Reference

Library

Download Sample code and library.

The library supports the following functions:

• LiquidCrystal_I2C() //set the LCD address for a 16 chars and 2 line display
• init() //Initialization for the LCD
• clear() //clear display, set cursor position to zero
• home() //set cursor position to zero
• createChar() //Fill the first 8 CGRAM locations with custom characters
• setCursor() //set the position of the cursor
• cursor() //Turns the underline cursor on
• noCursor() //Turns the underline cursor off
• blink() //Turn on the blinking cursor
• noBlink() //Turn off the blinking cursor
• display() //Turn the display on(quickly)
• noDisplay() //Turn the display off(quickly)
• backlight() //Turn the backlight on
• noBacklight() //Turn the backlight off
• scrollDisplayLeft() //Make the display scroll left without changing the RAM
• scrollDisplayRight() //Make the display scroll right without changing the RAM
• autoscroll() //This will 'right justify' text from the cursor
• noAutoscroll() //This will 'left justify' text from the cursor
• leftToRight() //This is for text that flows Left to Right
• rightToLeft() //This is for text that flows Right to Left

Communication Protocol Description

The module uses I2C (Inter-Integrated Circuit) communication protocol. Key parameters:

• I2C Address range: 0x20-0x27 (default: 0x20)
• Interface: I2C/TWI x1, Gadgeteer interface x2
• Supply voltage: 5V

API Description

The library provides the following functions for controlling the LCD module:

• LiquidCrystal_I2C(): Set the LCD address for a 16 chars and 2 line display.
• init(): Initialize the LCD.
• clear(): Clear the display and set the cursor position to zero.
• home(): Set the cursor position to zero.
• createChar(): Fill the first 8 CGRAM locations with custom characters.
• setCursor(): Set the position of the cursor.
• cursor(): Turn on the underline cursor.
• noCursor(): Turn off the underline cursor.
• blink(): Turn on the blinking cursor.
• noBlink(): Turn off the blinking cursor.
• display(): Turn the display on quickly.
• noDisplay(): Turn the display off quickly.
• backlight(): Turn the backlight on.
• noBacklight(): Turn the backlight off.
• scrollDisplayLeft(): Make the display scroll left without changing the RAM.
• scrollDisplayRight(): Make the display scroll right without changing the RAM.
• autoscroll(): Right justify text from the cursor.
• noAutoscroll(): Left justify text from the cursor.
• leftToRight(): Set text flow from left to right.
• rightToLeft(): Set text flow from right to left.

Contrast Adjust

The contrast can be adjusted by the potentiometer displayed in the following picture:

Address Setting

The I2C address of the module can be set by the jumper caps. The address is determined by the A2, A1, and A0 pins:

• 0: The Jumper Cap is connected.
• 1: The Jumper Cap is disconnected.

The default address is 0x20. All the jumper caps will be connected from the factory.

Old Version and Projects

• Old version wiki: I2C/TWI LCD1602 Module
• Projects: DYP-ME007 Ultrasound range finder - display distance on a I2C 2x16 LCD

Power Pinout Note

V1.2 has a different power pinout from V1.1, please check the history version for the old connection diagram.