package com.loomcom.symon;
import com.loomcom.symon.devices.Memory;
import com.loomcom.symon.exceptions.MemoryAccessException;
import junit.framework.TestCase;
public class CpuIndirectModeTest extends TestCase {
protected Cpu cpu;
protected Bus bus;
protected Memory mem;
protected void setUp() throws Exception {
this.cpu = new Cpu();
this.bus = new Bus(0x0000, 0xffff);
this.mem = new Memory(0x0000, 0xffff);
bus.addCpu(cpu);
bus.addDevice(mem);
// Load the reset vector.
bus.write(0xfffc, Bus.DEFAULT_LOAD_ADDRESS & 0x00ff);
bus.write(0xfffd, (Bus.DEFAULT_LOAD_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());
}
/*
* The following opcodes are tested for correctness in this file:
*
* JMP - $6c
*
*/
/* JMP - Jump - $6c */
public void test_JMP_notOnPageBoundary() throws MemoryAccessException {
bus.write(0x3400, 0x00);
bus.write(0x3401, 0x54);
bus.loadProgram(0x6c, 0x00, 0x34);
cpu.step();
assertEquals(0x5400, cpu.getProgramCounter());
// No change to status flags.
assertEquals(0x20, cpu.getProcessorStatus());
}
public void test_JMP_with_ROR_Bug() throws MemoryAccessException {
cpu.setBehavior(Cpu.CpuBehavior.NMOS_WITH_ROR_BUG);
bus.write(0x3400, 0x22);
bus.write(0x34ff, 0x00);
bus.write(0x3500, 0x54);
bus.loadProgram(0x6c, 0xff, 0x34);
cpu.step();
assertEquals(0x2200, cpu.getProgramCounter());
// No change to status flags.
assertEquals(0x20, cpu.getProcessorStatus());
}
public void test_JMP_withIndirectBug() throws MemoryAccessException {
cpu.setBehavior(Cpu.CpuBehavior.NMOS_WITH_INDIRECT_JMP_BUG);
bus.write(0x3400, 0x22);
bus.write(0x34ff, 0x00);
bus.write(0x3500, 0x54);
bus.loadProgram(0x6c, 0xff, 0x34);
cpu.step();
assertEquals(0x2200, cpu.getProgramCounter());
// No change to status flags.
assertEquals(0x20, cpu.getProcessorStatus());
}
public void test_JMP_withOutIndirectBug() throws MemoryAccessException {
cpu.setBehavior(Cpu.CpuBehavior.NMOS_WITHOUT_INDIRECT_JMP_BUG);
bus.write(0x3400, 0x22);
bus.write(0x34ff, 0x00);
bus.write(0x3500, 0x54);
bus.loadProgram(0x6c, 0xff, 0x34);
cpu.step();
assertEquals(0x5400, cpu.getProgramCounter());
// No change to status flags.
assertEquals(0x20, cpu.getProcessorStatus());
}
public void test_JMP_cmos() throws MemoryAccessException {
cpu.setBehavior(Cpu.CpuBehavior.CMOS);
bus.write(0x3400, 0x22);
bus.write(0x34ff, 0x00);
bus.write(0x3500, 0x54);
bus.loadProgram(0x6c, 0xff, 0x34);
cpu.step();
assertEquals(0x5400, cpu.getProgramCounter());
// No change to status flags.
assertEquals(0x20, cpu.getProcessorStatus());
}
}