Dec 19, 2019 · An Arduino core for ATmega8535, ATmega16, ATmega32, ATmega164, ATmega324, ATmega644 and ATmega1284, all running a Optiboot. Most Arduino UNO compatible libraries will work with this core. If not, it's fairly straight forward to port a library. This core requires at least Arduino IDE v1.6, where v1.8 ...

ATMEGA datasheet, cross reference, circuit and application notes in pdf format.