Simulator is just about ready for real-world testing now. Added a simulated
MOS6551 ACIA at address $C000 which does buffered input and output via the console. Updated the README with a bit more documentation, and bumped the version number to 0.1 because I'm impatient.
This commit is contained in:
Seth J. Morabito committed
1 parent
596d05e398
commit
00ab8cd9ff
10 files changed
+749
-124
No files matched your search
@@ -50,7 +50,6 @@ public class Cpu implements InstructionTable {
|
||||
private int irAddressMode; // Bits 3-5 of IR: [ | | |X|X|X| | ]
|
||||
private int irOpMode; // Bits 6-7 of IR: [ | | | | | |X|X]
|
||||
private int effectiveAddress;
|
||||
private int effectiveData;
|
||||
|
||||
/* Internal scratch space */
|
||||
private int lo = 0, hi = 0; // Used in address calculation
|
||||
@@ -149,24 +148,20 @@ public class Cpu implements InstructionTable {
|
||||
// Get the data from the effective address (if any)
|
||||
|
||||
effectiveAddress = 0;
|
||||
effectiveData = 0;
|
||||
|
||||
switch(irOpMode) {
|
||||
case 0:
|
||||
case 2:
|
||||
switch(irAddressMode) {
|
||||
case 0: // #Immediate
|
||||
effectiveData = args[0];
|
||||
break;
|
||||
case 1: // Zero Page
|
||||
effectiveAddress = args[0];
|
||||
effectiveData = bus.read(effectiveAddress);
|
||||
break;
|
||||
case 2: // Accumulator - ignored
|
||||
break;
|
||||
case 3: // Absolute
|
||||
effectiveAddress = address(args[0], args[1]);
|
||||
effectiveData = bus.read(effectiveAddress);
|
||||
break;
|
||||
case 5: // Zero Page,X / Zero Page,Y
|
||||
if (ir == 0x96 || ir == 0xb6) {
|
||||
@@ -174,7 +169,6 @@ public class Cpu implements InstructionTable {
|
||||
} else {
|
||||
effectiveAddress = zpxAddress(args[0]);
|
||||
}
|
||||
effectiveData = bus.read(effectiveAddress);
|
||||
break;
|
||||
case 7: // Absolute,X / Absolute,Y
|
||||
if (ir == 0xbe) {
|
||||
@@ -182,7 +176,6 @@ public class Cpu implements InstructionTable {
|
||||
} else {
|
||||
effectiveAddress = xAddress(args[0], args[1]);
|
||||
}
|
||||
effectiveData = bus.read(effectiveAddress);
|
||||
break;
|
||||
}
|
||||
break;
|
||||
@@ -191,37 +184,29 @@ public class Cpu implements InstructionTable {
|
||||
case 0: // (Zero Page,X)
|
||||
tmp = args[0] + getXRegister();
|
||||
effectiveAddress = address(bus.read(tmp), bus.read(tmp + 1));
|
||||
effectiveData = bus.read(effectiveAddress);
|
||||
break;
|
||||
case 1: // Zero Page
|
||||
effectiveAddress = args[0];
|
||||
effectiveData = bus.read(effectiveAddress);
|
||||
break;
|
||||
case 2: // #Immediate
|
||||
effectiveAddress = -1;
|
||||
effectiveData = args[0];
|
||||
break;
|
||||
case 3: // Absolute
|
||||
effectiveAddress = address(args[0], args[1]);
|
||||
effectiveData = bus.read(effectiveAddress);
|
||||
break;
|
||||
case 4: // (Zero Page),Y
|
||||
tmp = address(bus.read(args[0]),
|
||||
bus.read((args[0]+1)&0xff));
|
||||
effectiveAddress = (tmp + getYRegister())&0xffff;
|
||||
effectiveData = bus.read(effectiveAddress);
|
||||
break;
|
||||
case 5: // Zero Page,X
|
||||
effectiveAddress = zpxAddress(args[0]);
|
||||
effectiveData = bus.read(effectiveAddress);
|
||||
break;
|
||||
case 6: // Absolute, Y
|
||||
effectiveAddress = yAddress(args[0], args[1]);
|
||||
effectiveData = bus.read(effectiveAddress);
|
||||
break;
|
||||
case 7: // Absolute, X
|
||||
effectiveAddress = xAddress(args[0], args[1]);
|
||||
effectiveData = bus.read(effectiveAddress);
|
||||
break;
|
||||
}
|
||||
break;
|
||||
@@ -402,15 +387,18 @@ public class Cpu implements InstructionTable {
|
||||
|
||||
|
||||
/** ORA - Logical Inclusive Or ******************************************/
|
||||
case 0x09: // #Immediate
|
||||
a |= args[0];
|
||||
setArithmeticFlags(a);
|
||||
break;
|
||||
case 0x01: // (Zero Page,X)
|
||||
case 0x05: // Zero Page
|
||||
case 0x09: // #Immediate
|
||||
case 0x0d: // Absolute
|
||||
case 0x11: // (Zero Page),Y
|
||||
case 0x15: // Zero Page,X
|
||||
case 0x19: // Absolute,Y
|
||||
case 0x1d: // Absolute,X
|
||||
a |= effectiveData;
|
||||
a |= bus.read(effectiveAddress);
|
||||
setArithmeticFlags(a);
|
||||
break;
|
||||
|
||||
@@ -424,7 +412,7 @@ public class Cpu implements InstructionTable {
|
||||
case 0x0e: // Absolute
|
||||
case 0x16: // Zero Page,X
|
||||
case 0x1e: // Absolute,X
|
||||
tmp = asl(effectiveData);
|
||||
tmp = asl(bus.read(effectiveAddress));
|
||||
bus.write(effectiveAddress, tmp);
|
||||
setArithmeticFlags(tmp);
|
||||
break;
|
||||
@@ -433,7 +421,7 @@ public class Cpu implements InstructionTable {
|
||||
/** BIT - Bit Test ******************************************************/
|
||||
case 0x24: // Zero Page
|
||||
case 0x2c: // Absolute
|
||||
tmp = a & effectiveData;
|
||||
tmp = a & bus.read(effectiveAddress);
|
||||
setZeroFlag(tmp == 0);
|
||||
setNegativeFlag((tmp & 0x80) != 0);
|
||||
setOverflowFlag((tmp & 0x40) != 0);
|
||||
@@ -441,15 +429,18 @@ public class Cpu implements InstructionTable {
|
||||
|
||||
|
||||
/** AND - Logical AND ***************************************************/
|
||||
case 0x29: // #Immediate
|
||||
a &= args[0];
|
||||
setArithmeticFlags(a);
|
||||
break;
|
||||
case 0x21: // (Zero Page,X)
|
||||
case 0x25: // Zero Page
|
||||
case 0x29: // #Immediate
|
||||
case 0x2d: // Absolute
|
||||
case 0x31: // (Zero Page),Y
|
||||
case 0x35: // Zero Page,X
|
||||
case 0x39: // Absolute,Y
|
||||
case 0x3d: // Absolute,X
|
||||
a &= effectiveData;
|
||||
a &= bus.read(effectiveAddress);
|
||||
setArithmeticFlags(a);
|
||||
break;
|
||||
|
||||
@@ -463,22 +454,25 @@ public class Cpu implements InstructionTable {
|
||||
case 0x2e: // Absolute
|
||||
case 0x36: // Zero Page,X
|
||||
case 0x3e: // Absolute,X
|
||||
tmp = rol(effectiveData);
|
||||
tmp = rol(bus.read(effectiveAddress));
|
||||
bus.write(effectiveAddress, tmp);
|
||||
setArithmeticFlags(tmp);
|
||||
break;
|
||||
|
||||
|
||||
/** EOR - Exclusive OR **************************************************/
|
||||
case 0x49: // #Immediate
|
||||
a ^= args[0];
|
||||
setArithmeticFlags(a);
|
||||
break;
|
||||
case 0x41: // (Zero Page,X)
|
||||
case 0x45: // Zero Page
|
||||
case 0x49: // Immediate
|
||||
case 0x4d: // Absolute
|
||||
case 0x51: // (Zero Page,Y)
|
||||
case 0x55: // Zero Page,X
|
||||
case 0x59: // Absolute,Y
|
||||
case 0x5d: // Absolute,X
|
||||
a ^= effectiveData;
|
||||
a ^= bus.read(effectiveAddress);
|
||||
setArithmeticFlags(a);
|
||||
break;
|
||||
|
||||
@@ -492,25 +486,31 @@ public class Cpu implements InstructionTable {
|
||||
case 0x4e: // Absolute
|
||||
case 0x56: // Zero Page,X
|
||||
case 0x5e: // Absolute,X
|
||||
tmp = lsr(effectiveData);
|
||||
tmp = lsr(bus.read(effectiveAddress));
|
||||
bus.write(effectiveAddress, tmp);
|
||||
setArithmeticFlags(tmp);
|
||||
break;
|
||||
|
||||
|
||||
/** ADC - Add with Carry ************************************************/
|
||||
case 0x69: // #Immediate
|
||||
if (decimalModeFlag) {
|
||||
a = adcDecimal(a, args[0]);
|
||||
} else {
|
||||
a = adc(a, args[0]);
|
||||
}
|
||||
break;
|
||||
case 0x61: // (Zero Page,X)
|
||||
case 0x65: // Zero Page
|
||||
case 0x69: // Immediate
|
||||
case 0x6d: // Absolute
|
||||
case 0x71: // (Zero Page),Y
|
||||
case 0x75: // Zero Page,X
|
||||
case 0x79: // Absolute,Y
|
||||
case 0x7d: // Absolute,X
|
||||
if (decimalModeFlag) {
|
||||
a = adcDecimal(a, effectiveData);
|
||||
a = adcDecimal(a, bus.read(effectiveAddress));
|
||||
} else {
|
||||
a = adc(a, effectiveData);
|
||||
a = adc(a, bus.read(effectiveAddress));
|
||||
}
|
||||
break;
|
||||
|
||||
@@ -524,7 +524,7 @@ public class Cpu implements InstructionTable {
|
||||
case 0x6e: // Absolute
|
||||
case 0x76: // Zero Page,X
|
||||
case 0x7e: // Absolute,X
|
||||
tmp = ror(effectiveData);
|
||||
tmp = ror(bus.read(effectiveAddress));
|
||||
bus.write(effectiveAddress, tmp);
|
||||
setArithmeticFlags(tmp);
|
||||
break;
|
||||
@@ -562,59 +562,72 @@ public class Cpu implements InstructionTable {
|
||||
|
||||
|
||||
/** LDY - Load Y Register ***********************************************/
|
||||
case 0xa0: // Immediate
|
||||
case 0xa0: // #Immediate
|
||||
y = args[0];
|
||||
setArithmeticFlags(y);
|
||||
break;
|
||||
case 0xa4: // Zero Page
|
||||
case 0xac: // Absolute
|
||||
case 0xb4: // Zero Page,X
|
||||
case 0xbc: // Absolute,X
|
||||
y = effectiveData;
|
||||
y = bus.read(effectiveAddress);
|
||||
setArithmeticFlags(y);
|
||||
break;
|
||||
|
||||
|
||||
/** LDX - Load X Register ***********************************************/
|
||||
case 0xa2: // Immediate
|
||||
case 0xa2: // #Immediate
|
||||
x = args[0];
|
||||
setArithmeticFlags(x);
|
||||
break;
|
||||
case 0xa6: // Zero Page
|
||||
case 0xae: // Absolute
|
||||
case 0xb6: // Zero Page,Y
|
||||
case 0xbe: // Absolute,Y
|
||||
x = effectiveData;
|
||||
x = bus.read(effectiveAddress);
|
||||
setArithmeticFlags(x);
|
||||
break;
|
||||
|
||||
|
||||
/** LDA - Load Accumulator **********************************************/
|
||||
case 0xa9: // #Immediate
|
||||
a = args[0];
|
||||
setArithmeticFlags(a);
|
||||
break;
|
||||
case 0xa1: // (Zero Page,X)
|
||||
case 0xa5: // Zero Page
|
||||
case 0xa9: // Immediate
|
||||
case 0xad: // Absolute
|
||||
case 0xb1: // (Zero Page),Y
|
||||
case 0xb5: // Zero Page,X
|
||||
case 0xb9: // Absolute,Y
|
||||
case 0xbd: // Absolute,X
|
||||
a = effectiveData;
|
||||
a = bus.read(effectiveAddress);
|
||||
setArithmeticFlags(a);
|
||||
break;
|
||||
|
||||
|
||||
/** CPY - Compare Y Register ********************************************/
|
||||
case 0xc0: // Immediate
|
||||
case 0xc0: // #Immediate
|
||||
cmp(y, args[0]);
|
||||
break;
|
||||
case 0xc4: // Zero Page
|
||||
case 0xcc: // Absolute
|
||||
cmp(y, effectiveData);
|
||||
cmp(y, bus.read(effectiveAddress));
|
||||
break;
|
||||
|
||||
|
||||
/** CMP - Compare Accumulator *******************************************/
|
||||
case 0xc9: // #Immediate
|
||||
cmp(a, args[0]);
|
||||
break;
|
||||
case 0xc1: // (Zero Page,X)
|
||||
case 0xc5: // Zero Page
|
||||
case 0xc9: // #Immediate
|
||||
case 0xcd: // Absolute
|
||||
case 0xd1: // (Zero Page),Y
|
||||
case 0xd5: // Zero Page,X
|
||||
case 0xd9: // Absolute,Y
|
||||
case 0xdd: // Absolute,X
|
||||
cmp(a, effectiveData);
|
||||
cmp(a, bus.read(effectiveAddress));
|
||||
break;
|
||||
|
||||
|
||||
@@ -623,33 +636,41 @@ public class Cpu implements InstructionTable {
|
||||
case 0xce: // Absolute
|
||||
case 0xd6: // Zero Page,X
|
||||
case 0xde: // Absolute,X
|
||||
tmp = --effectiveData & 0xff;
|
||||
tmp = (bus.read(effectiveAddress) - 1) & 0xff;
|
||||
bus.write(effectiveAddress, tmp);
|
||||
setArithmeticFlags(tmp);
|
||||
break;
|
||||
|
||||
|
||||
/** CPX - Compare X Register ********************************************/
|
||||
case 0xe0: // Immediate
|
||||
case 0xe0: // #Immediate
|
||||
cmp(x, args[0]);
|
||||
break;
|
||||
case 0xe4: // Zero Page
|
||||
case 0xec: // Absolute
|
||||
cmp(x, effectiveData);
|
||||
cmp(x, bus.read(effectiveAddress));
|
||||
break;
|
||||
|
||||
|
||||
/** SBC - Subtract with Carry (Borrow) **********************************/
|
||||
case 0xe9: // #Immediate
|
||||
if (decimalModeFlag) {
|
||||
a = sbcDecimal(a, args[0]);
|
||||
} else {
|
||||
a = sbc(a, args[0]);
|
||||
}
|
||||
break;
|
||||
case 0xe1: // (Zero Page,X)
|
||||
case 0xe5: // Zero Page
|
||||
case 0xe9: // Immediate
|
||||
case 0xed: // Absolute
|
||||
case 0xf1: // (Zero Page),Y
|
||||
case 0xf5: // Zero Page,X
|
||||
case 0xf9: // Absolute,Y
|
||||
case 0xfd: // Absolute,X
|
||||
if (decimalModeFlag) {
|
||||
a = sbcDecimal(a, effectiveData);
|
||||
a = sbcDecimal(a, bus.read(effectiveAddress));
|
||||
} else {
|
||||
a = sbc(a, effectiveData);
|
||||
a = sbc(a, bus.read(effectiveAddress));
|
||||
}
|
||||
break;
|
||||
|
||||
@@ -659,7 +680,7 @@ public class Cpu implements InstructionTable {
|
||||
case 0xee: // Absolute
|
||||
case 0xf6: // Zero Page,X
|
||||
case 0xfe: // Absolute,X
|
||||
tmp = ++effectiveData & 0xff;
|
||||
tmp = (bus.read(effectiveAddress) + 1) & 0xff;
|
||||
bus.write(effectiveAddress, tmp);
|
||||
setArithmeticFlags(tmp);
|
||||
break;
|
||||
|
||||
Reference in new issue
Block a user