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Today in the workshop we will look at Liquid Crystal Displays or LCD’s.

We will examine the use of two type of LCD displays – the common LCD1602 display module and a popular LCD Keypad Shield for the Arduino. We’ll also see how to use the I2C adapter for the LCD1602 display module.

LCD’s are a very simple way to add display capabilities to your Arduino project. They are inexpensive, easy to use and very versatile. They also don’t consume a lot of current you they are ideal for battery powered projects.

I’ll show you a couple of ways to interface an LCD with an Arduino, including the use of an I2C adapter. If you’re not familiar with the I2C (Inter-Integrated Circuit) bus it’s a very versatile method of adding sensors and peripherals to your Arduino using only a few wires. I’ll give a brief explanation about the operation of the IC2 bus in the video.

To use the I2C adapter we’ll make use of a library called NewLiquidCrystal. I’ll show you how to install it, you’ll find the link to this library in the article at . The library is actually a replacement for teh Arduino LiquidCrystal library so you can use it for all your LCD sketches, not just the I2C ones.

We will also build something practical while we are at it – a digital temperature and humidity gauge. This will make use of the I2C adapter and the DHT22 temperature and Humidity sensor.

The video, and the accompanying article, will also show you how to use a very common LCD Keypad Shield for the Arduino Uno. The neat thing about this device is in how the push buttons are wired. I’ll explain that and show you a demonstration sketch that you can build upon for your own projects.

Here is the Table of Contents for this video:

The LCD1602 Display Module – 4:27
Hooking up the LCD and Arduino – 7:04
Demo Sketch 1 – Hello World – 9:49
Demo Sketch 2 – Scroll – 12:59
Demo Sketch 3 – Custom Characters – 15:39
Introducing I2C – 20:00
Hooking up the I2C Adapter – 23:44
I2C Address Test – 26:15
I2C Display Test – 27:08
Building the Temperature & Humidity Gauge – 32:48
LCD Keypad Shield – 37:39
LCD Keypad Shield Demo Sketch – 41:00

By the way I should mention I had a “slip of the tongue” while narrating this video. During the “Custom Character” demo I described the LCD as having a 5 x 7 matrix, it’s actually 5 x 8. Sorry about that! One extra row for you to define your custom characters.

The article accompanying this video at contains a link to a very handy resource, an online custom character generator that you can use to write the code to define your own custom characters. You’ll want to check that out.

As usual the article has links to more resources and to a ZIP file with all of the code you see displayed here.

Hope you enjoy this video and that you use it to display something wonderful in your next Arduino project!


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