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mappers.js
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mappers.js
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var singleScreen = false;
var fourScreen = false;
var prgBanks, chrBanks;
var prgRam = new Uint8Array(0x2000);
// TODO: GTROM (111), VRC6 (24/26), MMC5 (5)
// Default helper functions for most mapper types
function initPrgBanks(size) {
prgBanks = new Uint8Array(0x8000 / size);
var shiftAmount = Math.log(size)/Math.log(2);
var bankMask = size-1;
mapRead[1] = function(address) {
if (!(address & 0x8000)) return prgRam[address - 0x6000];
var romAddress = address & 0x7FFF;
return prgData[(prgBanks[romAddress >> shiftAmount] << shiftAmount) | (romAddress & bankMask)];
};
mapWrite[1] = function (address, value) {
if (!(address & 0x8000)) prgRam[address - 0x6000] = value;
// No writing to cartridge space by default
};
}
// Warning: Using this method cause a fairly large performance overhead
function initChrBanks(size, isRam, banks) {
chrBanks = new Uint8Array(0x2000 / size);
if (isRam) chrData = new Uint8Array(size * banks);
var shiftAmount = Math.log(size)/Math.log(2);
var bankMask = size-1;
mapChrRead = function(address) {
return chrData[(chrBanks[address >> shiftAmount] << shiftAmount) | (address & bankMask)];
};
mapChrWrite = function() {};
if (isRam) mapChrWrite = function (address, value) {
chrData[(chrBanks[address >> shiftAmount] << shiftAmount) | (address & bankMask)] = value;
};
getChrColor = function(tileOffset, tileX, isBg) {
switch (tileX) {
case 0:
return ((mapChrRead(tileOffset, isBg) >> 7) & 0x01) | ((mapChrRead(tileOffset+8, isBg) >> 6) & 0x02);
case 1:
return ((mapChrRead(tileOffset, isBg) >> 6) & 0x01) | ((mapChrRead(tileOffset+8, isBg) >> 5) & 0x02);
case 2:
return ((mapChrRead(tileOffset, isBg) >> 5) & 0x01) | ((mapChrRead(tileOffset+8, isBg) >> 4) & 0x02);
case 3:
return ((mapChrRead(tileOffset, isBg) >> 4) & 0x01) | ((mapChrRead(tileOffset+8, isBg) >> 3) & 0x02);
case 4:
return ((mapChrRead(tileOffset, isBg) >> 3) & 0x01) | ((mapChrRead(tileOffset+8, isBg) >> 2) & 0x02);
case 5:
return ((mapChrRead(tileOffset, isBg) >> 2) & 0x01) | ((mapChrRead(tileOffset+8, isBg) >> 1) & 0x02);
case 6:
return ((mapChrRead(tileOffset, isBg) >> 1) & 0x01) | ((mapChrRead(tileOffset+8, isBg)) & 0x02);
case 7:
return ((mapChrRead(tileOffset, isBg)) & 0x01) | ((mapChrRead(tileOffset+8, isBg) << 1) & 0x02);
}
}
}
// UxROM
mappers[2] = function() {
initPrgBanks(0x4000);
prgBanks[1] = (prgData.byteLength / 0x4000) - 1; // Fix last bank
var unrom = new HwRegister(null, function(value) {
prgBanks[0] = value & 0x0F;
});
for (var i = 0x8000; i < 0x10000; i++) {
hwRegisters[i] = unrom;
}
};
// UNROM 512
mappers[30] = function() {
var prgBank = 0, chrBank = 0;
if (fourScreen && vMirroring) {
var nts = [
new Uint8Array(0x400),
new Uint8Array(0x400),
new Uint8Array(0x400),
new Uint8Array(0x400)
];
nametables = [nts[0],nts[1],nts[2],nts[3]];
attributetables = [nts[0].subarray(-0x40),nts[1].subarray(-0x40),nts[2].subarray(-0x40),nts[3].subarray(-0x40)];
}
if (fourScreen && !vMirroring) {
singleScreen = true;
}
var chrRamBackup = [new Uint8Array(0x2000), new Uint8Array(0x2000), new Uint8Array(0x2000), new Uint8Array(0x2000)];
var unrom = new HwRegister(null, function(value) {
chrRamBackup[chrBank].set(ppuMemory.subarray(0, 0x2000));
prgBank = value & 0x1F;
chrBank = (value & 0x60) >> 5;
var ntIndex = (value & 0x80) >> 7;
if (!fourScreen) {
singleScreen = ntIndex != true;
setMirroring();
if (singleScreen) ntIndex = 0;
}
else {
// TODO: PPU $3000-$3EFF RAM
}
if (singleScreen) {
nametables = [nameTableSources[ntIndex],nameTableSources[ntIndex],nameTableSources[ntIndex],nameTableSources[ntIndex]];
attributetables = [attrSources[ntIndex],attrSources[ntIndex],attrSources[ntIndex],attrSources[ntIndex]];
}
cpuMemory.set(prgData.subarray(prgBank*0x4000, (prgBank+1)*0x4000), 0x8000);
ppuMemory.set(chrRamBackup[chrBank], 0);
});
for (var i = 0x8000; i < 0x10000; i++) {
hwRegisters[i] = unrom;
}
};
// MMC1
mappers[1] = function() {
//initPrgBanks(0x4000);
//initChrBanks(0x1000);
//prgBanks[1] = (prgData.byteLength / 0x4000) - 1;
var count = 0;
var data = 0;
var separateChr = false;
var prgMode = 3;
var prgIndex = 0;
var chrIndex0 = 0;
var chrIndex1 = 0;
function reset() {
count = 0;
data = 0;
}
function mapperWrite(value) {
if ((value & 0x80) != 0) {
reset();
return;
}
data >>= 1;
data |= (value & 0x01) << 4;
count++;
}
function setPrg() {
if (prgMode <= 1) {
var bigIndex = prgIndex & 0b1110;
cpuMemory.set(prgData.subarray(bigIndex*0x8000, (bigIndex+1)*0x8000), 0x8000);
}
else if (prgMode == 2) {
cpuMemory.set(prgData.subarray(prgIndex*0x4000, (prgIndex+1)*0x4000), 0xC000);
cpuMemory.set(prgData.subarray(0, 0x4000), 0x8000);
}
else if (prgMode == 3) {
cpuMemory.set(prgData.subarray(prgIndex*0x4000, (prgIndex+1)*0x4000), 0x8000);
cpuMemory.set(prgData.subarray(-0x4000), 0xC000);
}
}
function setChr() {
if (separateChr) {
ppuMemory.set(chrData.subarray(chrIndex0*0x1000, (chrIndex0+1)*0x1000), 0);
ppuMemory.set(chrData.subarray(chrIndex1*0x1000, (chrIndex1+1)*0x1000), 0x1000);
}
else {
var chrIndex = (chrIndex0 & 0b11110);
ppuMemory.set(chrData.subarray(chrIndex0*0x1000, (chrIndex0+2)*0x1000), 0);
}
}
var ctrl = new HwRegister(null, function(value) {
mapperWrite(value);
if (count != 5) return;
var mirroring = data & 0x03;
vMirroring = (mirroring == 2);
setMirroring();
singleScreen = false;
if (mirroring == 0) {
singleScreen = true;
nametables = [nameTableSources[1],nameTableSources[1],nameTableSources[1],nameTableSources[1]];
attributetables = [attrSources[1],attrSources[1],attrSources[1],attrSources[1]];
}
if (mirroring == 1) {
singleScreen = true;
nametables = [nameTableSources[0],nameTableSources[0],nameTableSources[0],nameTableSources[0]];
attributetables = [attrSources[0],attrSources[0],attrSources[0],attrSources[0]];
}
separateChr = ((data & 0x10) != 0);
prgMode = (data & 0b01100) >> 2;
setPrg();
setChr();
reset();
});
var chrb0 = new HwRegister(null, function(value) {
mapperWrite(value);
if (count != 5) return;
chrIndex0 = data;
setChr();
reset();
});
var chrb1 = new HwRegister(null, function(value) {
mapperWrite(value);
if (count != 5) return;
chrIndex1 = data;
setChr();
reset();
});
var prgb = new HwRegister(null, function(value) {
mapperWrite(value);
if (count != 5) return;
prgIndex = data & 0b01111;
setPrg();
reset();
});
for (var i = 0x8000; i < 0xA000; i++) {
hwRegisters[i] = ctrl;
}
for (var i = 0xA000; i < 0xC000; i++) {
hwRegisters[i] = chrb0;
}
for (var i = 0xC000; i < 0xE000; i++) {
hwRegisters[i] = chrb1;
}
for (var i = 0xE000; i < 0x10000; i++) {
hwRegisters[i] = prgb;
}
};
// MMC2
var mapperListener = null;
mappers[9] = function() {
cpuMemory.set(prgData.subarray(-0x6000), 0xA000);
var L0 = false, L1 = false;
var chr00 = 0, chr01 = 0, chr10 = 0, chr11 = 0;
mapperListener = [];
mapperListener[0x0FD8] = function() { L0 = false; setChr(); };
mapperListener[0x0FE8] = function() { L0 = true; setChr(); };
for (var i = 0; i < 8; i++) {
mapperListener[0x1FD8 + i] = function() { L1 = false; setChr(); };
mapperListener[0x1FE8 + i] = function() { L1 = true; setChr(); };
}
function setChr() {
var chr0 = L0 ? chr01 : chr00;
var chr1 = L1 ? chr11 : chr10;
ppuMemory.set(chrData.subarray(chr0*0x1000, (chr0+1)*0x1000), 0);
ppuMemory.set(chrData.subarray(chr1*0x1000, (chr1+1)*0x1000), 0x1000);
}
var prgSelect = new HwRegister(null, function(value) {
var prgIndex = value & 0x0F;
cpuMemory.set(prgData.subarray(prgIndex*0x2000, (prgIndex+1)*0x2000), 0x8000);
});
var mirroring = new HwRegister(null, function(value) {
vMirroring = (value & 1) == 0;
setMirroring();
});
var chr00Select = new HwRegister(null, function(value) { chr00 = value & 0x1F; setChr(); });
var chr01Select = new HwRegister(null, function(value) { chr01 = value & 0x1F; setChr(); });
var chr10Select = new HwRegister(null, function(value) { chr10 = value & 0x1F; setChr(); });
var chr11Select = new HwRegister(null, function(value) { chr11 = value & 0x1F; setChr(); });
for (var i = 0xA000; i < 0xB000; i++) hwRegisters[i] = prgSelect;
for (var i = 0xB000; i < 0xC000; i++) hwRegisters[i] = chr00Select;
for (var i = 0xC000; i < 0xD000; i++) hwRegisters[i] = chr01Select;
for (var i = 0xD000; i < 0xE000; i++) hwRegisters[i] = chr10Select;
for (var i = 0xE000; i < 0xF000; i++) hwRegisters[i] = chr11Select;
for (var i = 0xF000; i < 0x10000; i++) hwRegisters[i] = mirroring;
}
// MMC3 and MMC6
mappers[68] = mappers[4] = function() {
var selectedBank = 0;
var invertChr = false;
var invertPrg = false;
var enablePrgRam = true;
var bankAssignments = new Uint8Array(8);
function setBanks() {
var secondToLastBank = prgData.subarray(prgData.byteLength - 0x4000, prgData.byteLength - 0x2000);
if (invertPrg) {
cpuMemory.set(prgData.subarray(bankAssignments[6]*0x2000, (bankAssignments[6]+1)*0x2000), 0xC000);
cpuMemory.set(secondToLastBank, 0x8000);
}
else {
cpuMemory.set(prgData.subarray(bankAssignments[6]*0x2000, (bankAssignments[6]+1)*0x2000), 0x8000);
cpuMemory.set(secondToLastBank, 0xC000);
}
cpuMemory.set(prgData.subarray(bankAssignments[7]*0x2000, (bankAssignments[7]+1)*0x2000), 0xA000);
if (invertChr) {
ppuMemory.set(chrData.subarray(bankAssignments[0]*0x400, (bankAssignments[0]+2)*0x400), 0x1000);
ppuMemory.set(chrData.subarray(bankAssignments[1]*0x400, (bankAssignments[1]+2)*0x400), 0x1800);
ppuMemory.set(chrData.subarray(bankAssignments[2]*0x400, (bankAssignments[2]+1)*0x400), 0x0000);
ppuMemory.set(chrData.subarray(bankAssignments[3]*0x400, (bankAssignments[3]+1)*0x400), 0x0400);
ppuMemory.set(chrData.subarray(bankAssignments[4]*0x400, (bankAssignments[4]+1)*0x400), 0x0800);
ppuMemory.set(chrData.subarray(bankAssignments[5]*0x400, (bankAssignments[5]+1)*0x400), 0x0C00);
}
else {
ppuMemory.set(chrData.subarray(bankAssignments[0]*0x400, (bankAssignments[0]+2)*0x400), 0x0000);
ppuMemory.set(chrData.subarray(bankAssignments[1]*0x400, (bankAssignments[1]+2)*0x400), 0x0800);
ppuMemory.set(chrData.subarray(bankAssignments[2]*0x400, (bankAssignments[2]+1)*0x400), 0x1000);
ppuMemory.set(chrData.subarray(bankAssignments[3]*0x400, (bankAssignments[3]+1)*0x400), 0x1400);
ppuMemory.set(chrData.subarray(bankAssignments[4]*0x400, (bankAssignments[4]+1)*0x400), 0x1800);
ppuMemory.set(chrData.subarray(bankAssignments[5]*0x400, (bankAssignments[5]+1)*0x400), 0x1C00);
}
}
var mirroring = new HwRegister(null, function(value) {
value &= 1;
vMirroring = (value == 0);
setMirroring();
});
var bankSelect = new HwRegister(null, function(value) {
selectedBank = value & 0b0111;
invertChr = (value & 0x80) != 0;
invertPrg = (value & 0x40) != 0;
enablePrgRam = (value & 0x20) != 0;
setBanks();
});
var bankData = new HwRegister(null, function(value) {
if (selectedBank >= 6) {
value &= (prgData.byteLength / 0x2000 - 1);
}
else {
value &= (chrData.byteLength / 0x400 - 1);
}
bankAssignments[selectedBank] = value;
setBanks();
});
var ramProtect = new HwRegister(null, function(value) {
if (!enablePrgRam) return;
// TODO: RAM write protect
});
var irqLatch = new HwRegister(null, function(value) {
irqCounter[1] = value;
});
var irqReload = new HwRegister(null, function() {
irqCounter[0] = 0;
});
var irqDisable = new HwRegister(null, function() {
scanlineIrqEnabled = false;
pendingIrq = false;
});
var irqEnable = new HwRegister(null, function() {
scanlineIrqEnabled = true;
});
for (var i = 0x8000; i < 0xA000; i += 2) {
hwRegisters[i] = bankSelect;
}
for (var i = 0x8001; i < 0xA000; i += 2) {
hwRegisters[i] = bankData;
}
for (var i = 0xA000; i < 0xC000; i += 2) {
hwRegisters[i] = mirroring;
}
for (var i = 0xA001; i < 0xC000; i += 2) {
hwRegisters[i] = ramProtect;
}
for (var i = 0xC000; i < 0xE000; i += 2) {
hwRegisters[i] = irqLatch;
}
for (var i = 0xC001; i < 0xE000; i += 2) {
hwRegisters[i] = irqReload;
}
for (var i = 0xE000; i < 0x10000; i += 2) {
hwRegisters[i] = irqDisable;
}
for (var i = 0xE001; i < 0x10000; i += 2) {
hwRegisters[i] = irqEnable;
}
};
var scanlineIrqEnabled = false;
var irqCounter = new Uint8Array(3); // 0 = actual counter, 1 = MMC3 latch, 2 = MMC5 latch
// AxROM
mappers[7] = function() {
singleScreen = true;
var bankSelect = new HwRegister(null, function(value) {
var nts = (value & 0x10) >> 4;
nametables = [nameTableSources[nts],nameTableSources[nts],nameTableSources[nts],nameTableSources[nts]];
attributetables = [attrSources[nts],attrSources[nts],attrSources[nts],attrSources[nts]];
var bankIndex = value & 7;
cpuMemory.set(prgData.subarray(bankIndex*0x8000, (bankIndex+1)*0x8000), 0x8000);
});
for (var i = 0x8000; i < 0x10000; i++) {
hwRegisters[i] = bankSelect;
}
};
// CNROM
mappers[3] = function() {
var bankSelect = new HwRegister(null, function(value) {
var bankIndex = value & 3;
ppuMemory.set(chrData.subarray(bankIndex*0x2000, (bankIndex+1)*0x2000), 0);
});
for (var i = 0x8000; i < 0x10000; i++) {
hwRegisters[i] = bankSelect;
}
};
// SunSoft 5/FME-7
mappers[69] = function() {
var commands = [];
var currentCommand = 0;
var hasPrgRam = false;
function chrBank(bankIndex, bank) {
bankIndex &= (chrData.byteLength / 0x400 - 1)
ppuMemory.set(chrData.subarray(bankIndex*0x400, (bankIndex+1)*0x400), bank * 0x400);
};
var prgRamBackup = new Uint8Array(0x2000);
function prgBank(value, bank) {
var test = frame;
var bankIndex = value & 0x3F & (prgData.byteLength / 0x2000 - 1);
bank &= 3;
var prgBank = prgData.subarray(bankIndex*0x2000, (bankIndex+1)*0x2000);
if (bank == 0) {
if (hasPrgRam) prgRamBackup.set(cpuMemory.subarray(0x6000, 0x8000));
hasPrgRam = (value & 0x40) != 0;
cpuMemory.set(hasPrgRam ? prgRamBackup : prgBank, 0x6000);
}
else {
cpuMemory.set(prgBank, 0x6000 + (bank * 0x2000));
}
};
function mirroring(value) {
value &= 3;
vMirroring = value == 0;
setMirroring();
singleScreen = false;
if ((value & 2) != 0) {
singleScreen = true;
var nts = (value & 1);
nametables = [nameTableSources[nts],nameTableSources[nts],nameTableSources[nts],nameTableSources[nts]];
attributetables = [attrSources[nts],attrSources[nts],attrSources[nts],attrSources[nts]];
}
}
function irqControl(value) {
cycleIrqEnabled = (value & 0x01) != 0;
cycleCountEnabled = (value & 0x80) != 0;
pendingIrq = false;
}
function irqLow(value) { cycleCounterBytes[0] = value; }
function irqHigh(value) { cycleCounterBytes[1] = value; }
commands[0] = commands[1] = commands[2] = commands[3] = commands[4] = commands[5] = commands[6] = commands[7] = chrBank;
commands[8] = commands[9] = commands[10] = commands[11] = prgBank;
commands[12] = mirroring;
commands[13] = irqControl;
commands[14] = irqLow;
commands[15] = irqHigh;
var cmd = new HwRegister(null, function(value) {
currentCommand = value & 0x0F;
});
var param = new HwRegister(null, function(value) {
if (commands[currentCommand]) commands[currentCommand](value, currentCommand);
});
for (var i = 0x8000; i < 0xA000; i++) {
hwRegisters[i] = cmd;
}
for (var i = 0xA000; i < 0xC000; i++) {
hwRegisters[i] = param;
}
};
var cycleIrqEnabled = false;
var cycleCountEnabled = false;
var cycleCounterBuffer = new ArrayBuffer(2);
var cycleCounterBytes = new Uint8Array(cycleCounterBuffer);
var cycleCounter = new Uint16Array(cycleCounterBuffer);
// GTROM
mappers[111] = function() {
var extraNametables = [
new Uint8Array(0x400),
new Uint8Array(0x400),
new Uint8Array(0x400),
new Uint8Array(0x400)
];
var chrRamBackup = [new Uint8Array(0x2000), new Uint8Array(0x2000)];
var chrRamIndex = 0;
var bankSelect = new HwRegister(null, function(value) {
var prgIndex = value & 0x0F & (prgData.byteLength / 0x8000 - 1);
cpuMemory.set(prgData.subarray(prgIndex*0x8000, (prgIndex+1)*0x8000), 0x8000);
chrRamBackup[chrRamIndex].set(ppuMemory.subarray(0, 0x2000));
chrRamIndex = (value >> 4) & 1;
ppuMemory.set(chrRamBackup[chrRamIndex], 0);
var nts = ((value >> 5) & 1) == 0 ? nameTableSources : extraNametables;
nametables = [nts[0],nts[1],nts[2],nts[3]];
attributetables = [nts[0].subarray(-0x40),nts[1].subarray(-0x40),nts[2].subarray(-0x40),nts[3].subarray(-0x40)];
});
for (var i = 0x5000; i < 0x6000; i++) {
hwRegisters[i] = bankSelect;
}
for (var i = 0x7000; i < 0x8000; i++) {
hwRegisters[i] = bankSelect;
}
bankSelect.store(0);
};
var mmc5ScanlineIrqEnabled = false;
mappers[5] = function() {
var prgMask = (prgData.byteLength / 0x2000) - 1;
var prgRamMask = (0x40000 / 0x2000) - 1;
var chrMask = (chrData.byteLength / 0x400) - 1;
var mmc5Ram = new Uint8Array(0x40000);
var fillNametable = new Uint8Array(0x400);
var fillNametableAttributes = new Uint8Array(fillNametable.buffer, 0x3C0, 0x40);
bgChrMemory = new Uint8Array(0x2000); // ghetto banking for performance reasons
var prgMode = 0, chrMode = 0;
var prgIndex = new Uint8Array(5);
var chrIndex = new Uint8Array(8);
var bgChrIndex = new Uint8Array(8);
var prgIndexRam = new Uint8Array(5);
initChrBanks(0x400);
initPrgBanks(0x2000);
var bgChrBanks = new Uint8Array(8);
mapChrRead = function(address, isBg) {
var bank = isBg && tallSprites ? bgChrBanks[address >> 10] : chrBanks[address >> 10];
return chrData[(bank << 10) | (address & 0x3ff)];
};
/*
PRG RAM mode: (needs to be extended to take extended RAM into consideration, or CV3 will break)
prgBanks = new Uint8Array(4);
prgRam = new Uint8Array(mmc5Ram.buffer, 0, 0x2000);
var shiftAmount = 13;
var bankMask = 0x1FFF;
mapRead[1] = function(address) {
if (!(address & 0x8000)) return prgRam[address - 0x6000];
var romAddress = address & 0x7FFF;
var slot = romAddress >> shiftAmount;
if (prgIndexRam[slot]) return mmc5Ram[((prgBanks[slot] & prgRamMask) << shiftAmount) | (romAddress & bankMask)];
return prgData[(prgBanks[slot] << shiftAmount) | (romAddress & bankMask)];
};
mapWrite[1] = function (address, value) {
if (!(address & 0x8000)) prgRam[address - 0x6000] = value;
var romAddress = address & 0x7FFF;
var slot = romAddress >> shiftAmount;
if (prgIndexRam[slot]) mmc5Ram[((prgBanks[slot] & prgRamMask) << shiftAmount) | (romAddress & bankMask)] = value;
};*/
setNametables(vMirroring ? 0x44 : 0x50);
setPrgIndex(4, 0xFF);
function setPrgMode(value) {
prgMode = value & 3;
setPrg();
}
function setChrMode(value) {
chrMode = value & 3;
setChr();
}
function setPrgIndex(slot, index) {
if (slot > 0 && slot < 4) prgIndexRam[slot] = (index & 0x80) != 0
prgIndex[slot] = index & 0x7F & prgMask;
setPrg();
}
function setChrIndex(slot, index) {
chrIndex[slot] = index & chrMask;
setChr();
}
function setBgChrIndex(slot, index) {
bgChrIndex[slot] = index & chrMask;
setChr();
}
function setPrg() {
prgRam = new Uint8Array(mmc5Ram.buffer, 0x2000 * prgIndex[0], 0x2000);
// TODO: RAM slots (override PRG read)
switch (prgMode) {
case 0:
prgBanks[0] = (prgIndex[4] & 0xFC);
prgBanks[1] = (prgIndex[4] & 0xFC) | 1;
prgBanks[2] = (prgIndex[4] & 0xFC) | 2;
prgBanks[3] = (prgIndex[4] & 0xFC) | 3;
break;
case 1:
prgBanks[0] = (prgIndex[2] & 0xFE);
prgBanks[1] = (prgIndex[2] & 0xFE) | 1;
prgBanks[2] = (prgIndex[4] & 0xFE);
prgBanks[3] = (prgIndex[4] & 0xFE) | 1;
break;
case 2:
prgBanks[0] = (prgIndex[2] & 0xFE);
prgBanks[1] = (prgIndex[2] & 0xFE) | 1;
prgBanks[2] = prgIndex[3];
prgBanks[3] = prgIndex[4];
break;
case 3:
prgBanks[0] = prgIndex[1];
prgBanks[1] = prgIndex[2];
prgBanks[2] = prgIndex[3];
prgBanks[3] = prgIndex[4];
break;
}
}
function setChr() {
switch (chrMode) {
case 0:
chrBanks[0] = (chrIndex[7] << 3);
chrBanks[1] = (chrIndex[7] << 3) | 1;
chrBanks[2] = (chrIndex[7] << 3) | 2;
chrBanks[3] = (chrIndex[7] << 3) | 3;
chrBanks[4] = (chrIndex[7] << 3) | 4;
chrBanks[5] = (chrIndex[7] << 3) | 5;
chrBanks[6] = (chrIndex[7] << 3) | 6;
chrBanks[7] = (chrIndex[7] << 3) | 7;
bgChrBanks[0] = (bgChrIndex[3] << 3);
bgChrBanks[1] = (bgChrIndex[3] << 3) | 1;
bgChrBanks[2] = (bgChrIndex[3] << 3) | 2;
bgChrBanks[3] = (bgChrIndex[3] << 3) | 3;
bgChrBanks[4] = (bgChrIndex[3] << 3) | 4;
bgChrBanks[5] = (bgChrIndex[3] << 3) | 5;
bgChrBanks[6] = (bgChrIndex[3] << 3) | 6;
bgChrBanks[7] = (bgChrIndex[3] << 3) | 7;
break;
case 1:
chrBanks[0] = (chrIndex[3] << 2);
chrBanks[1] = (chrIndex[3] << 2) | 1;
chrBanks[2] = (chrIndex[3] << 2) | 2;
chrBanks[3] = (chrIndex[3] << 2) | 3;
chrBanks[4] = (chrIndex[7] << 2);
chrBanks[5] = (chrIndex[7] << 2) | 1;
chrBanks[6] = (chrIndex[7] << 2) | 2;
chrBanks[7] = (chrIndex[7] << 2) | 3;
bgChrBanks[0] = (bgChrIndex[3] << 2);
bgChrBanks[1] = (bgChrIndex[3] << 2) | 1;
bgChrBanks[2] = (bgChrIndex[3] << 2) | 2;
bgChrBanks[3] = (bgChrIndex[3] << 2) | 3;
bgChrBanks[4] = (bgChrIndex[3] << 2);
bgChrBanks[5] = (bgChrIndex[3] << 2) | 1;
bgChrBanks[6] = (bgChrIndex[3] << 2) | 2;
bgChrBanks[7] = (bgChrIndex[3] << 2) | 3;
break;
case 2:
chrBanks[0] = (chrIndex[1] << 1);
chrBanks[1] = (chrIndex[1] << 1) | 1;
chrBanks[2] = (chrIndex[3] << 1);
chrBanks[3] = (chrIndex[3] << 1) | 1;
chrBanks[4] = (chrIndex[5] << 1);
chrBanks[5] = (chrIndex[5] << 1) | 1;
chrBanks[6] = (chrIndex[7] << 1);
chrBanks[7] = (chrIndex[7] << 1) | 1;
bgChrBanks[0] = (bgChrIndex[1] << 1);
bgChrBanks[1] = (bgChrIndex[1] << 1) | 1;
bgChrBanks[2] = (bgChrIndex[3] << 1);
bgChrBanks[3] = (bgChrIndex[3] << 1) | 1;
bgChrBanks[4] = (bgChrIndex[1] << 1);
bgChrBanks[5] = (bgChrIndex[1] << 1) | 1;
bgChrBanks[6] = (bgChrIndex[3] << 1);
bgChrBanks[7] = (bgChrIndex[3] << 1) | 1;
break;
case 3:
chrBanks[0] = chrIndex[0];
chrBanks[1] = chrIndex[1];
chrBanks[2] = chrIndex[2];
chrBanks[3] = chrIndex[3];
chrBanks[4] = chrIndex[4];
chrBanks[5] = chrIndex[5];
chrBanks[6] = chrIndex[6];
chrBanks[7] = chrIndex[7];
bgChrBanks[0] = bgChrIndex[0];
bgChrBanks[1] = bgChrIndex[1];
bgChrBanks[2] = bgChrIndex[2];
bgChrBanks[3] = bgChrIndex[3];
bgChrBanks[4] = bgChrIndex[0];
bgChrBanks[5] = bgChrIndex[1];
bgChrBanks[6] = bgChrIndex[2];
bgChrBanks[7] = bgChrIndex[3];
break;
}
bgChrMemory.set(chrData.subarray(bgChrBanks[0]*0x400, (bgChrBanks[0]+1)*0x400), 0x0000);
bgChrMemory.set(chrData.subarray(bgChrBanks[1]*0x400, (bgChrBanks[1]+1)*0x400), 0x0400);
bgChrMemory.set(chrData.subarray(bgChrBanks[2]*0x400, (bgChrBanks[2]+1)*0x400), 0x0800);
bgChrMemory.set(chrData.subarray(bgChrBanks[3]*0x400, (bgChrBanks[3]+1)*0x400), 0x0C00);
bgChrMemory.set(chrData.subarray(bgChrBanks[4]*0x400, (bgChrBanks[4]+1)*0x400), 0x1000);
bgChrMemory.set(chrData.subarray(bgChrBanks[5]*0x400, (bgChrBanks[5]+1)*0x400), 0x1400);
bgChrMemory.set(chrData.subarray(bgChrBanks[6]*0x400, (bgChrBanks[6]+1)*0x400), 0x1800);
bgChrMemory.set(chrData.subarray(bgChrBanks[7]*0x400, (bgChrBanks[7]+1)*0x400), 0x1C00);
}
function setNametable(nti, mapping) {
switch (mapping) {
case 0:
case 1:
nametables[nti] = nameTableSources[mapping];
attributetables[nti] = attrSources[mapping];
break;
case 2:
// TODO: extended RAM
nametables[nti] = nameTableSources[0];
attributetables[nti] = attrSources[0];
break;
case 3:
nametables[nti] = fillNametable;
attributetables[nti] = fillNametableAttributes;
break;
}
}
function setNametables(value) {
setNametable(0, value & 3);
value >>= 2;
setNametable(1, value & 3);
value >>= 2;
setNametable(2, value & 3);
value >>= 2;
setNametable(3, value & 3);
}
function irqLatch(value) {
irqCounter[2] = value;
}
var irqStatus = new HwRegister(function() {
var returnValue = (pendingIrq == 2 ? 0x0 : 0) | (((showBG || showSprites) && scanline < 240 && pixelOnScanline < 259) ? 0x40 : 0);
pendingIrq = false;
return returnValue;
}, function (value) {
mmc5ScanlineIrqEnabled = (value & 0x80) != 0;
});
hwRegisters[0x5100] = new HwRegister(null, setPrgMode);
hwRegisters[0x5101] = new HwRegister(null, setChrMode);
// TODO: prg ram protect
// TODO: extended ram
hwRegisters[0x5105] = new HwRegister(null, setNametables);
hwRegisters[0x5106] = new HwRegister(null, function(value) { fillNametable.fill(value, 0, 0x3C0); });
hwRegisters[0x5107] = new HwRegister(null, function(value) { fillNametable.fill(value, 0x3C0); });
hwRegisters[0x5113] = new HwRegister(null, function(value) { setPrgIndex(0, value); });
hwRegisters[0x5114] = new HwRegister(null, function(value) { setPrgIndex(1, value); });
hwRegisters[0x5115] = new HwRegister(null, function(value) { setPrgIndex(2, value); });
hwRegisters[0x5116] = new HwRegister(null, function(value) { setPrgIndex(3, value); });
hwRegisters[0x5117] = new HwRegister(null, function(value) { setPrgIndex(4, value); });
hwRegisters[0x5120] = new HwRegister(null, function(value) { setChrIndex(0, value); });
hwRegisters[0x5121] = new HwRegister(null, function(value) { setChrIndex(1, value); });
hwRegisters[0x5122] = new HwRegister(null, function(value) { setChrIndex(2, value); });
hwRegisters[0x5123] = new HwRegister(null, function(value) { setChrIndex(3, value); });
hwRegisters[0x5124] = new HwRegister(null, function(value) { setChrIndex(4, value); });
hwRegisters[0x5125] = new HwRegister(null, function(value) { setChrIndex(5, value); });
hwRegisters[0x5126] = new HwRegister(null, function(value) { setChrIndex(6, value); });
hwRegisters[0x5127] = new HwRegister(null, function(value) { setChrIndex(7, value); });
hwRegisters[0x5128] = new HwRegister(null, function(value) { setBgChrIndex(0, value); });
hwRegisters[0x5129] = new HwRegister(null, function(value) { setBgChrIndex(1, value); });
hwRegisters[0x512A] = new HwRegister(null, function(value) { setBgChrIndex(2, value); });
hwRegisters[0x512B] = new HwRegister(null, function(value) { setBgChrIndex(3, value); });
hwRegisters[0x5203] = new HwRegister(null, irqLatch);
hwRegisters[0x5204] = irqStatus;
}