Arduino is still (as of v1.0.5) packaged with an out-of-date version of WinAVR and AVRDUDE. This older version does not support the ATmega128RFA1.

The version of WinAVR in this directory (WinAVR-20100110) should be installed over the WinAVR included with Arduino, which is located in the Arduino\hardware\tools\avr directory. Follow these steps to update WinAVR:

1. Run the WinAVR-20100110-install.exe in this directory.
2. Cick "Run", Select your install Language, Click "Next", Click "I Agree" (unless you don't?), until you get to this the install location screen.
3. On the install location screen, click **Browse..**, and navigate to the *../hardware/tools/avr* directory wherever your Arduino install is (with the Arduino installer, this should be about where it is: 
4. Click next. On the next screen, make sure *Install files* and *Add Directories to PATH* are selected. *Install Programmers Notepad* is optional. 
5. Click *Next* and wait for the install to finish.

Add the Board Definitions File

The 128RFA1-DEV folder should be added to a hardware directory within your Arduino sketchbook. Normally the sketchbook will install to your documents/Arduino folder. If a hardware folder isn't already there, make it.


This directory contains a boards.txt file which defines the ATmega128RFA1 Dev Board, and adds a selectable option under the Tools > Board menu. When you open the Arduino ID (close and reopen if it's already open), this option should be added to the menu: