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DylanSpeiserDylanSpeiser
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Merge pull request #13 from ae6ch/master
Awesome work! Merging "Added ACIA support"
2 parents 0c88844 + 81e47d2 commit c39204f

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5 files changed

+120
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5 files changed

+120
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lines changed

‎src/ACIA.java‎

Lines changed: 100 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,100 @@
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import java.util.Scanner;
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public class ACIA {
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private byte dataRegister = 0;
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private byte commandRegister = 0;
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private byte statusRegister =0;
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private byte controlRegister = 0;
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private Scanner s;
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public ACIA() {
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s = new Scanner(System.in);
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}
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/**
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* @return theF dataRegister
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*/
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public byte getDataRegister() {
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return dataRegister;
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}
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/**
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* @return the commandRegister
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*/
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public byte getCommandRegister() {
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return commandRegister;
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}
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/**
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* @return the statusRegister
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*/
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public byte getStatusRegister() {
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return statusRegister;
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}
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/**
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* @return the controlRegister
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*/
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public byte getControlRegister() {
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return controlRegister;
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}
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public byte read(short address) {
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switch (Short.toUnsignedInt(address) - Bus.ACIA_ADDRESS) {
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case 0x00:
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try {
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dataRegister = (byte) System.in.read();
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if (dataRegister == 0xa) dataRegister = 0xd; //convert \n to \r
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} catch (Exception e) {
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System.err.println("Error reading from System.in");
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}
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return dataRegister; // Read Receiver Data Register
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case 0x01:
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try {
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if (System.in.available() >= 1) { // TODO: Remove this later when we go to a windowed interface
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statusRegister = 1 << 3;
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} else {
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statusRegister = 0 << 3;
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}
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} catch (Exception e) {
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System.err.println("Error reading from System.in");
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}
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return statusRegister; // Read Status Register
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case 0x02:
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return commandRegister; // Read Command Register
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case 0x03:
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return controlRegister; // Read Control Register
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default:
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System.err.printf("Attempted to read from invalid ACIA register: %04x\n", address);
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return 0;
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}
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}
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public void write(short address, byte data) {
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switch (Short.toUnsignedInt(address) - Bus.ACIA_ADDRESS) {
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case 0x00:
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System.out.printf("%c", data); // Write Transmitter Data Register
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if (data == 0xd) System.out.printf("\n"); // convert \r to \n
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case 0x01: // Programmed Reset
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// Clear bits 4 through 0 in the Command Register and bit 2 in the Status
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// Register
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case 0x02:
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commandRegister = data;
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break; // Write Command Register
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case 0x03:
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controlRegister = data;
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break; // Write Control Register
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default:
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System.err.printf("Attempted to write to invalid ACIA register: %04x\n", address);
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}
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}
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}

‎src/Bus.java‎

Lines changed: 5 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -1,11 +1,14 @@
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public class Bus {
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public static int VIA_ADDRESS = 0x7ff0;
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public static int ACIA_ADDRESS = 0x5000;
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public static byte read(short address) {
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if (Short.toUnsignedInt(address) >= 0x8000) {
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return EaterEmulator.rom.read((short)(address-0x8000));
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} else if (Short.toUnsignedInt(address) <= VIA_ADDRESS+16 && Short.toUnsignedInt(address) >= VIA_ADDRESS) {
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return EaterEmulator.via.read(address);
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} else if (Short.toUnsignedInt(address) <= ACIA_ADDRESS+3 && Short.toUnsignedInt(address) >= ACIA_ADDRESS) {
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return EaterEmulator.acia.read(address);
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} else {
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return EaterEmulator.ram.read(address);
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}
@@ -16,6 +19,8 @@ public static void write(short address, byte data) {
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System.err.println("Can't write to ROM! ("+Integer.toHexString(Short.toUnsignedInt(address)).toUpperCase()+")");
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} else if (Short.toUnsignedInt(address) <= VIA_ADDRESS+16 && Short.toUnsignedInt(address) >= VIA_ADDRESS) {
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EaterEmulator.via.write(address, data);
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} else if (Short.toUnsignedInt(address) <= ACIA_ADDRESS+3 && Short.toUnsignedInt(address) >= ACIA_ADDRESS) {
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EaterEmulator.acia.write(address, data);
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} else {
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EaterEmulator.ram.write(address, data);
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}

‎src/CPU.java‎

Lines changed: 6 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -111,6 +111,7 @@ public CPU() {
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lookup[0xC4] = new Instruction("CPY","ZPP",3);
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lookup[0xCC] = new Instruction("CPY","ABS",4);
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lookup[0x3A] = new Instruction("DEC","IMP", 2); // NEW for wozmon, need to verify cycles
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lookup[0xC6] = new Instruction("DEC","ZPP",5);
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lookup[0xD6] = new Instruction("DEC","ZPX",6);
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lookup[0xCE] = new Instruction("DEC","ABS",6);
@@ -1019,7 +1020,11 @@ public void CPY() {
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public void DEC() {
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fetch();
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int temp = (Byte.toUnsignedInt(fetched)-1);
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Bus.write(addressAbsolute, (byte)(temp&0x00FF));
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if (lookup[Byte.toUnsignedInt(opcode)].addressMode.equals("IMP")) {
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a = (byte) temp;
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} else {
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Bus.write(addressAbsolute, (byte)(temp&0x00FF));
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}
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setFlag('Z',(temp&0x00FF)==0x0000);
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setFlag('N',(temp&0x0080)==0x0080);
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}

‎src/DisplayPanel.java‎

Lines changed: 8 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -122,6 +122,14 @@ public void paintComponent(Graphics g) {
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g.drawString(" IFR: "+ROMLoader.padStringWithZeroes(Integer.toBinaryString(Byte.toUnsignedInt(EaterEmulator.via.IFR)), 8)+" ("+ROMLoader.byteToHexString(EaterEmulator.via.IFR)+")", 35, 670);
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g.drawString(" IER: "+ROMLoader.padStringWithZeroes(Integer.toBinaryString(Byte.toUnsignedInt(EaterEmulator.via.IER)), 8)+" ("+ROMLoader.byteToHexString(EaterEmulator.via.IER)+")", 35, 700);
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//ACIA
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g.drawString("ACIA Registers:",350,490);
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g.drawString("Data Register: "+ROMLoader.padStringWithZeroes(Integer.toBinaryString(Byte.toUnsignedInt(EaterEmulator.acia.getDataRegister())), 8)+" ("+ROMLoader.byteToHexString(EaterEmulator.acia.getDataRegister())+")", 325, 520);
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g.drawString("Command Register: "+ROMLoader.padStringWithZeroes(Integer.toBinaryString(Byte.toUnsignedInt(EaterEmulator.acia.getCommandRegister())), 8)+" ("+ROMLoader.byteToHexString(EaterEmulator.acia.getCommandRegister())+")", 325, 550);
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g.drawString("Status Register: "+ROMLoader.padStringWithZeroes(Integer.toBinaryString(Byte.toUnsignedInt(EaterEmulator.acia.getStatusRegister())), 8)+" ("+ROMLoader.byteToHexString(EaterEmulator.acia.getStatusRegister())+")", 325, 580);
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g.drawString("Control Register: "+ROMLoader.padStringWithZeroes(Integer.toBinaryString(Byte.toUnsignedInt(EaterEmulator.acia.getControlRegister())), 8)+" ("+ROMLoader.byteToHexString(EaterEmulator.acia.getControlRegister())+")", 325, 610);
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//Controls
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if (!EaterEmulator.keyboardMode) {

‎src/EaterEmulator.java‎

Lines changed: 1 addition & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -39,6 +39,7 @@ public class EaterEmulator extends JFrame implements ActionListener {
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public static ROM rom = new ROM();
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public static LCD lcd = new LCD();
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public static VIA via = new VIA();
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public static ACIA acia = new ACIA();
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public static Bus bus = new Bus();
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public static CPU cpu = new CPU();
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public static GPU gpu = new GPU(ram,false);

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