Renamed project to "Symon".
This commit is contained in:
Seth Morabito committed
1 parent
9a6a256073
commit
3f74489757
20 files changed
+102
-42
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@@ -0,0 +1,132 @@
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package com.loomcom.symon;
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import java.util.*;
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import com.loomcom.symon.devices.*;
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import com.loomcom.symon.exceptions.*;
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/**
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* The Bus ties the whole thing together, man.
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*/
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public class Bus {
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// By default, our bus starts at 0, and goes up to 64K
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private int startAddress = 0x0000;
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private int endAddress = 0xffff;
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// The CPU
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private Cpu cpu;
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// Ordered list of IO devices.
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private SortedSet<Device> devices;
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public Bus(int size) {
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this(0, size - 1);
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}
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public Bus(int startAddress, int endAddress) {
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this.devices = new TreeSet<Device>();
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this.startAddress = startAddress;
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this.endAddress = endAddress;
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}
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public int startAddress() {
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return startAddress;
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}
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public int endAddress() {
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return endAddress;
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}
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public void addDevice(Device device)
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throws MemoryRangeException {
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// Make sure there's no memory overlap.
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MemoryRange memRange = device.getMemoryRange();
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for (Device d : devices) {
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if (d.getMemoryRange().overlaps(memRange)) {
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throw new MemoryRangeException("The device being added " +
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"overlaps with an existing " +
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"device.");
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}
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}
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// Add the device
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device.setBus(this);
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devices.add(device);
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}
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public void addCpu(Cpu cpu) {
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cpu.setBus(this);
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this.cpu = cpu;
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}
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/**
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* Returns true if the memory map is full, i.e., there are no
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* gaps between any IO devices. All memory locations map to some
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* device.
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*/
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public boolean isComplete() {
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// Emtpy maps cannot be complete.
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if (devices.isEmpty()) { return false; }
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// Loop over devices and ensure they are contiguous.
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MemoryRange prev = null;
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int i = 0;
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int length = devices.size();
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for (Device d : devices) {
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MemoryRange cur = d.getMemoryRange();
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if (i == 0) {
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// If the first entry doesn't start at 'startAddress', return false.
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if (cur.startAddress() != startAddress) { return false; }
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}
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if (prev != null && i < length - 1) {
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// Otherwise, compare previous map's end against this map's
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// endAddress. They must be adjacent!
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if (cur.startAddress() - 1 != prev.endAddress()) {
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return false;
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}
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}
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if (i == length - 1) {
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// If the last entry doesn't end at endAddress, return false;
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if (cur.endAddress() != endAddress) { return false; }
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}
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i++;
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prev = cur;
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}
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// Must be complete.
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return true;
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}
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public int read(int address) {
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for (Device d : devices) {
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MemoryRange range = d.getMemoryRange();
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if (range.includes(address)) {
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// Compute offset into this device's address space.
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int devAddr = address - range.startAddress();
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return d.read(devAddr);
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}
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}
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// TODO: Raise access error.
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throw new RuntimeException("Read failed! Device not found.");
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}
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public void write(int address, int value) {
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for (Device d : devices) {
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MemoryRange range = d.getMemoryRange();
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if (range.includes(address)) {
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// Compute offset into this device's address space.
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int devAddr = address - range.startAddress();
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d.write(devAddr, value);
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return;
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}
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}
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// TODO: Raise access error.
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throw new RuntimeException("Write failed! Device not found.");
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}
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public SortedSet<Device> getDevices() {
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// Expose a copy of the device list, not the original
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return new TreeSet<Device>(devices);
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}
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}
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@@ -0,0 +1,72 @@
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package com.loomcom.symon;
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import java.io.*;
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public class CommandParser {
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private BufferedReader in;
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private BufferedWriter out;
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private Simulator simulator;
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public CommandParser(InputStream i, OutputStream o, Simulator s) {
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this.in = new BufferedReader(new InputStreamReader(i));
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this.out = new BufferedWriter(new OutputStreamWriter(o));
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this.simulator = s;
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}
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public void run() {
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try {
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String command = null;
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greeting();
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prompt();
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while (!shouldQuit(command = readLine())) {
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dispatch(command);
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prompt();
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}
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writeLine("\n\nGoodbye!");
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} catch (IOException ex) {
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System.err.println("Error: " + ex.toString());
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System.exit(1);
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}
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}
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/**
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* Dispatch the command.
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*/
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public void dispatch(String command) throws IOException {
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writeLine("You entered: " + command);
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}
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/*******************************************************************
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* Private
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*******************************************************************/
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private void greeting() throws IOException {
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writeLine("Welcome to the j6502 Simulator!");
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}
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private void prompt() throws IOException {
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out.write("j6502> ");
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out.flush();
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}
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private String readLine() throws IOException {
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String line = in.readLine();
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if (line == null) { return null; }
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return line.trim();
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}
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private void writeLine(String line) throws IOException {
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out.write(line);
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out.newLine();
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out.flush();
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}
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/**
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* Returns true if the line is a quit.
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*/
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private boolean shouldQuit(String line) {
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return (line == null || "q".equals(line.toLowerCase()));
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}
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}
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@@ -0,0 +1,837 @@
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package com.loomcom.symon;
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import java.util.Arrays;
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/**
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* Main 6502 CPU Simulation.
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*/
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public class Cpu implements InstructionTable {
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/* The Bus */
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private Bus bus;
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/* User Registers */
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private int a; // Accumulator
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private int x; // X index register
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private int y; // Y index register
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/* Internal Registers */
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private int pc; // Program Counter register
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private int sp; // Stack Pointer register
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private int ir; // Instruction register
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/* Operands for the current instruction */
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private int[] operands = new int[2];
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private int addr; // The address the most recent instruction
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// was fetched from
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/* Status Flag Register bits */
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private boolean carryFlag;
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private boolean negativeFlag;
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private boolean zeroFlag;
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private boolean irqDisableFlag;
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private boolean decimalModeFlag;
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private boolean breakFlag;
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private boolean overflowFlag;
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// Note: Zero Flag and Negative Flag are read directly from Accumulator.
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/**
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* Construct a new CPU.
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*/
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public Cpu() {}
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/**
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* Set the bus reference for this CPU.
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*/
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public void setBus(Bus bus) {
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this.bus = bus;
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}
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/**
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* Return the Bus that this CPU is associated with.
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*/
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public Bus getBus() {
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return bus;
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}
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/**
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* Reset the CPU to known initial values.
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*/
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public void reset() {
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// Registers
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sp = 0x01ff;
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// Set the PC to the address stored in 0xfffc
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pc = CpuUtils.address(bus.read(0xfffc), bus.read(0xfffd));
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// Clear instruction register.
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ir = 0;
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// Clear status register bits.
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carryFlag = false;
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irqDisableFlag = false;
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decimalModeFlag = false;
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breakFlag = false;
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overflowFlag = false;
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}
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/**
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* Performs an individual machine cycle.
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*/
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public void step() {
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// Store the address from which the IR was read, for debugging
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addr = pc;
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// Fetch memory location for this instruction.
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ir = bus.read(pc);
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// TODO: The way we increment the PC may need
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// to change when interrupts are implemented
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// Increment PC
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incProgramCounter();
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// Decode the instruction and operands
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int size = Cpu.instructionSizes[ir];
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for (int i = 0; i < size-1; i++) {
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operands[i] = bus.read(pc);
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// Increment PC after reading
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incProgramCounter();
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}
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// Execute
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switch(ir) {
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case 0x00: // HLT
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// TODO: Halt!
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break;
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case 0x01: // n/a
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break;
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case 0x02: // n/a
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break;
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case 0x03: // n/a
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break;
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case 0x04: // n/a
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break;
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case 0x05: // n/a
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break;
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case 0x06: // n/a
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break;
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case 0x07: // n/a
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break;
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case 0x08: // n/a
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break;
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case 0x09: // n/a
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break;
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case 0x0a: // n/a
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break;
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case 0x0b: // n/a
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break;
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case 0x0c: // n/a
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break;
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case 0x0d: // n/a
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break;
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case 0x0e: // n/a
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break;
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case 0x0f: // n/a
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break;
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case 0x10: // n/a
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break;
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case 0x11: // n/a
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break;
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case 0x12: // n/a
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break;
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case 0x13: // n/a
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break;
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case 0x14: // n/a
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break;
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case 0x15: // n/a
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break;
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case 0x16: // n/a
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break;
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case 0x17: // n/a
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break;
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case 0x18: // n/a
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break;
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case 0x19: // n/a
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break;
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case 0x1a: // n/a
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break;
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case 0x1b: // n/a
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break;
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case 0x1c: // n/a
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break;
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case 0x1d: // n/a
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break;
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case 0x1e: // n/a
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break;
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case 0x1f: // n/a
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break;
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case 0x20: // n/a
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break;
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case 0x21: // n/a
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break;
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case 0x22: // n/a
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break;
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case 0x23: // n/a
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break;
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case 0x24: // n/a
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break;
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case 0x25: // n/a
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break;
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case 0x26: // n/a
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break;
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case 0x27: // n/a
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break;
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case 0x28: // n/a
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break;
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case 0x29: // n/a
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break;
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case 0x2a: // n/a
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break;
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case 0x2b: // n/a
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break;
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case 0x2c: // n/a
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break;
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case 0x2d: // n/a
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break;
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case 0x2e: // n/a
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break;
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case 0x2f: // n/a
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break;
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case 0x30: // n/a
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break;
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case 0x31: // n/a
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break;
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case 0x32: // n/a
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break;
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case 0x33: // n/a
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break;
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case 0x34: // n/a
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break;
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case 0x35: // n/a
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break;
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case 0x36: // n/a
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break;
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case 0x37: // n/a
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break;
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case 0x38: // n/a
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break;
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case 0x39: // n/a
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break;
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case 0x3a: // n/a
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break;
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case 0x3b: // n/a
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break;
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case 0x3c: // n/a
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break;
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case 0x3d: // n/a
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break;
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case 0x3e: // n/a
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break;
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case 0x3f: // n/a
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break;
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case 0x40: // n/a
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break;
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case 0x41: // n/a
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break;
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case 0x42: // n/a
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break;
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case 0x43: // n/a
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break;
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case 0x44: // n/a
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break;
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case 0x45: // n/a
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break;
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case 0x46: // n/a
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||||
break;
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case 0x47: // n/a
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||||
break;
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||||
case 0x48: // n/a
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||||
break;
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||||
case 0x49: // n/a
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break;
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case 0x4a: // n/a
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break;
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case 0x4b: // n/a
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break;
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case 0x4c: // JMP - Absolute
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pc = CpuUtils.address(operands[0], operands[1]);
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break;
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case 0x4d: // n/a
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break;
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case 0x4e: // n/a
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break;
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case 0x4f: // n/a
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||||
break;
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||||
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||||
case 0x50: // n/a
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||||
break;
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||||
case 0x51: // n/a
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||||
break;
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||||
case 0x52: // n/a
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||||
break;
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||||
case 0x53: // n/a
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||||
break;
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||||
case 0x54: // n/a
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||||
break;
|
||||
case 0x55: // n/a
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||||
break;
|
||||
case 0x56: // n/a
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||||
break;
|
||||
case 0x57: // n/a
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||||
break;
|
||||
case 0x58: // n/a
|
||||
break;
|
||||
case 0x59: // n/a
|
||||
break;
|
||||
case 0x5a: // n/a
|
||||
break;
|
||||
case 0x5b: // n/a
|
||||
break;
|
||||
case 0x5c: // n/a
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||||
break;
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||||
case 0x5d: // n/a
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||||
break;
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||||
case 0x5e: // n/a
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||||
break;
|
||||
case 0x5f: // n/a
|
||||
break;
|
||||
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||||
case 0x60: // n/a
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||||
break;
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||||
case 0x61: // n/a
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||||
break;
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||||
case 0x62: // n/a
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||||
break;
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||||
case 0x63: // n/a
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||||
break;
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||||
case 0x64: // n/a
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||||
break;
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||||
case 0x65: // n/a
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||||
break;
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||||
case 0x66: // n/a
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||||
break;
|
||||
case 0x67: // n/a
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||||
break;
|
||||
case 0x68: // n/a
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||||
break;
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||||
case 0x69: // n/a
|
||||
break;
|
||||
case 0x6a: // n/a
|
||||
break;
|
||||
case 0x6b: // n/a
|
||||
break;
|
||||
case 0x6c: // n/a
|
||||
break;
|
||||
case 0x6d: // n/a
|
||||
break;
|
||||
case 0x6e: // n/a
|
||||
break;
|
||||
case 0x6f: // n/a
|
||||
break;
|
||||
|
||||
case 0x70: // n/a
|
||||
break;
|
||||
case 0x71: // n/a
|
||||
break;
|
||||
case 0x72: // n/a
|
||||
break;
|
||||
case 0x73: // n/a
|
||||
break;
|
||||
case 0x74: // n/a
|
||||
break;
|
||||
case 0x75: // n/a
|
||||
break;
|
||||
case 0x76: // n/a
|
||||
break;
|
||||
case 0x77: // n/a
|
||||
break;
|
||||
case 0x78: // n/a
|
||||
break;
|
||||
case 0x79: // n/a
|
||||
break;
|
||||
case 0x7a: // n/a
|
||||
break;
|
||||
case 0x7b: // n/a
|
||||
break;
|
||||
case 0x7c: // n/a
|
||||
break;
|
||||
case 0x7d: // n/a
|
||||
break;
|
||||
case 0x7e: // n/a
|
||||
break;
|
||||
case 0x7f: // n/a
|
||||
break;
|
||||
|
||||
case 0x80: // n/a
|
||||
break;
|
||||
case 0x81: // n/a
|
||||
break;
|
||||
case 0x82: // n/a
|
||||
break;
|
||||
case 0x83: // n/a
|
||||
break;
|
||||
case 0x84: // n/a
|
||||
break;
|
||||
case 0x85: // n/a
|
||||
break;
|
||||
case 0x86: // n/a
|
||||
break;
|
||||
case 0x87: // n/a
|
||||
break;
|
||||
case 0x88: // n/a
|
||||
break;
|
||||
case 0x89: // n/a
|
||||
break;
|
||||
case 0x8a: // n/a
|
||||
break;
|
||||
case 0x8b: // n/a
|
||||
break;
|
||||
case 0x8c: // n/a
|
||||
break;
|
||||
case 0x8d: // n/a
|
||||
break;
|
||||
case 0x8e: // n/a
|
||||
break;
|
||||
case 0x8f: // n/a
|
||||
break;
|
||||
|
||||
case 0x90: // n/a
|
||||
break;
|
||||
case 0x91: // n/a
|
||||
break;
|
||||
case 0x92: // n/a
|
||||
break;
|
||||
case 0x93: // n/a
|
||||
break;
|
||||
case 0x94: // n/a
|
||||
break;
|
||||
case 0x95: // n/a
|
||||
break;
|
||||
case 0x96: // n/a
|
||||
break;
|
||||
case 0x97: // n/a
|
||||
break;
|
||||
case 0x98: // n/a
|
||||
break;
|
||||
case 0x99: // n/a
|
||||
break;
|
||||
case 0x9a: // n/a
|
||||
break;
|
||||
case 0x9b: // n/a
|
||||
break;
|
||||
case 0x9c: // n/a
|
||||
break;
|
||||
case 0x9d: // n/a
|
||||
break;
|
||||
case 0x9e: // n/a
|
||||
break;
|
||||
case 0x9f: // n/a
|
||||
break;
|
||||
|
||||
case 0xa0: // LDY - Immediate
|
||||
y = operands[0];
|
||||
setZeroFlag(y);
|
||||
setNegativeFlag(y);
|
||||
break;
|
||||
case 0xa1: // n/a
|
||||
break;
|
||||
case 0xa2: // LDX - Immediate
|
||||
x = operands[0];
|
||||
setZeroFlag(x);
|
||||
setNegativeFlag(x);
|
||||
break;
|
||||
case 0xa3: // n/a
|
||||
break;
|
||||
case 0xa4: // n/a
|
||||
break;
|
||||
case 0xa5: // n/a
|
||||
break;
|
||||
case 0xa6: // n/a
|
||||
break;
|
||||
case 0xa7: // n/a
|
||||
break;
|
||||
case 0xa8: // n/a
|
||||
break;
|
||||
case 0xa9: // LDA - Immediate
|
||||
a = operands[0];
|
||||
setZeroFlag(a);
|
||||
setNegativeFlag(a);
|
||||
break;
|
||||
case 0xaa: // n/a
|
||||
break;
|
||||
case 0xab: // n/a
|
||||
break;
|
||||
case 0xac: // n/a
|
||||
break;
|
||||
case 0xad: // n/a
|
||||
break;
|
||||
case 0xae: // n/a
|
||||
break;
|
||||
case 0xaf: // n/a
|
||||
break;
|
||||
|
||||
case 0xb0: // n/a
|
||||
break;
|
||||
case 0xb1: // n/a
|
||||
break;
|
||||
case 0xb2: // n/a
|
||||
break;
|
||||
case 0xb3: // n/a
|
||||
break;
|
||||
case 0xb4: // n/a
|
||||
break;
|
||||
case 0xb5: // n/a
|
||||
break;
|
||||
case 0xb6: // n/a
|
||||
break;
|
||||
case 0xb7: // n/a
|
||||
break;
|
||||
case 0xb8: // n/a
|
||||
break;
|
||||
case 0xb9: // n/a
|
||||
break;
|
||||
case 0xba: // n/a
|
||||
break;
|
||||
case 0xbb: // n/a
|
||||
break;
|
||||
case 0xbc: // n/a
|
||||
break;
|
||||
case 0xbd: // n/a
|
||||
break;
|
||||
case 0xbe: // n/a
|
||||
break;
|
||||
case 0xbf: // n/a
|
||||
break;
|
||||
|
||||
case 0xc0: // n/a
|
||||
break;
|
||||
case 0xc1: // n/a
|
||||
break;
|
||||
case 0xc2: // n/a
|
||||
break;
|
||||
case 0xc3: // n/a
|
||||
break;
|
||||
case 0xc4: // n/a
|
||||
break;
|
||||
case 0xc5: // n/a
|
||||
break;
|
||||
case 0xc6: // n/a
|
||||
break;
|
||||
case 0xc7: // n/a
|
||||
break;
|
||||
case 0xc8: // n/a
|
||||
break;
|
||||
case 0xc9: // n/a
|
||||
break;
|
||||
case 0xca: // n/a
|
||||
break;
|
||||
case 0xcb: // n/a
|
||||
break;
|
||||
case 0xcc: // n/a
|
||||
break;
|
||||
case 0xcd: // n/a
|
||||
break;
|
||||
case 0xce: // n/a
|
||||
break;
|
||||
case 0xcf: // n/a
|
||||
break;
|
||||
|
||||
case 0xd0: // n/a
|
||||
break;
|
||||
case 0xd1: // n/a
|
||||
break;
|
||||
case 0xd2: // n/a
|
||||
break;
|
||||
case 0xd3: // n/a
|
||||
break;
|
||||
case 0xd4: // n/a
|
||||
break;
|
||||
case 0xd5: // n/a
|
||||
break;
|
||||
case 0xd6: // n/a
|
||||
break;
|
||||
case 0xd7: // n/a
|
||||
break;
|
||||
case 0xd8: // n/a
|
||||
break;
|
||||
case 0xd9: // n/a
|
||||
break;
|
||||
case 0xda: // n/a
|
||||
break;
|
||||
case 0xdb: // n/a
|
||||
break;
|
||||
case 0xdc: // n/a
|
||||
break;
|
||||
case 0xdd: // n/a
|
||||
break;
|
||||
case 0xde: // n/a
|
||||
break;
|
||||
case 0xdf: // n/a
|
||||
break;
|
||||
|
||||
case 0xe0: // n/a
|
||||
break;
|
||||
case 0xe1: // n/a
|
||||
break;
|
||||
case 0xe2: // n/a
|
||||
break;
|
||||
case 0xe3: // n/a
|
||||
break;
|
||||
case 0xe4: // n/a
|
||||
break;
|
||||
case 0xe5: // n/a
|
||||
break;
|
||||
case 0xe6: // n/a
|
||||
break;
|
||||
case 0xe7: // n/a
|
||||
break;
|
||||
case 0xe8: // n/a
|
||||
break;
|
||||
case 0xe9: // n/a
|
||||
break;
|
||||
case 0xea: // NOP
|
||||
break;
|
||||
case 0xeb: // n/a
|
||||
break;
|
||||
case 0xec: // n/a
|
||||
break;
|
||||
case 0xed: // n/a
|
||||
break;
|
||||
case 0xee: // n/a
|
||||
break;
|
||||
case 0xef: // n/a
|
||||
break;
|
||||
|
||||
case 0xf0: // n/a
|
||||
break;
|
||||
case 0xf1: // n/a
|
||||
break;
|
||||
case 0xf2: // n/a
|
||||
break;
|
||||
case 0xf3: // n/a
|
||||
break;
|
||||
case 0xf4: // n/a
|
||||
break;
|
||||
case 0xf5: // n/a
|
||||
break;
|
||||
case 0xf6: // n/a
|
||||
break;
|
||||
case 0xf7: // n/a
|
||||
break;
|
||||
case 0xf8: // n/a
|
||||
break;
|
||||
case 0xf9: // n/a
|
||||
break;
|
||||
case 0xfa: // n/a
|
||||
break;
|
||||
case 0xfb: // n/a
|
||||
break;
|
||||
case 0xfc: // n/a
|
||||
break;
|
||||
case 0xfd: // n/a
|
||||
break;
|
||||
case 0xfe: // n/a
|
||||
break;
|
||||
case 0xff: // n/a
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* @return the negative flag
|
||||
*/
|
||||
public boolean getNegativeFlag() {
|
||||
return negativeFlag;
|
||||
}
|
||||
|
||||
/**
|
||||
* @param register the register value to test for negativity
|
||||
*/
|
||||
public void setNegativeFlag(int register) {
|
||||
this.negativeFlag = (((register>>>7)&0xff) == 1);
|
||||
}
|
||||
|
||||
/**
|
||||
* @param negativeFlag the negative flag to set
|
||||
*/
|
||||
public void setNegativeFlag(boolean negativeFlag) {
|
||||
this.negativeFlag = negativeFlag;
|
||||
}
|
||||
|
||||
/**
|
||||
* @return the carry flag
|
||||
*/
|
||||
public boolean getCarryFlag() {
|
||||
return carryFlag;
|
||||
}
|
||||
|
||||
/**
|
||||
* @param carryFlag the carry flag to set
|
||||
*/
|
||||
public void setCarryFlag(boolean carryFlag) {
|
||||
this.carryFlag = carryFlag;
|
||||
}
|
||||
|
||||
/**
|
||||
* @return the zero flag
|
||||
*/
|
||||
public boolean getZeroFlag() {
|
||||
return zeroFlag;
|
||||
}
|
||||
|
||||
/**
|
||||
* @param register the register to test for zero
|
||||
*/
|
||||
public void setZeroFlag(int register) {
|
||||
this.zeroFlag = (register == 0);
|
||||
}
|
||||
|
||||
/**
|
||||
* @param zeroFlag the zero flag to set
|
||||
*/
|
||||
public void setZeroFlag(boolean zeroFlag) {
|
||||
this.zeroFlag = zeroFlag;
|
||||
}
|
||||
|
||||
/**
|
||||
* @return the irq disable flag
|
||||
*/
|
||||
public boolean getIrqDisableFlag() {
|
||||
return irqDisableFlag;
|
||||
}
|
||||
|
||||
/**
|
||||
* @param irqDisableFlag the irq disable flag to set
|
||||
*/
|
||||
public void setIrqDisableFlag(boolean irqDisableFlag) {
|
||||
this.irqDisableFlag = irqDisableFlag;
|
||||
}
|
||||
|
||||
/**
|
||||
* @return the decimal mode flag
|
||||
*/
|
||||
public boolean getDecimalModeFlag() {
|
||||
return decimalModeFlag;
|
||||
}
|
||||
|
||||
/**
|
||||
* @param decimalModeFlag the decimal mde flag to set
|
||||
*/
|
||||
public void setDecimalModeFlag(boolean decimalModeFlag) {
|
||||
this.decimalModeFlag = decimalModeFlag;
|
||||
}
|
||||
|
||||
/**
|
||||
* @return the break flag
|
||||
*/
|
||||
public boolean getBreakFlag() {
|
||||
return breakFlag;
|
||||
}
|
||||
|
||||
/**
|
||||
* @param breakFlag the break flag to set
|
||||
*/
|
||||
public void setBreakFlag(boolean breakFlag) {
|
||||
this.breakFlag = breakFlag;
|
||||
}
|
||||
|
||||
/**
|
||||
* @return the overflow flag
|
||||
*/
|
||||
public boolean getOverflowFlag() {
|
||||
return overflowFlag;
|
||||
}
|
||||
|
||||
/**
|
||||
* @param overflowFlag the overflow flag to set
|
||||
*/
|
||||
public void setOverflowFlag(boolean overflowFlag) {
|
||||
this.overflowFlag = overflowFlag;
|
||||
}
|
||||
|
||||
public int getAccumulator() {
|
||||
return a;
|
||||
}
|
||||
|
||||
public int getXRegister() {
|
||||
return x;
|
||||
}
|
||||
|
||||
public int getYRegister() {
|
||||
return y;
|
||||
}
|
||||
|
||||
public int getProgramCounter() {
|
||||
return pc;
|
||||
}
|
||||
|
||||
/**
|
||||
* @return A string representing the current status register state.
|
||||
*/
|
||||
public String statusRegisterString() {
|
||||
StringBuffer sb = new StringBuffer();
|
||||
sb.append("(N:" + (getNegativeFlag() ? '1' : '0') + ", ");
|
||||
sb.append("V:" + (getOverflowFlag() ? '1' : '0') + ", ");
|
||||
sb.append("B:" + (getBreakFlag() ? '1' : '0') + ", ");
|
||||
sb.append("D:" + (getDecimalModeFlag() ? '1' : '0') + ", ");
|
||||
sb.append("I:" + (getIrqDisableFlag() ? '1' : '0') + ", ");
|
||||
sb.append("Z:" + (getZeroFlag() ? '1' : '0') + ", ");
|
||||
sb.append("C:" + (getCarryFlag() ? '1' : '0') + ")");
|
||||
return sb.toString();
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns a string representing the CPU state.
|
||||
*/
|
||||
public String toString() {
|
||||
String opcode = CpuUtils.opcode(ir, operands[0], operands[1]);
|
||||
StringBuffer sb = new StringBuffer(String.format("$%04X", addr) +
|
||||
" ");
|
||||
sb.append(String.format("%-14s", opcode));
|
||||
sb.append("A=" + String.format("$%02X", a) + " ");
|
||||
sb.append("X=" + String.format("$%02X", x) + " ");
|
||||
sb.append("Y=" + String.format("$%02X", y) + " ");
|
||||
sb.append("PC=" + String.format("$%04X", pc)+ " ");
|
||||
sb.append("P=" + statusRegisterString());
|
||||
return sb.toString();
|
||||
}
|
||||
|
||||
/**
|
||||
* Push an item onto the stack, and decrement the stack counter.
|
||||
* Silently fails to push onto the stack if SP is
|
||||
* TODO: Unit tests.
|
||||
*/
|
||||
protected void push(int data) {
|
||||
bus.write(sp, data);
|
||||
if (sp > 0x100) { sp--; }
|
||||
}
|
||||
|
||||
|
||||
/**
|
||||
* Pop a byte off the user stack, and increment the stack counter.
|
||||
* TODO: Unit tests.
|
||||
*/
|
||||
protected int pop() {
|
||||
int data = bus.read(sp);
|
||||
if (sp < 0x1ff) { sp++; }
|
||||
return data;
|
||||
}
|
||||
|
||||
/*
|
||||
* Increment the PC, rolling over if necessary.
|
||||
*/
|
||||
protected void incProgramCounter() {
|
||||
if (pc == 0xffff) {
|
||||
pc = 0;
|
||||
} else {
|
||||
++pc;
|
||||
}
|
||||
}
|
||||
|
||||
}
|
||||
@@ -0,0 +1,37 @@
|
||||
package com.loomcom.symon;
|
||||
|
||||
import com.loomcom.symon.InstructionTable.Mode;
|
||||
|
||||
public class CpuUtils {
|
||||
|
||||
/**
|
||||
* Given two bytes, return an address.
|
||||
*/
|
||||
public static int address(int lowByte, int hiByte) {
|
||||
return ((hiByte<<8)|lowByte);
|
||||
}
|
||||
|
||||
/**
|
||||
* Given an opcode and its operands, return a formatted name.
|
||||
*
|
||||
* @param opcode
|
||||
* @param operands
|
||||
* @return
|
||||
*/
|
||||
public static String opcode(int opcode, int op1, int op2) {
|
||||
String opcodeName = Cpu.opcodeNames[opcode];
|
||||
if (opcodeName == null) { return "???"; }
|
||||
|
||||
StringBuffer sb = new StringBuffer(opcodeName);
|
||||
|
||||
switch (Cpu.instructionModes[opcode]) {
|
||||
case ABS:
|
||||
sb.append(String.format(" $%04X", address(op1, op2)));
|
||||
break;
|
||||
case IMM:
|
||||
sb.append(String.format(" #$%02X", op1));
|
||||
}
|
||||
|
||||
return sb.toString();
|
||||
}
|
||||
}
|
||||
@@ -0,0 +1,249 @@
|
||||
package com.loomcom.symon;
|
||||
|
||||
public interface InstructionTable {
|
||||
|
||||
/**
|
||||
* Enumeration of Addressing Modes.
|
||||
*/
|
||||
public enum Mode {
|
||||
ACC {
|
||||
public String toString() {
|
||||
return "Accumulator";
|
||||
}
|
||||
},
|
||||
|
||||
ABS {
|
||||
public String toString() {
|
||||
return "Absolute";
|
||||
}
|
||||
},
|
||||
|
||||
ABX {
|
||||
public String toString() {
|
||||
return "Absolute, X-indexed";
|
||||
}
|
||||
},
|
||||
|
||||
ABY {
|
||||
public String toString() {
|
||||
return "Absolute, Y-indexed";
|
||||
}
|
||||
},
|
||||
|
||||
IMM {
|
||||
public String toString() {
|
||||
return "Immediate";
|
||||
}
|
||||
},
|
||||
|
||||
IMP {
|
||||
public String toString() {
|
||||
return "Implied";
|
||||
}
|
||||
},
|
||||
|
||||
IND {
|
||||
public String toString() {
|
||||
return "Indirect";
|
||||
}
|
||||
},
|
||||
|
||||
XIN {
|
||||
public String toString() {
|
||||
return "X-indexed Indirect";
|
||||
}
|
||||
},
|
||||
|
||||
INY {
|
||||
public String toString() {
|
||||
return "Indirect, Y-indexedY";
|
||||
}
|
||||
},
|
||||
|
||||
REL {
|
||||
public String toString() {
|
||||
return "Relative";
|
||||
}
|
||||
},
|
||||
|
||||
ZPG {
|
||||
public String toString() {
|
||||
return "Zeropage";
|
||||
}
|
||||
},
|
||||
|
||||
ZPX {
|
||||
public String toString() {
|
||||
return "Zeropage, X-indexed";
|
||||
}
|
||||
},
|
||||
|
||||
ZPY {
|
||||
public String toString() {
|
||||
return "Zeropage, Y-indexed";
|
||||
}
|
||||
},
|
||||
|
||||
NUL {
|
||||
public String toString() {
|
||||
return "NULL";
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// 6502 opcodes. No 65C02 opcodes implemented.
|
||||
|
||||
/**
|
||||
* Instruction opcode names.
|
||||
*/
|
||||
public static final String[] opcodeNames = {
|
||||
"BRK", "ORA", null, null, null, "ORA", "ASL", null,
|
||||
"PHP", "ORA", "ASL", null, null, "ORA", "ASL", null,
|
||||
"BPL", "ORA", null, null, null, "ORA", "ASL", null,
|
||||
"CLC", "ORA", null, null, null, "ORA", "ASL", null,
|
||||
"JSR", "AND", null, null, "BIT", "AND", "ROL", null,
|
||||
"PLP", "AND", "ROL", null, "BIT", "AND", "ROL", null,
|
||||
"BMI", "AND", null, null, null, "AND", "ROL", null,
|
||||
"SEC", "AND", null, null, null, "AND", "ROL", null,
|
||||
"RTI", "EOR", null, null, null, "EOR", "LSR", null,
|
||||
"PHA", "EOR", "LSR", null, "JMP", "EOR", "LSR", null,
|
||||
"BVC", "EOR", null, null, null, "EOR", "LSR", null,
|
||||
"CLI", "EOR", null, null, null, "EOR", "LSR", null,
|
||||
"RTS", "ADC", null, null, null, "ADC", "ROR", null,
|
||||
"PLA", "ADC", "ROR", null, "JMP", "ADC", "ROR", null,
|
||||
"BVS", "ADC", null, null, null, "ADC", "ROR", null,
|
||||
"SEI", "ADC", null, null, null, "ADC", "ROR", null,
|
||||
"BCS", "STA", null, null, "STY", "STA", "STX", null,
|
||||
"DEY", null, "TXA", null, "STY", "STA", "STX", null,
|
||||
"BCC", "STA", null, null, "STY", "STA", "STX", null,
|
||||
"TYA", "STA", "TXS", null, null, "STA", null, null,
|
||||
"LDY", "LDA", "LDX", null, "LDY", "LDA", "LDX", null,
|
||||
"TAY", "LDA", "TAX", null, "LDY", "LDA", "LDX", null,
|
||||
null, "LDA", null, null, "LDY", "LDA", "LDX", null,
|
||||
"CLV", "LDA", "TSX", null, "LDY", "LDA", "LDX", null,
|
||||
"CPY", "CMP", null, null, "CPY", "CMP", "DEC", null,
|
||||
"INY", "CMP", "DEX", null, "CPY", "CMP", "DEC", null,
|
||||
"BNE", "CMP", null, null, null, "CMP", "DEC", null,
|
||||
"CLD", "CMP", null, null, null, "CMP", "DEC", null,
|
||||
"CPX", "SBC", null, null, "CPX", "SBC", "INC", null,
|
||||
"INX", "SBC", "NOP", null, "CPX", "SBC", "INC", null,
|
||||
"BEQ", "SBC", null, null, null, "SBC", "INC", null,
|
||||
"SED", "SBC", null, null, null, "SBC", "INC", null
|
||||
};
|
||||
|
||||
/**
|
||||
* Instruction addressing modes.
|
||||
*/
|
||||
public static final Mode[] instructionModes = {
|
||||
Mode.IMP, Mode.XIN, Mode.NUL, Mode.NUL, // 0x00-0x03
|
||||
Mode.NUL, Mode.ZPG, Mode.ZPG, Mode.NUL, // 0x04-0x07
|
||||
Mode.IMP, Mode.IMM, Mode.ACC, Mode.NUL, // 0x08-0x0b
|
||||
Mode.NUL, Mode.ABS, Mode.ABS, Mode.NUL, // 0x0c-0x0f
|
||||
Mode.REL, Mode.INY, Mode.NUL, Mode.NUL, // 0x10-0x13
|
||||
Mode.NUL, Mode.ZPX, Mode.ZPX, Mode.NUL, // 0x14-0x17
|
||||
Mode.IMP, Mode.ABY, Mode.NUL, Mode.NUL, // 0x18-0x1b
|
||||
Mode.NUL, Mode.ABX, Mode.ABX, Mode.NUL, // 0x1c-0x1f
|
||||
Mode.ABS, Mode.XIN, Mode.NUL, Mode.NUL, // 0x20-0x23
|
||||
Mode.ZPG, Mode.ZPG, Mode.ZPG, Mode.NUL, // 0x24-0x27
|
||||
Mode.IMP, Mode.IMM, Mode.ACC, Mode.NUL, // 0x28-0x2b
|
||||
Mode.ABS, Mode.ABS, Mode.ABS, Mode.NUL, // 0x2c-0x2f
|
||||
Mode.REL, Mode.INY, Mode.NUL, Mode.NUL, // 0x30-0x33
|
||||
Mode.NUL, Mode.ZPX, Mode.ZPX, Mode.NUL, // 0x34-0x37
|
||||
Mode.IMP, Mode.ABY, Mode.NUL, Mode.NUL, // 0x38-0x3b
|
||||
Mode.NUL, Mode.ABX, Mode.ABX, Mode.NUL, // 0x3c-0x3f
|
||||
Mode.IMP, Mode.XIN, Mode.NUL, Mode.NUL, // 0x40-0x43
|
||||
Mode.NUL, Mode.ZPG, Mode.ZPG, Mode.NUL, // 0x44-0x47
|
||||
Mode.IMP, Mode.IMM, Mode.ACC, Mode.NUL, // 0x48-0x4b
|
||||
Mode.ABS, Mode.ABS, Mode.ABS, Mode.NUL, // 0x4c-0x4f
|
||||
Mode.REL, Mode.INY, Mode.NUL, Mode.NUL, // 0x50-0x53
|
||||
Mode.NUL, Mode.ZPX, Mode.ZPX, Mode.NUL, // 0x54-0x57
|
||||
Mode.IMP, Mode.ABY, Mode.NUL, Mode.NUL, // 0x58-0x5b
|
||||
Mode.NUL, Mode.ABX, Mode.ABX, Mode.NUL, // 0x5c-0x5f
|
||||
Mode.IMP, Mode.XIN, Mode.NUL, Mode.NUL, // 0x60-0x63
|
||||
Mode.NUL, Mode.ZPG, Mode.ZPG, Mode.NUL, // 0x64-0x67
|
||||
Mode.IMP, Mode.IMM, Mode.ACC, Mode.NUL, // 0x68-0x6b
|
||||
Mode.IND, Mode.ABS, Mode.ABS, Mode.NUL, // 0x6c-0x6f
|
||||
Mode.REL, Mode.INY, Mode.NUL, Mode.NUL, // 0x70-0x73
|
||||
Mode.NUL, Mode.ZPX, Mode.ZPX, Mode.NUL, // 0x74-0x77
|
||||
Mode.IMP, Mode.ABY, Mode.NUL, Mode.NUL, // 0x78-0x7b
|
||||
Mode.NUL, Mode.ABX, Mode.ABX, Mode.NUL, // 0x7c-0x7f
|
||||
Mode.REL, Mode.XIN, Mode.NUL, Mode.NUL, // 0x80-0x83
|
||||
Mode.ZPG, Mode.ZPG, Mode.ZPG, Mode.NUL, // 0x84-0x87
|
||||
Mode.IMP, Mode.NUL, Mode.IMP, Mode.NUL, // 0x88-0x8b
|
||||
Mode.ABS, Mode.ABS, Mode.ABS, Mode.NUL, // 0x8c-0x8f
|
||||
Mode.REL, Mode.INY, Mode.NUL, Mode.NUL, // 0x90-0x93
|
||||
Mode.ZPX, Mode.ZPX, Mode.ZPY, Mode.NUL, // 0x94-0x97
|
||||
Mode.IMP, Mode.ABX, Mode.IMP, Mode.NUL, // 0x98-0x9b
|
||||
Mode.NUL, Mode.ABY, Mode.NUL, Mode.NUL, // 0x9c-0x9f
|
||||
Mode.IMM, Mode.XIN, Mode.IMM, Mode.NUL, // 0xa0-0xa3
|
||||
Mode.ZPG, Mode.ZPG, Mode.ZPG, Mode.NUL, // 0xa4-0xa7
|
||||
Mode.IMP, Mode.IMM, Mode.IMP, Mode.NUL, // 0xa8-0xab
|
||||
Mode.ABS, Mode.ABS, Mode.ABS, Mode.NUL, // 0xac-0xaf
|
||||
Mode.NUL, Mode.INY, Mode.NUL, Mode.NUL, // 0xb0-0xb3
|
||||
Mode.ZPX, Mode.ZPX, Mode.ZPY, Mode.NUL, // 0xb4-0xb7
|
||||
Mode.IMP, Mode.ABX, Mode.IMP, Mode.NUL, // 0xb8-0xbb
|
||||
Mode.ABX, Mode.ABY, Mode.ABY, Mode.NUL, // 0xbc-0xbf
|
||||
Mode.IMM, Mode.XIN, Mode.NUL, Mode.NUL, // 0xc0-0xc3
|
||||
Mode.ZPG, Mode.ZPG, Mode.ZPG, Mode.NUL, // 0xc4-0xc7
|
||||
Mode.IMP, Mode.IMM, Mode.IMP, Mode.NUL, // 0xc8-0xcb
|
||||
Mode.ABS, Mode.ABS, Mode.ABS, Mode.NUL, // 0xcc-0xcf
|
||||
Mode.REL, Mode.INY, Mode.NUL, Mode.NUL, // 0xd0-0xd3
|
||||
Mode.NUL, Mode.ZPX, Mode.ZPX, Mode.NUL, // 0xd4-0xd7
|
||||
Mode.IMP, Mode.ABY, Mode.NUL, Mode.NUL, // 0xd8-0xdb
|
||||
Mode.NUL, Mode.ABX, Mode.ABX, Mode.NUL, // 0xdc-0xdf
|
||||
Mode.IMM, Mode.XIN, Mode.NUL, Mode.NUL, // 0xe0-0xe3
|
||||
Mode.ZPG, Mode.ZPG, Mode.ZPG, Mode.NUL, // 0xe4-0xe7
|
||||
Mode.IMP, Mode.IMM, Mode.IMP, Mode.NUL, // 0xe8-0xeb
|
||||
Mode.ABS, Mode.ABS, Mode.ABS, Mode.NUL, // 0xec-0xef
|
||||
Mode.REL, Mode.INY, Mode.NUL, Mode.NUL, // 0xf0-0xf3
|
||||
Mode.NUL, Mode.ZPX, Mode.ZPX, Mode.NUL, // 0xf4-0xf7
|
||||
Mode.IMP, Mode.ABY, Mode.NUL, Mode.NUL, // 0xf8-0xfb
|
||||
Mode.NUL, Mode.ABX, Mode.ABX, Mode.NUL // 0xfc-0xff
|
||||
};
|
||||
|
||||
|
||||
/**
|
||||
* Size, in bytes, required for each instruction.
|
||||
*/
|
||||
public static final int[] instructionSizes = {
|
||||
1, 2, 0, 0, 0, 2, 2, 0, 1, 2, 1, 0, 0, 3, 3, 0,
|
||||
2, 2, 0, 0, 0, 2, 2, 0, 1, 3, 0, 0, 0, 3, 3, 0,
|
||||
3, 2, 0, 0, 2, 2, 2, 0, 1, 2, 1, 0, 3, 3, 3, 0,
|
||||
2, 2, 0, 0, 0, 2, 2, 0, 1, 3, 0, 0, 0, 3, 3, 0,
|
||||
1, 2, 0, 0, 0, 2, 2, 0, 1, 2, 1, 0, 3, 3, 3, 0,
|
||||
2, 2, 0, 0, 0, 2, 2, 0, 1, 3, 0, 0, 0, 3, 3, 0,
|
||||
1, 2, 0, 0, 0, 2, 2, 0, 1, 2, 1, 0, 3, 3, 3, 0,
|
||||
2, 2, 0, 0, 0, 2, 2, 0, 1, 3, 0, 0, 0, 3, 3, 0,
|
||||
2, 2, 0, 0, 2, 2, 2, 0, 1, 0, 1, 0, 3, 3, 3, 0,
|
||||
2, 2, 0, 0, 2, 2, 2, 0, 1, 3, 1, 0, 0, 3, 0, 0,
|
||||
2, 2, 2, 0, 2, 2, 2, 0, 1, 2, 1, 0, 3, 3, 3, 0,
|
||||
0, 2, 0, 0, 2, 2, 2, 0, 1, 3, 1, 0, 3, 3, 3, 0,
|
||||
2, 2, 0, 0, 2, 2, 2, 0, 1, 2, 1, 0, 3, 3, 3, 0,
|
||||
2, 2, 0, 0, 0, 2, 2, 0, 1, 3, 0, 0, 0, 3, 3, 0,
|
||||
2, 2, 0, 0, 2, 2, 2, 0, 1, 2, 1, 0, 3, 3, 3, 0,
|
||||
2, 2, 0, 0, 0, 2, 2, 0, 1, 3, 0, 0, 0, 3, 3, 0
|
||||
};
|
||||
|
||||
/**
|
||||
* Number of clock cycles required for each instruction
|
||||
*/
|
||||
public static final int[] instructionClocks = {
|
||||
7, 6, 0, 0, 0, 3, 5, 0, 3, 2, 2, 0, 0, 4, 6, 0,
|
||||
2, 5, 0, 0, 0, 4, 6, 0, 2, 4, 0, 0, 0, 4, 7, 0,
|
||||
6, 6, 0, 0, 3, 3, 5, 0, 4, 2, 2, 0, 4, 4, 6, 0,
|
||||
2, 5, 0, 0, 0, 4, 6, 0, 2, 4, 0, 0, 0, 4, 7, 0,
|
||||
6, 6, 0, 0, 0, 3, 5, 0, 3, 2, 2, 0, 3, 4, 6, 0,
|
||||
2, 5, 0, 0, 0, 4, 6, 0, 2, 4, 0, 0, 0, 4, 7, 0,
|
||||
6, 6, 0, 0, 0, 3, 5, 0, 4, 2, 2, 0, 5, 4, 6, 0,
|
||||
2, 5, 0, 0, 0, 4, 6, 0, 2, 4, 0, 0, 0, 4, 7, 0,
|
||||
2, 6, 0, 0, 3, 3, 3, 0, 2, 0, 2, 0, 4, 4, 4, 0,
|
||||
2, 6, 0, 0, 4, 4, 4, 0, 2, 5, 2, 0, 0, 5, 0, 0,
|
||||
2, 6, 2, 0, 3, 3, 3, 0, 2, 2, 2, 0, 4, 4, 4, 0,
|
||||
0, 5, 0, 0, 4, 4, 4, 0, 2, 4, 2, 0, 4, 4, 4, 0,
|
||||
2, 6, 0, 0, 3, 3, 5, 0, 2, 2, 2, 0, 4, 4, 6, 0,
|
||||
2, 5, 0, 0, 0, 4, 6, 0, 2, 4, 0, 0, 0, 4, 7, 0,
|
||||
2, 6, 0, 0, 3, 3, 5, 0, 2, 2, 2, 0, 4, 4, 6, 0,
|
||||
2, 5, 0, 0, 0, 4, 6, 0, 2, 4, 0, 0, 0, 4, 7, 0
|
||||
};
|
||||
|
||||
}
|
||||
@@ -0,0 +1,87 @@
|
||||
package com.loomcom.symon;
|
||||
|
||||
import com.loomcom.symon.exceptions.*;
|
||||
|
||||
/**
|
||||
* MemoryRange is a simple container class representing a literal
|
||||
* range of memory, with a staraddress, and an end address. It has
|
||||
* guards against creating impossible memory ranges, and implements
|
||||
* some useful methods for checking address inclusion and range
|
||||
* overlaps.
|
||||
*/
|
||||
public class MemoryRange implements Comparable<MemoryRange> {
|
||||
|
||||
/** The starting address of the memory range. */
|
||||
public int startAddress;
|
||||
/** The ending address of the memory range. */
|
||||
public int endAddress;
|
||||
|
||||
public MemoryRange(int startAddress, int endAddress)
|
||||
throws MemoryRangeException {
|
||||
if (startAddress < 0 || endAddress < 0) {
|
||||
throw new MemoryRangeException("Addresses cannot be less than 0.");
|
||||
}
|
||||
if (startAddress >= endAddress) {
|
||||
throw new MemoryRangeException("End address must be greater " +
|
||||
"than start address.");
|
||||
}
|
||||
this.startAddress = startAddress;
|
||||
this.endAddress = endAddress;
|
||||
}
|
||||
|
||||
/**
|
||||
* @returns the starting address.
|
||||
*/
|
||||
public int startAddress() {
|
||||
return startAddress;
|
||||
}
|
||||
|
||||
/**
|
||||
* @returns the ending address.
|
||||
*/
|
||||
public int endAddress() {
|
||||
return endAddress;
|
||||
}
|
||||
|
||||
/**
|
||||
* Checks for address inclusion in the range.
|
||||
*
|
||||
* @returns true if the address is included within this range,
|
||||
* false otherwise.
|
||||
*/
|
||||
public boolean includes(int address) {
|
||||
return (address <= endAddress &&
|
||||
address >= startAddress);
|
||||
}
|
||||
|
||||
/**
|
||||
* Checks for overlapping memory ranges.
|
||||
*
|
||||
* @returns true if this range overlaps in any way with the other.
|
||||
*/
|
||||
public boolean overlaps(MemoryRange other) {
|
||||
return (this.includes(other.startAddress()) ||
|
||||
other.includes(this.startAddress()));
|
||||
}
|
||||
|
||||
// Implementation of Comparable interface
|
||||
public int compareTo(MemoryRange other) {
|
||||
if (other == null) {
|
||||
throw new NullPointerException("Cannot compare to null.");
|
||||
}
|
||||
if (this == other) {
|
||||
return 0;
|
||||
}
|
||||
Integer thisStartAddr = new Integer(this.startAddress());
|
||||
Integer thatStartAddr = new Integer(other.startAddress());
|
||||
return thisStartAddr.compareTo(thatStartAddr);
|
||||
}
|
||||
|
||||
public String toString() {
|
||||
StringBuffer desc = new StringBuffer("@");
|
||||
desc.append(String.format("0x%04x", startAddress));
|
||||
desc.append("-");
|
||||
desc.append(String.format("0x%04x", endAddress));
|
||||
return desc.toString();
|
||||
}
|
||||
}
|
||||
@@ -0,0 +1,160 @@
|
||||
/**
|
||||
* A simple profiler, for debugging the simulator.
|
||||
* It is safe to ignore me.
|
||||
*/
|
||||
|
||||
package com.loomcom.symon;
|
||||
|
||||
import com.loomcom.symon.devices.*;
|
||||
import com.loomcom.symon.exceptions.*;
|
||||
|
||||
public class Profiler implements InstructionTable {
|
||||
|
||||
|
||||
public static void main(String[] args) {
|
||||
// new Profiler().profileMemoryReads();
|
||||
// new Profiler().dumpOpCodes();
|
||||
new Profiler().profileProgram();
|
||||
}
|
||||
|
||||
public void dumpOpCodes() {
|
||||
for (int i = 0; i < 0x100; i++) {
|
||||
String name = opcodeNames[i];
|
||||
Mode mode = instructionModes[i];
|
||||
|
||||
System.out.print(String.format("0x%02x: ", i));
|
||||
|
||||
if (name == null) {
|
||||
System.out.println("n/a");
|
||||
} else {
|
||||
System.out.println(name + " (" + mode + ")");
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
public void profileProgram() {
|
||||
Bus bus = new Bus(0, 65535);
|
||||
Cpu cpu = new Cpu();
|
||||
|
||||
bus.addCpu(cpu);
|
||||
|
||||
try {
|
||||
bus.addDevice(new Memory(0x0000, 0x10000));
|
||||
} catch (MemoryRangeException ex) {
|
||||
System.err.println("Memory Range Exception! " + ex.getMessage());
|
||||
return;
|
||||
}
|
||||
|
||||
// Start at 0x0300
|
||||
bus.write(0xfffc, 0x00);
|
||||
bus.write(0xfffd, 0x03);
|
||||
|
||||
// The program to run, in an infinite loop.
|
||||
bus.write(0x0300, 0xa9); // LDA #$FF
|
||||
bus.write(0x0301, 0xff);
|
||||
bus.write(0x0302, 0xea); // NOP
|
||||
bus.write(0x0303, 0xea); // NOP
|
||||
bus.write(0x0304, 0xa0); // LDY #$1A
|
||||
bus.write(0x0305, 0x1a);
|
||||
bus.write(0x0306, 0xea); // NOP
|
||||
bus.write(0x0307, 0xea); // NOP
|
||||
bus.write(0x0308, 0xa2); // LDX #$03
|
||||
bus.write(0x0309, 0x03);
|
||||
|
||||
bus.write(0x030a, 0xa9); // LDA #$00
|
||||
bus.write(0x030b, 0x00);
|
||||
bus.write(0x030c, 0xa2); // LDX #$00
|
||||
bus.write(0x030d, 0x00);
|
||||
bus.write(0x030e, 0xa0); // LDY #$00
|
||||
bus.write(0x030f, 0x00);
|
||||
|
||||
bus.write(0x0310, 0x4c); // JMP #$0300
|
||||
bus.write(0x0311, 0x00);
|
||||
bus.write(0x0312, 0x03);
|
||||
|
||||
|
||||
long sum = 0;
|
||||
|
||||
// The number of times to run the program
|
||||
long iters = 1000;
|
||||
|
||||
// The number of steps to take when running the program
|
||||
long steps = 100000;
|
||||
|
||||
for (int i = 0; i < iters; i++) {
|
||||
long startTime = System.nanoTime();
|
||||
|
||||
// Reset the CPU (does not clear memory)
|
||||
cpu.reset();
|
||||
|
||||
for (int j = 0; j < steps; j++) {
|
||||
cpu.step();
|
||||
}
|
||||
|
||||
long endTime = System.nanoTime();
|
||||
long diff = endTime - startTime;
|
||||
|
||||
sum += diff;
|
||||
}
|
||||
|
||||
long average = sum / iters;
|
||||
long totalSteps = steps * iters;
|
||||
long avgStep = sum / totalSteps;
|
||||
|
||||
System.out.println("Total instructions executed: " +
|
||||
String.format("%,d", totalSteps));
|
||||
System.out.println("Total time taken: " +
|
||||
String.format("%,d us", sum / 1000));
|
||||
System.out.println("Average time per step: " +
|
||||
avgStep + " ns ");
|
||||
}
|
||||
|
||||
public void profileMemoryReads() {
|
||||
// Create a bus.
|
||||
Bus b = new Bus(0, 65535);
|
||||
|
||||
try {
|
||||
// Create eight devices, each 8KB, to fill the bus.
|
||||
b.addDevice(new Memory(0x0000, 0x2000)); // 8KB @ $0000-$1fff
|
||||
b.addDevice(new Memory(0x2000, 0x2000)); // 8KB @ $2000-$3fff
|
||||
b.addDevice(new Memory(0x4000, 0x2000)); // 8KB @ $4000-$5fff
|
||||
b.addDevice(new Memory(0x6000, 0x2000)); // 8KB @ $6000-$7fff
|
||||
b.addDevice(new Memory(0x8000, 0x2000)); // 8KB @ $8000-$9fff
|
||||
b.addDevice(new Memory(0xa000, 0x2000)); // 8KB @ $a000-$bfff
|
||||
b.addDevice(new Memory(0xc000, 0x2000)); // 8KB @ $c000-$dfff
|
||||
b.addDevice(new Memory(0xe000, 0x2000)); // 8KB @ $e000-$ffff
|
||||
} catch (MemoryRangeException ex) {
|
||||
System.err.println("Memory Range Exception! " + ex.getMessage());
|
||||
return;
|
||||
}
|
||||
|
||||
// Read memory
|
||||
long sum = 0;
|
||||
long average = 0;
|
||||
|
||||
long iters = 500;
|
||||
for (int i = 0; i < iters; i++) {
|
||||
long startTime = System.nanoTime();
|
||||
// Read and assign to a buffer
|
||||
int buf = 0;
|
||||
for (int j = 0; j < 0xffff; j++) {
|
||||
buf = b.read(j);
|
||||
if (buf != 0xff) {
|
||||
System.out.println("WARNING! MEMORY SHOULD HAVE " +
|
||||
"BEEN $FF, WAS: " + buf);
|
||||
System.exit(0);
|
||||
}
|
||||
}
|
||||
|
||||
long endTime = System.nanoTime();
|
||||
long diff = endTime - startTime;
|
||||
|
||||
sum += diff;
|
||||
average = sum / (i + 1);
|
||||
}
|
||||
System.out.println("Average time to read 64KB: " + average +
|
||||
" ns (" + (average / 1000) + " us)");
|
||||
System.out.println("Average time to read one byte: " +
|
||||
sum / (64 * 1024 * iters) + " ns");
|
||||
}
|
||||
}
|
||||
@@ -0,0 +1,109 @@
|
||||
package com.loomcom.symon;
|
||||
|
||||
import com.loomcom.symon.devices.*;
|
||||
import com.loomcom.symon.exceptions.*;
|
||||
|
||||
/**
|
||||
* Main control class for the J6502 Simulator.
|
||||
*/
|
||||
public class Simulator {
|
||||
|
||||
/**
|
||||
* Command-line parser used by this simulator.
|
||||
*/
|
||||
private CommandParser parser;
|
||||
|
||||
/**
|
||||
* The CPU itself.
|
||||
*/
|
||||
private Cpu cpu;
|
||||
|
||||
/**
|
||||
* The Bus responsible for routing memory read/write requests to the
|
||||
* correct IO devices.
|
||||
*/
|
||||
private Bus bus;
|
||||
|
||||
public Simulator() throws MemoryRangeException {
|
||||
cpu = new Cpu();
|
||||
bus = new Bus(0x0000, 0xffff);
|
||||
bus.addCpu(cpu);
|
||||
bus.addDevice(new Memory(0x0000, 0x10000));
|
||||
parser = new CommandParser(System.in, System.out, this);
|
||||
}
|
||||
|
||||
public void run() {
|
||||
parser.run();
|
||||
}
|
||||
|
||||
public void step() {
|
||||
}
|
||||
|
||||
public int read(int address) {
|
||||
return 0;
|
||||
}
|
||||
|
||||
public void write(int address, int value) {
|
||||
}
|
||||
|
||||
/**
|
||||
* A test method.
|
||||
*/
|
||||
|
||||
public void runTest() {
|
||||
|
||||
// Start at 0x0300
|
||||
bus.write(0xfffc, 0x00);
|
||||
bus.write(0xfffd, 0x03);
|
||||
|
||||
bus.write(0x0300, 0xa9); // LDA #$FF
|
||||
bus.write(0x0301, 0xff);
|
||||
bus.write(0x0302, 0xea); // NOP
|
||||
bus.write(0x0303, 0xea); // NOP
|
||||
bus.write(0x0304, 0xea); // NOP
|
||||
bus.write(0x0305, 0xa0); // LDY #$1A
|
||||
bus.write(0x0306, 0x1a);
|
||||
bus.write(0x0307, 0xea); // NOP
|
||||
bus.write(0x0308, 0xea); // NOP
|
||||
bus.write(0x0309, 0xa2); // LDX #$90
|
||||
bus.write(0x030a, 0x90);
|
||||
|
||||
bus.write(0x030b, 0xea); // NOP
|
||||
bus.write(0x030c, 0xea); // NOP
|
||||
bus.write(0x030d, 0xea); // NOP
|
||||
|
||||
bus.write(0x030e, 0xa2); // LDX #$02
|
||||
bus.write(0x030f, 0x02);
|
||||
|
||||
bus.write(0x0310, 0xa9); // LDA #$00
|
||||
bus.write(0x0311, 0x00);
|
||||
bus.write(0x0312, 0xa2); // LDX #$00
|
||||
bus.write(0x0313, 0x00);
|
||||
bus.write(0x0314, 0xa0); // LDY #$00
|
||||
bus.write(0x0315, 0x00);
|
||||
|
||||
bus.write(0x0316, 0x4c); // JMP #$0300
|
||||
bus.write(0x0317, 0x00);
|
||||
bus.write(0x0318, 0x03);
|
||||
|
||||
cpu.reset();
|
||||
|
||||
for (int i = 0; i <= 40; i++) {
|
||||
cpu.step();
|
||||
System.out.println(cpu.toString());
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
/**
|
||||
* Main simulator routine.
|
||||
*/
|
||||
public static void main(String[] args) {
|
||||
try {
|
||||
new Simulator().runTest();
|
||||
} catch (MemoryRangeException ex) {
|
||||
System.err.println("Error: " + ex.toString());
|
||||
}
|
||||
}
|
||||
|
||||
}
|
||||
@@ -0,0 +1,73 @@
|
||||
package com.loomcom.symon.devices;
|
||||
|
||||
import com.loomcom.symon.*;
|
||||
import com.loomcom.symon.exceptions.*;
|
||||
|
||||
/**
|
||||
* A memory-mapped IO Device.
|
||||
*/
|
||||
|
||||
public abstract class Device implements Comparable<Device> {
|
||||
|
||||
/** The memory range for this device. */
|
||||
private MemoryRange memoryRange;
|
||||
|
||||
/** The name of the device. */
|
||||
private String name;
|
||||
|
||||
/** Reference to the bus where this Device is attached. */
|
||||
private Bus bus;
|
||||
|
||||
public Device(int address, int size, String name)
|
||||
throws MemoryRangeException {
|
||||
this.memoryRange = new MemoryRange(address, address + size - 1);
|
||||
this.name = name;
|
||||
}
|
||||
|
||||
public Device(int address, int size) throws MemoryRangeException {
|
||||
this(address, size, null);
|
||||
}
|
||||
|
||||
/* Methods required to be implemented by inheriting classes. */
|
||||
public abstract void write(int address, int data);
|
||||
public abstract int read(int address);
|
||||
public abstract String toString();
|
||||
|
||||
public void setBus(Bus bus) {
|
||||
this.bus = bus;
|
||||
}
|
||||
|
||||
public MemoryRange getMemoryRange() {
|
||||
return memoryRange;
|
||||
}
|
||||
|
||||
public int endAddress() {
|
||||
return memoryRange.endAddress();
|
||||
}
|
||||
|
||||
public int startAddress() {
|
||||
return memoryRange.startAddress();
|
||||
}
|
||||
|
||||
public String getName() {
|
||||
return name;
|
||||
}
|
||||
|
||||
public void setName(String name) {
|
||||
this.name = name;
|
||||
}
|
||||
|
||||
/**
|
||||
* Compares two devices. The sort order is defined by the sort
|
||||
* order of the device's memory ranges.
|
||||
*/
|
||||
public int compareTo(Device other) {
|
||||
if (other == null) {
|
||||
throw new NullPointerException("Cannot compare to null.");
|
||||
}
|
||||
if (this == other) {
|
||||
return 0;
|
||||
}
|
||||
return getMemoryRange().compareTo(other.getMemoryRange());
|
||||
}
|
||||
}
|
||||
@@ -0,0 +1,39 @@
|
||||
package com.loomcom.symon.devices;
|
||||
|
||||
import java.util.*;
|
||||
|
||||
import com.loomcom.symon.*;
|
||||
import com.loomcom.symon.exceptions.*;
|
||||
|
||||
public class Memory extends Device {
|
||||
|
||||
private boolean readOnly;
|
||||
private int[] mem;
|
||||
|
||||
public Memory(int address, int size, boolean readOnly)
|
||||
throws MemoryRangeException {
|
||||
super(address, size, "RW Memory");
|
||||
this.readOnly = readOnly;
|
||||
this.mem = new int[size];
|
||||
// Initialize all locations to 0xff
|
||||
Arrays.fill(this.mem, 0xff);
|
||||
}
|
||||
|
||||
public Memory(int address, int size)
|
||||
throws MemoryRangeException {
|
||||
this(address, size, false);
|
||||
}
|
||||
|
||||
public void write(int address, int data) {
|
||||
this.mem[address] = data;
|
||||
}
|
||||
|
||||
public int read(int address) {
|
||||
return this.mem[address];
|
||||
}
|
||||
|
||||
public String toString() {
|
||||
return "Memory: " + getMemoryRange().toString();
|
||||
}
|
||||
|
||||
}
|
||||
@@ -0,0 +1,11 @@
|
||||
package com.loomcom.symon.exceptions;
|
||||
|
||||
/**
|
||||
* Exception that will be thrown if access to memory or IO cannot be
|
||||
* accessed.
|
||||
*/
|
||||
public class MemoryAccessException extends Exception {
|
||||
public MemoryAccessException(String msg) {
|
||||
super(msg);
|
||||
}
|
||||
}
|
||||
@@ -0,0 +1,10 @@
|
||||
package com.loomcom.symon.exceptions;
|
||||
|
||||
/**
|
||||
* Exception that will be thrown if devices conflict in the IO map.
|
||||
*/
|
||||
public class MemoryRangeException extends Exception {
|
||||
public MemoryRangeException(String msg) {
|
||||
super(msg);
|
||||
}
|
||||
}
|
||||
Reference in new issue
Block a user