Add Mike42 Machine Type

2026-09-25 00:37:52 +01:00
1 parent b9997e3edc
commit 87217afa6e
@@ -0,0 +1,134 @@
+package com.loomcom.symon.machines;
+
+import com.loomcom.symon.Bus;
+import com.loomcom.symon.Cpu;
+import com.loomcom.symon.InstructionTable;
+import com.loomcom.symon.devices.*;
+import com.loomcom.symon.exceptions.MemoryRangeException;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.io.File;
+
+public class MichaelBillingtonMachine implements Machine{
+
+    private static final Logger logger = LoggerFactory.getLogger(MichaelBillingtonMachine.class.getName());
+
+    // Constants used by the simulated system
+    private static final int BUS_BOTTOM = 0x0000;
+    private static final int BUS_TOP    = 0xffff;
+
+    // 32k of ram, from $0000 to $7fff
+    private static final int MEMORY_BASE = 0x0000;
+    private static final int MEMORY_SIZE = 0x8000;
+
+    // VIA at $8000-$800f
+    private static final int PIA_BASE = 0x8000;
+
+    // ACIA at $8400-$8403
+    private static final int ACIA_BASE = 0x8400;
+
+    // 16k ROM from $c000 to $ffff
+    private static final int ROM_BASE = 0xc000;
+    private static final int ROM_SIZE = 0x4000;
+
+    private final   Bus     bus;
+    private final   Cpu     cpu;
+    private final   Acia    acia;
+    private final   Pia     pia;
+    private final   Memory  ram;
+    private         Memory  rom;
+
+    public MichaelBillingtonMachine(String romFile) throws Exception {
+        this.bus = new Bus(BUS_BOTTOM, BUS_TOP);
+        this.cpu = new Cpu();
+        this.ram = new Memory(MEMORY_BASE, MEMORY_BASE + MEMORY_SIZE - 1);
+        this.pia = new Via6522(PIA_BASE);
+        this.acia = new Acia6551(ACIA_BASE);
+
+        bus.addCpu(cpu);
+        bus.addDevice(ram);
+        bus.addDevice(pia);
+        bus.addDevice(acia);
+
+        if (romFile != null) {
+            File romImage = new File(romFile);
+            if (romImage.canRead()) {
+                logger.info("Loading ROM image from file {}", romImage);
+                this.rom = Memory.makeROM(ROM_BASE, ROM_BASE + ROM_SIZE - 1, romImage);
+            } else {
+                logger.info("Default ROM file {} not found, loading empty R/W memory image.", romImage);
+                this.rom = Memory.makeRAM(ROM_BASE, ROM_BASE + ROM_SIZE - 1);
+            }
+        } else {
+            logger.info("No ROM file specified, loading empty R/W memory image.");
+            this.rom = Memory.makeRAM(ROM_BASE, ROM_BASE + ROM_SIZE - 1);
+        }
+
+        bus.addDevice(rom);
+    }
+
+    @Override
+    public Bus getBus() {
+        return bus;
+    }
+
+    @Override
+    public Cpu getCpu() {
+        return cpu;
+    }
+
+    @Override
+    public Memory getRam() {
+        return ram;
+    }
+
+    @Override
+    public Acia getAcia() {
+        return acia;
+    }
+
+    @Override
+    public Pia getPia() {
+        return pia;
+    }
+
+    @Override
+    public Crtc getCrtc() {
+        return null;
+    }
+
+    @Override
+    public Memory getRom() {
+        return rom;
+    }
+
+    @Override
+    public void setRom(Memory rom) throws MemoryRangeException {
+        if (this.rom != null) {
+            bus.removeDevice(this.rom);
+        }
+        this.rom = rom;
+        bus.addDevice(this.rom);
+    }
+
+    @Override
+    public int getRomBase() {
+        return ROM_BASE;
+    }
+
+    @Override
+    public int getRomSize() {
+        return ROM_SIZE;
+    }
+
+    @Override
+    public int getMemorySize() {
+        return MEMORY_SIZE;
+    }
+
+    @Override
+    public String getName() {
+        return "mike42";
+    }
+}