Seth Morabito
2ebdd254b3
This is something of a "Work in Progress" checkpoint of several features that are all half baked: 1. Allow loading of 16KB ROM files at address $C000 at run-time, not just at startup. See the "Load ROM..." File menu item. 2. Introduces the notion of "CPU Behaviors", so the core 6502 CPU implementation can match the behavior of either an early NMOS 6502, late NMOS 6502, or CMOS 65C02. Very little of this is actually implemented so far. 3. Adds a completely bogus implementation of the 6522 VIA (it does absolutely nothing right now). 4. Changes the address of the ACIA in the simulated system to match a real hardware implementation I put together.
710 lines
23 KiB
Java
710 lines
23 KiB
Java
package com.loomcom.symon;
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import com.loomcom.symon.devices.Memory;
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import com.loomcom.symon.exceptions.MemoryAccessException;
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import junit.framework.TestCase;
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public class CpuIndirectXModeTest extends TestCase {
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protected Cpu cpu;
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protected Bus bus;
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protected Memory mem;
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protected void setUp() throws Exception {
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this.cpu = new Cpu();
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this.bus = new Bus(0x0000, 0xffff);
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this.mem = new Memory(0x0000, 0x10000);
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bus.addCpu(cpu);
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bus.addDevice(mem);
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// Load the reset vector.
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bus.write(0xfffc, Bus.DEFAULT_LOAD_ADDRESS & 0x00ff);
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bus.write(0xfffd, (Bus.DEFAULT_LOAD_ADDRESS & 0xff00) >>> 8);
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cpu.reset();
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// Assert initial state
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assertEquals(0, cpu.getAccumulator());
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assertEquals(0, cpu.getXRegister());
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assertEquals(0, cpu.getYRegister());
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assertEquals(0x200, cpu.getProgramCounter());
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assertEquals(0xff, cpu.getStackPointer());
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assertEquals(0x20, cpu.getProcessorStatus());
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}
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/*
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* The following opcodes are tested for correctness in this file:
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*
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* ORA - $01
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* AND - $21
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* EOR - $41
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* ADC - $61
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* STA - $81
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*
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* LDA - $a1
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* CMP - $c1
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* SBC - $e1
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*
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*/
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/* ORA - Logical Inclusive OR - $1d */
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public void test_ORA() throws MemoryAccessException {
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// Set some initial values in memory
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bus.write(0x2c30, 0x00);
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bus.write(0x2c32, 0x11);
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bus.write(0x2c34, 0x22);
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bus.write(0x2c38, 0x44);
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bus.write(0x2c40, 0x88);
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// Set offset in X register.
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cpu.setXRegister(0x30);
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bus.loadProgram(0x1d, 0x00, 0x2c, // ORA $2c00,X
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0x1d, 0x02, 0x2c, // ORA $2c02,X
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0x1d, 0x04, 0x2c, // ORA $2c04,X
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0x1d, 0x08, 0x2c, // ORA $2c08,X
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0x1d, 0x10, 0x2c); // ORA $2c10,X
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cpu.step();
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assertEquals(0x00, cpu.getAccumulator());
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assertTrue(cpu.getZeroFlag());
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assertFalse(cpu.getNegativeFlag());
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cpu.step();
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assertEquals(0x11, cpu.getAccumulator());
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assertFalse(cpu.getZeroFlag());
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assertFalse(cpu.getNegativeFlag());
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cpu.step();
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assertEquals(0x33, cpu.getAccumulator());
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assertFalse(cpu.getZeroFlag());
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assertFalse(cpu.getNegativeFlag());
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cpu.step();
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assertEquals(0x77, cpu.getAccumulator());
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assertFalse(cpu.getZeroFlag());
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assertFalse(cpu.getNegativeFlag());
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cpu.step();
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assertEquals(0xff, cpu.getAccumulator());
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assertFalse(cpu.getZeroFlag());
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assertTrue(cpu.getNegativeFlag());
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}
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/* AND - Logical AND - $3d */
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public void test_AND() throws MemoryAccessException {
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bus.write(0x1a30, 0x00);
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bus.write(0x1a31, 0x11);
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bus.write(0x1a32, 0xff);
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bus.write(0x1a33, 0x99);
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bus.write(0x1a34, 0x11);
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bus.write(0x1a35, 0x0f);
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bus.write(0x1a02, 0x11);
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// Set offset in X register.
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cpu.setXRegister(0x30);
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bus.loadProgram(0x3d, 0x00, 0x1a, // AND $1a00,X
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0x3d, 0x01, 0x1a, // AND $1a01,X
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0xa9, 0xaa, // LDA #$aa
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0x3d, 0x02, 0x1a, // AND $1a02,X
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0x3d, 0x03, 0x1a, // AND $1a03,X
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0x3d, 0x04, 0x1a, // AND $1a04,X
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0xa9, 0xff, // LDA #$ff
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0x3d, 0x05, 0x1a, // AND $1a05,X
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0xa9, 0x01, // LDA #$01
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0x3d, 0xd2, 0x19); // AND $19d2,X
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cpu.step();
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assertEquals(0x00, cpu.getAccumulator());
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assertTrue(cpu.getZeroFlag());
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assertFalse(cpu.getNegativeFlag());
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cpu.step();
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assertEquals(0x00, cpu.getAccumulator());
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assertTrue(cpu.getZeroFlag());
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assertFalse(cpu.getNegativeFlag());
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cpu.step(2);
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assertEquals(0xaa, cpu.getAccumulator());
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assertFalse(cpu.getZeroFlag());
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assertTrue(cpu.getNegativeFlag());
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cpu.step();
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assertEquals(0x88, cpu.getAccumulator());
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assertFalse(cpu.getZeroFlag());
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assertTrue(cpu.getNegativeFlag());
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cpu.step();
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assertEquals(0x00, cpu.getAccumulator());
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assertTrue(cpu.getZeroFlag());
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assertFalse(cpu.getNegativeFlag());
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cpu.step(2);
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assertEquals(0x0f, cpu.getAccumulator());
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assertFalse(cpu.getZeroFlag());
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assertFalse(cpu.getNegativeFlag());
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cpu.step(2);
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assertEquals(0x01, cpu.getAccumulator());
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assertFalse(cpu.getZeroFlag());
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assertFalse(cpu.getNegativeFlag());
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}
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/* EOR - Exclusive OR - $5d */
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public void test_EOR() throws MemoryAccessException {
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bus.write(0xab40, 0x00);
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bus.write(0xab41, 0xff);
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bus.write(0xab42, 0x33);
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bus.write(0xab43, 0x44);
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cpu.setXRegister(0x30);
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bus.loadProgram(0xa9, 0x88, // LDA #$88
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0x5d, 0x10, 0xab, // EOR $ab10,X
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0x5d, 0x11, 0xab, // EOR $ab11,X
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0x5d, 0x12, 0xab, // EOR $ab12,X
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0x5d, 0x13, 0xab); // EOR $ab13,X
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cpu.step(2);
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assertEquals(0x88, cpu.getAccumulator());
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assertTrue(cpu.getNegativeFlag());
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assertFalse(cpu.getZeroFlag());
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cpu.step();
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assertEquals(0x77, cpu.getAccumulator());
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assertFalse(cpu.getNegativeFlag());
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assertFalse(cpu.getZeroFlag());
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cpu.step();
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assertEquals(0x44, cpu.getAccumulator());
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assertFalse(cpu.getNegativeFlag());
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assertFalse(cpu.getZeroFlag());
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cpu.step();
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assertEquals(0x00, cpu.getAccumulator());
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assertFalse(cpu.getNegativeFlag());
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assertTrue(cpu.getZeroFlag());
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}
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/* ADC - Add with Carry - $7d */
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public void test_ADC() throws MemoryAccessException {
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bus.write(0xab40, 0x01);
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bus.write(0xab41, 0xff);
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cpu.setXRegister(0x30);
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bus.loadProgram(0xa9, 0x00, // LDA #$00
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0x7d, 0x10, 0xab); // ADC $ab10,X
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cpu.step(2);
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assertEquals(0x01, cpu.getAccumulator());
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assertFalse(cpu.getNegativeFlag());
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assertFalse(cpu.getOverflowFlag());
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assertFalse(cpu.getZeroFlag());
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assertFalse(cpu.getCarryFlag());
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cpu.reset();
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cpu.setXRegister(0x30);
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bus.loadProgram(0xa9, 0x7f, // LDA #$7f
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0x7d, 0x10, 0xab); // ADC $ab10,X
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cpu.step(2);
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assertEquals(0x80, cpu.getAccumulator());
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assertTrue(cpu.getNegativeFlag());
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assertTrue(cpu.getOverflowFlag());
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assertFalse(cpu.getZeroFlag());
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assertFalse(cpu.getCarryFlag());
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cpu.reset();
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cpu.setXRegister(0x30);
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bus.loadProgram(0xa9, 0x80, // LDA #$80
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0x7d, 0x10, 0xab); // ADC $ab10,X
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cpu.step(2);
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assertEquals(0x81, cpu.getAccumulator());
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assertTrue(cpu.getNegativeFlag());
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assertFalse(cpu.getOverflowFlag());
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assertFalse(cpu.getZeroFlag());
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assertFalse(cpu.getCarryFlag());
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cpu.reset();
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cpu.setXRegister(0x30);
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bus.loadProgram(0xa9, 0xff, // LDA #$ff
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0x7d, 0x10, 0xab); // ADC $ab10,X
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cpu.step(2);
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assertEquals(0x00, cpu.getAccumulator());
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assertFalse(cpu.getNegativeFlag());
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assertFalse(cpu.getOverflowFlag());
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assertTrue(cpu.getZeroFlag());
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assertTrue(cpu.getCarryFlag());
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cpu.reset();
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cpu.setXRegister(0x30);
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bus.loadProgram(0xa9, 0x00, // LDA #$00
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0x7d, 0x11, 0xab); // ADC $ab11,X
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cpu.step(2);
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assertEquals(0xff, cpu.getAccumulator());
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assertTrue(cpu.getNegativeFlag());
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assertFalse(cpu.getOverflowFlag());
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assertFalse(cpu.getZeroFlag());
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assertFalse(cpu.getCarryFlag());
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cpu.reset();
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cpu.setXRegister(0x30);
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bus.loadProgram(0xa9, 0x7f, // LDA #$7f
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0x7d, 0x11, 0xab); // ADC $ab11,X
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cpu.step(2);
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assertEquals(0x7e, cpu.getAccumulator());
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assertFalse(cpu.getNegativeFlag());
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assertFalse(cpu.getOverflowFlag());
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assertFalse(cpu.getZeroFlag());
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assertTrue(cpu.getCarryFlag());
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cpu.reset();
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cpu.setXRegister(0x30);
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bus.loadProgram(0xa9, 0x80, // LDA #$80
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0x7d, 0x11, 0xab); // ADC $ab11,X
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cpu.step(2);
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assertEquals(0x7f, cpu.getAccumulator());
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assertFalse(cpu.getNegativeFlag());
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assertTrue(cpu.getOverflowFlag());
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assertFalse(cpu.getZeroFlag());
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assertTrue(cpu.getCarryFlag());
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cpu.reset();
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cpu.setXRegister(0x30);
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bus.loadProgram(0xa9, 0xff, // LDA #$ff
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0x7d, 0x11, 0xab); // ADC $ab11,X
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cpu.step(2);
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assertEquals(0xfe, cpu.getAccumulator());
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assertTrue(cpu.getNegativeFlag());
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assertFalse(cpu.getOverflowFlag());
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assertFalse(cpu.getZeroFlag());
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assertTrue(cpu.getCarryFlag());
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}
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public void test_ADC_IncludesCarry() throws MemoryAccessException {
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bus.write(0xab40, 0x01);
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bus.loadProgram(0xa9, 0x00, // LDA #$00
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0x38, // SEC
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0x7d, 0x10, 0xab); // ADC $ab10,X
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cpu.setXRegister(0x30);
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cpu.step(3);
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assertEquals(0x02, cpu.getAccumulator());
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assertFalse(cpu.getNegativeFlag());
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assertFalse(cpu.getOverflowFlag());
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assertFalse(cpu.getZeroFlag());
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assertFalse(cpu.getCarryFlag());
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}
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public void test_ADC_DecimalMode() throws MemoryAccessException {
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bus.write(0xab40, 0x01);
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bus.write(0xab41, 0x99);
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bus.loadProgram(0xf8, // SED
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0xa9, 0x01, // LDA #$01
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0x7d, 0x10, 0xab); // ADC $ab10,X
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cpu.setXRegister(0x30);
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cpu.step(3);
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assertEquals(0x02, cpu.getAccumulator());
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assertFalse(cpu.getNegativeFlag());
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assertFalse(cpu.getOverflowFlag());
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assertFalse(cpu.getZeroFlag());
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assertFalse(cpu.getCarryFlag());
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cpu.reset();
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cpu.setXRegister(0x30);
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bus.loadProgram(0xf8, // SED
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0xa9, 0x49, // LDA #$49
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0x7d, 0x10, 0xab); // ADC $ab10,X
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cpu.step(3);
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assertEquals(0x50, cpu.getAccumulator());
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assertFalse(cpu.getNegativeFlag());
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assertFalse(cpu.getOverflowFlag());
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assertFalse(cpu.getZeroFlag());
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assertFalse(cpu.getCarryFlag());
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cpu.reset();
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cpu.setXRegister(0x30);
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bus.loadProgram(0xf8, // SED
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0xa9, 0x50, // LDA #$50
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0x7d, 0x10, 0xab); // ADC $ab10,X
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cpu.step(3);
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assertEquals(0x51, cpu.getAccumulator());
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assertFalse(cpu.getNegativeFlag());
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assertFalse(cpu.getOverflowFlag());
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assertFalse(cpu.getZeroFlag());
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assertFalse(cpu.getCarryFlag());
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cpu.reset();
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cpu.setXRegister(0x30);
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bus.loadProgram(0xf8, // SED
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0xa9, 0x99, // LDA #$99
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0x7d, 0x10, 0xab); // ADC $ab10,X
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cpu.step(3);
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assertEquals(0x00, cpu.getAccumulator());
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assertFalse(cpu.getNegativeFlag());
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assertFalse(cpu.getOverflowFlag());
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assertTrue(cpu.getZeroFlag());
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assertTrue(cpu.getCarryFlag());
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cpu.reset();
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cpu.setXRegister(0x30);
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bus.loadProgram(0xf8, // SED
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0xa9, 0x00, // LDA #$00
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0x7d, 0x11, 0xab); // ADC $ab10,X
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cpu.step(3);
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assertEquals(0x99, cpu.getAccumulator());
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assertFalse(cpu.getNegativeFlag());
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assertFalse(cpu.getOverflowFlag());
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assertFalse(cpu.getZeroFlag());
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assertFalse(cpu.getCarryFlag());
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cpu.reset();
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cpu.setXRegister(0x30);
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bus.loadProgram(0xf8, // SED
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0xa9, 0x49, // LDA #$49
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0x7d, 0x11, 0xab); // ADC $ab11,X
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cpu.step(3);
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assertEquals(0x48, cpu.getAccumulator());
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assertFalse(cpu.getNegativeFlag());
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assertFalse(cpu.getOverflowFlag());
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assertFalse(cpu.getZeroFlag());
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assertTrue(cpu.getCarryFlag());
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cpu.reset();
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cpu.setXRegister(0x30);
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bus.loadProgram(0xf8, // SED
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0xa9, 0x50, // LDA #$59
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0x7d, 0x11, 0xab); // ADC $ab11,X
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cpu.step(3);
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assertEquals(0x49, cpu.getAccumulator());
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assertFalse(cpu.getNegativeFlag());
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assertFalse(cpu.getOverflowFlag());
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assertFalse(cpu.getZeroFlag());
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assertTrue(cpu.getCarryFlag());
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}
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/* STA - Store Accumulator - $9d */
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public void test_STA() throws MemoryAccessException {
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cpu.setXRegister(0x30);
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cpu.setAccumulator(0x00);
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bus.loadProgram(0x9d, 0x10, 0xab); // STA $ab10,X
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cpu.step();
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assertEquals(0x00, bus.read(0xab40));
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assertFalse(cpu.getZeroFlag());
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assertFalse(cpu.getNegativeFlag());
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cpu.reset();
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cpu.setXRegister(0x30);
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cpu.setAccumulator(0x0f);
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bus.loadProgram(0x9d, 0x10, 0xab); // STA $ab10,X
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cpu.step();
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assertEquals(0x0f, bus.read(0xab40));
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assertFalse(cpu.getZeroFlag());
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assertFalse(cpu.getNegativeFlag());
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cpu.reset();
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cpu.setXRegister(0x30);
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cpu.setAccumulator(0x80);
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bus.loadProgram(0x9d, 0x10, 0xab); // STA $ab10,X
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cpu.step();
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assertEquals(0x80, bus.read(0xab40));
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assertFalse(cpu.getZeroFlag());
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assertFalse(cpu.getNegativeFlag());
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}
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/* LDA - Load Accumulator - $bd */
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public void test_LDA() throws MemoryAccessException {
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bus.write(0xab42, 0x00);
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bus.write(0xab43, 0x0f);
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bus.write(0xab44, 0x80);
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bus.loadProgram(0xbd, 0x10, 0xab, // LDA $ab10,X
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0xbd, 0x11, 0xab, // LDA $ab11,X
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0xbd, 0x12, 0xab); // LDA $ab12,X
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cpu.setXRegister(0x32);
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cpu.step();
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assertEquals(0x00, cpu.getAccumulator());
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assertTrue(cpu.getZeroFlag());
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assertFalse(cpu.getNegativeFlag());
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cpu.step();
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assertEquals(0x0f, cpu.getAccumulator());
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assertFalse(cpu.getZeroFlag());
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assertFalse(cpu.getNegativeFlag());
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cpu.step();
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assertEquals(0x80, cpu.getAccumulator());
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assertFalse(cpu.getZeroFlag());
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assertTrue(cpu.getNegativeFlag());
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}
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/* CMP - Compare Accumulator - $dd */
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public void test_CMP() throws MemoryAccessException {
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bus.write(0xab40, 0x00);
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bus.write(0xab41, 0x80);
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bus.write(0xab42, 0xff);
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cpu.setAccumulator(0x80);
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bus.loadProgram(0xdd, 0x10, 0xab, // CMP $ab10,X
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0xdd, 0x11, 0xab, // CMP $ab11,X
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0xdd, 0x12, 0xab); // CMP $ab12,X
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cpu.setXRegister(0x30);
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cpu.step();
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assertTrue(cpu.getCarryFlag()); // m > y
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assertFalse(cpu.getZeroFlag());
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assertTrue(cpu.getNegativeFlag()); // m - y < 0
|
|
|
|
cpu.step();
|
|
assertTrue(cpu.getCarryFlag()); // m = y
|
|
assertTrue(cpu.getZeroFlag());
|
|
assertFalse(cpu.getNegativeFlag()); // m - y == 0
|
|
|
|
cpu.step();
|
|
assertFalse(cpu.getCarryFlag()); // m < y
|
|
assertFalse(cpu.getZeroFlag());
|
|
assertTrue(cpu.getNegativeFlag()); // m - y < 0
|
|
}
|
|
|
|
/* SBC - Subtract with Carry - $fd */
|
|
|
|
public void test_SBC() throws MemoryAccessException {
|
|
bus.write(0xab40, 0x01);
|
|
|
|
bus.loadProgram(0xa9, 0x00, // LDA #$00
|
|
0xfd, 0x10, 0xab); // SBC $ab10,X
|
|
cpu.setXRegister(0x30);
|
|
cpu.step(2);
|
|
assertEquals(0xfe, cpu.getAccumulator());
|
|
assertTrue(cpu.getNegativeFlag());
|
|
assertFalse(cpu.getOverflowFlag());
|
|
assertFalse(cpu.getZeroFlag());
|
|
assertFalse(cpu.getCarryFlag());
|
|
|
|
cpu.reset();
|
|
bus.loadProgram(0xa9, 0x7f, // LDA #$7f
|
|
0xfd, 0x10, 0xab); // SBC $ab10,X
|
|
cpu.setXRegister(0x30);
|
|
cpu.step(2);
|
|
assertEquals(0x7d, cpu.getAccumulator());
|
|
assertFalse(cpu.getNegativeFlag());
|
|
assertFalse(cpu.getOverflowFlag());
|
|
assertFalse(cpu.getZeroFlag());
|
|
assertTrue(cpu.getCarryFlag());
|
|
|
|
cpu.reset();
|
|
bus.loadProgram(0xa9, 0x80, // LDA #$80
|
|
0xfd, 0x10, 0xab); // SBC $ab10,X
|
|
cpu.setXRegister(0x30);
|
|
cpu.step(2);
|
|
assertEquals(0x7e, cpu.getAccumulator());
|
|
assertFalse(cpu.getNegativeFlag());
|
|
assertTrue(cpu.getOverflowFlag());
|
|
assertFalse(cpu.getZeroFlag());
|
|
assertTrue(cpu.getCarryFlag());
|
|
|
|
cpu.reset();
|
|
bus.loadProgram(0xa9, 0xff, // LDA #$ff
|
|
0xfd, 0x10, 0xab); // SBC $ab10,X
|
|
cpu.setXRegister(0x30);
|
|
cpu.step(2);
|
|
assertEquals(0xfd, cpu.getAccumulator());
|
|
assertTrue(cpu.getNegativeFlag());
|
|
assertFalse(cpu.getOverflowFlag());
|
|
assertFalse(cpu.getZeroFlag());
|
|
assertTrue(cpu.getCarryFlag());
|
|
|
|
cpu.reset();
|
|
bus.loadProgram(0xa9, 0x02, // LDA #$02
|
|
0xfd, 0x10, 0xab); // SBC $ab10,X
|
|
cpu.setXRegister(0x30);
|
|
cpu.step(2);
|
|
assertEquals(0x00, cpu.getAccumulator());
|
|
assertFalse(cpu.getNegativeFlag());
|
|
assertFalse(cpu.getOverflowFlag());
|
|
assertTrue(cpu.getZeroFlag());
|
|
assertTrue(cpu.getCarryFlag());
|
|
}
|
|
|
|
public void test_SBC_IncludesNotOfCarry() throws MemoryAccessException {
|
|
bus.write(0xab40, 0x01);
|
|
|
|
// Subtrace with Carry Flag cleared
|
|
bus.loadProgram(0x18, // CLC
|
|
0xa9, 0x05, // LDA #$00
|
|
0xfd, 0x10, 0xab); // SBC $ab10,X
|
|
cpu.setXRegister(0x30);
|
|
cpu.step(3);
|
|
assertEquals(0x03, cpu.getAccumulator());
|
|
|
|
cpu.reset();
|
|
|
|
// Subtrace with Carry Flag cleared
|
|
bus.loadProgram(0x18, // CLC
|
|
0xa9, 0x00, // LDA #$00
|
|
0xfd, 0x10, 0xab); // SBC $ab10,X
|
|
cpu.setXRegister(0x30);
|
|
cpu.step(3);
|
|
assertEquals(0xfe, cpu.getAccumulator());
|
|
|
|
cpu.reset();
|
|
|
|
// Subtract with Carry Flag set
|
|
bus.loadProgram(0x38, // SEC
|
|
0xa9, 0x05, // LDA #$00
|
|
0xfd, 0x10, 0xab); // SBC $ab10,X
|
|
cpu.setXRegister(0x30);
|
|
cpu.step(3);
|
|
assertEquals(0x04, cpu.getAccumulator());
|
|
assertTrue(cpu.getCarryFlag());
|
|
|
|
cpu.reset();
|
|
|
|
// Subtract with Carry Flag set
|
|
bus.loadProgram(0x38, // SEC
|
|
0xa9, 0x00, // LDA #$00
|
|
0xfd, 0x10, 0xab); // SBC $ab10,X
|
|
cpu.setXRegister(0x30);
|
|
cpu.step(3);
|
|
assertEquals(0xff, cpu.getAccumulator());
|
|
assertFalse(cpu.getCarryFlag());
|
|
|
|
}
|
|
|
|
public void test_SBC_DecimalMode() throws MemoryAccessException {
|
|
bus.write(0xab40, 0x01);
|
|
bus.write(0xab50, 0x11);
|
|
|
|
bus.loadProgram(0xf8, // SED
|
|
0xa9, 0x00, // LDA #$00
|
|
0xfd, 0x10, 0xab); // SBC $ab10,X
|
|
cpu.setXRegister(0x30);
|
|
cpu.step(3);
|
|
assertEquals(0x98, cpu.getAccumulator());
|
|
assertFalse(cpu.getCarryFlag()); // borrow = set flag
|
|
assertFalse(cpu.getNegativeFlag());
|
|
assertFalse(cpu.getOverflowFlag());
|
|
assertFalse(cpu.getZeroFlag());
|
|
assertTrue(cpu.getDecimalModeFlag());
|
|
|
|
cpu.reset();
|
|
|
|
bus.loadProgram(0xf8, // SED
|
|
0xa9, 0x99, // LDA #$99
|
|
0xfd, 0x10, 0xab); // SBC $ab10,X
|
|
cpu.setXRegister(0x30);
|
|
cpu.step(3);
|
|
assertEquals(0x97, cpu.getAccumulator());
|
|
assertTrue(cpu.getCarryFlag()); // No borrow = clear flag
|
|
assertFalse(cpu.getNegativeFlag());
|
|
assertFalse(cpu.getOverflowFlag());
|
|
assertFalse(cpu.getZeroFlag());
|
|
assertTrue(cpu.getDecimalModeFlag());
|
|
|
|
cpu.reset();
|
|
|
|
bus.loadProgram(0xf8, // SED
|
|
0xa9, 0x50, // LDA #$50
|
|
0xfd, 0x10, 0xab); // SBC $ab10,X
|
|
cpu.setXRegister(0x30);
|
|
cpu.step(3);
|
|
assertEquals(0x48, cpu.getAccumulator());
|
|
assertTrue(cpu.getCarryFlag());
|
|
assertFalse(cpu.getNegativeFlag());
|
|
assertFalse(cpu.getOverflowFlag());
|
|
assertFalse(cpu.getZeroFlag());
|
|
assertTrue(cpu.getDecimalModeFlag());
|
|
|
|
|
|
cpu.reset();
|
|
|
|
bus.loadProgram(0xf8, // SED
|
|
0xa9, 0x02, // LDA #$02
|
|
0xfd, 0x10, 0xab); // SBC $ab10,X
|
|
cpu.setXRegister(0x30);
|
|
cpu.step(3);
|
|
assertEquals(0x00, cpu.getAccumulator());
|
|
assertTrue(cpu.getCarryFlag());
|
|
assertFalse(cpu.getNegativeFlag());
|
|
assertFalse(cpu.getOverflowFlag());
|
|
assertTrue(cpu.getZeroFlag());
|
|
assertTrue(cpu.getDecimalModeFlag());
|
|
|
|
cpu.reset();
|
|
|
|
bus.loadProgram(0xf8, // SED
|
|
0xa9, 0x10, // LDA #$10
|
|
0xfd, 0x20, 0xab); // SBC $ab20,X
|
|
cpu.setXRegister(0x30);
|
|
cpu.step(3);
|
|
assertEquals(0x98, cpu.getAccumulator());
|
|
assertFalse(cpu.getCarryFlag());
|
|
assertFalse(cpu.getNegativeFlag());
|
|
assertFalse(cpu.getOverflowFlag());
|
|
assertFalse(cpu.getZeroFlag());
|
|
assertTrue(cpu.getDecimalModeFlag());
|
|
|
|
cpu.reset();
|
|
|
|
bus.loadProgram(0x38, // SEC
|
|
0xf8, // SED
|
|
0xa9, 0x05, // LDA #$05
|
|
0xfd, 0x10, 0xab); // SBC $ab10,X
|
|
cpu.setXRegister(0x30);
|
|
cpu.step(4);
|
|
assertEquals(0x04, cpu.getAccumulator());
|
|
assertTrue(cpu.getCarryFlag());
|
|
assertFalse(cpu.getNegativeFlag());
|
|
assertFalse(cpu.getOverflowFlag());
|
|
assertFalse(cpu.getZeroFlag());
|
|
assertTrue(cpu.getDecimalModeFlag());
|
|
|
|
cpu.reset();
|
|
|
|
bus.loadProgram(0x38, // SEC
|
|
0xf8, // SED
|
|
0xa9, 0x00, // LDA #$00
|
|
0xfd, 0x10, 0xab); // SBC $ab10,X
|
|
cpu.setXRegister(0x30);
|
|
cpu.step(4);
|
|
assertEquals(0x99, cpu.getAccumulator());
|
|
assertFalse(cpu.getCarryFlag());
|
|
assertFalse(cpu.getNegativeFlag());
|
|
assertFalse(cpu.getOverflowFlag());
|
|
assertFalse(cpu.getZeroFlag());
|
|
assertTrue(cpu.getDecimalModeFlag());
|
|
}
|
|
|
|
}
|