09-10-2010, 02:25 PM
Presented by:
B.GIRIJA
D.S.R.KRISHNA
N.GOWTHAMI
K.AZARNAVEED
Y.KUSUMA
PROJECT GUIDE: E.GIRIBABU
Abstract
It is an embedded controller circuit to switch on and off electrical appliances. This system will use normal TV remote control to send the control signal .The TV remote control sends different control signals as per the key pressed. This control can be used for decoding and select some of the out pin of the micro controller. The TV remote control sends control signals in the form of IR rays to the receiving unit. The receiving unit receives the IR signals. The IR signal will be converted into digital signal with the help of an IR receiver. The received signals are decoded by the micro controller and changes its output with respect to the code received. The remote transmitter used in this project is a TV remote control used for Phillips TVs. It sends the control signals, which are in RC5 protocol modulated on a 40khz carrier
The 89C2051 micro controller is used in this project. It is in the family of Intel 8051. It is a CISC type processor and having 256 instructions. It has a 16-bit timer and UART. The controller receives the signals, which are in RC5 protocol It decodes the control signals and changes the port status. Microcontrollers these days are silent workers in many apparatus, ranging from the washing machine to the video recorder. Nearly all of these controllers are mask programmed and therefore are of very little use for applications that require the programs to be changed during the course of execution. The remote receiving unit receives the IR signals coming from the TV remote control unit. These signals are converted into electrical signals by the help of IR receiver.
The IR sensor will receive the Infra Red signals send by the TV remote control. The control signals are modulated on 40khz signal in order to avoid external light. The sensor converts the IR signal into electrical signals with the help of photo diode and amplifies it. It also includes the filter circuit to demodulate the 40khz carrier signal. The sensor inverts the signals.
Controller controls speed of fan like ac induction motor, where unable to access motor.In every home we use many
electrical appliances switched on and off manually. In Industries, where a large number or a group of electrical appliances are to be controlled,this device is much useful.
