public void Jsr_RegisterOperand_PCSetToRegisterValue()
{
var prev = new MutableState()
.Set(Register.A, 0x10);
var next = new Jsr(new Reg(Register.A)).Apply(prev);
Assert.AreEqual(0x10, next.Get(Register.PC));
}
public static MutableState ReadFromFile(string path)
{
var state = new MutableState();
var image = Dcpu.LoadImage(path);
Array.Copy (image, state._memory, Dcpu.MAX_ADDRESS + 1);
return state;
}
public void Jsr_RegisterOperand_PCValuePushedOnStack()
{
var prev = new MutableState()
.Set(Register.A, 0x10)
.Set(Register.PC, 0x5)
.Set(Register.SP, 0xFFFF);
var next = new Jsr(new Reg(Register.A)).Apply(prev);
Assert.AreEqual(5, next.Get(0xFFFE));
Assert.AreEqual(0xFFFE, next.Get(Register.SP));
}
public void FetchNextInstruction_InstructionGetsCorrectlyDecoded()
{
var state = new MutableState()
.Set((ushort)0, 0x7C02) // ADD A, next word
.Set((ushort)1, 0x002A); // 42
ushort pc=0, sp=0;
var op = Dcpu.FetchNextInstruction(state, ref pc, ref sp);
Assert.AreEqual(2, pc);
Assert.IsTrue(op is Add);
state = op.Apply(state);
Assert.AreEqual(42, state.Get(Register.A));
}