One of the primary routes to hacking these earlier copy protections had been to run a program that simulates the normal CPU operation. The CPU simulator provides a quantity of extra features to the hacker, such as the ability to single-step through each cpu instruction and to examine the PROCESSOR registers and revised memory spaces since the simulation works any modern disassembler/debugger can do this specific. The Apple II provided a built-in opcode disassembler, allowing raw memory to be able to be decoded in to CPU opcodes, which would be used to examine just what the copy-protection involved to do following. Generally there was little to no defense available to typically the copy protection program, since all the secrets are made visible with the simulation. However, since the ruse itself must work on the initial CPU, in add-on to the software being hacked, the simulation would frequently run extremely slowly even at maximum speed.