[[wysiwyg_imageupload::]]AT89C51) to display alphabetical characters on an LCD module. Such kind of systems is commonly used in mobile phones to write an SMS and other texts. It can have further applications in displaying instant messages on other display systems such as LED matrices or other multi-segment displays. A 4x3 matrix keypad and a 16x2
LCD has been used here. Keypad and LCD are very commonly used input & output devices, respectively.
Keypad is a widely used input device with lots of application in our everyday life. From a simple telephone to keyboard of a computer, ATM, electronic lock, etc., [[wysiwyg_imageupload::]]keypad is used to take input from the user for further processing. In this article we are interfacing keypad with the MCU and displaying the corresponding number on . This module can be further used in a number of systems to interfaced keypad with microcontroller and other processors to get desired output. The program to interface keypad with controller is written in C language which is very easy to understand.