package com.loomcom.symon;
import com.loomcom.symon.devices.Memory;
import org.junit.*;
import static org.junit.Assert.*;
public class CpuIndexedIndirectModeTest {
protected Cpu cpu;
protected Bus bus;
protected Memory mem;
@Before
public void runBeforeEveryTest() 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());
}
@Test
public void test_LDA() throws Exception {
bus.write(0x008c, 0x3f);
bus.write(0x008d, 0xc4);
bus.write(0xc43f, 0x45);
cpu.setXRegister(0x0c);
bus.loadProgram(0xa1, 0x80); // LDA ($80,X)
cpu.step(1);
assertEquals(0x45, cpu.getAccumulator());
}
@Test
public void testZeroPageWrap() throws Exception {
bus.write(0x0020, 0x01);
bus.write(0x0021, 0x07); // ($0701)
bus.write(0x0701, 0xaa);
bus.write(0x000f, 0x02);
bus.write(0x0010, 0x08); // ($0802)
bus.write(0x0802, 0xbb);
bus.write(0x010f, 0x03);
bus.write(0x0110, 0x09); // ($0903)
bus.write(0x0903, 0xcc);
cpu.setXRegister(0x10);
// No wrap needed
bus.loadProgram(0xa1, 0x10, // LDA ($10,X) = ($10 + $10) & $ff = $20
0xa1, 0xff); // LDA ($ff,X) = ($ff + $10) & $ff = $0f, NOT $10f!
cpu.step(1);
assertEquals(0xaa, cpu.getAccumulator());
cpu.step(1);
assertEquals(0xbb, cpu.getAccumulator());
}
@Test
public void test_ORA() throws Exception {
bus.write(0x0012, 0x1f);
bus.write(0x0013, 0xc5);
bus.write(0xc51f, 0x31);
cpu.setXRegister(0x02);
cpu.setAccumulator(0x15);
bus.loadProgram(0x01, 0x10); // ORA ($10,X)
cpu.step(1);
assertEquals(0x35, cpu.getAccumulator());
assertEquals(0x31, bus.read(0xc51f));
}
@Test
public void test_AND() throws Exception {
bus.write(0x0012, 0x1f);
bus.write(0x0013, 0xc5);
bus.write(0xc51f, 0x31);
cpu.setXRegister(0x02);
cpu.setAccumulator(0x15);
bus.loadProgram(0x21, 0x10); // AND ($10,X)
cpu.step(1);
assertEquals(0x11, cpu.getAccumulator());
assertEquals(0x31, bus.read(0xc51f));
}
}