Submitted by: Submitted by hasan45saeed
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Words: 2104
Pages: 9
Category: Science and Technology
Date Submitted: 02/18/2013 10:57 AM
Rotating Light Emitting Diodes (LED) Display: Based on the principle of the
persistence of vision
Made By:
Hassan Saeed Al-Qadheeb
Under Supervision and Guidance of:
Dr. Hesham Enshasy
January 2013
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Abstract
This report introduces the reader how to build a virtual display consisting of only
seven rotating light emitting diodes (LED’s) to show any word or shape on it. It
will also give the reader enough information to start using microcontrollers and
also provide instructions to build and program the rotating display.
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Contents
1- Introduction ……………………………………………………… Page 4
2- Objectives ………………………………………………………… Page 5
3- Methodologies ……………………………………………………. Page 5
Block Diagram ……………………………………………….. Page 5
Hardware Description ……………………………………….. Page 6
4-Design …………………..………………………………………….. Page 7
5-Programming the Rotating Display ………………...……………. Page 9
6-Testing the Rotating Display ……………………………………… Page 13
7- References …………………………………...…………………….. Page 15
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1-Introduction
This report describes the idea of a rotating light emitting diode (LED)
display, consisting of only seven LED’s. The principle is that the LED’s are placed
on a rotating vertical arm , and are switched on and off at exactly the right times to
convince the eye that you are looking at the seven by 35 matrix of LED’s forming
a letter. The LED’s are switched on and off by the microcontroller that is rotating
along with the LED’s. A CPU used for rotating the microcontroller and the LED’s.
This project was started with a simple which is Persistence of Vision (POV).
This phenomenon makes eyes feel fast moving objects to appear continuous (as an
example see figure 1).
Figure 1: Persistence of Vision, Coins example
Also the television is a very common example; in which image is rescanned every fraction of second, thereby appear continuous. Further, a glowing
objects if rotated in a circle at fast speed, it shows a continuous circle. By...