В данных рекомендациях описывается, как использовать преимущества архитектуры AVR и инструментальных средств для более эффективного программирования на Си в отличие от других микроконтроллеров.

AVR Libc is a Free Software project whose goal is to provide a high quality C library for use with GCC on Atmel AVR microcontrollers.

If you're reading this tutorial, you probably have some interest in writing an extension for the PHP language. If not... well perhaps when we're done you'll have discovered an interest you didn't know existed!