Overview

Embedded system design is made up of two main aspects, the hardware and the software. In the early days of microprocessors, systems were built up laboriously using a large number of integrated circuits (ICs). Memory was very limited, so only small programs could be written. Slowly, the available ICs became more and more sophisticated, and the designer had to do less to get a working hardware system. Meanwhile memory was growing, so longer programs could be written. Now we are in a situation where memory is plentiful and cheap, and the hardware is sophisticated and readily available. Complex hardware systems can be built up with comparative ease, and in many projects software development is now the main creative activity. In this chapter we start down the long but exciting road to developing good programs. We start that road using the Assembler programming language.

We have one problem if we are to start programming. What will the program run on? Ultimately, of course, embedded systems programs are written to run on the target system hardware. You may be working with an educational PIC hardware system, or something else. In many cases, however, we don't want to be dependent on hardware to try out a programming idea. What can really cause a study of programming to spring to life is a simulator a program running on a desktop computer that will run the program we have developed. Therefore, we make it a priority in this chapter to introduce the Microchip MPLAB Integrated...