AVR (Arduino) LibraryTriple-A: Alternative
Lightweight library for people using AVR Libc and Makefiles for their Atmel development. Work in progress and not really in usable state yet.
Macro implementations of digital_write(), digital_read(), analog_write() and analog_read() functions.
Redirects STDIN and STDOUT to UART so you can use printf() and friends for debugging.
Hardware SPI helpers.
Bitbanged shift_in() and shit_out() functions.
Hardware timer helpers.
Code for driving led matrices with MAX7219.