ADK 1.0 devices fail to work with Jelly Bean, why?

Question

Just connected the tried and true ADK accessory to Nexus 7 and Galaxy Nexus - and it failed to connect with "could not read device protocol version" message. Thought that the board died, connected to Nexus S with ICS - worked just fine. Worked on Galaxy Nexus before Jelly Bean upgrade as well, so hardware failure can be ruled out.

I've been watching ADK announcements pretty closely, but don't remember reading or hearing anything about this particular change, nor backward compatibility of Android devices supporting ADK 2.0.

Accessory Development Kit 2011 Guide says "Protocol version 1 is supported by Android 2.3.4 (API Level 10) and higher. Protocol version 2 is supported by Android 4.1 (API Level 16) and higher", it doesn't say that version 1 is not supported by 4.1, and it would be pretty bizarre to find that existing hardware would be abandoned just like that.

What am I missing here? Is this a bug or a feature?

Answer 1

The old ADK1 libraries released last year don't recognize the new AOA v2 protocol that JellyBean devices (Android 4.1 and up) speak. This was fixed in an updated ADK1 library release.

Go get the new ADK1 libraries:

• http://developer.android.com/tools/adk/adk.html (look for "release_20120606" or higher in the zip download)

Update your ADK libraries and upload your ADK1 sketch. Note that the new libraries have been updated to work with Arduino 1.0 and higher, so you will probably have to update your Arduino IDE as well.