How would I properly make an Arduino board support package that hadchanges tothe core files for a new board based on the ATMega1284p? Specifically, I would like to add attachInterrupt support for INT2. The other thing that would be nice is if I could add support for the secondary hardware UART. My understanding is that this involves adding files to a hardware subfolder in your sketchbook folder, but the detailed mechanics of that are not clear to me. Can anyone offer advice?
In Cosa all of this is already done for you and available out of the box: Cosa: An Object-Oriented Platform for Arduino programming - Libraries - Arduino Forum
Otherwise checkout the Mighty core.
Cheers!
Scroll down about 1/2 way down the page for links to the Mighty1284 files.
http://www.crossroadsfencing.com/BobuinoRev17/