Serial I2C LCD Display Adapter

Serial I2C LCD display adapter converts parallel based 16 x 2 character LCD display into a serial i2C LCD that can be controlled through just 2 wires. Adapter uses PCF8574 chip that serves as I/O expander that communicates with Arduino or any other microcontroller by using I2C protocol. A total of 8 LCD displays can be connected to the same two wire I2C bus with each board having a different address. The default i2C address is 0X27 and may be changed to any of the following 0X20~0X27 via soldering A0 A1 A2 pins. 

Features

• 16 x 2 Character LCD display is controlled via just two wires 
  
• Up to 8 LCD displays with adapters can be connected and controlled by the same two wire I2C bus 
  
• Easy to control using Arduino board 
  
• Compatible with 16 x 2 character LCD displays 
  
• Adapter includes 16-PIN male header connector for soldering to LCD display 
  
• Contrast is adjusted via onboard potentiometer 
  
• Backlight may be turned on/off via jumper 
  
• Standard 5V voltage supply
  

Tutorial

http://tronixstuff.com/2014/09/24/tutorial-serial-pcf8574-backpacks-hd44780-compatible-lcd-modules-arduino/