Skip to content

Commit

Permalink
Refactor multiple components and add new unit tests
Browse files Browse the repository at this point in the history
  • Loading branch information
@craigthomas
craigthomas committed Feb 19, 2025
1 parent 491e389 commit ae7a6f3
Show file tree
Hide file tree
Showing 14 changed files with 328 additions and 77 deletions.
1 change: 0 additions & 1 deletion src/main/java/ca/craigthomas/yacoco3e/components/BranchInstruction.java
View file
Original file line number Diff line number Diff line change
Expand Up @@ -39,7 +39,6 @@ public int call(IOController io) {
if (operation.apply(io).equals(true)) {
io.regs.pc.add(byteRead.isNegative() ? byteRead.getSignedShort() : byteRead.getShort());
}

return ticks;
}

Expand Down
4 changes: 1 addition & 3 deletions src/main/java/ca/craigthomas/yacoco3e/components/ByteRegisterInstruction.java
View file
Original file line number Diff line number Diff line change
Expand Up @@ -239,9 +239,7 @@ public static void decimalAdditionAdjust(IOController io, UnsignedByte registerB
}
io.regs.a.set(new UnsignedByte(io.regs.a.getShort() + result.getShort()));
io.regs.cc.or(io.regs.a.isZero() ? CC_Z : 0);
io.regs.cc.or(carryPreviouslySet ? CC_C : 0);
io.regs.cc.or(result.isNegative() ? CC_N : 0);
io.regs.a.set(result);
io.regs.cc.or(io.regs.a.isNegative() ? CC_N : 0);
}


Expand Down
66 changes: 22 additions & 44 deletions src/main/java/ca/craigthomas/yacoco3e/components/CPU.java
View file
Original file line number Diff line number Diff line change
Expand Up @@ -14,15 +14,13 @@
public class CPU
{
/* CPU Internal Variables */
private UnsignedWord lastPC;
private UnsignedByte lastOperand;
private final IOController io;
public Instruction instruction;

/* Interrupt request flags */
private boolean fireIRQ;
private boolean fireFIRQ;
private boolean fireNMI;
protected boolean fireIRQ;
protected boolean fireFIRQ;
protected boolean fireNMI;

public CPU(IOController ioController) {
io = ioController;
Expand All @@ -35,8 +33,8 @@ public CPU(IOController ioController) {
* @return the number of ticks taken up by the instruction
*/
public int executeInstruction() throws MalformedInstructionException {
UnsignedWord opWord = io.readWord(io.regs.pc);
instruction = InstructionTable.get(opWord);
UnsignedWord op = io.readWord(io.regs.pc);
instruction = InstructionTable.get(op);
return instruction.execute(io);
}

Expand All @@ -56,7 +54,7 @@ public void interruptRequest() {
io.regs.cc.or(CC_E);
io.pushStack(Register.S, io.regs.cc);
io.regs.cc.or(CC_I);
io.regs.pc.set(io.readWord(new UnsignedWord(0xFFF8)));
io.regs.pc.set(io.readWord(0xFFF8));
}

/**
Expand All @@ -70,7 +68,7 @@ public void fastInterruptRequest() {
io.pushStack(Register.S, io.regs.cc);
io.regs.cc.or(CC_F);
io.regs.cc.or(CC_I);
io.regs.pc.set(io.readWord(new UnsignedWord(0xFFF6)));
io.regs.pc.set(io.readWord(0xFFF6));
}

/**
Expand All @@ -90,75 +88,55 @@ public void nonMaskableInterruptRequest() {
io.pushStack(Register.S, io.regs.cc);
io.regs.cc.or(CC_I);
io.regs.cc.or(CC_F);
io.regs.pc.set(io.readWord(new UnsignedWord(0xFFFC)));
}

/**
* Schedules an IRQ interrupt to occur.
*/
public void scheduleIRQ() {
fireIRQ = true;
}

public boolean irqWaiting() {
return fireIRQ;
}

public void clearIRQ() {
fireIRQ = false;
io.regs.pc.set(io.readWord(0xFFFC));
}

/**
* Check to see if there was any interrupt request. If so, execute the code associated
* with it.
*/
public void serviceInterrupts() {
if (fireIRQ | fireFIRQ | fireNMI) {
io.waitForIRQ = false;
}

if (fireIRQ) {
interruptRequest();
clearIRQ();
fireIRQ = false;
}

if (fireFIRQ) {
fastInterruptRequest();
clearFIRQ();
fireFIRQ = false;
}

if (fireNMI) {
nonMaskableInterruptRequest();
clearNMI();
fireNMI = false;
}
}

/**
* Schedules an IRQ interrupt to occur.
*/
public void scheduleIRQ() {
fireIRQ = true;
}

/**
* Schedules a fast interrupt to occur.
*/
public void scheduleFIRQ() {
fireFIRQ = true;
}

public boolean firqWaiting() {
return fireFIRQ;
}

public void clearFIRQ() {
fireFIRQ = false;
}

/**
* Schedules a non-maskable interrupt to occur.
*/
public void scheduleNMI() {
fireNMI = true;
}

public boolean nmiWaiting() {
return fireNMI;
}

public void clearNMI() {
fireNMI = false;
}

public void reset() {

}
Expand Down
29 changes: 16 additions & 13 deletions src/main/java/ca/craigthomas/yacoco3e/components/Emulator.java
View file
Original file line number Diff line number Diff line change
Expand Up @@ -25,7 +25,7 @@ public class Emulator extends Thread
private Screen screen;
private Keyboard keyboard;
private CPU cpu;
private IOController ioController;
private IOController io;
private Cassette cassette;
private Memory memory;

Expand Down Expand Up @@ -105,9 +105,9 @@ private Emulator(Builder builder) {
keyboard = new EmulatedKeyboard();
screen = new Screen(builder.scale);
cassette = new Cassette();
ioController = new IOController(memory, new RegisterSet(), keyboard, screen, cassette);
cpu = new CPU(ioController);
ioController.setCPU(cpu);
io = new IOController(memory, new RegisterSet(), keyboard, screen, cassette);
cpu = new CPU(io);
io.setCPU(cpu);
trace = builder.trace;
verbose = builder.verbose;
status = EmulatorStatus.STOPPED;
Expand Down Expand Up @@ -192,7 +192,7 @@ public void loadFromConfigFile(ConfigFile config) {
if (drive0 != null) {
JV1Disk disk = new JV1Disk();
if (disk.loadFile(drive0)) {
ioController.disk[0].loadFromVirtualDisk(disk);
io.disk[0].loadFromVirtualDisk(disk);
}
}
}
Expand All @@ -202,7 +202,7 @@ public void loadFromConfigFile(ConfigFile config) {
*/
public void reset() {
memory.resetMemory();
ioController.reset();
io.reset();
cpu.reset();
}

Expand Down Expand Up @@ -379,7 +379,7 @@ public void switchKeyListener(Keyboard newKeyboard) {
canvas.removeKeyListener(keyboard);
canvas.addKeyListener(newKeyboard);
keyboard = newKeyboard;
ioController.setKeyboard(keyboard);
io.setKeyboard(keyboard);
}

/**
Expand All @@ -404,7 +404,7 @@ private void refreshScreen()
* 60th of a second time slice.
*/
public void refreshTicks() {
remainingTicks = ioController.tickRefreshAmount;
remainingTicks = io.tickRefreshAmount;
}

/**
Expand Down Expand Up @@ -435,21 +435,23 @@ public void run() {
while (status != EmulatorStatus.KILLED) {
while (status == EmulatorStatus.RUNNING) {
if (this.trace) {
System.out.print(ioController.regs.toString() + " | ");
System.out.print(io.regs.toString() + " | ");
}

try {
if (remainingTicks > 0) {
if (remainingTicks > 0 && !io.waitForIRQ) {
operationTicks = cpu.executeInstruction();
remainingTicks -= operationTicks;
remainingTicks = remainingTicks - operationTicks;
}
} catch (MalformedInstructionException e) {
System.out.println(e.getMessage());
status = EmulatorStatus.PAUSED;
}

/* Increment timers if necessary */
ioController.timerTick(operationTicks);
io.timerTick(operationTicks);

// System.out.print(" new pc: " + ioController.regs.pc);

/* Fire interrupts if set */
cpu.serviceInterrupts();
Expand All @@ -460,6 +462,7 @@ public void run() {
// + cpu.getLastOperand() + " | " + cpu.instruction.getShortDescription());
if (cpu.instruction != null) {
System.out.print(cpu.instruction.getShortDescription());
System.out.print(" new pc: " + io.regs.pc);
System.out.println();
}
}
Expand Down Expand Up @@ -492,7 +495,7 @@ public Memory getMemory() {
}

public IOController getIOController() {
return ioController;
return io;
}

public Cassette getCassette() {
Expand Down
6 changes: 5 additions & 1 deletion src/main/java/ca/craigthomas/yacoco3e/components/IOController.java
View file
Original file line number Diff line number Diff line change
Expand Up @@ -72,6 +72,9 @@ public class IOController
/* GIME FIRQ status */
public UnsignedByte firqStatus;

/* Whether the CPU should wait for an interrupt request */
public boolean waitForIRQ;

/* The number of ticks to pass in 63.5 microseconds */
public static final int TIMER_63_5_MICROS = 56;

Expand Down Expand Up @@ -166,6 +169,7 @@ public IOController(Memory memory, RegisterSet registerSet, Keyboard keyboard, S

samClockSpeed = new UnsignedByte();
tickRefreshAmount = LOW_SPEED_CLOCK_FREQUENCY;
waitForIRQ = false;
}

/**
Expand Down Expand Up @@ -1189,7 +1193,7 @@ public void reset() {
memory.disableAllRAMMode();

/* Load PC with Reset Interrupt Vector */
regs.pc = readWord(new UnsignedWord(0xFFFE));
regs.pc = readWord(0xFFFE);
}

/**
Expand Down
22 changes: 11 additions & 11 deletions src/main/java/ca/craigthomas/yacoco3e/components/Instruction.java
View file
Original file line number Diff line number Diff line change
Expand Up @@ -153,7 +153,7 @@ public void getIndexed(IOController io) throws MalformedInstructionException {
UnsignedWord r;
UnsignedWord d;
UnsignedByte n;
UnsignedWord nWord;
UnsignedWord w;
numBytesRead = 1;

/* 5-bit offset - check for signed values */
Expand Down Expand Up @@ -248,10 +248,10 @@ public void getIndexed(IOController io) throws MalformedInstructionException {
/* n,R -> 16-bit offset from R */
case 0x09:
r = io.getWordRegister(io.getIndexedRegister(postByte));
nWord = io.readWord(io.regs.pc);
w = io.readWord(io.regs.pc);
io.regs.incrementPC();
io.regs.incrementPC();
addressRead = new UnsignedWord(r.getInt() + nWord.getSignedInt());
addressRead = new UnsignedWord(r.getInt() + w.getSignedInt());
wordRead = io.readWord(addressRead);
byteRead = wordRead.getHigh();
numBytesRead = 3;
Expand Down Expand Up @@ -280,10 +280,10 @@ public void getIndexed(IOController io) throws MalformedInstructionException {
/* n,PC -> 16-bit offset from PC */
case 0x0D:
r = io.getWordRegister(Register.PC);
nWord = io.readWord(io.regs.pc);
w = io.readWord(io.regs.pc);
io.regs.incrementPC();
io.regs.incrementPC();
addressRead = new UnsignedWord(r.getInt() + nWord.getSignedInt());
addressRead = new UnsignedWord(r.getInt() + w.getSignedInt());
wordRead = io.readWord(addressRead);
byteRead = wordRead.getHigh();
numBytesRead = 3;
Expand Down Expand Up @@ -345,10 +345,10 @@ public void getIndexed(IOController io) throws MalformedInstructionException {
/* [n,R] -> 16-bit offset from R - indirect */
case 0x19:
r = io.getWordRegister(io.getIndexedRegister(postByte));
nWord = io.readWord(io.regs.pc);
w = io.readWord(io.regs.pc);
io.regs.incrementPC();
io.regs.incrementPC();
addressRead = io.readWord(new UnsignedWord(r.getInt() + nWord.getSignedInt()));
addressRead = io.readWord(new UnsignedWord(r.getInt() + w.getSignedInt()));
wordRead = io.readWord(addressRead);
byteRead = wordRead.getHigh();
numBytesRead = 3;
Expand Down Expand Up @@ -376,21 +376,21 @@ public void getIndexed(IOController io) throws MalformedInstructionException {
/* [n,PC] -> 16-bit offset from PC - indirect */
case 0x1D:
r = io.getWordRegister(Register.PC);
nWord = io.readWord(io.regs.pc);
w = io.readWord(io.regs.pc);
io.regs.incrementPC();
io.regs.incrementPC();
addressRead = io.readWord(new UnsignedWord(r.getInt() + nWord.getSignedInt()));
addressRead = io.readWord(new UnsignedWord(r.getInt() + w.getSignedInt()));
wordRead = io.readWord(addressRead);
byteRead = wordRead.getHigh();
numBytesRead = 3;
return;

/* [n] -> extended indirect */
case 0x1F:
nWord = io.readWord(io.regs.pc);
w = io.readWord(io.regs.pc);
io.regs.incrementPC();
io.regs.incrementPC();
addressRead = io.readWord(nWord);
addressRead = io.readWord(w);
wordRead = io.readWord(addressRead);
byteRead = wordRead.getHigh();
numBytesRead = 3;
Expand Down
8 changes: 8 additions & 0 deletions src/main/java/ca/craigthomas/yacoco3e/components/Memory.java
View file
Original file line number Diff line number Diff line change
Expand Up @@ -207,6 +207,10 @@ public UnsignedByte readROMByte(int address) {
return new UnsignedByte(rom[0x3FF0 + (address & 0x000F)]);
}

public void writeByte(int address, int value) {
writeByte(new UnsignedWord(address), new UnsignedByte(value));
}

/**
* Writes an UnsignedByte to the specified memory address. If the system
* is in a ROM mode, will not write bytes to a ROM location.
Expand Down Expand Up @@ -332,6 +336,10 @@ public void setTaskPAR(int par, UnsignedByte value) {
taskPAR[par] = value.getShort();
}

public UnsignedByte readByte(int address) {
return readByte(new UnsignedWord(address));
}

/**
* Reads an UnsignedByte from the specified address.
*
Expand Down
Loading

0 comments on commit ae7a6f3

Please sign in to comment.