Most projects you create with the 8051 CPU require some form of display. The most common way to accomplish this is with the LCD (Liquid Crystal Display). LCDs have become a cheap and easy way to get text display for an embedded system Common displays are set up as 16 to 20 characters by 1 to 4 lines. We will here discuss about the LCD 16×2.
keypad module is widely used input device is used to take input from user process to get desired output according to human need. in this article we will learn to interface widely used 4x4 matrix keypad because of it's simple architecture and ease of interaction with MCU.