private void DispatchOpcode(ParsedOpCode parsedOpCode)
{
switch (parsedOpCode.Instruction)
{
case 0x0:
// 0xE0 Clear Display
if (parsedOpCode.NN == 0xE0)
{
DisplayModel.Clear();
}
// 0xEE Return from Subroutine
else if (parsedOpCode.NN == 0xEE)
{
CPU.Ret();
}
break;
case 0x01:
// 0x1NNN Jump to address NNN
CPU.Jump(parsedOpCode.NNN);
break;
case 0x02:
// 0x2NNN Execute subroutine at address NNN
CPU.Subroutine(parsedOpCode.NNN);
break;
case 0x03:
// 0x3XNN Skip the next instruction if regoster VX == NN
CPU.SkipIfEqual(parsedOpCode.X, parsedOpCode.NN);
break;
case 0x04:
// 0x4XNN Skip the next instruction if register VX != NN
CPU.SkipIfNotEqual(parsedOpCode.X, parsedOpCode.NN);
break;
case 0x05:
// 0x5XY0 Skip the next instruction if register VX == VY
CPU.SkipIfXEqY(parsedOpCode.X, parsedOpCode.Y);
break;
case 0x06:
// 0x6XNN Store the number NN in register VX
CPU.StoreInRegister(parsedOpCode.X, parsedOpCode.NN);
break;
case 0x07:
// 0x7XNN Add the number NN to register VX
CPU.AddToRegister(parsedOpCode.X, parsedOpCode.NN);
break;
case 0x08:
// Handle opcodes starting with 0x08 in a separate function
Dispatch0x08(parsedOpCode);
break;
case 0x09:
// 0x9XY0 Skip the next instruction if register VX != VY
if (parsedOpCode.N == 0)
{
CPU.SkipNextInstructionIfVXneVY(parsedOpCode.X, parsedOpCode.Y);
}
break;
case 0x0A:
// 0xANNN Store memeory at address NNN in register I
CPU.Index = parsedOpCode.NNN;
break;
case 0x0B:
// 0xBNNN Jump to address NNN plus V0
CPU.JumpToAddressPlusV0(parsedOpCode.NNN);
break;
case 0x0C:
// 0xCXNN Set VX to a random number with a mask of NN
byte number = (byte)(random.Next(parsedOpCode.NN));
CPU.V[parsedOpCode.X] = number;
break;
case 0x0D:
// 0xDXYN Draw sprite at position VX, VY with N bytes of data at the address stored in I
// Set VF to 1 if any set pixels become unset. Set VF to 0 otherwise.
var unsetPixels = DisplayModel.DrawSprite(CPU.V[parsedOpCode.X], CPU.V[parsedOpCode.Y], Memory, CPU.Index, parsedOpCode.N);
CPU.V[0x0F] = (byte)(unsetPixels ? 1 : 0);
break;
case 0x0E:
// Handle opcodes begining with 0xE
Dispatch0x0E(parsedOpCode);
break;
case 0x0F:
// Handle opcodes begining with 0xF
Dispatch0x0F(parsedOpCode);
break;
}
}
