Triple-A: Alternative AVR (Arduino) Library

Lightweight library for people using AVR Libc and Makefiles for their Atmel development. Work in progress and not really in usable state yet.

Pins

Macro implementations of digital_write(), digital_read(), analog_write() and analog_read() functions.

UART

Redirects STDIN and STDOUT to UART so you can use printf() and friends for debugging.

SPI

Hardware SPI helpers.

Shift

Bitbanged shift_in() and shit_out() functions.

Timer

Hardware timer helpers.

MAX7219

Code for driving led matrices with MAX7219.