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    More info on the Arduino Yun can be found at the http://arduino.cc/en/Main/ArduinoBoardYun?from=Products.ArduinoYUN
Arduino Yun pinout
This is a fantastic pinout, I advise you to visit the site listed in the image and purchase the book with the pinouts
Arduino Yun Specs
| 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 | 
Links

Yun Electronics Development Microcontroller Board for Arduino (Works with Official Arduino Boards) – Green
from: TinyDeal


