La ADK es basada en la Mega 2560. Ademas lleva un circuito USB que permite a esta placa de comunicarse con los dispositivos USB, y suministrarle tambien alimentazion.

Las características adicionales que vienen con la versión R3 son:

• ATmega 16U2 en vez de 8U2 como convertidor USB serial.
• 1.0 pinout: añadido SDA y SCL pines para TWI comunicación colocada cerca al pine AREF y dos pasadores de otras nuevas colocadas cerca del pine RESET, el IOREF que permiten que los escudos para adaptarse a la tensión proporcionada por la junta directiva y el segundo un no conectado pin, que se reserva para usos futuros.
• REINICIO del circuito mas fuerte.

Especificaciones técnicas

microprocesador	ATmega2560
Tensión de funcionamiento	5 V
Voltaje de entrada (recomendado)	7-12V
Voltaje de entrada (limites)	6-20V
Digital I/O Pines	54 (de los cuales 14 proporcionan salida PWM)
Pines de entrada analógica	16
DC Corriente por I/O Pine	40 mA
DC Corriente por 3.3V Pine	50 mA
Memoria flash	256 KB di cui 8 KB de los cuales 8 KB utilizadas por bootloader
SRAM	8 KB
EEPROM	4 KB
Velocidad de reloj	16 MHz

Para informaciones sobre el uso de la placa con el sistema operativo Android, hecha un vistazo en (documentación de Google ADK), para mas informaciones sobre la placa puede ver la pagina Mega ADK En la sección Hardware.

Especificaciones técnicas

Microcontrolador	ATmega328
Tension de operación	5V
Tensión de entrada	2.5-12V
I/O digitales	14 (6 de lo cuales con salida PWM)
entradas analogicas	6
Corriente de salida para I/O Pin	40 mA
Corriente de salida para 3.3V Pin	500 mA (con sorgente a 1.5A)
Corriente de salida para 5V Pin	1000 mA (con sorgente a 1.5A)
Flash Memory	32 KB (of which 2 KB used by bootloader)
SRAM	2 KB
EEPROM	1 KB
Clock Speed	16 MHz
Modulo BT	2.1 WT11i-A-AI4

Para obtener una descripción más detallada sobre su placa usted debe visitar la página oficial Arduino Bluetooth page en la sección Hardware.

Power

The Arduino BT can be powered via the V+ and GND screw terminals. The board contains a DC-DC convector that allows it to be powered with as little as 2.5V, a maximum of 12V. Higher voltages or reversed polarity in the power supply can damage or destroy the board. The protection for reverse polarity connection is ONLY on the screw terminal. The power pins are as follows:

• +VIN. The input voltage to the Arduino board (i.e. the same as the V+ screw terminal). You can supply voltage through this pin, or, if supplying voltage via the screw terminals, access it through this pin. Warning: The protection for reverse polarity connection is ONLY on the screw terminal, do not attach negative voltages to this pin. It will damage the board.
• 5V. This pin outputs a regulated 5V from the regulator on the board. The board can be supplied with power either from the screw terminal (2.5V – 12V) or the VIN pin of the board (2.5V-12V). Supplying voltage via the 5V or 3.3V pins bypasses the regulator, and can damage your board. We don’t advise it.
• GND. Ground pins.

Memory

The ATmega328 has 32 KB of flash memory for storing code (of which 2 KB is used for the bootloader). It has 1 KB of SRAM and 512 bytes of EEPROM (which can be read and written with the EEPROM library).

Input and Output

Each of the 14 digital pins on the BT 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). Used to receive (RX) and transmit (TX) TTL serial data. These pins are connected to the corresponding pins of the Bluegiga WT11 module.
• External Interrupts: 2 and 3. 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: 3, 5, 6, 9, 10, and 11. Provide 8-bit PWM output with the analogWrite() function.
• SPI: 10 (SS), 11 (MOSI), 12 (MISO), 13 (SCK). These pins support SPI communication, which, although provided by the underlying hardware, is not currently included in the Arduino language.
• BT Reset: 7. Connected to the reset line of the Bluegiga WT11 module, which is active high.
• 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.

The BT has 6 analog inputs, each of which provide 10 bits of resolution (i.e. 1024 different values). By default they measure from ground to 5 volts, though is it possible to change the upper end of their range using the AREF pin and some low-level code. Additionally, some pins have specialized functionality:

• I²C: 4 (SDA) and 5 (SCL). Support I²C (TWI) communication using the Wire library (documentation on the Wiring website).

There are a couple of other pins on the board:

• AREF. Reference voltage for the analog inputs. Used with analogReference().

See also the mapping between Arduino pins and ATmega168/328 ports.

Bluetooth Communication

The Bluegiga WT11 module on the Arduino BT provides Bluetooth communication with computers, phones, and other Bluetooth devices. The WT11 communicates with the ATmega328 via serial (shared with the RX and TX pins on the board). It comes configured for 115200 baud communication. The module should be configurable and detectable by your operating system’s bluetooth drivers, which should then provide a virtual com port for use by other applications. The Arduino software includes a serial monitor which allows simple textual data to be sent to and from the Arduino board over this bluetooth connection. The board can also be reprogrammed using this same wireless connection. The WT11 is specially configured for use in the Arduino BT. Its name is set to ARDUINOBT and passcode to 12345. For details, see the complete initialization sketch.

Communication

The Arduino BT has a number of other facilities for communicating. The ATmega328’s UART TTL (5V) serial communication is available on digital pins 0 (RX) and 1 (TX) as well as being connected to the WT11 module. A SoftwareSerial library allows for serial communication on any of the BT’s digital pins. The ATmega328 also supports I2C (TWI) and SPI communication. The Arduino software includes a Wire library to simplify use of the I2C bus; see the documentation on the Wiring website for details. To use the SPI communication, please see theATmega328 datasheet.

Programming

The Arduino BT can be programmed with the Arduino software (download). For details, see the reference and tutorials. The ATmega328 on the Arduino BT comes preburned with a bootloader that allows you to upload new code to it without the use of an external hardware programmer. It communicates using the original STK500 protocol (reference, C header files). You can also bypass the bootloader and program the ATmega328 through the ICSP (In-Circuit Serial Programming) header; see these instructions for details.

Physical Characteristics

The maximum length and width of the BT are approximately 3.2 and 2.1 inches respectively. Three screw holes allow the board to be attached to a surface or case. Note that the distance between digital pins 7 and 8 is 160 mil (0.16″), not an even multiple of the 100 mil spacing of the other pins.

El Arduino Esplora puede emular un ratón o un teclado, te permite crear tu propio controlador de software para música, herramientas 3D, o incluso un procesador de textos. El Arduino Esplora viene ya pre-programado con una secuencia de instrucciones de juego, así que tan pronto como lo conectes a tu ordenador puedes comenzar a jugar de inmediato. Para más detalle por favor visita arduino.cc/esplora.

Detalles tecnicos

Microcontroller	ATmega32u4
Operating Voltage	5V
Flash Memory	32 KB of which 4 KB used by bootloader
SRAM	2.5 KB
EEPROM	1 KB
Clock Speed	16 MHz

Lleva incluido el cable MICRO USB.

The Arduino Esplora is a microcontroller board derived from the Arduino Leonardo. The Esplora differs from all preceding Arduino boards in that it provides a number of built-in, ready-to-use setof onboard sensors for interaction. It’s designed for people who want to get up and running with Arduino without having to learn about the electronics first. For a step-by-step introduction to the Esplora, check out the Getting Started with Esplora guide.

The Esplora has onboard sound and light outputs, and several input sensors, including a joystick, a slider, a temperature sensor, an accelerometer, a microphone, and a light sensor. It also has the potential to expand its capabilities with two Tinkerkit input and output connectors, and a socket for a color TFT LCD screen.

Like the Leonardo board, the Esplora uses an Atmega32U4 AVR microcontroller with 16 MHz crystal oscillator and a micro USB connection capable of acting as a USB client device, like a mouse or a keyboard.

In the upper left corner of the board there is a reset pushbutton, that you can use to restart the board. There are four status LEDS :

• ON [green] indicates whether the board is receiving power supply
• L [yellow] connected directly to the microcontroller, accessible through pin 13
• RX and TX [yellow] indicates the data being transmitted or received over the USB communication

The board contains everything needed to support the microcontroller; simply connect it to a computer with a USB cable to get started.

Schematic & Reference Design

EAGLE files: Attach:arduino-esplora-reference-design.zip
Schematic: Attach:arduino-esplora-schematic.pdf

Memory

The ATmega32u4 has 32 KB (with 4 KB used for the bootloader). It also has 2.5 KB of SRAM and 1 KB of EEPROM (which can be read and written with the EEPROM library).

Input and Output:

The design of the Esplora board recalls traditional gamepad design with an analog joystick on the left and four pushbuttons on the right.

The Esplora has the following on-board inputs and outputs :

• Analog joystick with central push-button two axis (X and Y) and a center pushbutton.
• 4 push-buttons laid out in a diamond pattern.
• Linear potentiometer slider near the bottom of the board.
• Microphone for getting the loudness (amplitude) of the surrounding environment.
• Light sensor for getting the brightness.
• Temperature sensor reads the ambient temperature
• Three-axis accelerometer measures the board’s relation to gravity on three axes (X, Y, and Z)
• Buzzer can produce square-waves.
• RGB led bright LED with Red Green and Blue elements for color mixing.
• 2 TinkerKit Inputs to connect the TinkerKit sensor modules with the 3-pin connectors.
• 2 TinkerKit Outputs to connect the TinkerKit actuator modules with the 3-pin connectors.
• TFT display connector connector for an optional color LCD screen, SD card, or other devices that use the SPI protocol.

In order to utilize the total number of available sensors, the board uses an analog multiplexer. This means a single analog input of the microcontroller is shared among all the input channels (except the 3-axis accelerometer). Four additional microcontroller pins choose which channel to read.

Communication

The Leonardo the Esplora has a number of facilities for communicating with a computer, another Arduino, or other microcontrollers. The ATmega32U4 provides serial (CDC) communication over USB and appears as a virtual com port to software on the computer. The chip also acts as a full speed USB 2.0 device, using standard USB COM drivers. On Windows, a .inf file is required. The Arduino software includes a serial monitor which allows simple textual data to be sent to and from the Arduino board. The RX and TX LEDs on the board will flash when data is being transmitted via the USB connection to the computer.

The ATmega32U4 also supports SPI communication, that can be accessed through the SPI library.

The Esplora can appear as a generic keyboard and mouse, and can be programmed to control these input devices using theKeyboard and Mouse libraries.

Programming

The Esplora can be programmed with the Arduino software (download). Select «Arduino Esplora» from the Tools > Board menu. For details, see the getting started page.

The ATmega32U4 on the Arduino Esplora comes preburned with a bootloader that allows you to upload new code to it without the use of an external hardware programmer. It communicates using the AVR109 protocol.

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

Esplora Library

To facilitate writing sketches for the Esplora, there is a dedicated library that contains methods for reading the sensors and writing to the outputs on-board.

The library offers high level methods which provide pre-processed data, like degrees Fahrenheit or Celsius from the temperature sensor. It also enables easy access to the outputs, like writing values to the RGB LED.

Visit the Esplora library reference page to see the complete documentation of the library and examples.

Automatic (Software) Reset and Bootloader Initiation

Rather than requiring a physical press of the reset button before an upload, the Esplora is designed in a way that allows it to be reset by software running on a connected computer. The reset is triggered when the Esplora’s virtual (CDC) serial / COM port is opened at 1200 baud and then closed. When this happens, the processor will reset, breaking the USB connection to the computer (meaning that the virtual serial / COM port will disappear). After the processor resets, the bootloader starts, remaining active for about 8 seconds. The bootloader can also be initiated by pressing the reset button on the Esplora. Note that when the board first powers up, it will jump straight to the user sketch, if present, rather than initiating the bootloader.

Because of the way the Esplora handles reset it’s best to let the Arduino software try to initiate the reset before uploading, especially if you are in the habit of pressing the reset button before uploading on other boards. If the software can’t reset the board you can always start the bootloader by pressing the reset button on the board.

USB Overcurrent Protection

The Esplora has a resettable polyfuse that protects your computer’s USB ports from shorts and overcurrent. Although most computers provide their own internal protection, the fuse provides an extra layer of protection. If more than 500 mA is applied to the USB port, the fuse will automatically break the connection until the short or overload is removed.

Physical Characteristics

The maximum length and width of the Esplora PCB are 6.5 and 2.4 inches respectively, with the USB and TinkerKitconnectors extending beyond the latter dimension. Four screw holes allow the board to be attached to a surface or case.

The Due has two usb connectors, the one with the micro-usb AB connector is the native one capable to act as an USB host, that means you can connect compatible external usb peripherals to the board, such as mouse, keyboards, smartphones. While the other USB port with the type B connector is intended for debugging purposes. If you want to give a closer look to this board we advise you to visit the officialArduino Due page in the Products Section.

Technical Specifications

Microcontroller	AT91SAM3X8E
Operating Voltage	3.3V
Input Voltage (recommended)	7-12V
Input Voltage (limits)	6-20V
Digital I/O Pins	54 (of which 12 provide PWM output)
Analog Input Pins	12
Analog Outputs Pins	2 (DAC)
Total DC Output Current on all I/O lines	130 mA
DC Current for 3.3V Pin	800 mA
DC Current for 5V Pin	800 mA
SRAM	96 KB (64 + 32 KB)
Clock Speed	84 MHz

If you want to give a closer look to this board we advise you to visit the officialArduino Due page in the Products Section.

A separate power-over-Ethernet (PoE) module can be soldered to the board to provide power from a conventional twisted pair Category 5 Ethernet cable. It is IEEE802.3af compliant, and works with all compliant PoE injectors currently available. Additional features coming with the R3 version are:

• 1.0 pinout: added SDA and SCL pins for TWI communication placed near to the AREF pin and two other new pins placed near to the RESET pin, the IOREF that allow the shields to adapt to the voltage provided from the board and the second one is a not connected pin, that is reserved for future purposes.
• stronger RESET circuit.

Technical Specifications

Microcontroller	ATmega328
Operating Voltage	5V
Input Voltage (recommended)	7-12V
Input Voltage (limits)	6-20V
Digital I/O Pins	14 (of which 4 provide PWM output)

Analog Input Pins	6
DC Current per I/O Pin	40 mA
DC Current for 3.3V Pin	50 mA
Flash Memory	32 KB (ATmega328) of which 0.5 KB used by bootloader
SRAM	2 KB (ATmega328)
EEPROM	1 KB (ATmega328)
Clock Speed	16 MHz
W5100 TCP/IP Embedded Ethernet Controller
Power Over Ethernet ready Magnetic Jack
Micro SD card, with active voltage translators

Arduino Pins reserved

• 10 to 13 used for SPI
• 4 used for SD card
• 2 W5100 interrupt (when bridged)

Arduino Ethernet Official Page

The Leonardo differs from all preceding boards in that the ATmega32u4 has built-in USB communication, eliminating the need for a secondary processor. This allows the Leonardo to appear to a connected computer as a mouse and keyboard, in addition to a virtual (CDC) serial / COM port. It also has other implications for the behavior of the board; these are detailed on the getting started page. This version of the Leonardo comes assembled.

Summary

Microcontroller	ATmega32u4
Operating Voltage	5V
Input Voltage (recommended)	7-12V
Input Voltage (limits)	6-20V
Digital I/O Pins	20
PWM Channels	7
Analog Input Channels	12
DC Current per I/O Pin	40 mA
DC Current for 3.3V Pin	50 mA
Flash Memory	32 KB (ATmega32u4) of which 4 KB used by bootloader
SRAM	2.5 KB (ATmega32u4)
EEPROM	1 KB (ATmega32u4)
Clock Speed	16 MHz

The Mega 2560 is an update to the Arduino Mega, which it replaces. Additional features coming with the R3 version are:

• ATmega16U2 instead 8U2 as USB-to-Serial converter.
• 1.0 pinout: added SDA and SCL pins for TWI communication placed near to the AREF pin and two other new pins placed near to the RESET pin, the IOREF that allow the shields to adapt to the voltage provided from the board and the second one is a not connected pin, that is reserved for future purposes.
• stronger RESET circuit.

Technical Specifications

Microcontroller	ATmega2560
Operating Voltage	5V
Input Voltage (recommended)	7-12V
Input Voltage (limits)	6-20V
Digital I/O Pins	54 (of which 14 provide PWM output)
Analog Input Pins	16
DC Current per I/O Pin	40 mA
DC Current for 3.3V Pin	50 mA
Flash Memory	256 KB of which 8 KB used by bootloader
SRAM	8 KB
EEPROM	4 KB
Clock Speed	16 MHz

Since the Nano is automatically sense and switch to the higher potential source of power, there is no need for the power select jumper. The Arduino Nano is a small, complete, and breadboard-friendly board based on the ATmega328 (Arduino Nano 3.0) orATmega168 (Arduino Nano 2.x). It has more or less the same functionality of the Arduino Duemilanove, but in a different package. It lacks only a DC power jack, and works with a Mini-B USB cable instead of a standard one. The Nano was designed and is being produced by Gravitech.

Schematic and Design

Arduino Nano 3.0 (ATmega328): schematic, Eagle files. Operating Voltage (logic level)5 VInput Voltage (recommended)7-12 VInput Voltage (limits)6-20 VDigital I/O Pins14 (of which 6 provide PWM output)Analog Input Pins8DC Current per I/O Pin40 mAFlash Memory16 KB (ATmega168) or 32 KB (ATmega328) of which 2 KB used by bootloaderSRAM1 KB (ATmega168) or 2 KB (ATmega328)EEPROM512 bytes (ATmega168) or 1 KB (ATmega328)Clock Speed16 MHzDimensions0.73″ x 1.70″  

The Uno differs from all preceding boards in that it does not use the FTDI USB-to-serial driver chip. Instead, it features the Atmega16U2 (Atmega8U2 up to version R2) programmed as a USB-to-serial converter. Revision 2 of the Uno board has a resistor pulling the 8U2 HWB line to ground, making it easier to put into . Revision 3 of the board has the following new features:

• 1.0 pinout: added SDA and SCL pins that are near to the AREF pin and two other new pins placed near to the RESET pin, the IOREF that allow the shields to adapt to the voltage provided from the board. In future, shields will be compatible both with the board that use the AVR, which operate with 5V and with the Arduino Due that operate with 3.3V. The second one is a not connected pin, that is reserved for future purposes.
• Stronger RESET circuit.
• Atmega 16U2 replace the 8U2.

«Uno» means one in Italian and is named to mark the upcoming release of Arduino 1.0. The Uno and version 1.0 will be the reference versions of Arduino, moving forward. The Uno is the latest in a series of USB Arduino boards, and the reference model for the Arduino platform; for a comparison with previous versions, see the index of Arduino boards?.

Summary

Microcontroller	ATmega328
Operating Voltage	5V
Input Voltage (recommended)	7-12V
Input Voltage (limits)	6-20V
Digital I/O Pins	14 (of which 6 provide PWM output)
Analog Input Pins	6
DC Current per I/O Pin	40 mA
DC Current for 3.3V Pin	50 mA
Flash Memory	32 KB (ATmega328) of which 0.5 KB used by bootloader
SRAM	2 KB (ATmega328)
EEPROM	1 KB (ATmega328)
Clock Speed	16 MHz

Additional features coming with the R3 version are:

• ATmega16U2 instead 8U2 as USB-to-Serial converter.
• 1.0 pinout: added SDA and SCL pins for TWI communication placed near to the AREF pin and two other new pins placed near to the RESET pin, the IOREF that allow the shields to adapt to the voltage provided from the board and the second one is a not connected pin, that is reserved for future purposes.
• stronger RESET circuit.

«Uno» means «One» in Italian and is named to mark the upcoming release of Arduino 1.0. The Uno and version 1.0 will be the reference versions of Arduino, moving forward. The Uno is the latest in a series of USB Arduino boards, and the reference model for the Arduino platform; for a comparison with previous versions, see theindex of Arduino boards.

Technical Specifications

Microcontroller	ATmega328
Operating Voltage	5V
Supply Voltage (recommended)	7-12V
Maximum supply voltage (not recommended)	20V
Digital I/O Pins	14 (of which 6 provide PWM output)
Analog Input Pins	6
DC Current per I/O Pin	40 mA
DC Current for 3.3V Pin	50 mA
Flash Memory	32 KB (ATmega328) of which 0.5 KB used by bootloader
SRAM	2 KB (ATmega328)
EEPROM	1 KB (ATmega328)
Clock Speed	16 MHz

Control Board Summary

Microcontroller	ATmega32u4
Operating Voltage	5V
Input Voltage	5V through flat cable
Digital I/O Pins	5
PWM Channels	6
Analog Input Channels	4 (of the Digital I/O pins)
Analog Input Channels (multiplexed)	8
DC Current per I/O Pin	40 mA
Flash Memory	32 KB (ATmega32u4) of which 4 KB used by bootloader
SRAM	2.5 KB (ATmega32u4)
EEPROM (internal)	1 KB (ATmega32u4)
EEPROM (external)	512 Kbit (I2C)
Clock Speed	16 MHz
Keypad	5 keys
Knob	potentiomenter attached to analog pin
Full color LCD	over SPI communication
SD card reader	for FAT16 formatted cards
Speaker	8 Ohm
Digital Compass	provides deviation from the geographical north in degrees
I2C soldering ports	3
Prototyping areas	4

Motor Board Summary

Microcontroller	ATmega32u4
Operating Voltage	5V
Input Voltage	9V to battery charger
AA battery slot	4 alkaline or NiMh rechargeable batteries
Digital I/O Pins	4
PWM Channels	1
Analog Input Channles	4 (same as the Digital I/O pins)
DC Current per I/O Pin	40 mA
DC-DC converter	generates 5V to power up the whole robot
Flash Memory	32 KB (ATmega32u4) of which 4 KB used by bootloader
SRAM	2.5 KB (ATmega32u4)
EEPROM	1 KB (ATmega32u4)
Clock Speed	16 MHz
Trimmer	for movement calibration
IR line following sensors	5
I2C soldering ports	1
Prototyping areas	2

Schematic & Reference Design

EAGLE files for control and motor boards: arduino-robot-reference-design.zip

Power

The Arduino Robot can be powered via the USB connection or with 4 AA batteries. The power source is selected automatically. The battery holder holds 4 rechargeable NiMh AA batteries. NB : Do not use non-rechargeable batteries with the robot For safety purposes, the motors are disabled when the robot is powered from the USB connection. The robot has an on-board battery charger that requires 9V external power coming from an AC-to-DC adapter (wall-wart). The adapter can be connected by plugging a 2.1mm center-positive plug into the Motor Board’s power jack. The charger will not operate if powered by USB. The Control Board is powered by the power supply on the Motor Board.

Memory

The ATmega32u4 has 32 KB (with 4 KB used for the bootloader). It also has 2.5 KB of SRAM and 1 KB of EEPROM (which can be read and written with the EEPROM library). The Control Board has an extra 512 Kbit EEPROM that can be accessed via I2C. There is an external SD card reader attached to the GTFT screen that can be accessed by the Control Board’s processor for additional storage.

Input and Output

The Robot comes with a series of pre-soldered connectors. There are a number of additional spots for you to install additional parts if needed. All the connectors are labelled on the boards and mapped to named ports through the Robot library allowing access to standard Arduino functions. Each pin can provide or receive a maximum of 40mA at 5V. Some pins have specialized functions :

• Control Board TK0 to TK7: these pins are multiplexed to a single analog pin on theControl Board’s microprocessor. They can be used as analog inputs for sensors like distance sensors, analog ultrasound sensors, or mechanical switches to detect collisions.
• Control Board TKD0 to TKD5: these are digital I/O pins directly connected to the processor, addressed usingRobot.digitalRead() and Robot.digitalWrite) functions. Pins TKD0 to TKD3 can also be used as analog inputs withRobot.analogRead() Note: if you have one of the first generation robots, you will see that the TKD* pins are named TDK* on the Robot’s silkscreen. TKD* is the proper name for them and is how we address them on the software.

• Motor Board TK1 to TK4: these pins are named in software as B_TK1 to B_TK4, they can be digital or analog input pins, and support Robot.digitalRead(), Robot.digitalWrite) and Robot.analogRead().

• Serial Communication: The boards communicate with each other using the processors’ serial port. A 10-pin connector connects both boards carries the serial communication, as well as power and additional information like the battery’s current charge.
• Control Board SPI: SPI is used to control the GTFT and SD card. If you want to flash the processor using an external programmer, you need to disconnect the screen first
• Control Board LEDs: the Control Board has three on-board LEDs. One indicates the board is powered (PWR). The other two indicate communication over the USB port (LED1/RX and TX). LED1 is also accessible via software.
• Both boards have I2C connectors available: 3 on the Control Board and 1 on the Motor Board.

Control Board Pin Mapping

ARDUINO LEONARDO	ARDUINO ROBOT CONTROL	ATMEGA 32U4	FUNCTION	REGISTER
D0	RX	PD2	RX	RXD1/INT2
D1	TX	PD3	TX	TXD1/INT3
D2	SDA	PD1	SDA	SDA/INT1
D3#	SCL	PD0	PWM8/SCL	OC0B/SCL/INT0
D4	MUX_IN A6	PD4		ADC8
D5#	BUZZ	PC6	???	OC3A/#OC4A
D6#	MUXA/TKD4 A7	PD7	FastPWM	#OC4D/ADC10
D7	RST_LCD	PE6		INT6/AIN0
D8	CARD_CS A8	PB4		ADC11/PCINT4
D9#	LCD_CS A9	PB5	PWM16	OC1A/#OC4B/ADC12/PCINT5
D10#	DC_LCD A10	PB6	PWM16	OC1B/0c4B/ADC13/PCINT6
D11#	MUXB	PB7	PWM8/16	0C0A/OC1C/#RTS/PCINT7
D12	MUXC/TKD5 A11	PD6		T1/#OC4D/ADC9
D13#	MUXD	PC7	PWM10	CLK0/OC4A
A0	KEY D18	PF7		ADC7
A1	TKD0 D19	PF6		ADC6
A2	TKD1 D20	PF5		ADC5
A3	TKD2 D21	PF4		ADC4
A4	TKD3 D22	PF1		ADC1
A5	POT D23	PF0		ADC0
MISO	MISO D14	PB3		MISO,PCINT3
SCK	SCK D15	PB1		SCK,PCINT1
MOSI	MOSI D16	PB2		MOSI,PCINT2
SS	RX_LED D17	PB0		RXLED,SS/PCINT0
TXLED	TX_LED	PD5
HWB		PE2		HWB

Motor Board Pin Mapping

ARDUINO LEONARDO	ARDUINO ROBOT CONTROL	ATMEGA 32U4	FUNCTION	REGISTER
D0	RX	PD2	RX	RXD1/INT2
D1	TX	PD3	TX	TXD1/INT3
D2	SDA	PD1	SDA	SDA/INT1
D3#	SCL	PD0	PWM8/SCL	OC0B/SCL/INT0
D4	TK3 A6	PD4		ADC8
D5#	INA2	PC6	???	OC3A/#OC4A
D6#	INA1 A7	PD7	FastPWM	#OC4D/ADC10
D7	MUXA	PE6		INT6/AIN0
D8	MUXB A8	PB4		ADC11/PCINT4
D9#	INB2 A9	PB5	PWM16	OC1A/#OC4B/ADC12/PCINT5
D10#	INB1 A10	PB6	PWM16	OC1B/0c4B/ADC13/PCINT6
D11#	MUXC	PB7	PWM8/16	0C0A/OC1C/#RTS/PCINT7
D12	TK4 A11	PD6		T1/#OC4D/ADC9
D13#	MUXI	PC7	PWM10	CLK0/OC4A
A0	TK1 D18	PF7		ADC7
A1	TK2 D19	PF6		ADC6
A2	MUX_IN D20	PF5		ADC5
A3	TRIM D21	PF4		ADC4
A4	SENSE_A D22	PF1		ADC1
A5	SENSE_B D23	PF0		ADC0
MISO	MISO D14	PB3		MISO,PCINT3
SCK	SCK D15	PB1		SCK,PCINT1
MOSI	MOSI D16	PB2		MOSI,PCINT2
SS	RX_LED D17	PB0		RXLED,SS/PCINT0
TXLED	TX_LED	PD5
HWB		PE2		HWB

Communication

The Robot has a number of facilities for communicating with a computer, another Arduino, or other microcontrollers. TheATmega32U4 provides UART TTL (5V) serial communication, which is available on digital the 10-pin board-to-board connector. The 32U4 also allows for serial (CDC) communication over USB and appears as a virtual com port to software on the computer. The chip also acts as a full speed USB 2.0 device, using standard USB COM drivers. On Windows, a .inf file is required. The Arduino software includes a serial monitor which allows simple textual data to be sent to and from the Robot board. The RX (LED1) and TX LEDs on the board will flash when data is being transmitted via the USB connection to the computer (but not for serial communication between boards). Each one of the boards has a separate USB product identifier and will show up as different ports on you IDE. Make sure you choose the right one when programming. The ATmega32U4 also supports I2C (TWI) and SPI communication. The Arduino software includes a Wire library to simplify use of the I2C bus; see the documentation for details. For SPI communication, use the SPI library.

Programming

The Robot can be programmed with the Arduino software (download). Select «Arduino Robot Control Board» or «Arduino Robot Motor Board» from the Tools > Board menu. For details, see the getting started page and tutorials. The ATmega32U4 processors on the Arduino Robot come preburned with a bootloader that allows you to upload new code to it without the use of an external hardware programmer. It communicates using the AVR109 protocol. You can bypass the bootloader and program the microcontroller through the ICSP (In-Circuit Serial Programming) header; see these instructions for details.

Automatic (Software) Reset and Bootloader Initiation

Rather than requiring a physical press of the reset button before an upload, the Robot is designed in a way that allows it to be reset by software running on a connected computer. The reset is triggered when the Robot’s virtual (CDC) serial / COM port is opened at 1200 baud and then closed. When this happens, the processor will reset, breaking the USB connection to the computer (meaning that the virtual serial / COM port will disappear). After the processor resets, the bootloader starts, remaining active for about 8 seconds. The bootloader can also be initiated by double-pressing the reset button on the Robot. Note that when the board first powers up, it will jump straight to the user sketch, if present, rather than initiating the bootloader. Because of the way the Robot handles reset it’s best to let the Arduino software try to initiate the reset before uploading, especially if you are in the habit of pressing the reset button before uploading on other boards. If the software can’t reset the board you can always start the bootloader by double-pressing the reset button on the board. A single press on the reset will restart the user sketch, a double press will initiate the bootloader.

USB Overcurrent Protection

Both of the Robot boards have a resettable polyfuse that protects your computer’s USB ports from shorts and overcurrent. Although most computers provide their own internal protection, the fuse provides an extra layer of protection. If more than 500 mA is applied to the USB port, the fuse will automatically break the connection until the short or overload is removed.

Physical Characteristics

The Robot is 19cm in diameter. Including wheels, GTFT screen and other connectors it can be up to 10cm tall.

To Learn More

See also: getting started with the Arduino Robot and the Robot’s library pages.

Summary

Because the Yún has two processors, the summary section shows the characteristics of each one in two separate tables.

AVR Arduino microcontroller
Microcontroller	ATmega32u4
Operating Voltage	5V
Input Voltage	5V
Digital I/O Pins	20
PWM Channels	7
Analog Input Channels	12
DC Current per I/O Pin	40 mA
DC Current for 3.3V Pin	50 mA
Flash Memory	32 KB (of which 4 KB used by bootloader)
SRAM	2.5 KB
EEPROM	1 KB
Clock Speed	16 MHz
Linux microprocessor
Processor	Atheros AR9331
Architecture	MIPS @400MHz
Operating Voltage	3.3V
Ethernet	IEEE 802.3 10/100Mbit/s
WiFi	IEEE 802.11b/g/n
USB Type-A	2.0 Host/Device
Card Reader	Micro-SD only
RAM	64 MB DDR2
Flash Memory	32 MB
PoE compatible 802.3af card support

Schematic & Reference Design

Schematic: arduino-Yun-schematic.pdf

Power

It is recommended to power the board via the micro-USB connection with 5VDC.

If you are powering the board though the Vin pin, you must supply a regulated 5VDC. There is no on-board voltage regulator for higher voltages, which will damage the board.

The Yún is also compatible with PoE power supply but in order to use this feature you need to mount a PoE module on the board or buy a preassembled one.

The power pins are as follows:

• VIN. The input voltage to the Arduino board. Unlike other Arduino boards, if you are going to provide power to the board through this pin, you must provide a regulated 5V.
• 5V. The power supply used to power the microcontrollers and other components on the board. This can come either from VIN or be supplied by USB.
• 3V3. A 3.3 volt supply generated by the on-board regulator. Maximum current draw is 50 mA.
• GND. Ground pins.
• IOREF. The voltage at which the i/o pins of the board are operating (i.e. VCC for the board). This is 5V on the Yún.

Memory

The ATmega32u4 has 32 KB (with 4 KB used for the bootloader). It also has 2.5 KB of SRAM and 1 KB of EEPROM (which can be read and written with the EEPROM library).

The memory on the AR9331 is not embedded inside the processor. The RAM and the storage memory are externally connected. The Yún has 64 MB of DDR2 RAM and 16 MB of flash memory. The flash memory is preloaded in factory with a Linux distribution based on OpenWRT called Linino. You can change the content of the factory image, such as when you install a program or when you change a configuration file. You can return to the factory configuration by pressing the «WLAN RST» button for 30 seconds.

Input and Output

It is not possible to access the I/O pins of the Atheros AR9331. All I/O lines are tied to the 32U4.

Each of the 20 digital i/o pins on the Yún can be used as an input or output, using pinMode(), digitalWrite(), anddigitalRead() 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). Used to receive (RX) and transmit (TX) TTL serial data using the ATmega32U4 hardware serial capability. Note that on the Yún, the Serial class refers to USB (CDC) communication; for TTL serial on pins 0 and 1, use the Serial1 class. The hardware serials of the ATmega32U4 and the AR9331 on the Yún are connected together and are used to communicate between the two processors. As is common in Linux systems, on the serial port of the AR9331 is exposed the console for access to the system, this means that you can access to the programs and tools offered by Linux from your sketch.
• TWI: 2 (SDA) and 3 (SCL). Support TWI communication using the Wire library.
• External Interrupts: 3 (interrupt 0), 2 (interrupt 1), 0 (interrupt 2), 1 (interrupt 3) and 7 (interrupt 4). 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. Is not recommended to use pins 0 and 1 as interrupts because they are the also the hardware serial port used to talk with the Linux processor. Pin 7 is connected to the AR9331 processor and it may be used as handshake signal in future. Is recommended to be careful of possible conflicts if you intend to use it as interrupt.
• PWM: 3, 5, 6, 9, 10, 11, and 13. Provide 8-bit PWM output with the analogWrite() function.
• SPI: on the ICSP header. These pins support SPI communication using the SPI library. Note that the SPI pins are not connected to any of the digital I/O pins as they are on the Uno, They are only available on the ICSP connector. This means that if you have a shield that uses SPI, but does NOT have a 6-pin ICSP connector that connects to the Yún’s 6-pin ICSP header, the shield will not work.

The SPI pins are also connected to the AR9331 gpio pins, where it has been implemented in software the SPI interface. This means that the ATMega32u4 and the AR9331 can also communicate using the SPI protocol.

• 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.
• There are several other status LEDs on the Yún, indicating power, WLAN connection, WAN connection and USB.

• Analog Inputs: A0 – A5, A6 – A11 (on digital pins 4, 6, 8, 9, 10, and 12). The Yún has 12 analog inputs, labeled A0 through A11, all of which can also be used as digital i/o. Pins A0-A5 appear in the same locations as on the Uno; inputs A6-A11 are on digital i/o pins 4, 6, 8, 9, 10, and 12 respectively. Each analog input provide 10 bits of resolution (i.e. 1024 different values). By default the analog inputs measure from ground to 5 volts, though is it possible to change the upper end of their range using the AREF pin and the analogReference() function.
• AREF. Reference voltage for the analog inputs. Used with analogReference().

There are 3 reset buttons with different functions on the board:

• Yún RST. Bring this line LOW to reset the AR9331 microprocessor. Resetting the AR9331 will cause the reboot of the linux system. All the data stored in RAM will be lost and all the programs that are running will be terminated.

• 32U4 RST. Bring this line LOW to reset the ATmega32U4 microcontroller. Typically used to add a reset button to shields which block the one on the board.
• WLAN RST. This button has a double feature. Primarly serves to restore the WiFi to the factory configuration. The factory configuration consist to put the WiFi of the Yún in access point mode (AP) and assign to it the default IP address that is 192.168.240.1, in this condition you can connect with your computer to the a WiFi network that appear with the SSID name «Arduino Yun-XXXXXXXXXXXX», where the twelve ‘X’ are the MAC address of your Yún. Once connected you can reach the web panel of the Yún with a browser at the 192.168.240.1 or «http://arduino.local» address. Note that restoring the WiFi configuration will cause the reboot of the linux environment. To restore your WiFi configuration you have to press and hold the WLAN RST button for 5 seconds. When you press the button the WLAN blue LED will start to blink and will keep still blinking when you release the button after 5 seconds indicating that the WiFi restore procedure has been recorded. The second function of the WLAN RST button is torestore the linux image to the default factory image. To restore the linux environment you must press the button for 30 seconds. Note that restoring the factory image make you lose all the files saved and softwares installed on the on-board flash memory connected to the AR9331.

See also the mapping between Arduino pins and ATmega32u4 ports.

Communication

The Yún has a number of facilities for communicating with a computer, another Arduino, or other microcontrollers. TheATmega32U4 provides a dedicated UART TTL (5V) serial communication. The 32U4 also allows for serial (CDC) communication over USB and appears as a virtual com port to software on the computer. The chip also acts as a full speed USB 2.0 device, using standard USB COM drivers. The Arduino software includes a serial monitor which allows simple textual data to be sent to and from the Arduino board. The RX and TX LEDs on the board will flash when data is being transmitted via the USB connection to the computer.

Digital pins 0 and 1 are used for serial communication between the 32U4 and the AR9331. Communication between the processors is handled by the Bridge library.

A SoftwareSerial library allows for serial communication on any of the Yún’s digital pins except for pins 0 and 1.

The ATmega32U4 also supports I2C (TWI) and SPI communication. The Arduino software includes a Wire library to simplify use of the I2C bus; see the documentation for details. For SPI communication, use the SPI library.

The Yún appears as a generic keyboard and mouse, and can be programmed to control these input devices using theKeyboard and Mouse classes.

The onboard Ethernet and WiFi interfaces are exposed directly to the AR9331 processor. To send and receive data through them, use the Bridge library. To configure the interfaces, you can access the network control panel as described in thegetting started page.

The Yún also has USB host capabilities through Linino. You can connect peripherals like USB flash devices for additional storage, keyboards, or webcams. You may need to download and install additional software for these devices to work. For information on adding software to the AR9331, refer to the notes on using the package manager.

Programming

The Yún can be programmed with the Arduino software (download). Select «Arduino Yún from the Tools > Board menu (according to the microcontroller on your board). For details, see the reference and tutorials.

The ATmega32U4 on the Arduino Yún comes preburned with a bootloader that allows you to upload new code to it without the use of an external hardware programmer. It communicates using the AVR109 protocol.

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

Automatic (Software) Reset and Bootloader Initiation

Rather than requiring a physical press of the reset button before an upload, the Yún is designed in a way that allows it to be reset by software running on a connected computer. The reset is triggered when the Yún’s virtual (CDC) serial / COM port is opened at 1200 baud and then closed. When this happens, the processor will reset, breaking the USB connection to the computer (meaning that the virtual serial / COM port will disappear). After the processor resets, the bootloader starts, remaining active for about 8 seconds. The bootloader can also be initiated by pressing the reset button on the Yún. Note that when the board first powers up, it will jump straight to the user sketch, if present, rather than initiating the bootloader.

Because of the way the Yún handles reset it’s best to let the Arduino software try to initiate the reset before uploading, especially if you are in the habit of pressing the reset button before uploading on other boards. If the software can’t reset the board you can always start the bootloader by pressing the reset button on the board.

USB Overcurrent Protection

The Yún has a resettable polyfuse that protects your computer’s USB ports from shorts and overcurrent. Although most computers provide their own internal protection, the fuse provides an extra layer of protection. If more than 500 mA is applied to the USB port, the fuse will automatically break the connection until the short or overload is removed.

Physical Characteristics

The maximum length and width of the Yún PCB are 2.7 and 2.1 inches respectively, with the USB connector extending beyond the former dimension. Four screw holes allow the board to be attached to a surface or case. Note that the distance between digital pins 7 and 8 is 160 mil (0.16″), not an even multiple of the 100 mil spacing of the other pins.

Using your Yun

There is an extensive Getting Started Guide and a number of tutorials found on the library reference page.