This is the overview for the NOPinstruction:

Op Code   Mnemonic Meaning
Hex Dec    
0x00 0 NOP Do nothing.

And here is its implementation:

    public boolean decodeAndExecute(int instruction) {
        switch (instruction) {
            case 0x00:
                // NOP
                break;
            case 0x76:
                // HLT
                return false;
            default:
                throw new RuntimeException("Unknown opcode 0x" + String.format("%02x", instruction));
        }
        return true;
    }

Now, the NOP opcode just exits the switch statement without doing anything, just like it should. At the end, true is returned to indicate that execution should continue with the next instruction.

If you have followed this course up to now, you will now have the foundation of a microcomputer simulation.

Let’s write our first little program