How to make an alphabetic keypad using 8051 microcontroller (AT89C51)
An alphabetic keypad is similar to a numeric keypad, but it provides the complete set of alphabetical letters instead of numbers 0-9. This article presents a way to interface a keypad with 8051 microcontroller (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.
Every key is assigned with a variable to count the number of times it has been pressed. The count is set to zero initially and increases by one when the same key is pressed again.
A preset is a three legged electronic component which can be made to offer varying resistance in a circuit. The resistance is varied by adjusting the rotary control over it. The adjustment can be done by using a small screw driver or...
LCD (Liquid Crystal Display) screen is an electronic display module and find a wide range of applications. A 16x2 LCD display is very basic module and is very commonly used in various devices and circuits. These modules are preferred over seven segments...