This development board is a ESP8266 ESP-12 full evaluation board, The core ESP8666 module was mounted on a PCB with all the GPIO broken out.The board is powered by 3 x AA cells, and an onboard regulator ensures a neat 3.3V supply for the ESP8266.
Furthermore, each GPIO has an LED connected so you can quickly test your code without connecting external hardware, and a LDR to test the ADC.
When searching for this over a WiFi network, the device name is "AI-THINKER" and the password is "ai-thinker". There is also a example app for you to test this module with your android phone, please download  here.

The board defaulted to 115,200 baud out of the box. There's a circuit diagram in the second post of this thread:

http://www.esp8266.com/viewtopic.php?f=13&t=2694 (You need to be logged in to the site to see the download links)

JP4 shorts GPIO0 to ground to enter programming mode. Make sure this is removed to enter run program mode.
JP3 (solder pads) is to reset the device - it's handy to solder some pins on here or install a switch.

Features

• One high speed serial port
  
• One ADC
  
• Six I/O pins
  
• Three channels PWM
  
• Metal casing

• support wireless 802.11 b/g/n standard

• support the STA/AP/STA + AP three work modes

• support rich Socket the AT command

• support UART/GPIO data communication interface

• support Smart Link intelligent networking

• support the STA/AP/STA + AP three work modes

• built-in 32-bit MCU and can be applied as processor

• low power consumption, suitable for battery-powered applications

• Single 3.3 V power supply

• ESP8266 Community Forum

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