I certainly agree with Andy's statement, but I'd say you're going to have a hard time programming if you have to look up the instructions each time. Memorizing the instructions won't make you a good programmer, but not remembering them is going to make it much less likely that you can be a good and efficient programmer. It's a matter of knowing what suite of instructions is out there and available, and then using the right ones to get the job done. The first part of that sentence requires "memorization" while the second requires experience and an analytical process that can improve over time with practice.

I wouldn't recommend that anyone just sits down and studies the instruction set until they have it memorized--knowledge without experience is usually of minimal benefit. But if you use the instruction set to write programs, it really shouldn't take too long before a program can just "flow" from your fingertips. Sure, you go back to reference material to verify instruction timing, etc. but you don't have to go the reference material to remember what instruction rotates the accumulator one bit to the left. Like any other language (computer or human), you eventually become fluent in it--then it's just a matter of using it optimally to generate your masterpiece.

I also will disagree with those that think example code should be tossed. I do agree you gain more by writing your own code, but I've found examples to be very useful to me. It helps me initially know that I'm going in the right direction. I don't depend on the code and, more than once, I've found errors in example code--but sometimes that can be even more useful. If you are able to detect the error in someone else's code, you must be well on your way to not only understanding the code in question, but understanding the logic that the author was trying to implement.

Those are my two cents, anyway.

Regards,
Craig Steiner