Teensy is a complete USB-based microcontroller system, in a very small footprint, breadboard-friendly development board designed by Paul Stoffregen and PJRC. This book helps you to get started with Teensy development. The following is highlight topics: * Preparing development environment * Setting up Teensy * GPIO Programming * UART * PWM and analog input * Working with I2C * Working with SPI * mbed development for Teensy