IBM DeveloperWorks has published a new two-part tutorial on microcontrollers. The first part covers the basics of hardware and development tools and gets into circuit design. Sample code and schematics are included. The second part of the tutorial deals with the design of a simple navigation system for a small robot called IrBot. The robot uses a Palm OS device as a wireless controller. As with part one, all schematics and source code are included in the tutorial. If you have not used the tutorials on IBM DeveloperWorks before, you will need to fill out a short, free registration to access them but it's well worth the time if you're looking for an good introduction to microcontrollers.