Tag Archives: display

Three Wire LCD Interface with Arduino

We have seen parallel interface technique using Arduino library and we know that it requires 6 IO Lines, Now let’s see how we can reduce required IO’s using 74HC595. We know that we can reduce number IO required by using I2C based LCD interface circuit; It costs ten times more than 74HC595 Circuit.

Arduino 3 wire LCD interface circuit

            In this circuit similar to the bargraph display we are using 74HC595 Shift register to interface 16×2 LCD. Continue reading Three Wire LCD Interface with Arduino

Four Digit 7-Segment Display Interfacing with Arduino

7-segment displays are most popular in panel meters, It can show direct numerical value on display, It’s cost is low and display size bigger than LCD’s. Lets interface four digit display, most of the time four digits are enough to display data.

Problem Statement

We are making a Voltmeter using four digit 7-segment display, for this IC 74HC595 shift register is used instead of 7448 decoder, use of shift register gives few advantages such as you can display sign, few alphabets and control decimal point location. Continue reading Four Digit 7-Segment Display Interfacing with Arduino

RGB LED Interfacing with Arduino

In some cases you need to display a static text with different colors, for this purpose you can use RGB LED Strips. In this tutorial we will learn how to interface RGB LED strip with arduino and drive it using ULN2003.

rgb-led-strip

This is a basic tutorial for using Common Anode RGB LED Strip, PWM, and switch. By the end, you will have single switch to control colors of the LED strip. Connect the LED’s anode lead to +12V and connect the 3 RGB cathode leads to digital pins 9, 10, 11 through ULN2003 respectively.

RGB LED Strip Pin out
RGB LED Strip Pin out

RGB LED Strip Connections with Arduino

To drive complete RGB LED Strip we have used ULN2003 as a driver circuit, LED strip works at 12V. You can combine ULN2003 driver outputs to get more current.

RGB LED Arduino Interfacing Circuit
RGB LED Arduino Interfacing Circuit

Arduino Code for RGB LED Color Control

Results

Press switch and see that we have around ten different colors; You can change the color using SetColor(R,G,B). try different values of RGB.

Moving message display using arduino

Matrix Display Interface with MAX7219

The MAX7219 LED driver saves microcontroller pins and processing time. It uses only three IO pins of an Arduino.  It is easy to connect multiple displays by connecting DIN and DOUT pins.

Using a single MAX7219 you can drive 64 LEDs while you only need 4 wires to interface it to a microcontroller. In addition you can daisy chain multiple MAX7219 chips for bigger displays. Continue reading Moving message display using arduino

LCD interface using I2C Module with Arduino

I2C module with LCD display using Arduino

 How to interface PCF85574 module with arduino?
To connect LCD display 16×2 or 20×4 to Arduino you know you’ll need at least 6 wires to connect, it means sacrificing some IO’s that could be used for connecting other components such as sensors or motors. another way is to use 74HC595 Shift register for interfacing. In this tutorial we will discuss on PCF85574 I2C LCD Display Interface.
A module that can be used to circumvent this problem is the I2C Module for LCD Display with PCF85574 (datasheet ):

Continue reading LCD interface using I2C Module with Arduino