shift the value one bit to the right), yielding an address between 0 and 127.

If you have a datasheet or sample code that uses 8 bit address, you'll want to drop the low bit (i.e. The Wire library uses 7 bit addresses throughout.

7 bits identify the device, and the eighth bit determines if it's being written to or read from. There are both 7- and 8-bit versions of I2C addresses. Because of this, send() and receive() have been replaced with read() and write(). The Arduino Due has two I2C / TWI interfaces SDA1 and SCL1 are near to the AREF pin and the additional one is on pins 20 and 21.Īs a reference the table below shows where TWI pins are located on various Arduino boards.Īs of Arduino 1.0, the library inherits from the Stream functions, making it consistent with other read/write libraries. On the Arduino boards with the R3 layout (1.0 pinout), the SDA (data line) and SCL (clock line) are on the pin headers close to the AREF pin. This library allows you to communicate with I2C / TWI devices. If you want to use more than one display, they need to have different addresses (more on this in the video) and this library can either autodetect them or you can specify the addresses (detail on this is in the gitHub documentation and in the example sketches.Reference Language | Libraries | Comparison | Changes.This library will autodetect your I2C displays and you do not need to specify the address of the device.The example sketches will then also be available in the Open file dialogue. In the library manager, search for hd44780 and then download it - it will soon be ready to use and will appear in your libraries menu. The best way to get the library is to open your Arduino software and go to the menu:.

Since that video was made, we have switched to using the hd44780 Library:Ĭreated by Bill Perry example code is unlicensed and is released into the public domain Wire is already included in the Arduino IDE but you will need to download NewLiquidCrystal - click here to download: In our video, we used the NewLiquidCrystal Library. T o use an I2C ready LCD Display or I2C Backpack Adaptor Module with Arduino you will need the Wire Library and a Library for I2C LCD. I2C Arduino Code for LCD Displays & Adaptor ModulesĬlick Here to watch our YouTube Video for a full description

Arduino library wire download