0:
this.mirroring = 0;
this.oneScreenMirroring = 0;
this.prgSwitchingArea = 1;
this.prgSwitchingSize = 1;
this.vromSwitchingSize = 0;
// Register 1:
this.romSelectionReg0 = 0;
// Register 2:
this.romSelectionReg1 = 0;
// Register 3:
this.romBankSelect = 0;
}
Mapper001.prototype.switchLowHighPrgRom = function(oldSetting){
// not yet.
}
Mapper001.prototype.switch16to32 = function(){
// not yet.
}
Mapper001.prototype.switch32to16 = function(){
// not yet.
}
function Mapper002(nes) {
this.nes = nes
}
copyPrototype(Mapper002, MapperDefault);
Mapper002.prototype.write = function(address, value){
// Writes to addresses other than MMC registers are handled by NoMapper.
if(address < 0x8000){
MapperDefault.prototype.write.apply(this, arguments);
return;
}
else{
// This is a ROM bank select command.
// Swap in the given ROM bank at 0x8000:
this.loadRomBank(value,0x8000);
}
}
Mapper002.prototype.loadROM = function(rom){
if(!this.nes.rom.valid){
alert("UNROM: Invalid ROM! Unable to load.");
return;
}
// Load PRG-ROM:
this.loadRomBank(0,0x8000);
this.loadRomBank(this.nes.rom.romCount-1,0xC000);
// Load CHR-ROM:
this.loadCHRROM();
// Do Reset-Interrupt:
this.nes.cpu.requestIrq(this.nes.cpu.IRQ_RESET);
}
function Mapper004(nes) {
this.nes = nes
this.CMD_SEL_2_1K_VROM_0000 = 0;
this.CMD_SEL_2_1K_VROM_0800 = 1;
this.CMD_SEL_1K_VROM_1000 = 2;
this.CMD_SEL_1K_VROM_1400 = 3;
this.CMD_SEL_1K_VROM_1800 = 4;
this.CMD_SEL_1K_VROM_1C00 = 5;
this.CMD_SEL_ROM_PAGE1 = 6;
this.CMD_SEL_ROM_PAGE2 = 7;
this.command = null;
this.prgAddressSelect = null;
this.chrAddressSelect = null;
this.pageNumber = null;
this.irqCounter = null;
this.irqLatchValue = null;
this.irqEnable = null;
this.prgAddressChanged = false;
}
copyPrototype(Mapper004, MapperDefault);
Mapper004.prototype.write = function(address, value){
// Writes to addresses other than MMC registers are handled by NoMapper.
if(address < 0x8000){
MapperDefault.prototype.write.apply(this, arguments);
return;
}
switch (address) {
case 0x8000:
// Command/Address Select register
this.command = value&7;
var tmp = (value>>6)&1;
if(tmp != this.prgAddressSelect){
this.prgAddressChanged = true;
}
this.prgAddressSelect = tmp;
this.chrAddressSelect = (value>>7)&1;
break;
case 0x8001:
// Page number for command
this.executeCommand(this.command,value);
break;
case 0xA000:
// Mirroring select
if((value&1) != 0){
this.nes.ppu.setMirroring(this.nes.rom.HORIZONTAL_MIRRORING);
}else{
this.nes.ppu.setMirroring(this.nes.rom.VERTICAL_MIRRORING);
}
break;
case 0xA001:
// SaveRAM Toggle
// TODO
//nes.getRom().setSaveState((value&1)!=0);
break;
case 0xC000:
// IRQ Counter register
this.irqCounter = value;
//nes.ppu.mapperIrqCounter = 0;
break;
case 0xC001:
// IRQ Latch register
this.irqLatchValue = value;
break;
case 0xE000: