Similar to the MEGA 2560 and Uno, it features an Atmega8U2 programmed as a USB-to-serial converter.

For information on using the board with the Android OS, see Google's ADK documentation.

Schematic, Reference Design & Pin Mapping

• Arduino_ADK-Mega_2560-Rev2-reference-design.zip
• Arduino ADK_Mega_2560-schematic.pdf
• PinMap2560 page

The Arduino ADK can be powered via the USB connection or with an external power supply. The power source is selected automatically. External (non-USB) power can come either from an AC-to-DC adapter (wall-wart) or battery. The adapter can be connected by plugging a 2.1mm center-positive plug into the board's power jack. Leads from a battery can be inserted in the Gnd and Vin pin headers of the POWER connector.

NB: Because the ADK is a USB Host, the phone will attempt to draw power from it when it needs to charge. When the ADK is powered over USB, 500mA total is available for the phone and board.The external power regulator can supply up to 1500mA. 750mA is available for the phone and ADK board. An additional 750mA is allocated for any actuators and sensors attached to the board. A power supply must be capable of providing 1.5A to use this much current.

The board can operate on an external supply of 5.5 to 16 volts. If supplied with less than 7V, however, the 5V pin may supply less than five volts and the board may be unstable. If using more than 12V, the voltage regulator may overheat and damage the board. The recommended range is 7 to 12 volts.

The ADK has 256 KB of flash memory for storing code (of which 8 KB is used for the bootloader), 8 KB of SRAM and 4 KB of EEPROM (which can be read and written with the EEPROM library).

Each of the 50 digital pins on the ADK can be used as an input or output, using pinMode(), digitalWrite(), and digitalRead() functions. They operate at 5 volts. Each pin can provide or receive a maximum of 40 mA and has an internal pull-up resistor (disconnected by default) of 20-50 kOhms. In addition, some pins have specialized functions:

• Serial: 0 (RX) and 1 (TX); Serial 1: 19 (RX) and 18 (TX); Serial 2: 17 (RX) and 16 (TX); Serial 3: 15 (RX) and 14 (TX). Used to receive (RX) and transmit (TX) TTL serial data. Pins 0 and 1 are also connected to the corresponding pins of the ATmega8U2 USB-to-TTL Serial chip.
• External Interrupts: 2 (interrupt 0), 3 (interrupt 1), 18 (interrupt 5), 19 (interrupt 4), 20 (interrupt 3), and 21 (interrupt 2). These pins can be configured to trigger an interrupt on a low value, a rising or falling edge, or a change in value. See the attachInterrupt() function for details.
• PWM: 0 to 13. Provide 8-bit PWM output with the analogWrite() function.
• SPI: 50 (MISO), 51 (MOSI), 52 (SCK), 53 (SS). These pins support SPI communication using the SPI library. The SPI pins are also broken out on the ICSP header, which is physically compatible with the Uno, Duemilanove and Diecimila.
• USB Host: MAX3421E. The MAX3421E comunicate with Arduino with the SPI bus. So it uses the following pins:
  • Digital: 7 (RST), 50 (MISO), 51 (MOSI), 52 (SCK).
    NB:Please do not use Digital pin 7 as input or output because is used in the comunication with MAX3421E
  • Non broken out on headers: PJ3 (GP_MAX), PJ6 (INT_MAX), PH7 (SS).
• LED: 13. There is a built-in LED connected to digital pin 13. When the pin is HIGH value, the LED is on, when the pin is LOW, it's off.
• TWI: 20 (SDA) and 21 (SCL). Support TWI communication using the Wire library. Note that these pins are not in the same location as the TWI pins on the Duemilanove or Diecimila.

The Arduino ADK has a number of facilities for communicating with a computer, another Arduino, or other microcontrollers. The ATmega2560 provides four hardware UARTs for TTL (5V) serial communication. An ATmega8U2 on the board channels one of these over USB and provides a virtual com port to software on the computer (Windows machines will need a .inf file, but OSX and Linux machines will recognize the board as a COM port automatically. The Arduino software includes a serial monitor which allows simple textual data to be sent to and from the board. The RX and TX LEDs on the board will flash when data is being transmitted via the ATmega8U2 chip and USB connection to the computer (but not for serial communication on pins 0 and 1).

A SoftwareSerial library allows for serial communication on any of the ADK's digital pins.

The ATmega2560 also supports TWI and SPI communication. The Arduino software includes a Wire library to simplify use of the TWI bus; see the Wire library for details. For SPI communication, use the SPI library.

The USB host interface given by MAX3421E IC allows the ADK Arduino to connect and interact to any type of device that have a USB port. For example, allows you to interact with many types of phones, controlling Canon cameras, interfacing with keyboard, mouse and games controllers as Wiimote and PS3.

The Arduino ADK can be programmed with the Arduino software (download). For details, see the reference and tutorials.

The ATmega2560 on the Arduino ADK comes preburned with a bootloader (the same on Mega 2560) that allows you to upload new code to it without the use of an external hardware programmer. It communicates using the original STK500v2 protocol (reference, C header files).

You can also bypass the bootloader and program the microcontroller through the ICSP (In-Circuit Serial Programming) header; see these instructions for details.

The ATmega8U2 firmware source code is available in the Arduino repository. The ATmega8U2 is loaded with a DFU bootloader, which can be activated by connecting the solder jumper on the back of the board (near the map of Italy) and then resetting the 8U2. You can then use Atmel's FLIP software (Windows) or the DFU programmer (Mac OS X and Linux) to load a new firmware. Or you can use the ISP header with an external programmer (overwriting the DFU bootloader). See this user-contributed tutorial for more information.

With this board you need to change the boards.txt file in your Arduino directory (find it in: Arduino-00xx->hardware->arduino) with this updated version that include also the Mega ADK board: boards.txt

Windows users in order to get working the board need a .inf file for this specific product: Arduino_ADK.zip
For installation follow the same procedure on how install an UNO board on your computer.