MI PROJECT INDUS UNIVERISTY EC 5TH SEM

PROJECT TOPIC

Interfacing 5X7 matrix LED display to 8051

Abstract

A 5x7 matrix LED Display board with 8051 microcontroller has been designed. The LED’s

are connected like a matrix with 7 rows of 5 LED’s per each row are designed on a board to display.

For a 5x7 LED matrix, it is impractical to assign one I/O pin per LED, as a 5x7 matrix requires 35

I/O pins. These characters are switched continuously with a delay of 10msec. This design can be

extended to number of units by using shift registers to display a message consisting of many

number of characters. By controlling the data bits connected to the LED’s, we can display any

character. The Block diagram of 5x7 LED matrix is show in the figure. The 5x7 LED matrix

display with 35 LED’s are arranged in 7 rows and 5 columns structure. The purpose of ULN2003A

here is to drive the column lines of the display. ULN2003A is a high voltage (50V), high current

(500mA per channel) Darlington transistor array. Each IC has 7 channels with individual output

clamp diodes. ULN2003A an active high device, which means a logic high must be applied to the

input to make the corresponding output high. The software required for displaying character ‘A’,

‘B’, ‘C’, etc. on the LED matrix, with a delay between each character display has been developed

in assembly of 8051. The hex code is downloaded on to the AT89c51 microcontroller and is

verified by interfacing the microcontroller pins. For any given character, a corresponding pattern

of LED is generated and is used to display the character at run time. The application and advantages

that can be used at public transport places like bus stop, railway station, and airport. For displaying

various important messages in hospitals, schools, colleges. In future development we can use GSM

technology to receive the data from remote location.

Project Manager:

1. Ami Goswami – 12BECR014

2. Vatsal Shah – 12BECR052