Designing Embedded Systems with PIC Microcontrollers, 2nd Edition

CHAPTER 13. Smarter systems and the PIC 18F2420

In this book so far we have studied microcontrollers from the PIC 16 Series, large and small. While these are good microcontrollers, certain tensions and limitations have emerged. Some aspects of the hardware are limiting, for example the small size of the stack or the way all those interrupt sources have to share a single interrupt vector. As far as the instruction set is concerned, we recognise the value of the RISC approach. The absence of certain styles of instruction is, however, frustrating. Branch instructions, for example, have to be made out of a combination of skip and goto. Furthermore, the prospect of crafting major programs out of all those little Assembler instructions is becoming ...