I've been working in the software business for over 30 years but until recently, hadn't been playing directly with Micro Processors. When I bought a Raspberry PI and then an Arduino, I'm afraid I got hooked. In my house I am surrounded by computers of all shapes, sizes and capacities … any one of them with orders of magnitude more power than any of these small devices … however, I still found myself fascinated.

When I stumbled across the ESP8266 earlier this year, it piqued my interest. I hadn't touched C programming in decades (I'm a Java man these days). As I started to read what was available in the way of documentation from the excellent community surrounding the device, I found that there were only small pockets of knowledge. The best source of information was (and still is) the official PDFs for the SDK from Espressif (the makers of the ESP8266) but even that is quite "light" on examples and background. As I studied the device, I started to make notes and my pages of notes continued to grow and grow.

This book is my collated and polished version of those notes. Rather than keep them to myself, I offer them to all of us in the ESP8266 community in the hope that they will be of some value. My plan is to continue to update this work as we all learn more and share what we find in the community forums. As such, I will re-release the work at regular intervals so please check back at the book's home page for the latest.

A separate book for the ESP32 is available here ... https://leanpub.com/kolban-ESP32