Okay, here's my two cents (I believe that's approximatly a tuppence Steve and Andy) worth. Write a simple program yourself. This is my advice even if you aren't taking a class. What I mean is that you should write out the assembler mneumonics just as though you were going to assemble it. Then assemble the code yourself. Translate the program into hexadecimal and binary. Write your own Intel Hex file and use Hyperterminal to download it while watching the the communication transactions on a logic analyzer or oscilloscope. Obviously this isn't a practical approach for real applications. But this will give you an inordinant insight into just what is going on when you use an IDE (Integrated Development Environment) to develope more complicated projects. Andy and Steve are quite correct about understanding the hardware. µ-controllers/µ-processors are the nexus where software and hardware meet. The more intimately you can understand both, the better.