An emulation system that provides the functionality of an emulated computer on a host computer pre-processes the object code file to be emulated to reduce the run-time overhead due to parsing the object code. The emulator uses pre-programmed functions that model each instruction of the emulated computer. An object code file is pre-parsed to generate a translated file which includes a sequence of function calls corresponding to the sequence of instructions in the code file. The translated file is compiled to generate a corresponding translated object-code file. The translated object-code file is executed in the emulation environment on the host computer. The emulation system also includes a standard mode in which the object code file is emulated by sequentially parsing each instruction in the object code file and invoking an appropriate one of the preprogrammed functions in the emulated environment.