Adding JavaScript files for 65C02 emulator with monitor and disassembler, and the start of a memory and I/o module for the Apple //c

This commit is contained in:
Jason Meiring 2015-01-05 21:07:43 -08:00
parent 19bb34c1f3
commit 01195c203a
8 changed files with 1898 additions and 0 deletions

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apple_iic_memory.js Normal file
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function AppleIIcMemory() {
this.bank0 = new Array(65536);
this.bank1 = new Array(65536);
this.rom = new Array(12288);
this.lastRead = 0x0000; // used to detect write protection disable
// (requires two subsequent reads at the same address)
this.hardReset(); // set the default states
}
AppleIIcMemory.prototype.hardReset = function() {
// Soft switches - start in default state
this.altzp = this.bank0; // altzp = 0; use main bank
this.enlcram = false; // read rom
this.offset = 0x1000; // offset (for upper bank switched ROM/RAM)
// offset for bank 1 = 0x0000, offset for bank2 = 0x1000
this.nowrite = false; // write upper 16Kram
this.ramrd = this.bank0; // read from main 48K bank
this.ramwrt = this.bank0; // write to main 48K bank
this.store80 = false; // RAMRD/RAMWRT controls lower 48K
this.page2 = this.bank0; // text/graphics on main bank (if store80 enabled)
this.hires = false; // text display mode
this.altchar = false; // display primary character set
this.col80 = false; // 40 character text
this.textmode = true; // display text
this.mixed = false; // display only text
this.ioudis = true; // disable access to IOU (mouse hardware)
this.dhires = false; // double high resolution off
};
AppleIIcMemory.prototype.setData = function(addr, data) {
if (addr < 0x0200) {
// Switched zero page and stack: controlled by ALTZP
this.altzp[addr] = data;
} else if (addr < 0xC000) {
// 48K bank switched RAM: controlled by 80STORE & RAMWRT
var ram = this.ramwrt;
if (this.store80) {
// 80STORE is enabled: this affects the text page separately
if (addr >= 0x0300 && addr < 0x0700) {
ram = this.page2;
} else if (this.hires && addr >= 0x2000 && add < 0x3F00) {
ram = this.page2;
}
}
ram[addr] = data;
} else if (addr < 0xC100) {
// Hardware page
switch(addr) {
case 0xC000: // action:W - 80STORE Off: RAMRD and RAMWRT determine RAM locations
this.store80 = false;
break;
case 0xC001: // action:W - 80STORE On: PAGE2 switches between TLP1 and TLP1X
this.store80 = true;
break;
case 0xC002: // action:W - RAMRD Off: read main 48K bank
this.ramrd = this.bank0;
break;
case 0xC003: // action:W - RAMRD On: read auxiliary 48K bank
this.ramrd = this.bank1;
break;
case 0xC004: // action:W - RAMWRT Off: write to main 48K bank
this.ramwrt = this.bank0;
break;
case 0xC005: // action:W - RAMWRT On: write to auxiliary 48K bank
this.ramwrt = this.bank1;
break;
case 0xC008: // action:W - ALTZP Off: use main 16K bank, page 0 and page 1
this.altzp = this.bank0;
break;
case 0xC00D: // action:W - 80COL Off: display 40 columns
this.col80 = false;
break;
case 0xC00E: // action:W - 80COL On: display 80 columns
this.col80 = true;
break;
case 0xC00E: // action:W - ALTCHAR Off: display text using primary character set
this.altchar = false;
break;
case 0xC00E: // action:W - ALTCHAR On: display text using alternate character set
this.altchar = true;
break;
case 0xC010: // action:W - ALTZP On: use auxiliary 16K bank, page 0 and page 1
this.altzp = this.bank1;
break;
case 0xC050: // action:RW - TXTCLR, display graphics
this.textmode = false;
break;
case 0xC051: // action:RW - TXTSET, display text
this.textmode = true;
break;
case 0xC052: // action:RW - MIXCLR, display full screen
this.mixed = false;
break;
case 0xC053: // action:RW - MIXSET, display split screen
this.mixed = true;
break;
case 0xC054: // action:RW - PAGE2 Off: Select TLP1 and HRP1
this.page2 = this.bank0;
break;
case 0xC055: // action:RW - PAGE2 On: Select TLP2 and HRP2 (or TLP1X and HRP1X if 80STORE on)
this.page2 = this.bank1;
break;
case 0xC056: // action:RW - HIRES Off: Display text and lo resolution page
this.hires = false;
break;
case 0xC057: // action:RW - HIRES On: Display high resolution pages, switch with PAGE2
this.hires = true;
break;
case 0xC05E: // action:RW - DHIRES On: Turn on double high resolution
if (this.iodis) this.dhires = true;
break;
case 0xC05F: // action:RW - DHIRES Off: Turn off double high resolution
if (this.ioudis) this.dhires = false;
break;
case 0xC078:
case 0xC07E: // action:W - IOUDIS On: enable access to DIHRES switch; disable IOU access to $C058-$C05F
this.ioudis = true;
break;
case 0xC079:
case 0xC07F: // action:W - IOUDIS Off: disable access to DIHRES switch; enable IOU access to $C058-$C05F
this.ioudis = false;
break;
default:
}
} else if (addr < 0xD000) {
// I/O Firmware
} else {
// 12K ROM & 16K bank switched RAM
if (! this.nowrite) {
// only take action if write protection is disabled
this.altzp[addr-this.offset] = data;
}
}
};
// Return an 8-bit chuck of data at a given address
AppleIIcMemory.prototype.getData = function(addr) {
var data, ram;
if (addr < 0x0200) {
// Switched zero page and stack: controlled by ALTZP
data = this.altzp[addr];
} else if (addr < 0xC000) {
// 48K bank switched RAM: controlled by RAMRD
ram = this.ramrd;
if (this.store80) {
// 80STORE is enabled: this affects the text page separately
if (addr >= 0x0300 && addr < 0x0700) {
ram = this.page2;
} else if (this.hires && addr >= 0x2000 && add < 0x3F00) {
ram = this.page2;
}
}
data = ram[addr];
} else if (addr < 0xC100) {
// Hardware page
switch(addr) {
case 0xC011: // action:R7 - RDBNK2, read whether $D000 bank 2 (1) or bank 1 (0)
data = (this.offset === 0x1000) << 7;
break;
case 0xC012: // action:R - RDLCRAM, reading RAM (1) or ROM (0)
data = this.enlcram << 7;
break;
case 0xC013: // action:R7 - RDRAMRD, reading auxiliary (1) or main (0) 48K bank
data = (this.ramrd === this.bank1) << 7;
break;
case 0xC014: // action:R7 - RDRAMWRT, writing auxiliary (1) or main (0) 48K bank
data = (this.ramwrt === this.bank1) << 7;
break;
case 0xC017: // action:R7 - RDALTZP, read whether auxiliary (1) or main (0) bank
data = (this.altzp === this.bank1) << 7;
break;
case 0xC018: // action:R7 - RD80STORE, read whether 80STORE is on (1) or off (0);
data = this.store80 << 7;
break;
case 0xC01A: // action:R7 - RDTEXT, read whether TEXT is on (1) or off (0);
data = this.textmode << 7;
break;
case 0xC01B: // action:R7 - RDMIXED, read whether MIXED is on (1) or off (0);
data = this.mixed << 7;
break;
case 0xC01C: // action:R7 - RDPAGE2, read whether PAGE2 is on (1) or off (0);
data = (this.page2 === this.bank1) << 7;
break;
case 0xC01D: // action:R7 - RDHIRES, read whether HIRES is on (1) or off (0);
data = this.hires << 7;
break;
case 0xC01E: // action:R7 - RDALTCHAR, read whether ALTCHAR is on (1) of off (0)
data = this.altchar << 7;
break;
case 0xC01F: // action:R7 - RD80COL, read whether 80COL is on (1) or off (0)
data = this.col80 << 7;
break;
case 0xC050: // action:RW - TXTCLR, display graphics
this.textmode = false;
break;
case 0xC051: // action:RW - TXTSET, display text
this.textmode = true;
break;
case 0xC052: // action:RW - MIXCLR, display full screen
this.mixed = false;
break;
case 0xC053: // action:RW - MIXSET, display split screen
this.mixed = true;
break;
case 0xC054: // action:RW - PAGE2 Off: Select TLP1 and HRP1
this.page2 = this.bank0;
break;
case 0xC055: // action:RW - PAGE2 On: Select TLP2 and HRP2 (or TLP1X and HRP1X if 80STORE on)
this.page2 = this.bank1;
break;
case 0xC056: // action:RW - HIRES Off: Display text and lo resolution page
this.hires = false;
break;
case 0xC057: // action:RW - HIRES On: Display high resolution pages, switch with PAGE2
this.hires = true;
break;
case 0xC05E: // action:RW - DHIRES On: Turn on double high resolution
if (this.ioudis) this.dhires = true;
break;
case 0xC05F: // action:RW - DHIRES Off: Turn off double high resolution
if (this.ioudis) this.dhires = false;
break;
case 0xC07E: // action:R7 - RIOUDIS, read whether IOUDIS is on (0) or off (1)
data = this.ioudis << 7;
break;
case 0xC07F: // action:R7 - RDDHIRES, read whether DHIRES is on (1) or off (0)
data = this.dhires << 7;
break;
case 0xC080: // action:R - read RAM, no write; use $D000 bank 2
this.enlcram = true;
this.offset = 0x1000;
this.nowrite = true;
break;
case 0xC081: // action:RR - read ROM, write RAM; use $D000 bank 2
this.enlcram = false;
this.offset = 0x1000;
this.nowrite = (this.lastRead !== 0xC081);
break;
case 0xC082: // action:R - read ROM, no write; use $D000 bank 2
this.enlcram = false;
this.offset = 0x1000;
this.nowrite = true;
break;
case 0xC083: // action:RR - read and write RAM; use $D000 bank 2
this.enlcram = true;
this.offset = 0x1000;
this.nowrite = (this.lastRead !== 0xC083);
break;
case 0xC088: // action:R - read RAM, no write; use $D000 bank 1
this.enlcram = true;
this.offset = 0x0000;
this.nowrite = true;
break;
case 0xC089: // action:RR - read ROM, write RAM; use $D000 bank 1
this.enlcram = false;
this.offset = 0x0000;
this.nowrite = (this.lastRead !== 0xC089);
break;
case 0xC08A: // action:R - read ROM, no write; use $D000 bank 1
this.enlcram = false;
this.offset = 0x0000;
this.nowrite = true;
break;
case 0xC08B: // action:RR - read and write RAM; use $D000 bank 1
this.enlcram = true;
this.offset = 0x0000;
this.nowrite = (this.lastRead !== 0xC08B);
break;
default:
data = 0x00;
}
} else if (addr < 0xD000) {
// I/O Firmware
} else {
// 12K ROM & 16K bank switched RAM
if (! this.enlcram) {
// Read ROM
data = this.rom[addr - 0xD000];
} else {
data = this.altzp[addr-this.offset];
}
}
this.lastRead = addr;
return data;
};
// Return a 16-bit chuck of data at a given address
AppleIIcMemory.prototype.getAddr = function(addr) {
return this.getData(addr) | this.getData[(addr+1) & 0xFFFF] << 8;
};

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function StatusRegister() {
this.N = false; // bit 7: Negative flag
this.V = false; // bit 6: oVerflow flag
this.R = true; // bit 5: Reserved flag: hardwired to '1'
this.B = false; // bit 4: Break flag
this.D = false; // bit 3: Decimal flag
this.I = false; // bit 2: Interrupt flag
this.Z = false; // bit 1: Zero flag
this.C = false; // bit 0: Carry flag
}
StatusRegister.prototype.get = function() {
return (this.N<<7) + (this.V<<6) + 32 + (this.B<<4) +
(this.D<<3) + (this.I<<2) + (this.Z<<1) + this.C;
};
StatusRegister.prototype.set= function(value) {
this.N = (value & (1<<7)) > 0;
this.V = (value & (1<<6)) > 0;
this.B = (value & (1<<4)) > 0;
this.D = (value & (1<<3)) > 0;
this.I = (value & (1<<2)) > 0;
this.Z = (value & (1<<1)) > 0;
this.C = (value & 1) > 0;
};
function Cpu(memCtrl) {
// Simulates connections to the IRQ and NMI pins. If set to true (HIGH), then
// IRQ or NMI interrupts will be triggered
this.irq_pin = false;
this.nmi_pin = false;
// Interrupt vector addresses; these are hardwired in the CPU
var VECTOR_NMI = 0xFFFA; // non-maskable interrupt
var VECTOR_RST = 0xFFFC; // reset
var VECTOR_IRQ = 0xFFFE; // interrupt request
// Registers
var regA = 0x00; // Accumulator
var regX = 0x00; // X-index register
var regY = 0x00; // Y-index register
var regSP = 0xFF; // Stack pointer
var regPC = 0x00; // Program counter
regSR = new StatusRegister(); // Status register
// State information
var cycle = 0; // CPU cycle counter
var opcode = 0x00; // current opcode
var PCinc = 0x00; // amount to increase PC at end of cycle
var waiting = false; // CPU waiting (due to WAI)
var stopped = false; // CPU halted (due to STP)
// Helper functions
function operandAddr() { // Address of LSB of operand
return (regPC + 1) & 0xFFFF;
}
function updateNZ(data) { // Update the N and Z flags
regSR.Z = (data === 0); // Z flag true if data == 0
regSR.N = (data & 0x80) > 0; // N flag true if bit 7 = 1;
}
function pushStack(data) { // Push data onto stack
var addr = (0x01 << 8) | regSP;
memCtrl.setData(addr, data);
regSP = (regSP - 1) & 0xFF;
}
function pullStack() { // Pull data from stack
regSP = (regSP + 1) & 0xFF;
var addr = (0x01 << 8) | regSP;
return memCtrl.getData(addr);
}
function pushStackAddr(addr) { // Push 16-bit address onto stack
pushStack((addr & 0xFF00) >> 8); // push high byte
pushStack(addr & 0x00FF); // push low byte
}
function pullStackAddr() { // Pull 16-bit address from stack
var lo = pullStack(); // pull low byte
var hi = pullStack(); // pull high byte
return lo + (hi << 8);
}
function checkBranch(addr, condition) { // check if we can do a branch
if (condition) {
// do the branch
cycle++;
if ((regPC & 0xFF00) != (addr & 0xFF00))
cycle++; // add a cycle if PB crossed
regPC = addr;
}
}
// Cycle lookup table
var opcycles =
[7, 6, 2, 1, 5, 3, 5, 5, 3, 2, 2, 1, 6, 4, 6, 5,
2, 5, 5, 1, 5, 4, 6, 5, 2, 4, 2, 1, 6, 4, 6, 5,
6, 6, 2, 1, 3, 3, 5, 5, 4, 2, 2, 1, 4, 4, 6, 5,
2, 5, 5, 1, 4, 4, 6, 5, 2, 4, 2, 1, 4, 4, 6, 5,
6, 6, 2, 1, 3, 3, 5, 5, 3, 2, 2, 1, 3, 4, 6, 5,
2, 5, 5, 1, 4, 4, 6, 5, 2, 4, 3, 1, 8, 4, 6, 5,
6, 6, 2, 1, 3, 3, 5, 5, 4, 2, 2, 1, 6, 4, 6, 5,
2, 5, 5, 1, 4, 4, 6, 5, 2, 4, 4, 1, 6, 4, 6, 5,
3, 6, 2, 1, 3, 3, 3, 5, 2, 2, 2, 1, 4, 4, 4, 5,
2, 6, 5, 1, 4, 4, 4, 5, 2, 5, 2, 1, 4, 5, 5, 5,
2, 6, 2, 1, 3, 3, 3, 5, 2, 2, 2, 1, 4, 4, 4, 5,
2, 5, 5, 1, 4, 4, 4, 5, 2, 4, 2, 1, 4, 4, 4, 5,
2, 6, 2, 1, 3, 3, 5, 5, 2, 2, 2, 3, 4, 4, 6, 5,
2, 5, 5, 1, 4, 4, 6, 5, 2, 4, 3, 3, 4, 4, 7, 5,
2, 6, 2, 1, 3, 3, 5, 5, 2, 2, 2, 1, 4, 4, 6, 5,
2, 5, 5, 1, 4, 4, 6, 5, 2, 4, 4, 1, 4, 4, 7, 5];
/** Implicit addressing
* Address is implicit in operand
* e.g. RTS
* 0 bytes
*/
var amImplicit = function() {
return regPC;
};
/** Accumulator addressing
* Use accumulator for data
* e.g. ASL A
* 0 bytes
*/
var amAccumulator = function() {
return regPC;
};
/** Immediate Mode addressing
* Address immediately follows opcode
* e.g. LDA #$65
* 1 byte
*/
var amImmediate = function() {
PCinc++;
return (regPC + 1) & 0xFFFF;
};
/** Zero Page addressing
* Zero page address is formed by taking next 8-bit value
* e.g. LDA $4F
* 1 byte
*/
var amZeroPage = function() {
PCinc++;
return memCtrl.getData(operandAddr());
};
/** Zero Page, X addressing
* Zero page address is formed by taking next 8-bit value and
* adding X to it. Address wraps around page $00
* e.g. LDA $65,X
* 1 byte
*/
var amZeroPageX = function() {
PCinc++;
return (memCtrl.getData(operandAddr()) + regX) & 0x00FF;
};
/** Zero Page, Y addressing
* Zero page address is formed by taking next 8-bit value and
* adding Y to it. Address wraps around page $00
* e.g. LDA $5C,Y
* 1 byte
*/
var amZeroPageY = function() {
PCinc++;
return (memCtrl.getData(operandAddr()) + regY) & 0x00FF;
};
/** Zero Page Indirect addressing
* Address is formed by taking zero page address from next 8-bit value
* Zero page location is LSB of 16-bit address. Wrap around occurs.
* e.g. LDA ($23)
* 1 byte
*/
var amZPIndirect = function() {
PCinc++;
var addr = memCtrl.getData(operandAddr());
return memCtrl.getData(addr) + (memCtrl.getData(addr+1 & 0x00FF) << 8);
};
/** Zero Page Indirect, X addressing
* Address is formed by taking zero page address from next 8-bit value
* and adding X to it (with wrap around).
* Zero page location is LSB of 16-bit address. Wrap around occurs.
* e.g. LDA ($D2,X)
* 1 byte
*/
var amZPIndirectX = function() {
PCinc++;
var addr = (memCtrl.getData(operandAddr()) + regX) & 0x00FF;
return memCtrl.getData(addr) + (memCtrl.getData(addr+1 & 0x00FF) << 8);
};
/** Zero Page Indirect, Y addressing
* Address is formed by taking zero page address from next 8-bit value
* Zero page location is LSB of 16-bit address. Y is added to this value
* e.g. LDA ($C1),Y
* 1 byte, +1 cycle if PB crossed
*/
var amZPIndirectY = function() {
PCinc++;
var zp_addr = memCtrl.getData(operandAddr());
var ind_addr = memCtrl.getData(zp_addr) + (memCtrl.getData((zp_addr+1) & 0x00FF) << 8);
var addr = (ind_addr + regY) & 0xFFFF;
// check if PB is crossed
if ((addr & 0xFF00) != (ind_addr & 0xFF00)) { cycle++; }
return addr;
};
/** Zero Page Relative addressing
* Zero page address is given by the next 8-bit value, and the 8-bit value
* that follows is a signed offset (-128 -> +127)
* e.g. BBR0 $23,12
* 2 bytes
*/
var amZPRelative = function() {
PCinc += 2;
return memCtrl.getData(operandAddr());
};
/** Relative addressing
* Signed offset (-128 -> +127) is given by the next 8-bit value
* e.g. BEQ -34
* 1 byte
*/
var amRelative = function() {
PCinc++;
var offset = memCtrl.getData(operandAddr());
if (offset > 127) {
return (regPC + (offset - 256)) & 0xFFFF;
} else {
return (regPC + offset) & 0xFFFF;
}
};
/** Absolute addressing
* Located at address pointed to by next 16-bit memory value
* e.g. JMP $872F
* 2 bytes
*/
var amAbsolute = function() {
PCinc += 2;
return memCtrl.getAddr(operandAddr());
};
/** Absolute, X addressing
* Address is formed by taking next 16-bit memory value, and
* adding X to it
* e.g. JMP $1291,X
* 2 bytes, +1 cycle if PB crossed
*/
var amAbsoluteX = function() {
PCinc += 2;
var base_addr = memCtrl.getAddr(operandAddr());
var addr = (base_addr + regX) & 0xFFFF;
// check if PB is crossed (except for DEC and INC - new for 65C02)
if (((addr & 0xFF00) != (base_addr & 0xFF00)) &&
(opcode != 0xDE && 0xFE)) { cycle++; }
return addr;
};
/** Absolute, Y addressing
* Address is formed by taking next 16-bit memory value, and
* adding Y to it
* e.g. JMP $C123,Y
* 2 bytes, +1 cycle if PB crossed
*/
var amAbsoluteY = function() {
PCinc += 2;
var base_addr = memCtrl.getAddr(operandAddr());
var addr = (base_addr + regY) & 0xFFFF;
// check if PB is crossed
if ((addr & 0xFF00) != (base_addr & 0xFF00)) { cycle++; }
return addr;
};
/** Absolute Indirect addressing
* Next 16-bits are the address of another address
* e.g. JMP ($4C21)
* 2 bytes
*/
var amIndirect = function() {
PCinc += 2;
var addr = memCtrl.getAddr(operandAddr());
return memCtrl.getAddr(addr);
};
/** Absolute Indirect Indexed addressing
* Next 16-bits are added to X, which point to another address
* e.g. JMP ($0823,X)
* 2 bytes
*/
var amAbsIndIndx = function() {
PCinc += 2; cycle += 5;
var addr = (memCtrl.getAddr(operandAddr()) + regX) & 0xFFFF;
return memCtrl.getAddr(addr);
};
// Opcode functions
var opLDA = function(amFn) { regA = memCtrl.getData(amFn()); updateNZ(regA); };
var opLDX = function(amFn) { regX = memCtrl.getData(amFn()); updateNZ(regX); };
var opLDY = function(amFn) { regY = memCtrl.getData(amFn()); updateNZ(regY); };
var opSTA = function(amFn) { memCtrl.setData(amFn(), regA); };
var opSTX = function(amFn) { memCtrl.setData(amFn(), regX); };
var opSTY = function(amFn) { memCtrl.setData(amFn(), regY); };
var opSTZ = function(amFn) { memCtrl.setData(amFn(), 0x00); };
var opPHA = function(amFn) { pushStack(regA); };
var opPHX = function(amFn) { pushStack(regX); };
var opPHY = function(amFn) { pushStack(regY); };
var opPHP = function(amFn) { regSR.B = true; pushStack(regSR.get()); };
var opPLA = function(amFn) { regA = pullStack(); updateNZ(regA); };
var opPLX = function(amFn) { regX = pullStack(); updateNZ(regX); };
var opPLY = function(amFn) { regY = pullStack(); updateNZ(regY); };
var opPLP = function(amFn) { regSR.set(pullStack()); regSR.B = true; };
var opTSX = function(amFn) { regX = regSP; updateNZ(regX); };
var opTXS = function(amFn) { regSP = regX; };
var opINA = function(amFn) { regA = (regA+1) & 0xFF; updateNZ(regA); };
var opINX = function(amFn) { regX = (regX+1) & 0xFF; updateNZ(regX); };
var opINY = function(amFn) { regY = (regY+1) & 0xFF; updateNZ(regY); };
var opDEA = function(amFn) { regA = (regA-1) & 0xFF; updateNZ(regA); };
var opDEX = function(amFn) { regX = (regX-1) & 0xFF; updateNZ(regX); };
var opDEY = function(amFn) { regY = (regY-1) & 0xFF; updateNZ(regY); };
var opINC = function(amFn) {
var addr = amFn();
var data = memCtrl.getData(addr); // retrieve data from memory
data = memCtrl.getData(addr); // 2nd mem read (new for 65C02)
data = (data + 1) & 0xFF;
memCtrl.setData(addr, data);
updateNZ(data);
};
var opDEC = function(amFn) {
var addr = amFn();
var data = memCtrl.getData(addr); // retrieve data from memory
data = memCtrl.getData(addr); // 2nd mem read (new for 65C02)
data = (data - 1) & 0xFF;
memCtrl.setData(addr, data);
updateNZ(data);
};
var opASL = function(amFn) {
var addr = amFn();
var data = memCtrl.getData(addr); // retrieve data from memory
data = memCtrl.getData(addr); // 2nd mem read (new for 65C02)
regSR.C = (data & 0x80) > 0; // Get the high bit and put it in the carry flag
data = (data << 1) & 0xFF; // shift left and mask
memCtrl.setData(addr, data);
updateNZ(data);
};
var opASL_A = function(amFn) {
regSR.C = (regA & 0x80) > 0;
regA = (regA << 1) & 0xFF;
updateNZ(regA);
};
var opLSR = function(amFn) {
var addr = amFn();
var data = memCtrl.getData(addr); // retrieve data from memory
data = memCtrl.getData(addr); // 2nd mem read (new for 65C02)
regSR.C = (data & 0x01) > 0; // get the low bit and put it in the carry flag
data = (data >> 1) & 0xFF; // shift right and mask
memCtrl.setData(addr, data);
updateNZ(data);
};
var opLSR_A = function(amFn) {
regSR.C = (regA & 0x01) > 0;
regA = (regA >> 1) & 0xFF;
updateNZ(regA);
};
var opROL = function(amFn) {
var addr = amFn();
var data = memCtrl.getData(addr); // retrieve data from memory
data = memCtrl.getData(addr); // 2nd mem read (new for 65C02)
data = (data << 1) | regSR.C; // shift left and add the carry bit
regSR.C = (data & 0x100) > 0; // get bit-8 and put it in the carry flag
data &= 0xFF; // mask the data
memCtrl.setData(addr, data);
updateNZ(data);
};
var opROL_A = function(amFn) {
regA = (regA << 1) | regSR.C;
regSR.C = (regA & 0x100) > 0;
regA &= 0xFF;
updateNZ(regA);
};
var opROR = function(amFn) {
var addr = amFn();
var data = memCtrl.getData(addr); // retrieve data from memory
data = memCtrl.getData(addr); // 2nd mem read (new for 65C02)
var newC = (data & 0x01) > 0; // get new Carry flag from bit 1
data = (data | (regSR.C << 8)) >> 1; // add existing Carry flag and shift right
data &= 0xFF; // mask the data
regSR.C = newC; // set the Carry flag
memCtrl.setData(addr, data);
updateNZ(data);
};
var opROR_A = function(amFn) {
var newC = (regA & 0x01) > 0;
regA = (regA | (regSR.C << 8)) >> 1;
regA &= 0xFF;
regSR.C = newC;
updateNZ(regA);
};
var opAND = function(amFn) { regA = (regA & memCtrl.getData(amFn())) & 0xFF; updateNZ(regA); };
var opORA = function(amFn) { regA = (regA | memCtrl.getData(amFn())) & 0xFF; updateNZ(regA); };
var opEOR = function(amFn) { regA = (regA ^ memCtrl.getData(amFn())) & 0xFF; updateNZ(regA); };
var opBIT = function(amFn) {
var data = memCtrl.getData(amFn());
var result = data & regA;
regSR.Z = (result === 0x00);
if (opcode != 0x89) { // new for 65C02: immediate mode does not affect V and N flags
regSR.V = (data & 0x40) > 0;
regSR.N = (data & 0x80) > 0;
}
};
var opCMP = function(amFn) {
var data = memCtrl.getData(amFn());
regSR.C = (regA >= data);
updateNZ((regA - data) & 0xFF);
};
var opCPX = function(amFn) {
var data = memCtrl.getData(amFn());
regSR.C = (regX >= data);
updateNZ((regX - data) & 0xFF);
};
var opCPY = function(amFn) {
var data = memCtrl.getData(amFn());
regSR.C = (regY >= data);
updateNZ((regY - data) & 0xFF);
};
var opTRB = function(amFn) {
var addr = amFn();
var data = memCtrl.getData(addr);
var result = data & (regA ^ 0xFF);
regSR.Z = (regA & data) === 0;
memCtrl.setData(addr, result);
};
var opTSB = function(amFn) {
var addr = amFn();
var data = memCtrl.getData(addr);
var result = data | regA;
regSR.Z = (regA & data) === 0;
memCtrl.setData(addr, result);
};
var opRMB = function(amFn) {
var addr = amFn();
var bitmask = 1 << (opcode >> 4);
var result = memCtrl.getData(addr) & (bitmask ^ 0xFF);
memCtrl.setData(addr, result);
};
var opSMB = function(amFn) {
var addr = amFn();
var bitmask = 1 << ((opcode >> 4) - 8);
var result = memCtrl.getData(addr) | bitmask;
memCtrl.setData(addr, result);
};
var opADC = function(amFn) {
var data = memCtrl.getData(amFn());
var result;
if (!regSR.D) {
result = regA + data + regSR.C;
} else {
cycle++; // new for 65C02 to make flags in D mode correct
result = (regA & 0x0F) + (data & 0x0F) + regSR.C;
if (result >= 0x0A) { result = ((result + 0x06) & 0x0F) + 0x10; }
result = (regA & 0xF0) + (data & 0xF0) + result;
if (result >= 0xA0) { result += 0x60; }
}
regSR.C = (result & 0x100) > 0;
result &= 0xFF;
regSR.V = ((regA^result)&(data^result)&0x80) > 0;
regA = result;
updateNZ(regA);
};
var opSBC = function(amFn) {
var data = memCtrl.getData(amFn());
var result;
if (!regSR.D) {
result = regA - data - (1 - regSR.C);
} else {
cycle++; // new for 65C02 to make flags in D mode correct
result = (regA & 0x0F) - (data & 0x0F) - (1 - regSR.C);
if (result < 0) {result = ((result - 0x06) & 0x0F) - 0x10; }
result = (regA & 0xF0) - (data & 0xF0) + result;
if (result < 0) {result -= 0x60; }
}
regSR.C = (result >= 0);
result &= 0xFF;
regSR.V = ((regA^result)&((255-data)^result)&0x80) > 0;
regA = result;
updateNZ(regA);
};
var opJMP = function(amFn) { regPC = amFn(); PCinc = 0; };
var opJSR = function(amFn) { pushStackAddr((regPC+2) & 0xFFFF); regPC = amFn(); PCinc = 0;};
var opRTS = function(amFn) { regPC = pullStackAddr(); };
var opRTI = function(amFn) { this.regSR.set(pullStack()); regSR.B = true; regPC = pullStackAddr(); PCinc = 0;};
var opBRA = function(amFn) { regPC = amFn(); };
var opBEQ = function(amFn) { checkBranch(amFn(), regSR.Z); };
var opBNE = function(amFn) { checkBranch(amFn(), !regSR.Z); };
var opBCC = function(amFn) { checkBranch(amFn(), !regSR.C); };
var opBCS = function(amFn) { checkBranch(amFn(), regSR.C); };
var opBVC = function(amFn) { checkBranch(amFn(), !regSR.V); };
var opBVS = function(amFn) { checkBranch(amFn(), regSR.V); };
var opBMI = function(amFn) { checkBranch(amFn(), regSR.N); };
var opBPL = function(amFn) { checkBranch(amFn(), !regSR.N); };
var opBBR = function(amFn) {
var bitmask = 1 << (opcode >> 4);
if ((memCtrl.getData(amFn()) & bitmask) === 0) {
var offset = memCtrl.getData((regPC+2) & 0xFFFF);
if (offset > 127) {
regPC = (regPC + (offset - 256)) & 0xFFFF;
} else {
regPC = (regPC + offset) & 0xFFFF;
}
}
};
var opBBS = function(amFn) {
var bitmask = 1 << ((opcode >> 4) - 8);
if ((memCtrl.getData(amFn()) & bitmask) > 0) {
var offset = memCtrl.getData((regPC+2) & 0xFFFF);
if (offset > 127) {
regPC = (regPC + (offset - 256)) & 0xFFFF;
} else {
regPC = (regPC + offset) & 0xFFFF;
}
}
};
var opCLC = function(amFn) { regSR.C = false; };
var opCLD = function(amFn) { regSR.D = false; };
var opCLI = function(amFn) { regSR.I = false; };
var opCLV = function(amFn) { regSR.V = false; };
var opSEC = function(amFn) { regSR.C = true; };
var opSED = function(amFn) { regSR.D = true; };
var opSEI = function(amFn) { regSR.I = true; };
var opTAX = function(amFn) { regX = regA; updateNZ(regX); };
var opTAY = function(amFn) { regY = regA; updateNZ(regY); };
var opTXA = function(amFn) { regA = regX; updateNZ(regA); };
var opTYA = function(amFn) { regA = regY; updateNZ(regA); };
var opNOP = function(amFn) {
// Different NOP instructions have different byte sizes
// PCinc = 1 by default. This switch statements targets NOPs
// with byte sizes greater than 1
switch (opcode & 0x0F) {
case 0x02:
case 0x04:
PCinc = 2;
break;
case 0x0C:
PCinc = 3;
break;
default:
PCinc = 1;
}
};
var opBRK = function(amFn) {
pushStackAddr(regPC+2); // push PC plus 2 (making BRK a 2-byte instruction)
regSR.B = true;
pushStack(regSR.get()); // push SR with B flag set
regSR.I = true; // set I flag
regSR.D = false; // clear D flag before jumping (new for 65C02)
regPC = memCtrl.getAddr(VECTOR_IRQ);
PCinc = 0;
};
var opWAI = function(amFn) {
regSR.B = true;
waiting = true;
};
var opSTP = function(amFn) {
stopped = true;
waiting = true;
};
// opcode <-> address mode lookup table
this.optable = new Array(256);
this.optable[0x00] = function() {opBRK(amImplicit);};
this.optable[0x01] = function() {opORA(amZPIndirectX);};
this.optable[0x02] = function() {opNOP(amImplicit);};
this.optable[0x03] = function() {opNOP(amImplicit);};
this.optable[0x04] = function() {opTSB(amZeroPage);};
this.optable[0x05] = function() {opORA(amZeroPage);};
this.optable[0x06] = function() {opASL(amZeroPage);};
this.optable[0x07] = function() {opRMB(amZeroPage);};
this.optable[0x08] = function() {opPHP(amImplicit);};
this.optable[0x09] = function() {opORA(amImmediate);};
this.optable[0x0A] = function() {opASL_A(amAccumulator);};
this.optable[0x0B] = function() {opNOP(amImplicit);};
this.optable[0x0C] = function() {opTSB(amAbsolute);};
this.optable[0x0D] = function() {opORA(amAbsolute);};
this.optable[0x0E] = function() {opASL(amAbsolute);};
this.optable[0x0F] = function() {opBBR(amZPRelative);};
this.optable[0x10] = function() {opBPL(amRelative);};
this.optable[0x11] = function() {opORA(amZPIndirectY);};
this.optable[0x12] = function() {opORA(amZPIndirect);};
this.optable[0x13] = function() {opNOP(amImplicit);};
this.optable[0x14] = function() {opTRB(amZeroPage);};
this.optable[0x15] = function() {opORA(amZeroPageX);};
this.optable[0x16] = function() {opASL(amZeroPageX);};
this.optable[0x17] = function() {opRMB(amZeroPage);};
this.optable[0x18] = function() {opCLC(amImplicit);};
this.optable[0x19] = function() {opORA(amAbsoluteY);};
this.optable[0x1A] = function() {opINA(amImplicit);};
this.optable[0x1B] = function() {opNOP(amImplicit);};
this.optable[0x1C] = function() {opTRB(amAbsolute);};
this.optable[0x1D] = function() {opORA(amAbsoluteX);};
this.optable[0x1E] = function() {opASL(amAbsoluteX);};
this.optable[0x1F] = function() {opBBR(amZPRelative);};
this.optable[0x20] = function() {opJSR(amAbsolute);};
this.optable[0x21] = function() {opAND(amZPIndirectX);};
this.optable[0x22] = function() {opNOP(amImplicit);};
this.optable[0x23] = function() {opNOP(amImplicit);};
this.optable[0x24] = function() {opBIT(amZeroPage);};
this.optable[0x25] = function() {opAND(amZeroPage);};
this.optable[0x26] = function() {opROL(amZeroPage);};
this.optable[0x27] = function() {opRMB(amZeroPage);};
this.optable[0x28] = function() {opPLP(amImplicit);};
this.optable[0x29] = function() {opAND(amImmediate);};
this.optable[0x2A] = function() {opROL_A(amAccumulator);};
this.optable[0x2B] = function() {opNOP(amImplicit);};
this.optable[0x2C] = function() {opBIT(amAbsolute);};
this.optable[0x2D] = function() {opAND(amAbsolute);};
this.optable[0x2E] = function() {opROL(amAbsolute);};
this.optable[0x2F] = function() {opBBR(amZPRelative);};
this.optable[0x30] = function() {opBMI(amRelative);};
this.optable[0x31] = function() {opAND(amZPIndirectY);};
this.optable[0x32] = function() {opAND(amZPIndirect);};
this.optable[0x33] = function() {opNOP(amImplicit);};
this.optable[0x34] = function() {opBIT(amZeroPageX);};
this.optable[0x35] = function() {opAND(amZeroPageX);};
this.optable[0x36] = function() {opROL(amZeroPageX);};
this.optable[0x37] = function() {opRMB(amZeroPage);};
this.optable[0x38] = function() {opSEC(amImplicit);};
this.optable[0x39] = function() {opAND(amAbsoluteY);};
this.optable[0x3A] = function() {opDEA(amImplicit);};
this.optable[0x3B] = function() {opNOP(amImplicit);};
this.optable[0x3C] = function() {opBIT(amAbsoluteX);};
this.optable[0x3D] = function() {opAND(amAbsoluteX);};
this.optable[0x3E] = function() {opROL(amAbsoluteX);};
this.optable[0x3F] = function() {opBBR(amZPRelative);};
this.optable[0x40] = function() {opRTI(amImplicit);};
this.optable[0x41] = function() {opEOR(amZPIndirectX);};
this.optable[0x42] = function() {opNOP(amImplicit);};
this.optable[0x43] = function() {opNOP(amImplicit);};
this.optable[0x44] = function() {opNOP(amImplicit);};
this.optable[0x45] = function() {opEOR(amZeroPage);};
this.optable[0x46] = function() {opLSR(amZeroPage);};
this.optable[0x47] = function() {opRMB(amZeroPage);};
this.optable[0x48] = function() {opPHA(amImplicit);};
this.optable[0x49] = function() {opEOR(amImmediate);};
this.optable[0x4A] = function() {opLSR_A(amAccumulator);};
this.optable[0x4B] = function() {opNOP(amImplicit);};
this.optable[0x4C] = function() {opJMP(amAbsolute);};
this.optable[0x4D] = function() {opEOR(amAbsolute);};
this.optable[0x4E] = function() {opLSR(amAbsolute);};
this.optable[0x4F] = function() {opBBR(amZPRelative);};
this.optable[0x50] = function() {opBVC(amRelative);};
this.optable[0x51] = function() {opEOR(amZPIndirectY);};
this.optable[0x52] = function() {opEOR(amZPIndirect);};
this.optable[0x53] = function() {opNOP(amImplicit);};
this.optable[0x54] = function() {opNOP(amImplicit);};
this.optable[0x55] = function() {opEOR(amZeroPageX);};
this.optable[0x56] = function() {opLSR(amZeroPageX);};
this.optable[0x57] = function() {opRMB(amZeroPage);};
this.optable[0x58] = function() {opCLI(amImplicit);};
this.optable[0x59] = function() {opEOR(amAbsoluteY);};
this.optable[0x5A] = function() {opPHY(amImplicit);};
this.optable[0x5B] = function() {opNOP(amImplicit);};
this.optable[0x5C] = function() {opNOP(amImplicit);};
this.optable[0x5D] = function() {opEOR(amAbsoluteX);};
this.optable[0x5E] = function() {opLSR(amAbsoluteX);};
this.optable[0x5F] = function() {opBBR(amZPRelative);};
this.optable[0x60] = function() {opRTS(amImplicit);};
this.optable[0x61] = function() {opADC(amZPIndirectX);};
this.optable[0x62] = function() {opNOP(amImplicit);};
this.optable[0x63] = function() {opNOP(amImplicit);};
this.optable[0x64] = function() {opSTZ(amZeroPage);};
this.optable[0x65] = function() {opADC(amZeroPage);};
this.optable[0x66] = function() {opROR(amZeroPage);};
this.optable[0x67] = function() {opRMB(amZeroPage);};
this.optable[0x68] = function() {opPLA(amImplicit);};
this.optable[0x69] = function() {opADC(amImmediate);};
this.optable[0x6A] = function() {opROR_A(amAccumulator);};
this.optable[0x6B] = function() {opNOP(amImplicit);};
this.optable[0x6C] = function() {opJMP(amIndirect);};
this.optable[0x6D] = function() {opADC(amAbsolute);};
this.optable[0x6E] = function() {opROR(amAbsolute);};
this.optable[0x6F] = function() {opBBR(amZPRelative);};
this.optable[0x70] = function() {opBVS(amRelative);};
this.optable[0x71] = function() {opADC(amZPIndirectY);};
this.optable[0x72] = function() {opADC(amZPIndirect);};
this.optable[0x73] = function() {opNOP(amImplicit);};
this.optable[0x74] = function() {opSTZ(amZeroPageX);};
this.optable[0x75] = function() {opADC(amZeroPageX);};
this.optable[0x76] = function() {opROR(amZeroPageX);};
this.optable[0x77] = function() {opRMB(amZeroPage);};
this.optable[0x78] = function() {opSEI(amImplicit);};
this.optable[0x79] = function() {opADC(amAbsoluteY);};
this.optable[0x7A] = function() {opPLY(amImplicit);};
this.optable[0x7B] = function() {opNOP(amImplicit);};
this.optable[0x7C] = function() {opJMP(amAbsIndIndx);};
this.optable[0x7D] = function() {opADC(amAbsoluteX);};
this.optable[0x7E] = function() {opROR(amAbsoluteX);};
this.optable[0x7F] = function() {opBBR(amZPRelative);};
this.optable[0x80] = function() {opBRA(amRelative);};
this.optable[0x81] = function() {opSTA(amZPIndirectX);};
this.optable[0x82] = function() {opNOP(amImplicit);};
this.optable[0x83] = function() {opNOP(amImplicit);};
this.optable[0x84] = function() {opSTY(amZeroPage);};
this.optable[0x85] = function() {opSTA(amZeroPage);};
this.optable[0x86] = function() {opSTX(amZeroPage);};
this.optable[0x87] = function() {opSMB(amZeroPage);};
this.optable[0x88] = function() {opDEY(amImplicit);};
this.optable[0x89] = function() {opBIT(amImmediate);};
this.optable[0x8A] = function() {opTXA(amImplicit);};
this.optable[0x8B] = function() {opNOP(amImplicit);};
this.optable[0x8C] = function() {opSTY(amAbsolute);};
this.optable[0x8D] = function() {opSTA(amAbsolute);};
this.optable[0x8E] = function() {opSTX(amAbsolute);};
this.optable[0x8F] = function() {opBBS(amZPRelative);};
this.optable[0x90] = function() {opBCC(amRelative);};
this.optable[0x91] = function() {opSTA(amZPIndirectY);};
this.optable[0x92] = function() {opSTA(amZPIndirect);};
this.optable[0x93] = function() {opNOP(amImplicit);};
this.optable[0x94] = function() {opSTY(amZeroPageX);};
this.optable[0x95] = function() {opSTA(amZeroPageX);};
this.optable[0x96] = function() {opSTX(amZeroPageY);};
this.optable[0x97] = function() {opSMB(amZeroPage);};
this.optable[0x98] = function() {opTYA(amImplicit);};
this.optable[0x99] = function() {opSTA(amAbsoluteY);};
this.optable[0x9A] = function() {opTXS(amImplicit);};
this.optable[0x9B] = function() {opNOP(amImplicit);};
this.optable[0x9C] = function() {opSTZ(amAbsolute);};
this.optable[0x9D] = function() {opSTA(amAbsoluteX);};
this.optable[0x9E] = function() {opSTZ(amAbsoluteX);};
this.optable[0x9F] = function() {opBBS(amZPRelative);};
this.optable[0xA0] = function() {opLDY(amImmediate);};
this.optable[0xA1] = function() {opLDA(amZPIndirectX);};
this.optable[0xA2] = function() {opLDX(amImmediate);};
this.optable[0xA3] = function() {opNOP(amImplicit);};
this.optable[0xA4] = function() {opLDY(amZeroPage);};
this.optable[0xA5] = function() {opLDA(amZeroPage);};
this.optable[0xA6] = function() {opLDX(amZeroPage);};
this.optable[0xA7] = function() {opSMB(amZeroPage);};
this.optable[0xA8] = function() {opTAY(amImplicit);};
this.optable[0xA9] = function() {opLDA(amImmediate);};
this.optable[0xAA] = function() {opTAX(amImplicit);};
this.optable[0xAB] = function() {opNOP(amImplicit);};
this.optable[0xAC] = function() {opLDY(amAbsolute);};
this.optable[0xAD] = function() {opLDA(amAbsolute);};
this.optable[0xAE] = function() {opLDX(amAbsolute);};
this.optable[0xAF] = function() {opBBS(amZPRelative);};
this.optable[0xB0] = function() {opBCS(amRelative);};
this.optable[0xB1] = function() {opLDA(amZPIndirectY);};
this.optable[0xB2] = function() {opLDA(amZPIndirect);};
this.optable[0xB3] = function() {opNOP(amImplicit);};
this.optable[0xB4] = function() {opLDY(amZeroPageX);};
this.optable[0xB5] = function() {opLDA(amZeroPageX);};
this.optable[0xB6] = function() {opLDX(amZeroPageY);};
this.optable[0xB7] = function() {opSMB(amZeroPage);};
this.optable[0xB8] = function() {opCLV(amImplicit);};
this.optable[0xB9] = function() {opLDA(amAbsoluteY);};
this.optable[0xBA] = function() {opTSX(amImplicit);};
this.optable[0xBB] = function() {opNOP(amImplicit);};
this.optable[0xBC] = function() {opLDY(amAbsoluteX);};
this.optable[0xBD] = function() {opLDA(amAbsoluteX);};
this.optable[0xBE] = function() {opLDX(amAbsoluteY);};
this.optable[0xBF] = function() {opBBS(amZPRelative);};
this.optable[0xC0] = function() {opCPY(amImmediate);};
this.optable[0xC1] = function() {opCMP(amZPIndirectX);};
this.optable[0xC2] = function() {opNOP(amImplicit);};
this.optable[0xC3] = function() {opNOP(amImplicit);};
this.optable[0xC4] = function() {opCPY(amZeroPage);};
this.optable[0xC5] = function() {opCMP(amZeroPage);};
this.optable[0xC6] = function() {opDEC(amZeroPage);};
this.optable[0xC7] = function() {opSMB(amZeroPage);};
this.optable[0xC8] = function() {opINY(amImplicit);};
this.optable[0xC9] = function() {opCMP(amImmediate);};
this.optable[0xCA] = function() {opDEX(amImplicit);};
this.optable[0xCB] = function() {opWAI(amImplicit);};
this.optable[0xCC] = function() {opCPY(amAbsolute);};
this.optable[0xCD] = function() {opCMP(amAbsolute);};
this.optable[0xCE] = function() {opDEC(amAbsolute);};
this.optable[0xCF] = function() {opBBS(amZPRelative);};
this.optable[0xD0] = function() {opBNE(amRelative);};
this.optable[0xD1] = function() {opCMP(amZPIndirectY);};
this.optable[0xD2] = function() {opCMP(amZPIndirect);};
this.optable[0xD3] = function() {opNOP(amImplicit);};
this.optable[0xD4] = function() {opNOP(amImplicit);};
this.optable[0xD5] = function() {opCMP(amZeroPageX);};
this.optable[0xD6] = function() {opDEC(amZeroPageX);};
this.optable[0xD7] = function() {opSMB(amZeroPage);};
this.optable[0xD8] = function() {opCLD(amImplicit);};
this.optable[0xD9] = function() {opCMP(amAbsoluteY);};
this.optable[0xDA] = function() {opPHX(amImplicit);};
this.optable[0xDB] = function() {opSTP(amImplicit);};
this.optable[0xDC] = function() {opNOP(amImplicit);};
this.optable[0xDD] = function() {opCMP(amAbsoluteX);};
this.optable[0xDE] = function() {opDEC(amAbsoluteX);};
this.optable[0xDF] = function() {opBBS(amZPRelative);};
this.optable[0xE0] = function() {opCPX(amImmediate);};
this.optable[0xE1] = function() {opSBC(amZPIndirectX);};
this.optable[0xE2] = function() {opNOP(amImplicit);};
this.optable[0xE3] = function() {opNOP(amImplicit);};
this.optable[0xE4] = function() {opCPX(amZeroPage);};
this.optable[0xE5] = function() {opSBC(amZeroPage);};
this.optable[0xE6] = function() {opINC(amZeroPage);};
this.optable[0xE7] = function() {opSMB(amZeroPage);};
this.optable[0xE8] = function() {opINX(amImplicit);};
this.optable[0xE9] = function() {opSBC(amImmediate);};
this.optable[0xEA] = function() {opNOP(amImplicit);};
this.optable[0xEB] = function() {opNOP(amImplicit);};
this.optable[0xEC] = function() {opCPX(amAbsolute);};
this.optable[0xED] = function() {opSBC(amAbsolute);};
this.optable[0xEE] = function() {opINC(amAbsolute);};
this.optable[0xEF] = function() {opBBS(amZPRelative);};
this.optable[0xF0] = function() {opBEQ(amRelative);};
this.optable[0xF1] = function() {opSBC(amZPIndirectY);};
this.optable[0xF2] = function() {opSBC(amZPIndirect);};
this.optable[0xF3] = function() {opNOP(amImplicit);};
this.optable[0xF4] = function() {opNOP(amImplicit);};
this.optable[0xF5] = function() {opSBC(amZeroPageX);};
this.optable[0xF6] = function() {opINC(amZeroPageX);};
this.optable[0xF7] = function() {opSMB(amZeroPage);};
this.optable[0xF8] = function() {opSED(amImplicit);};
this.optable[0xF9] = function() {opSBC(amAbsoluteY);};
this.optable[0xFA] = function() {opPLX(amImplicit);};
this.optable[0xFB] = function() {opNOP(amImplicit);};
this.optable[0xFC] = function() {opNOP(amImplicit);};
this.optable[0xFD] = function() {opSBC(amAbsoluteX);};
this.optable[0xFE] = function() {opINC(amAbsoluteX);};
this.optable[0xFF] = function() {opBBS(amZPRelative);};
// CPU Execution Functions
// Run the CPU for a given number of cycles
var run = function(num_cycles) {
var final_cycle = cycle + num_cycles;
// Check for overflow
if (final_cycle < cycle) {
cycle = 0;
final_cycle = num_cycles;
}
while (cycle <= final_cycle && !stopped) {
// handle interrupts
if (this.irq_pin) { this.irq(); if (cycle > final_cycle) return; }
if (this.nmi_pin) { this.nmi(); if (cycle > final_cycle) return; }
if (waiting) return;
opcode = memCtrl.getData(regPC);
PCinc = 1;
cycle += opcycles[opcode];
// Get the opcode function and addressing mode function from the lookup table
optable[opcode]();
regPC = (regPC + PCinc) & 0xFFFF;
}
};
// Reset the CPU
var reset = function() {
regSR.D = false;
regSR.I = true;
regSR.B = true;
stopped = false;
waiting = false;
regPC = memCtrl.getAddr(VECTOR_RST);
cycle += 7;
};
// Interrupt request (via the IRQ pin)
this.irq = function() {
// Only do an IRQ interrupt if I flag is clear and the processor isn't stopped
// Also, NMI interrupts have priority over IRQ
if (! stopped) {
waiting = false; // Allow execution to continue past WAI, even if the IRQ isn't taken
if (!regSR.I && !this.nmi_pin) {
pushStackAddr(regPC); // push PC
regSR.B = false;
pushStack(regSR.get()); // push SR with B flag clear
regSR.I = true; // set interrupt disable flag
regSR.D = false; // clear D flag before jumping (new for 65C02)
regPC = memCtrl.getAddr(VECTOR_IRQ);
PCinc = 0;
cycle += 7;
}
}
};
// Non-maskable interrupt request (via the NMI pin)
var nmi = function() {
// Alway do an IRQ interrupt unless the processor is stopeed
if (!stopped) {
this.nmi_pin = false; // NMI is edge sensitive interrupt
waiting = false;
pushStackAddr(regPC); // push PC
regSR.B = false;
pushStack(regSR.get()); // push SR with B flag clear
regSR.I = true; // set interrupt disable flag
regSR.D = false; // clear D flag before jumping (new for 65C02)
regPC = memCtrl.getAddr(VECTOR_NMI);
PCinc = 0;
cycle += 7;
}
};
return {
irq_pin: this.irq_pin,
nmi_pin: this.nmi_pin,
regA: function() {return regA;},
regX: function() {return regX;},
regY: function() {return regY;},
regSP: function() {return regSP;},
regPC: function() {return regPC;},
regSR: function() {return regSR;},
setA: function(value) {regA = value & 0xFF; },
setX: function(value) {regX = value & 0xFF; },
setY: function(value) {regY = value & 0xFF; },
setSP: function(value) {regSP = value & 0xFF; },
setPC: function(value) {regPC = value & 0xFFFF; },
setSR: function(value) {regSR.set(value); },
cycle: function() {return cycle;},
run: run,
reset: reset,
irq: irq,
nmi: nmi
};
}

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var STR_PAD_LEFT = 1;
var STR_PAD_RIGHT = 2;
var STR_PAD_BOTH = 3;
function pad(str, len, pad, dir) {
if (typeof(len) == "undefined") { var len = 0; }
if (typeof(pad) == "undefined") { var pad = ' '; }
if (typeof(dir) == "undefined") { var dir = STR_PAD_RIGHT; }
if (len + 1 >= str.length) {
switch (dir){
case STR_PAD_LEFT:
str = Array(len + 1 - str.length).join(pad) + str;
break;
case STR_PAD_BOTH:
var right = Math.ceil((padlen = len - str.length) / 2);
var left = padlen - right;
str = Array(left+1).join(pad) + str + Array(right+1).join(pad);
break;
default:
str = str + Array(len + 1 - str.length).join(pad);
break;
} // switch
}
return str;
}
function Disassembler(memCtrl) {
this.memCtrl = memCtrl;
this.regPC = 0x0000; // program counter
this.disassemble = function(startloc, nbytes) {
var bytecount = 0;
this.regPC = startloc;
do {
dissambly = this.opToStr();
bytecount += dissambly.numBytes;
console.log(dissambly.text);
} while (bytecount < nbytes);
};
this.opToStr = function() {
var numbytes = 0;
var startpos = 0;
var mem_dump;
var opcode = this.memCtrl.getData(this.regPC);
var am_string = this.optable[opcode][1];
// Get the hex address of the opcode and the opcode hex code
mem_dump = "$" + this.regPC.toString(16) + ": " + opcode.toString(16);
this.regPC = (this.regPC + 1) & 0xFFFF;
numbytes++;
var pos = am_string.indexOf("ADDR", startpos);
if (pos != -1) {
mem_dump += " " + this.memCtrl.getData(this.regPC).toString(16);
mem_dump += " " + this.memCtrl.getData((this.regPC + 1) & 0xFFFF).toString(16);
am_string = am_string.replace("ADDR", this.memCtrl.getAddr(this.regPC).toString(16));
startpos += 4;
this.regPC = (this.regPC + 2) & 0xFFFF;
numbytes += 2;
}
pos = am_string.indexOf("BIT", startpos);
if (pos != -1) {
var bitStr = (((opcode & 0xF0) >> 4) % 8).toString();
am_string = am_string.replace("BIT", bitStr);
startpos += 1;
}
pos = am_string.indexOf("BYTE", startpos);
if (pos != -1) {
mem_dump += " " + this.memCtrl.getData(this.regPC).toString(16);
am_string = am_string.replace("BYTE", this.memCtrl.getData(this.regPC).toString(16));
startpos += 2;
this.regPC = (this.regPC + 1) & 0xFFFF;
numbytes++;
}
pos = am_string.indexOf("BYTE", startpos);
if (pos != -1) {
mem_dump += " " + this.memCtrl.getData(this.regPC).toString(16);
am_string = am_string.replace("BYTE", this.memCtrl.getData(this.regPC).toString(16));
this.regPC += (this.regPC + 1) & 0xFFFF;
numbytes++;
}
mem_dump = pad(mem_dump, 20, ' ', STR_PAD_RIGHT).toUpperCase();
var finalStr = mem_dump + this.optable[opcode][0] + " " + am_string.toUpperCase();
return {numBytes: numbytes, text: finalStr};
};
this.optable = new Array(256);
this.optable[0x00] = ["BRK", ""];
this.optable[0x01] = ["ORA", "($BYTE,X)"];
this.optable[0x02] = ["NOP", ""];
this.optable[0x03] = ["NOP", ""];
this.optable[0x04] = ["TSB", "$BYTE"];
this.optable[0x05] = ["ORA", "$BYTE"];
this.optable[0x06] = ["ASL", "$BYTE"];
this.optable[0x07] = ["RMB", "BIT,$BYTE"];
this.optable[0x08] = ["PHP", ""];
this.optable[0x09] = ["ORA", "#BYTE"];
this.optable[0x0A] = ["ASL", "A"];
this.optable[0x0B] = ["NOP", ""];
this.optable[0x0C] = ["TSB", "$ADDR"];
this.optable[0x0D] = ["ORA", "$ADDR"];
this.optable[0x0E] = ["ASL", "$ADDR"];
this.optable[0x0F] = ["BBR", "BIT,$BYTE,BYTE"];
this.optable[0x10] = ["BPL", "BYTE"];
this.optable[0x11] = ["ORA", "($BYTE),Y"];
this.optable[0x12] = ["ORA", "($BYTE)"];
this.optable[0x13] = ["NOP", ""];
this.optable[0x14] = ["TRB", "$BYTE"];
this.optable[0x15] = ["ORA", "$BYTE,X"];
this.optable[0x16] = ["ASL", "$BYTE,X"];
this.optable[0x17] = ["RMB", "BIT,$BYTE"];
this.optable[0x18] = ["CLC", ""];
this.optable[0x19] = ["ORA", "$ADDR,Y"];
this.optable[0x1A] = ["INA", "A"];
this.optable[0x1B] = ["NOP", ""];
this.optable[0x1C] = ["TRB", "$ADDR"];
this.optable[0x1D] = ["ORA", "$ADDR,X"];
this.optable[0x1E] = ["ASL", "$ADDR,X"];
this.optable[0x1F] = ["BBR", "BIT,$BYTE,BYTE"];
this.optable[0x20] = ["JSR", "$ADDR"];
this.optable[0x21] = ["AND", "($BYTE,X)"];
this.optable[0x22] = ["NOP", ""];
this.optable[0x23] = ["NOP", ""];
this.optable[0x24] = ["BIT", "$BYTE"];
this.optable[0x25] = ["AND", "$BYTE"];
this.optable[0x26] = ["ROL", "$BYTE"];
this.optable[0x27] = ["RMB", "BIT,$BYTE"];
this.optable[0x28] = ["PLP", ""];
this.optable[0x29] = ["AND", "#BYTE"];
this.optable[0x2A] = ["ROL", "A"];
this.optable[0x2B] = ["NOP", ""];
this.optable[0x2C] = ["BIT", "$ADDR"];
this.optable[0x2D] = ["AND", "$ADDR"];
this.optable[0x2E] = ["ROL", "$ADDR"];
this.optable[0x2F] = ["BBR", "BIT,$BYTE,BYTE"];
this.optable[0x30] = ["BMI", "BYTE"];
this.optable[0x31] = ["AND", "($BYTE),Y"];
this.optable[0x32] = ["AND", "($BYTE)"];
this.optable[0x33] = ["NOP", ""];
this.optable[0x34] = ["BIT", "$BYTE,X"];
this.optable[0x35] = ["AND", "$BYTE,X"];
this.optable[0x36] = ["ROL", "$BYTE,X"];
this.optable[0x37] = ["RMB", "BIT,$BYTE"];
this.optable[0x38] = ["SEC", ""];
this.optable[0x39] = ["AND", "$ADDR,Y"];
this.optable[0x3A] = ["DEA", "A"];
this.optable[0x3B] = ["NOP", ""];
this.optable[0x3C] = ["BIT", "$ADDR,X"];
this.optable[0x3D] = ["AND", "$ADDR,X"];
this.optable[0x3E] = ["ROL", "$ADDR,X"];
this.optable[0x3F] = ["BBR", "BIT,$BYTE,BYTE"];
this.optable[0x40] = ["RTI", ""];
this.optable[0x41] = ["EOR", "($BYTE,X)"];
this.optable[0x42] = ["NOP", ""];
this.optable[0x43] = ["NOP", ""];
this.optable[0x44] = ["NOP", ""];
this.optable[0x45] = ["EOR", "$BYTE"];
this.optable[0x46] = ["LSR", "$BYTE"];
this.optable[0x47] = ["RMB", "BIT,$BYTE"];
this.optable[0x48] = ["PHA", ""];
this.optable[0x49] = ["EOR", "#BYTE"];
this.optable[0x4A] = ["LSR", "A"];
this.optable[0x4B] = ["NOP", ""];
this.optable[0x4C] = ["JMP", "$ADDR"];
this.optable[0x4D] = ["EOR", "$ADDR"];
this.optable[0x4E] = ["LSR", "$ADDR"];
this.optable[0x4F] = ["BBR", "BIT,$BYTE,BYTE"];
this.optable[0x50] = ["BVC", "BYTE"];
this.optable[0x51] = ["EOR", "($BYTE),Y"];
this.optable[0x52] = ["EOR", "($BYTE)"];
this.optable[0x53] = ["NOP", ""];
this.optable[0x54] = ["NOP", ""];
this.optable[0x55] = ["EOR", "$BYTE,X"];
this.optable[0x56] = ["LSR", "$BYTE,X"];
this.optable[0x57] = ["RMB", "BIT,$BYTE"];
this.optable[0x58] = ["CLI", ""];
this.optable[0x59] = ["EOR", "$ADDR,Y"];
this.optable[0x5A] = ["PHY", ""];
this.optable[0x5B] = ["NOP", ""];
this.optable[0x5C] = ["NOP", ""];
this.optable[0x5D] = ["EOR", "$ADDR,X"];
this.optable[0x5E] = ["LSR", "$ADDR,X"];
this.optable[0x5F] = ["BBR", "BIT,$BYTE,BYTE"];
this.optable[0x60] = ["RTS", ""];
this.optable[0x61] = ["ADC", "($BYTE,X)"];
this.optable[0x62] = ["NOP", ""];
this.optable[0x63] = ["NOP", ""];
this.optable[0x64] = ["STZ", "$BYTE"];
this.optable[0x65] = ["ADC", "$BYTE"];
this.optable[0x66] = ["ROR", "$BYTE"];
this.optable[0x67] = ["RMB", "BIT,$BYTE"];
this.optable[0x68] = ["PLA", ""];
this.optable[0x69] = ["ADC", "#BYTE"];
this.optable[0x6A] = ["ROR", "A"];
this.optable[0x6B] = ["NOP", ""];
this.optable[0x6C] = ["JMP", "($ADDR)"];
this.optable[0x6D] = ["ADC", "$ADDR"];
this.optable[0x6E] = ["ROR", "$ADDR"];
this.optable[0x6F] = ["BBR", "BIT,$BYTE,BYTE"];
this.optable[0x70] = ["BVS", "BYTE"];
this.optable[0x71] = ["ADC", "($BYTE),Y"];
this.optable[0x72] = ["ADC", "($BYTE)"];
this.optable[0x73] = ["NOP", ""];
this.optable[0x74] = ["STZ", "$BYTE,X"];
this.optable[0x75] = ["ADC", "$BYTE,X"];
this.optable[0x76] = ["ROR", "$BYTE,X"];
this.optable[0x77] = ["RMB", "BIT,$BYTE"];
this.optable[0x78] = ["SEI", ""];
this.optable[0x79] = ["ADC", "$ADDR,Y"];
this.optable[0x7A] = ["PLY", ""];
this.optable[0x7B] = ["NOP", ""];
this.optable[0x7C] = ["JMP", "($ADDR,X)"];
this.optable[0x7D] = ["ADC", "$ADDR,X"];
this.optable[0x7E] = ["ROR", "$ADDR,X"];
this.optable[0x7F] = ["BBR", "BIT,$BYTE,BYTE"];
this.optable[0x80] = ["BRA", "BYTE"];
this.optable[0x81] = ["STA", "($BYTE,X)"];
this.optable[0x82] = ["NOP", ""];
this.optable[0x83] = ["NOP", ""];
this.optable[0x84] = ["STY", "$BYTE"];
this.optable[0x85] = ["STA", "$BYTE"];
this.optable[0x86] = ["STX", "$BYTE"];
this.optable[0x87] = ["SMB", "BIT,$BYTE"];
this.optable[0x88] = ["DEY", ""];
this.optable[0x89] = ["BIT", "#BYTE"];
this.optable[0x8A] = ["TXA", ""];
this.optable[0x8B] = ["NOP", ""];
this.optable[0x8C] = ["STY", "$ADDR"];
this.optable[0x8D] = ["STA", "$ADDR"];
this.optable[0x8E] = ["STX", "$ADDR"];
this.optable[0x8F] = ["BBS", "BIT,$BYTE,BYTE"];
this.optable[0x90] = ["BCC", "BYTE"];
this.optable[0x91] = ["STA", "($BYTE),Y"];
this.optable[0x92] = ["STA", "($BYTE)"];
this.optable[0x93] = ["NOP", ""];
this.optable[0x94] = ["STY", "$BYTE,X"];
this.optable[0x95] = ["STA", "$BYTE,X"];
this.optable[0x96] = ["STX", "$BYTE,Y"];
this.optable[0x97] = ["SMB", "BIT,$BYTE"];
this.optable[0x98] = ["TYA", ""];
this.optable[0x99] = ["STA", "$ADDR,Y"];
this.optable[0x9A] = ["TXS", ""];
this.optable[0x9B] = ["NOP", ""];
this.optable[0x9C] = ["STZ", "$ADDR"];
this.optable[0x9D] = ["STA", "$ADDR,X"];
this.optable[0x9E] = ["STZ", "$ADDR,X"];
this.optable[0x9F] = ["BBS", "BIT,$BYTE,BYTE"];
this.optable[0xA0] = ["LDY", "#BYTE"];
this.optable[0xA1] = ["LDA", "($BYTE,X)"];
this.optable[0xA2] = ["LDX", "#BYTE"];
this.optable[0xA3] = ["NOP", ""];
this.optable[0xA4] = ["LDY", "$BYTE"];
this.optable[0xA5] = ["LDA", "$BYTE"];
this.optable[0xA6] = ["LDX", "$BYTE"];
this.optable[0xA7] = ["SMB", "BIT,$BYTE"];
this.optable[0xA8] = ["TAY", ""];
this.optable[0xA9] = ["LDA", "#BYTE"];
this.optable[0xAA] = ["TAX", ""];
this.optable[0xAB] = ["NOP", ""];
this.optable[0xAC] = ["LDY", "$ADDR"];
this.optable[0xAD] = ["LDA", "$ADDR"];
this.optable[0xAE] = ["LDX", "$ADDR"];
this.optable[0xAF] = ["BBS", "BIT,$BYTE,BYTE"];
this.optable[0xB0] = ["BCS", "BYTE"];
this.optable[0xB1] = ["LDA", "($BYTE),Y"];
this.optable[0xB2] = ["LDA", "($BYTE)"];
this.optable[0xB3] = ["NOP", ""];
this.optable[0xB4] = ["LDY", "$BYTE,X"];
this.optable[0xB5] = ["LDA", "$BYTE,X"];
this.optable[0xB6] = ["LDX", "$BYTE,Y"];
this.optable[0xB7] = ["SMB", "BIT,$BYTE"];
this.optable[0xB8] = ["CLV", ""];
this.optable[0xB9] = ["LDA", "$ADDR,Y"];
this.optable[0xBA] = ["TSX", ""];
this.optable[0xBB] = ["NOP", ""];
this.optable[0xBC] = ["LDY", "$ADDR,X"];
this.optable[0xBD] = ["LDA", "$ADDR,X"];
this.optable[0xBE] = ["LDX", "$ADDR,Y"];
this.optable[0xBF] = ["BBS", "BIT,$BYTE,BYTE"];
this.optable[0xC0] = ["CPY", "#BYTE"];
this.optable[0xC1] = ["CMP", "($BYTE,X)"];
this.optable[0xC2] = ["NOP", ""];
this.optable[0xC3] = ["NOP", ""];
this.optable[0xC4] = ["CPY", "$BYTE"];
this.optable[0xC5] = ["CMP", "$BYTE"];
this.optable[0xC6] = ["DEC", "$BYTE"];
this.optable[0xC7] = ["SMB", "BIT,$BYTE"];
this.optable[0xC8] = ["INY", ""];
this.optable[0xC9] = ["CMP", "#BYTE"];
this.optable[0xCA] = ["DEX", ""];
this.optable[0xCB] = ["WAI", ""];
this.optable[0xCC] = ["CPY", "$ADDR"];
this.optable[0xCD] = ["CMP", "$ADDR"];
this.optable[0xCE] = ["DEC", "$ADDR"];
this.optable[0xCF] = ["BBS", "BIT,$BYTE,BYTE"];
this.optable[0xD0] = ["BNE", "BYTE"];
this.optable[0xD1] = ["CMP", "($BYTE),Y"];
this.optable[0xD2] = ["CMP", "($BYTE)"];
this.optable[0xD3] = ["NOP", ""];
this.optable[0xD4] = ["NOP", ""];
this.optable[0xD5] = ["CMP", "$BYTE,X"];
this.optable[0xD6] = ["DEC", "$BYTE,X"];
this.optable[0xD7] = ["SMB", "BIT,$BYTE"];
this.optable[0xD8] = ["CLD", ""];
this.optable[0xD9] = ["CMP", "$ADDR,Y"];
this.optable[0xDA] = ["PHX", ""];
this.optable[0xDB] = ["STP", ""];
this.optable[0xDC] = ["NOP", ""];
this.optable[0xDD] = ["CMP", "$ADDR,X"];
this.optable[0xDE] = ["DEC", "$ADDR,X"];
this.optable[0xDF] = ["BBS", "BIT,$BYTE,BYTE"];
this.optable[0xE0] = ["CPX", "#BYTE"];
this.optable[0xE1] = ["SBC", "($BYTE,X)"];
this.optable[0xE2] = ["NOP", ""];
this.optable[0xE3] = ["NOP", ""];
this.optable[0xE4] = ["CPX", "$BYTE"];
this.optable[0xE5] = ["SBC", "$BYTE"];
this.optable[0xE6] = ["INC", "$BYTE"];
this.optable[0xE7] = ["SMB", "BIT,$BYTE"];
this.optable[0xE8] = ["INX", ""];
this.optable[0xE9] = ["SBC", "#BYTE"];
this.optable[0xEA] = ["NOP", ""];
this.optable[0xEB] = ["NOP", ""];
this.optable[0xEC] = ["CPX", "$ADDR"];
this.optable[0xED] = ["SBC", "$ADDR"];
this.optable[0xEE] = ["INC", "$ADDR"];
this.optable[0xEF] = ["BBS", "BIT,$BYTE,BYTE"];
this.optable[0xF0] = ["BEQ", "BYTE"];
this.optable[0xF1] = ["SBC", "($BYTE),Y"];
this.optable[0xF2] = ["SBC", "($BYTE)"];
this.optable[0xF3] = ["NOP", ""];
this.optable[0xF4] = ["NOP", ""];
this.optable[0xF5] = ["SBC", "$BYTE,X"];
this.optable[0xF6] = ["INC", "$BYTE,X"];
this.optable[0xF7] = ["SMB", "BIT,$BYTE"];
this.optable[0xF8] = ["SED", ""];
this.optable[0xF9] = ["SBC", "$ADDR,Y"];
this.optable[0xFA] = ["PLX", ""];
this.optable[0xFB] = ["NOP", ""];
this.optable[0xFC] = ["NOP", ""];
this.optable[0xFD] = ["SBC", "$ADDR,X"];
this.optable[0xFE] = ["INC", "$ADDR,X"];
this.optable[0xFF] = ["BBS", "BIT,$BYTE,BYTE"];
}

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<!DOCTYPE html>
<html>
<head>
<title>JavaScript 65C02 CPU Emulator</title>
<script type="text/javascript" src="//cdnjs.cloudflare.com/ajax/libs/jquery/2.1.3/jquery.min.js"></script>
</head>
<body>
<div align="center" id="screen"></div>
<h3>Check the console for the cool output!</h3>
<div id="status">LOADING</div>
<h4>Output:</h4>
<div id="output"></div>
<script src="resources.js"></script>
<script src="cpu.js"></script>
<script src="monitor.js"></script>
<script src="memory.js"></script>
<script src="disassembler.js"></script>
<script src="main.js"></script>
</body>
</html>

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// A cross-browser requestAnimationFrame
// See https://hacks.mozilla.org/2011/08/animating-with-javascript-from-setinterval-to-requestanimationframe/
var requestAnimFrame = (function(){
return window.requestAnimationFrame ||
window.webkitRequestAnimationFrame ||
window.mozRequestAnimationFrame ||
window.oRequestAnimationFrame ||
window.msRequestAnimationFrame ||
function(callback){
window.setTimeout(callback, 1000 / 60);
};
})();
var mem64k = new DebugMemController();
var cpu = Cpu(mem64k);
var dis = new Disassembler(mem64k);
var mon = new Monitor(cpu);
var intervalId; // id for interval timer
var print_flag = true;
var old_irq_pin;
var old_nmi_pin;
var statusElem;
// The main game loop
var lastTime;
function main() {
console.log("Inside main");
var now = Date.now();
var dt = (now - lastTime) / 1000.0;
runCPU(dt);
render();
lastTime = now;
requestAnimFrame(main);
}
function init() {
console.log("Inside init");
// Create the canvas
var canvas = document.createElement("canvas");
var ctx = canvas.getContext("2d");
canvas.width = 512;
canvas.height = 480;
document.getElementById("screen").appendChild(canvas);
statusElem = document.getElementById("status");
mem64k.loadData(0x0000, resources.get('test6502'));
cpu.reset();
old_irq_pin = (mem64k.getData(0xBFFC) & 0x01) > 0;
old_nmi_pin = ((mem64k.getData(0xBFFC) & 0x02) >> 1) > 0;
cpu.setPC(0x0400);
console.log("Press keys to operate CPU:");
console.log("0) reset");
console.log("1) NMI");
console.log("2) IRQ");
console.log("3) end simulation");
print_flag = false;
statusElem.innerHTML = "Running";
lastTime = Date.now;
main();
}
function runCPU(dt) {
var numCycles = dt*1022727;
if (print_flag) {
console.log(mon.getStatusStr());
dis.disassemble(cpu.regPC());
}
cpu_start = Date.now();
cpu.run(numCycles);
cpu_dt = (Date.now() - cpu_start) / 1000.0;
console.log('CPU time = ' + cpu_dt);
var irq_pin = (mem64k.getData(0xBFFC) & 0x01) > 0;
var nmi_pin = ((mem64k.getData(0xBFFC) & 0x02) >> 1) > 0;
if (irq_pin != old_irq_pin) {
console.log("Changed IRQ pin: " + old_irq_pin + " --> " + irq_pin);
old_irq_pin = irq_pin;
cpu.irq_pin = irq_pin;
}
if (nmi_pin != old_nmi_pin) {
console.log("Changed NMI pin: " + old_nmi_pin + " --> " + nmi_pin);
old_nmi_pin = nmi_pin;
cpu.nmi_pin = nmi_pin;
}
}
function render() {
// Nothing yet
}
document.onkeypress = function (e) {
e = e || window.event;
if (e.keyCode === 51) {
clearInterval(intervalId);
console.log("STOPPED");
statusElem.innerHTML = "STOPPED";
}
else if (e.keyCode === 48) { cpu.reset(); statusElem.innerHTML = "Running (" + intervalId + "): ";}
else if(e.keyCode === 49) { cpu.nmi(); statusElem.innerHTML += "1 ";}
else if(e.keyCode === 50) { cpu.irq(); statusElem.innerHTML += "2 ";}
else if(e.keyCode >= 0 && e.keyCode <= 255) {
mem64k.setData(mem64k.in_port, e.keyCode);
}
};
$(document).ready(function() {
console.log("Document ready");
$.when(
resources.loadBinary('/tests/6502_functional_test.bin', 'test6502')
).then(function() {
init();
}, function() {
console.log("Resource not available");
}) ;
});

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function DebugMemController() {
this.in_port = 0xBFF0;
this.out_port = 0xBFF0;
// Create the memory bank and fill it with 0's
this.bank0 = new Array(65536);
var i = 0;
while (i < 65536) { this.bank0[i] = 0x00; i++; }
}
// Return an 8-bit chuck of data at a given address
DebugMemController.prototype.getData = function(addr) {
return this.bank0[addr];
};
// Return a 16-bit chuck of data at a given address
DebugMemController.prototype.getAddr = function(addr) {
return this.bank0[addr] | this.bank0[(addr+1) & 0xFFFF] << 8;
};
// Assign an 8-bit value to a given address
DebugMemController.prototype.setData = function(addr, value) {
this.bank0[addr] = value;
if (addr === this.out_port) {
if (value !== 10 && value !== 13) {
document.getElementById("output").innerHTML += String.fromCharCode(value);
} else {
document.getElementById("output").innerHTML += '<br />';
}
}
};
// Load a block of data in memory starting at addr
DebugMemController.prototype.loadData = function(addr, data) {
var end_data = data.length;
if (end_data > (65536 - addr)) {
end_data = 65536 - addr;
}
// Copy the data into bank 0
var isrc = 0;
while(isrc < end_data) { this.bank0[addr+isrc] = data[isrc]; isrc++; }
};
// Return an array specified number of bytes starting at addr
DebugMemController.prototype.dumpData = function(addr, nbytes) {
var end_addr = addr + nbytes;
if (end_addr > 65536) {
// truncate the data
end_addr = 65536;
}
return this.bank0.slice(addr, end_addr);
};

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function Monitor(cpu) {
this.cpu = cpu;
this.getStatusStr = function() {
var status;
status = "PC=" + this.cpu.regPC().toString(16);
status += " A=" + this.cpu.regA().toString(16);
status += " X=" + this.cpu.regX().toString(16);
status += " Y=" + this.cpu.regY().toString(16);
status += " SP=01" + this.cpu.regSP().toString(16);
status += " SR=";
status = status.toUpperCase();
if (this.cpu.regSR().N) { status += "N"; } else { status += "n"; }
if (this.cpu.regSR().V) { status += "V1"; } else { status += "v1"; }
if (this.cpu.regSR().B) { status += "B"; } else { status += "b"; }
if (this.cpu.regSR().D) { status += "D"; } else { status += "d"; }
if (this.cpu.regSR().I) { status += "I"; } else { status += "i"; }
if (this.cpu.regSR().Z) { status += "Z"; } else { status += "z"; }
if (this.cpu.regSR().C) { status += "C"; } else { status += "c"; }
status += " (" + this.cpu.regSR().get().toString(16).toUpperCase() + ")";
status += ", cycle = " + this.cpu.cycle().toString();
return status;
};
}

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// use this transport for "binary" data type
$.ajaxTransport("+binary", function(options, originalOptions, jqXHR){
// check for conditions and support for blob / arraybuffer response type
if (window.FormData && ((options.dataType && (options.dataType == 'binary')) || (options.data && ((window.ArrayBuffer && options.data instanceof ArrayBuffer) || (window.Blob && options.data instanceof Blob)))))
{
return {
// create new XMLHttpRequest
send: function(_, callback){
// setup all variables
var xhr = new XMLHttpRequest(),
url = options.url,
type = options.type,
// blob or arraybuffer. Default is blob
dataType = options.responseType || "blob",
data = options.data || null;
xhr.addEventListener('load', function(){
var data = {};
data[options.dataType] = xhr.response;
// make callback and send data
callback(xhr.status, xhr.statusText, data, xhr.getAllResponseHeaders());
});
xhr.open(type, url, true);
xhr.responseType = dataType;
xhr.send(data);
},
abort: function(){
jqXHR.abort();
}
};
}
});
(function() {
var resourceCache = [];
function loadBinary(url, name) {
return $.ajax({
url: url,
type: "GET",
dataType: 'binary',
responseType:'arraybuffer',
processData: false,
success: function(result){
// create unsigned Int array and convert this array into blob
var arrayBufferView = new Uint8Array(result );
console.log("Resource loaded: " + url);
resourceCache[name] = arrayBufferView;
return arrayBufferView;
}
});
}
function get(name) {
return resourceCache[name];
}
window.resources = {
loadBinary: loadBinary,
get: get
};
})();