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More implied mode instructions implemented, with tests.

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This commit is contained in:
Seth J. Morabito 2008-12-23 16:06:09 -08:00
parent 473b47e832
commit f012ba7775
2 changed files with 327 additions and 12 deletions
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47
src/main/java/com/loomcom/symon/Cpu.java
View File

@ -96,6 +96,8 @@ public class Cpu implements InstructionTable {
* Performs an individual machine cycle.
*/
public void step() {
int lo, hi; // Used in address calculation
// Store the address from which the IR was read, for debugging
addr = pc;
@ -143,7 +145,8 @@ public class Cpu implements InstructionTable {
break;
case 0x07: // n/a
break;
case 0x08: // n/a
case 0x08: // PHP - Push Processor Status - Implied
stackPush(getProcessorStatus());
break;
case 0x09: // ORA - Immediate
a |= operands[0];
@ -212,7 +215,8 @@ public class Cpu implements InstructionTable {
break;
case 0x27: // n/a
break;
case 0x28: // n/a
case 0x28: // PLP - Pull Processor Status - Implied
setProcessorStatus(stackPop());
break;
case 0x29: // n/a
a &= operands[0];
@ -265,7 +269,11 @@ public class Cpu implements InstructionTable {
case 0x3f: // n/a
break;
case 0x40: // n/a
case 0x40: // RTI - Return from Interrupt - Implied
setProcessorStatus(stackPop());
lo = stackPop();
hi = stackPop();
setProgramCounter(CpuUtils.address(lo, hi));
break;
case 0x41: // n/a
break;
@ -281,7 +289,8 @@ public class Cpu implements InstructionTable {
break;
case 0x47: // n/a
break;
case 0x48: // n/a
case 0x48: // PHA - Push Accumulator - Implied
stackPush(a);
break;
case 0x49: // EOR - Immediate
a ^= operands[0];
@ -317,7 +326,7 @@ public class Cpu implements InstructionTable {
break;
case 0x57: // n/a
break;
case 0x58: // CLI - Clear Interrupt Disable, Implied
case 0x58: // CLI - Clear Interrupt Disable - Implied
clearIrqDisableFlag();
break;
case 0x59: // n/a
@ -335,7 +344,11 @@ public class Cpu implements InstructionTable {
case 0x5f: // n/a
break;
case 0x60: // n/a
case 0x60: // RTS - Return from Subrouting - Implied
lo = stackPop();
hi = stackPop();
setProgramCounter((CpuUtils.address(lo, hi) - 1) & 0xffff);
break;
case 0x61: // n/a
break;
@ -351,7 +364,9 @@ public class Cpu implements InstructionTable {
break;
case 0x67: // n/a
break;
case 0x68: // n/a
case 0x68: // PLA - Pull Accumulator - Implied
a = stackPop();
setArithmeticFlags(a);
break;
case 0x69: // ADC - Immediate Mode
a = adc(a, operands[0]);
@ -420,7 +435,9 @@ public class Cpu implements InstructionTable {
break;
case 0x87: // n/a
break;
case 0x88: // n/a
case 0x88: // DEY - Decrement the Y Register - Implied
y = --y & 0xff;
setArithmeticFlags(y);
break;
case 0x89: // n/a
break;
@ -560,12 +577,16 @@ public class Cpu implements InstructionTable {
break;
case 0xc7: // n/a
break;
case 0xc8: // n/a
case 0xc8: // INY - Increment the Y Register - Implied
y = ++y & 0xff;
setArithmeticFlags(y);
break;
case 0xc9: // CMP - Immediate
cmp(a, operands[0]);
break;
case 0xca: // n/a
case 0xca: // DEX - Decrement the X Register - Implied
x = --x & 0xff;
setArithmeticFlags(x);
break;
case 0xcb: // n/a
break;
@ -629,9 +650,11 @@ public class Cpu implements InstructionTable {
break;
case 0xe7: // n/a
break;
case 0xe8: // n/a
case 0xe8: // INX - Increment X Register - Implied
x = ++x & 0xff;
setArithmeticFlags(x);
break;
case 0xe9: // n/a
case 0xe9: // SBC - Subtract with Carry (Borrow) - Immediate
a = sbc(a, operands[0]);
setArithmeticFlags(a);
break;

292
src/test/java/com/loomcom/symon/CpuImpliedModeTest.java
View File

@ -22,6 +22,14 @@ public class CpuImpliedModeTest extends TestCase {
bus.write(0xfffd, (Cpu.DEFAULT_BASE_ADDRESS & 0xff00)>>>8);
cpu.reset();
// Assert initial state
assertEquals(0, cpu.getAccumulator());
assertEquals(0, cpu.getXRegister());
assertEquals(0, cpu.getYRegister());
assertEquals(0x200, cpu.getProgramCounter());
assertEquals(0xff, cpu.getStackPointer());
assertEquals(0x20, cpu.getProcessorStatus());
}
/*
@ -127,4 +135,288 @@ public class CpuImpliedModeTest extends TestCase {
assertEquals(0xff, cpu.getStackPointer());
}
/* CLC - Clear Carry Flag - $18 */
public void test_CLC() {
cpu.setCarryFlag();
assertTrue(cpu.getCarryFlag());
bus.loadProgram(0x18);
cpu.step();
assertFalse(cpu.getCarryFlag());
}
/* CLD - Clear Decimal Mode Flag - $d8 */
public void test_CLD() {
cpu.setDecimalModeFlag();
assertTrue(cpu.getDecimalModeFlag());
bus.loadProgram(0xd8);
cpu.step();
assertFalse(cpu.getDecimalModeFlag());
}
/* CLI - Clear Interrupt Disabled Flag - $58 */
public void test_CLI() {
cpu.setIrqDisableFlag();
assertTrue(cpu.getIrqDisableFlag());
bus.loadProgram(0x58);
cpu.step();
assertFalse(cpu.getIrqDisableFlag());
}
/* CLV - Clear Overflow Flag - $b8 */
public void test_CLV() {
cpu.setOverflowFlag();
assertTrue(cpu.getOverflowFlag());
bus.loadProgram(0xb8);
cpu.step();
assertFalse(cpu.getOverflowFlag());
}
/* DEX - Decrement the X register - $ca */
public void test_DEX() {
bus.loadProgram(0xca);
cpu.setXRegister(0x02);
cpu.step();
assertEquals(0x01, cpu.getXRegister());
assertFalse(cpu.getZeroFlag());
assertFalse(cpu.getNegativeFlag());
}
public void test_DEX_SetsZeroFlagWhenZero() {
bus.loadProgram(0xca);
cpu.setXRegister(0x01);
cpu.step();
assertEquals(0x00, cpu.getXRegister());
assertTrue(cpu.getZeroFlag());
assertFalse(cpu.getNegativeFlag());
}
public void test_DEX_SetsNegativeFlagWhen() {
bus.loadProgram(0xca);
cpu.step();
assertEquals(0xff, cpu.getXRegister());
assertFalse(cpu.getZeroFlag());
assertTrue(cpu.getNegativeFlag());
}
/* DEY - Decrement the Y register - $88 */
public void test_DEY() {
bus.loadProgram(0x88);
cpu.setYRegister(0x02);
cpu.step();
assertEquals(0x01, cpu.getYRegister());
assertFalse(cpu.getZeroFlag());
assertFalse(cpu.getNegativeFlag());
}
public void test_DEY_SetsZeroFlagWhenZero() {
bus.loadProgram(0x88);
cpu.setYRegister(0x01);
cpu.step();
assertEquals(0x00, cpu.getYRegister());
assertTrue(cpu.getZeroFlag());
assertFalse(cpu.getNegativeFlag());
}
public void test_DEY_SetsNegativeFlagWhen() {
bus.loadProgram(0x88);
cpu.step();
assertEquals(0xff, cpu.getYRegister());
assertFalse(cpu.getZeroFlag());
assertTrue(cpu.getNegativeFlag());
}
/* INX - Increment the X register - $e8 */
public void test_INX() {
bus.loadProgram(0xe8);
cpu.step();
assertEquals(0x01, cpu.getXRegister());
assertFalse(cpu.getZeroFlag());
assertFalse(cpu.getNegativeFlag());
}
public void test_INX_SetsNegativeFlagWhenNegative() {
bus.loadProgram(0xe8);
cpu.setXRegister(0x7f);
cpu.step();
assertEquals(0x80, cpu.getXRegister());
assertFalse(cpu.getZeroFlag());
assertTrue(cpu.getNegativeFlag());
}
public void test_INX_SetsZeroFlagWhenZero() {
bus.loadProgram(0xe8);
cpu.setXRegister(0xff);
cpu.step();
assertEquals(0x00, cpu.getXRegister());
assertTrue(cpu.getZeroFlag());
assertFalse(cpu.getNegativeFlag());
}
/* INY - Increment the Y register - $c8 */
public void test_INY() {
bus.loadProgram(0xc8);
cpu.step();
assertEquals(0x01, cpu.getYRegister());
assertFalse(cpu.getZeroFlag());
assertFalse(cpu.getNegativeFlag());
}
public void test_INY_SetsNegativeFlagWhenNegative() {
bus.loadProgram(0xc8);
cpu.setYRegister(0x7f);
cpu.step();
assertEquals(0x80, cpu.getYRegister());
assertFalse(cpu.getZeroFlag());
assertTrue(cpu.getNegativeFlag());
}
public void test_INY_SetsZeroFlagWhenZero() {
bus.loadProgram(0xc8);
cpu.setYRegister(0xff);
cpu.step();
assertEquals(0x00, cpu.getYRegister());
assertTrue(cpu.getZeroFlag());
assertFalse(cpu.getNegativeFlag());
}
/* NOP - No Operation - $ea */
public void test_NOP() {
bus.loadProgram(0xea);
cpu.step();
// Should just not change anything except PC
assertEquals(0, cpu.getAccumulator());
assertEquals(0, cpu.getXRegister());
assertEquals(0, cpu.getYRegister());
assertEquals(0x201, cpu.getProgramCounter());
assertEquals(0xff, cpu.getStackPointer());
assertEquals(0x20, cpu.getProcessorStatus());
}
/* PHA - Push Accumulator - $48 */
public void test_PHA() {
bus.loadProgram(0x48);
cpu.setAccumulator(0x3a);
cpu.step();
assertEquals(0xfe, cpu.getStackPointer());
assertEquals(0x3a, cpu.stackPeek());
}
/* PHP - Push Processor Status - $08 */
public void test_PHP() {
bus.loadProgram(0x08);
cpu.setProcessorStatus(0x27);
cpu.step();
assertEquals(0xfe, cpu.getStackPointer());
assertEquals(0x27, cpu.stackPeek());
}
/* PLA - Pul Accumulator - $68 */
public void test_PLA() {
cpu.stackPush(0x32);
bus.loadProgram(0x68);
cpu.step();
assertEquals(0x32, cpu.getAccumulator());
assertFalse(cpu.getNegativeFlag());
assertFalse(cpu.getZeroFlag());
}
public void test_PLA_SetsZeroIfAccumulatorIsZero() {
cpu.stackPush(0x00);
bus.loadProgram(0x68);
cpu.step();
assertEquals(0x00, cpu.getAccumulator());
assertFalse(cpu.getNegativeFlag());
assertTrue(cpu.getZeroFlag());
}
public void test_PLA_SetsNegativeIfAccumulatorIsNegative() {
cpu.stackPush(0xff);
bus.loadProgram(0x68);
cpu.step();
assertEquals(0xff, cpu.getAccumulator());
assertTrue(cpu.getNegativeFlag());
assertFalse(cpu.getZeroFlag());
}
/* PLP - Pull Processor Status - $28 */
public void test_PLP() {
cpu.stackPush(0x2f);
bus.loadProgram(0x28);
cpu.step();
assertEquals(0x2f, cpu.getProcessorStatus());
}
/* RTI - Return from Interrupt - $40 */
public void test_RTI() {
cpu.stackPush(0x0f); // PC hi
cpu.stackPush(0x11); // PC lo
cpu.stackPush(0x29); // status
bus.loadProgram(0x40);
cpu.step();
assertEquals(0x0f11, cpu.getProgramCounter());
assertEquals(0x29, cpu.getProcessorStatus());
}
/* RTS - Return from Subroutine - $60 */
public void test_RTS() {
cpu.stackPush(0x0f); // PC hi
cpu.stackPush(0x11); // PC lo
bus.loadProgram(0x60);
cpu.step();
assertEquals(0x0f10, cpu.getProgramCounter());
assertEquals(0x20, cpu.getProcessorStatus());
}
/* SEC - Set Carry Flag - $38 */
public void test_SEC() {
bus.loadProgram(0x38);
cpu.step();
assertTrue(cpu.getCarryFlag());
}
/* SED - Set Decimal Mode Flag - $f8 */
public void test_SED() {
bus.loadProgram(0xf8);
cpu.step();
assertTrue(cpu.getDecimalModeFlag());
}
/* SEI - Set Interrupt Disable Flag - $78 */
public void test_SEI() {
bus.loadProgram(0x78);
cpu.step();
assertTrue(cpu.getIrqDisableFlag());
}
/* TAX - - $aa */
public void test_TAX() {
}
}