Arduino Yún

Arduino Yún ATmega32u4 Microcontroller Board

Product Description:
The Arduino Yún is a microcontroller board based on the ATmega32u4 (datasheet) and the Atheros AR9331. The Atheros processor supports a Linux distribution based on OpenWrt named OpenWrt-Yun. The board has built-in Ethernet andWiFi support, a USB-A port, micro-SD card slot, 20 digital input/output pins (of which 7 can be used as PWM outputs and 12 as analog inputs), a 16 MHz crystal oscillator, a micro USB connection, an ICSP header, and a 3 reset buttons.

The Bridge library facilitates communication between the two processors, giving Arduino sketches the ability to run shell scripts, communicate with network interfaces, and receive information from the AR9331 processor.

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
Card Reader: Micro-SD only
RAM: 64 MB DDR2
Flash Memory: 16 MB
PoE compatible: 802.3af card support (see the note below)
Length: 73 mm
Width: 53 mm
Weight: 32 g