CPU Sim is a software development environment for the simulation of simple computers.
It was developed by Dale Skrien to help students understand computer architectures.
A sample computer system, the Wombat 1, is provided with CPU Sim.
It has the following registers: The assembly language of the Wombat 1 computer consists of 12 instructions.
The following modification of the program is also used sometimes: This one can use negative input to subtract, or 0 to break the loop.