Displaying ASCII Characters on 16x2 lcd with arduino

Displaying ASCII characters on MXN lcd is very easy. Where M represents number of coulombs and N number of rows. You just need to know about the internal structure of character lcds, registers of character lcds and the characters supported by lcd controller. Below tutorial will help you in knowing about the internal structure of lcd.

Internal Structure of Character lcd.

Normally lcd contains HD44780 controller in them. Hd44780 is responsible for all the communications with external controller and displaying text on lcd screen. HD44780 is designed by Hitachi and it supports 255 characters. Which means you can display 255 different characters on lcd directly through its controller. The supported characters are ASCII, Digits(0,9) and Japanese characters. Refer to data sheet of controller if you want to know about all characters and their address in ROM of hd44780 lcd controller.

How to display ASCII characters on Character lcd’s

Now to display ASCII character on 16×2 lcd simply pass the address of the ASCII characters present in 16×2 lcd controller ROM(read only memory). I did same in my code. Started from the first character and prints all of them one by one on lcd. Some characters are missing in ROM of hd44780 and special Japanese language characters are present on their locations. So some Japanese language characters will also be displaced on lcd. Few characters in ROM are greater than 5×10 font. These characters will not appear on lcd. Their decimal value will be displayed on lcd but they will not appear on the lcd.

Don’t know about 5×10, 5×8 character meaning. No problem just take the following tutorial(How to display 5×8 or 5×10 font character on 16×2 lcd?).

Hardware Requirements

16×2 Lcd
Arduino board(Microcontroller)
Potentiometer (To set lcd contrast)
Power supply

NOTE: You will see some spaces and weird shape characters displayed on lcd. Those characters are present in controller of 16×2 lcd that’s why they are displayed on lcd. Some Japanese characters will also be displayed on lcd. All the characters present in lcd controller will be displayed on lcd. Characters present in HD44780 lcd controller are given below. Pic is taken from data sheet of hd44780 lcd controller.

Ascii,digit(0,9) Japanese characters supported by character lcd controller

Project circuit diagram

Circuit diagram of the project and 16×2 lcd connections with arduino uno is given below. 16×2 lcd is interfaced in 4-bit mode with arduino.

ACSII characters display on 16x2 lcd using arduino uno

ACSII characters display on 16×2 lcd using arduino uno

Displaying Ascii characters on 16x2 lcd with Arduino

Displaying Ascii characters on 16×2 lcd with Arduino

ASCII characters on 16×2 lcd display using arduino – Project code

Coming to the project code. On first row of 16×2 lcd decimal values of ASCII characters will be displayed and on second row ASCII characters will be displayed. ASCII characters start from 34 location of the hd44780 ROM location. So in code i started the ASCII characters from 34th location.

Each character will appear on 16×2 lcd for 1 second after 1 second it disappears and the next ASCII character will appear on 16×2 lcd with its corresponding decimal value.

Some more projects on displaying ASCII characters on 16×2 lcd using various microcontrollers. Each project code is open source. You an use and modify it according to your needs.

ASCII characters display on 16×2 lcd with 8051 microcontroller

Displaying ASCII characters on 16×2 lcd with Pic microcontroller

Watch the Project video here

ASCII using Arduino code/files