Have you ever wanted to write some software that interfaces with a physical device? For example, have you ever thought of writing a program that tells you why your ‘check engine’ light is on? If you have, then what you want to do is some serial programming. This article is going to teach you the basics about serial programming, starting off with common definitions right through to how to structure and write your application using REALbasic. This one is so hot and juicey, we had to install an extra refridgeration unit in the server room.