This book has been designed to teach you advanced programming techniques for the 6502 microprocessor in a systematic and progressive way. Developing a program involves devising a suitable algorithm and appropriate data structures, and then coding the algorithm. In the case of a microprocessor such as the 6502, the design of the algorithm and the data structures is generally constrained by three conditions:

1. The amount of memory available is often limited or must be minimized; i.e., the program must be terse.

2. The highest possible execution speed may be required. Efficient coding of the program into assembly level language instructions then becomes an essential consideration. In particular, the use of registers must be optimized.

3. The specific input/output design requires an understanding of the input and output chips and their programming.