OS X communicating with an Adafruit Gemma

Background/Problem

I bought an Adafruit Gemma to make a LED enhanced vest for my dog to wear during the dark part of the year up here in northern Europe, but I could not get it to talk to my OS X. When connecting it, the red LED did not blink, but instead gave off a steady red light.

An Adafruit Gemma.

As with my Adafruit Trinket, I tried with multiple cables without success.

Solution

I got a cheap USB 2.0 hub and connected it to my Adafruit Gemma through that one, and immediately the red LED started to blink to indicate that the boot-loader was operational!

A PlexGear USB 2.0 hub.

While it never showed up as a PORT menu option in Arduino IDE, I could load sketches in the same way as I did with my Adafruit Trinket:

1. Made sure I had the programmer set to USBTinyISP
2. Loaded up the Blink example sketch
3. Clicked the Gemma's reset button
4. Clicked the 'Upload' button from Arduino IDE.

Tada!