Implement SimpleMachine

src/main/java/com/loomcom/symon/machines/SimpleMachine.java

@@ -0,0 +1,93 @@
+package com.loomcom.symon.machines;
+
+import com.loomcom.symon.Bus;
+import com.loomcom.symon.Cpu;
+import com.loomcom.symon.devices.Acia;
+import com.loomcom.symon.devices.Crtc;
+import com.loomcom.symon.devices.Memory;
+import com.loomcom.symon.devices.Via;
+import com.loomcom.symon.exceptions.MemoryRangeException;
+
+/**
+ * A SimpleMachine is the simplest 6502 implementation possible - it
+ * consists solely of RAM and a CPU. This machine is primarily useful
+ * for running 6502 functional tests or debugging by hand.
+ */
+public class SimpleMachine implements Machine {
+
+    private static final int BUS_BOTTOM = 0x0000;
+    private static final int BUS_TOP    = 0xffff;
+
+    private final Bus bus;
+    private final Memory ram;
+    private final Cpu cpu;
+
+    public SimpleMachine() throws MemoryRangeException {
+        this.bus = new Bus(BUS_BOTTOM, BUS_TOP);
+        this.ram = new Memory(BUS_BOTTOM, BUS_TOP, false);
+        this.cpu = new Cpu();
+
+        bus.addCpu(cpu);
+        bus.addDevice(ram);
+    }
+
+    @Override
+    public Bus getBus() {
+        return bus;
+    }
+
+    @Override
+    public Cpu getCpu() {
+        return cpu;
+    }
+
+    @Override
+    public Memory getRam() {
+        return ram;
+    }
+
+    @Override
+    public Acia getAcia() {
+        return null;
+    }
+
+    @Override
+    public Via getVia() {
+        return null;
+    }
+
+    @Override
+    public Crtc getCrtc() {
+        return null;
+    }
+
+    @Override
+    public Memory getRom() {
+        return null;
+    }
+
+    @Override
+    public void setRom(Memory rom) throws MemoryRangeException {
+        // No-op
+    }
+
+    @Override
+    public int getRomBase() {
+        return 0;
+    }
+
+    @Override
+    public int getRomSize() {
+        return 0;
+    }
+
+    @Override
+    public int getMemorySize() {
+        return BUS_TOP + 1;
+    }
+
+    @Override
+    public String getName() {
+        return "Simple";
+    }
+}