This book explores how to use Assembly Language within your Arduino sketches, directly from the Arduino IDE, without any external tools. By learning to write low-level code, you’ll gain the ability to reduce sketch size, increase execution speed, and achieve precise timing control, especially useful for tasks like bit-banging communication protocols. It’s designed to be both educational and practical, helping developers and makers to reduce the size of their sketches, increase the speed of execution, and to get a much better understanding of how the Arduino hardware works. With a focus on clarity and hands-on examples, it’s ideal for developers and makers who want to push their Arduino projects further and gain deeper insight into microcontroller programming. What You'll Learn • How to code in Assembly for speed, code size and exact timings. • How to write libraries for use with Assembly (and C++ for some of the libraries). • How to interact with all the hardware features of the ATmega328P, from Assembly Language. • What to avoid and other pitfalls. Who Is This Book For Everyone with an interest in the Arduino boards based on the ATmega328P. All levels but a passing understanding of some programming languages would be helpful.