Al-Azhar University-Gaza

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Faculty of Engineering & Information

Technology

Microprocessors & Interfacing

(ITCE 3306)

LAB NO.3

7-Segment Display

Prepared By:

Ronza sameer Abu jayyab

No. 20111511

Submitted To:

Eng. Mahmoud I. Hasanain

First semester

2013/2014

Date: 12/11/2013

Introduction:

In this lab will develop capabilities in dealing with 7-segment and how we can

display out put in its screen.

Objectives:

- Understand how 7-segment work and display out put in its screen.

- Know how to deal with type of 7-segment technique (multiplexing and

demultiplexing).

Background:

Light emitter diodes (LEDs):

Seven segment displays:

Binary to 7-segment decoder driver: BCD to 7-segment display controller:

Interfacing 7-segment to PC through parallel printer port: Demultiplexing technique:

Multiplexing technique:

Expriments:

Experiments general steps: i. Connect 7-segment with Vcc voltage.

ii. Connect resister from the other side of the 7-segment.

iii. Then, connect 7-segment with resister with the 74Ls47.

Experiment no. (1): Seven-segment interface display no. from 0 to 9.

Interface one 7-segment displays with a PC through the parallel printer

board (LPT) to display numbers from 0-9.

Experiments spical steps:

1. Connect one 7-segment with Vcc = 5V.

2. Connect 7-segment from other side with seven resister.

3. Connect 7 resisters from other side with 74LS47 decoder.

4. Then, connect D0, D1, D2, D3 which out from 74LS47 decoder

with

Control code:

Fig-1-

Experiment no. (2): Seven-segment interface using demultiplexing.

Using demultiplexing technique provide an interface of two 7-segment

displays to a PC through the parallel printer board (LPT), to display

numbers from 0 to 99.

Expriments spical steps:

1. Connect two 7-segment togather.

2. Then, connect them with voltage Vcc= 5V.

3. Connect each 7-segment from other side with seven resister.

4. Connect 7 resisters for first 7-segment with D0, D1, D2, D3 from

74LS47 decoder and second 7-segment with D4, D5, D6, D7 with

other side from 74LS47 decoder.

5. Finally, Then, connect D0, D1, D2, D3, D4, D5, D6, D7 which out

from 74LS47 decoder with

Control code:

Fig-2-

Experiment no. (3):

seven segment interface using multiplexing.

Using multiplexing technique provide an interface of 4 7-segment displays

to a PC time through the parallel printer board (LPT).

Experiments spical steps:

1. Connect 4 7-segment togather then connect them with Vcc voltage

equal 5V.

2. Joint each 7-segment with 7 resisters.

3. Joint 74LS47 decoder from the other side of resisters.

4. Use pnp transistor and connect four transistors with 4 7-segments.

5. Connect each transistor with resister (R=5Kohm or 4.7Kohm).

Fig-3-

Control code:

Fig-4-

Referance: