If you’re setting up the IDE for the first time, use this instructions:

Step 1

If you don’t want to modify an existing Arduino IDE install, you can simply download our ready-to-go and tested Flora/Gemma/Trinket-ified v1.05 right here:

Mac Arduino IDE v1.05 w/Trinket, Gemma, Flora Windows Arduino IDE v1.05 w/Trinket, Gemma, Flora

If you’re using Mac OS Mavericks you will need to update the setting to permit running Arduino IDE

  1. Go to your Security and Privacy Settings
  2. Click the Lock Icon and Login
  3. Change “Allow Apps Downloaded From”: to “Mac App Store and identified developers”

Step 2

Add ATtiny85 Support

http://learn.adafruit.com/system/assets/assets/000/010/777/original/trinkethardwaresupport.zip?1378321062

Unzip it and move the hardware folder from the zip file and place it into to your Arduino sketchbook folder. Your sketchbook folder is the folder where the Arduino IDE stores your sketches. This folder is automatically created by the IDE when you install it. If this is your first time using the Arduino IDE, it will be empty! Note: On Windows and Macintosh machines, the default name of the folder is “Arduino” and is located in your Documents folder.

Now you can start (or restart the the IDE) and check theTools->Board menu, you should see the three new entries for Trinket and Gemma:

Step 3

Updating avrdude.conf

The second step is to update the AVR chip program upload helper to be a little more patient with the ATtiny85 bootloader we have on the Gemma. We will update the description of the chip’s erase cycle to be longer, to avoid timeouts and errors.

Windows and Linux users can download the newavrdude.conf by clicking this link: http://learn.adafruit.com/system/assets/assets/000/010/769/original/avrdude.conf?1378221965

Mac users should download this version: http://learn.adafruit.com/system/assets/assets/000/010/823/original/avrdude.conf?1378680681

Now we will hunt for the original avrdude.conf file. If you are using a Mac, right-click on the Arduino application icon and select “Show Package Contents.” On Windows you will have to find the installation directory, which may be a folder on the Desktop or possibly in C:Program Files if you used the installer. Likewise in Linux it is where-ever you uncompressed the folder.

Now find the hardware/tools/avr/etc folder (on Macit’sContents/Resources/Java/hardware/tools/avr/etc), and inside you should see the avrdude.conf file. You can also use your operating system’s Now we will hunt for the original avrdude.conf file. If you are using a Mac, right-click on the Arduino application icon and select “Show Package Contents.” On Windows you will have to find the installation directory, which may be a folder on the Desktop or possibly in C:Program Files if you used the installer. Likewise in Linux it is where-ever you uncompressed the folder.

Now find the hardware/tools/avr/etc folder (on Mac it’sContents/Resources/Java/hardware/tools/avr/etc), and inside you should see the avrdude.conf file. You can also use your operating system’s find tool to locate it. tool to locate it.

Rename the old avrdude.conf to avrdude.bak and copy over the new avrdude.conf to the same folder

Step 3

Update ‘ld’ linker

There’s a bug in the ‘linker’ used by Arduino on Mac & Windows, where you can’t make sketches that are larger than 4K on the Attiny85. Since its really likely you’ll make sketches this large, we suggest replacing it. It’s a lot like replacing the avrdude.conf

On Windows: explore the Arduino folder and get to thehardwaretoolsavrbin subfolder, you’ll see a lot of files starting with avr-xxx.

On Mac: Explore the App and find Adafruit Arduino.app/Contents/Resources/Java/hardware/tools/avr/avr/bin

Download the ld for your operating system and replace the one you have now (thanks to TCWorld for this fix!)

Windows: http://learn.adafruit.com/system/assets/assets/000/010/983/original/WINDOWS_ld.zip?1379343097

Mac: http://learn.adafruit.com/system/assets/assets/000/010/981/original/MAC_ld.zip?1379343046

Now restart the Arduino IDE. You are done with setup!