Google Releases The Android Open Accessory Toolkit For Adding Devices To Tablets And Phones


Google Releases The Android Open Accessory Toolkit For Adding Devices To Tablets And Phones

In this post-PC world, tablets and phones are starting to be our main devices. But what if we want to do something special with like like adding keyboards, mice, and game controllers. Google is working on a new project called the Android Open Accessory toolkit that will allow designers to use open source hardware interfaces like Arduino to connect multiple input devices to almost any Android system.

The Arduino boards will act as reference designs for manufacturers to base their future systems on and will not appear in most finished products. However, because Google is using Arduino, hobbyists and tinkerers can connect to Android devices with a bit of coding.

The first cool implementation comes with Android@Home, a system for controlling LED lights from an Android device. This unique – and fairly exciting system – will appear at the end of the year.

The program is completely open with no NDAs, fees, or approval process.

It’s like “made for iPod” but it’s Arduino and it’s open. This will obviously increase the amount of folks interested in Arduino 🙂 For some reason we usually are asked (by arduino skeptics) “when will Arduino go mainstream” ? – this might just be another data point to support more mainstreamy-ness.

A USB micro-controller board that is based on the Arduino Mega2560 and Circuits@Home USB Host Shield designs (now referred to as the ADK board), which you will later implement as an Android USB accessory. The ADK board provides input and output pins that you can implement through the use of attachments called “shields.” Custom firmware, written in C++, is installed on the board to define the board’s functionality and interaction with the attached shield and Android-powered device. The hardware design files for the board are located in hardware/ directory.

Not sure where to buy the hardware yet (?).

Android Open Accessory Development Kit

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  1. The hardware spec is completely open and available from here:

    Looks beyond my capabilities, but I’m sure the geniuses at adafruit can figure it out and create it. I’ll be waiting to send you my money for this! Please hurry…

  2. Now this is going to be a good for Android tablets and other devices. Open is the way to go.

  3. I know it says its based off of the Mega series, but will smaller boards such as the UNO be able to work too?

  4. I want an Android “iPod touch” (phone minus the phone) device to control my robot minions!

    Seriously, this is really cool for app developers and hobbyists alike. I wonder if it will work with existing Arduino hardware (firmware flash, for example)? I started looking at programming for Android devices, and it was a lot trickier than the iPhone programming I do for work, but with this, I better give it another shot.

  5. a minute ago I was torn between biting the bullet and getting an iPhone, or an android phone. Now I’m sold on android. Open Source FTW!

  6. Buy link:

    31500 Japanese yen = 390.0928 US dollars

  7. I was into Arduino before it was cool.

    j/k — it was always cool!

  8. David House has a good starting link, and that page links to as a ‘buy the hardware’ link. Not terribly useful if your Japanese is rusty, but from there you can get to where you can actually buy the thing, assuming you understand international shopping cart language, for about $390 US. Yeowch.

    Love the capcha, btw.

  9. Ah, I see I scrolled to hard on that page, presumably in my excitement. Price is still the same, but the shopping page is clearly there in English.

  10. $400 from the RT shop in Japan, yikes!

    Surely our Adafruit friends are working on a compatible shield right now.

    Surprisingly (to me at least), the Arduino ADK is the USB Host, the Android phone or tablet is the USB device. Apparently Android 3.1 (Ice Cream Sandwich) adds USB device mode, later this year.


  11. Agreed.. waiting for a more appropriately priced version.

    There does not seem to be anything about this board to account for the astronomical price point. It’s just a Mega with a few some useful components built in.

  12. Why the requirement for the USB device to be the host and supply charging current? Is it currently possible to have an Android device (or more specifically, phones) talk to (that is, passing data back and forth) external devices over USB now, without the requirement for the device to be the host?

  13. Why the requirement for the USB device to be the host and supply charging current? Is it currently possible to have an Android device (or more specifically, phones) talk to (that is, passing data back and forth) external devices over USB now, without the requirement for the device to be the host?

  14. The price is for both the Arduino-mega equivalent (with added USB-host capability) AND the multi-function (relay + servo + light + joystick + touch sensor + temperature, at least.) But still…

    Is there any word from anywhere about signing up additional manufacturers and distributors? Having it sold only from Japan would be less than ideal even if it were cheap…

    Any info on the Arduino distributor grapevine about the degree of involvement of the official Arduino team with this project?

  15. I downloaded the ADK, and took a peek at the schematics. It looks like the ADK board uses a FT232 chip and a ATMEGA1280. Does this mean the ADK board is actually based on the older Arduino MEGA and NOT the newer Mega 2560??

  16. Will the Android open accessory thing work with different versions of arduino? I’ve got an Uno board and would love to try something with my phone.

  17. I added support for ADK code to the standard library ->

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