cpu.py

from ram import RAM

# 0x00 -> add one to register 0
# 0x01 -> add one to register 1
# 0x09 -> register 0 = register 0 + register 1
# 0xde 0x?? -> load the value at 0x?? in memory into register 0
# 0xed 0x?? 0x!! -> store 0x!! at 0x?? in memory
# 0xee 0x?? 0xrr -> store registers[0xrr] at 0x?? in memory

# 0xde 0xde 0x00 0x00 0x01 0x01 0x09 0xed 0x00 0x01

class CPU:
    ram = RAM()
    registers = [0] * 4
    ip = 0

    def step():
        # fetch instruction
        instruction = ram.read(ip)
        # decoding the instruction
        if instruction == '\x00':
            # execute
            register[0] += 1
        if instruction == '\x01':
            # execute
            register[1] += 1
        if instruction == '\x09':
            # execute
            register[0] += register[1]
        if instruction == '\xde':
            ip += 1
            index = ram.read(ip)
            register[0] = index
        if instruction == '\xed':
            ip += 1
            index = ram.read(ip)
            ip += 1
            value = ram.read(ip)
            ram.write(value, index)
        if instruction == '\xee':
            ip += 1
            index = ram.read(ip)
            ip += 1
            register_index = ram.read(ip)
            ram.write(registers[register_index], index)
        ip += 1

ram.py

bytes_of_memory = 128

class RAM:
    memory = [0] * bytes_of_memory

    def write(self, what, where):
        self.memory[where] = what

    def read(self, where):
        return self.memory[where]