Overview

The following three chapters are an exercise in miniaturization how small can a Web server get? I already know the answer: there is a server on the Web that claims to use only 256 bytes of read-only memory (ROM) for its TCP stack, but I can't help thinking that this must be a highly optimized chunk of assembly language, which is very difficult to adapt for any practical use. My objective is to create a miniature Web server in C that is still potentially useful, in that it can monitor and control real-world devices connected to the system's I/O lines.

There is little point in performing this exercise on the PC platform I've used in the previous chapters. I will have to switch to a smaller and cheaper system based on a single-chip computer (a microcontroller). The minimal resources of a microcontroller (ROM and RAM) will force you to look very carefully at the protocol-handling techniques already discussed and will challenge a lot of the comfortable assumptions I've been making over the past few chapters.

To do justice to the subject, it will take three chapters. In this chapter, I discuss the characteristics of microcontrollers and the techniques that can be used to miniaturize the TCP stack. In Chapter 10, I look at the hardware and TCP implementation, and in Chapter 11, I describe the Web server and the techniques used to insert dynamic data into its pages.

I'm also using these chapters as an opportunity to...