Book excerpt: This text gives an introduction to MIPS Assembler using the PCSPIM simulator emphasizing software development. The object is to make high-level language programmers of embedded processors aware of what their compilers must do, what actually happens inside the hardware of their computers, and how these facts may well affect their programming decisions. The MIPS processor is chosen as the example of a real processor with a significant market that is still very simply and cleanly designed.The availability of an excellent free simulator makes this a good choice.