cell phone based device control

CELL PHONE BASED DEVICE CONTROLUNDER THE GUIDANCE OF “MS.G.SUSMITHA”Asst.Prof.

DEPARTMENT OF ELETRICAL AND ELECTRONICS ENGG.

GROUP MEMBERS:

A.VISHWANATH (09281A0233) K.BHAVANA

(0928A10246) D.SANTHOSH (09281A0209)

OBJECTIVE

Turning on/off the appliance with our cell phone.

Cell phone as the remote control for our home appliances.

System also gives voice acknowledgement of the

appliances status.

FEATURES

We can control up to 6 devices

There is no risk for false switching.

Before changing the state of the device we can confirm the present status of the device.

LAYOUT OF THE CIRCUIT

COMPONENTS USED

Regulator(7806-6V)Microcontroller(AT89C51)DTMF receiver(H9170B)Relay driver(L293D)Crystal oscillator(11.0592MHz,3.579MHz)Resistors(1K,10K,100K)Diode(IN4007)LED(5mm)Capacitors(0.1uf,4.7uf,10uf,33pf)Electret microphoneMobile phone headset connectorPush to on switch2 way DIP Switch

Power Supply Circuit

CIRCUIT DIAGRAM

INTERFACING OF SWITCHES WITH MICROCONTROLLER

SWITCHES MOBILE KEYS FUNCTIONS1 1 Select Device 1:On/Off

S2 2 Select Device 2:On/Off

S3 3 Select Device 3:On/Off

S4 4 Select Device 4:On/Off

S5 5 Select Device 5:On/Off

S6 6 Select Device 6:On/Off

S7 * Initialize to inform the status of the device

TABLE- I

CONTROL SOURCE SELECTION USING DIP SWITCHES

S17 S18 CONTROL STATUS

0 0 Rest Status

0 1 Switches Only

1 0 Mobile Only

1 1 Switches and Mobile

TABLE-II

RECORDING AND PLAYBACK TABLE

SWITCHES TRIGGER OF IC FUNCTIONSS9 1 NAME OF DEVICE 1

S10 2 NAME OF DEVICE 2

S11 3 NAME OF DEVICE 3

S12 4 NAME OF DEVICE 4

S13 5 NAME OF DEVICE 5

S14 6 NAME OF DEVICE 6

S15 7 STATUS” ON”

S16 8 STATUS” OFF”

TABLE III

INTRODUCTION TO MICROCONTROLLER

A single chip that contains:

a)Processor(CPU) b)Non volatile memory(ROM)

c)Volatile memory(RAM)d)Clock

e)I/O controlling unit CPU RAM ROM

I/O TIMER SERIAL COM PORT

AT89C51

6Interrupt sources1Serial port32I/O pins2Timer128 bytesRAM4K bytesROMQuantityFeature

INTERFACING DRIVER USING IC-L293D

L293D is a dual motor driver integrated circuit (IC). Motor drivers act as current amplifiers since they take a low-current control signal and provide a higher-current signal. This higher current signal is used to drive the motors.

In its common mode of operation, two DC motors can be driven simultaneously, both in forward and reverse direction. The motor operations of two motors can be controlled by input logic at pins 2 & 7 and 10 & 15. Input logic 00 or 11 will stop the corresponding motor. Logic 01 and 10 will rotate it in clockwise and anticlockwise directions, respectively.

DTMF DECODING USING IC-HT9170B.

Decodes the mobile signal.

It gets DTMF tone from the mobile headset’s speaker pins.

DECODING TABLE

KEY STD Q3 Q2 Q1 Q01 H 0 0 0 1

2 H 0 0 1 0

3 H 0 0 1 1

4 H 0 1 0 0

5 H 0 1 0 1

6 H 0 1 1 0

* H 1 0 1 1

# H 1 1 0 0

TABLE IV

Comparison between 8051 and Atmel

• 8051 and 89c51 are same architecture but difference is ROM memory .

• ROM less for 8051 while ROM (flash) for 89c51.

• it advanced EEPROM (flash) is difference.• it becomes possible for the 8051 designer to

directly start using 89SXX and 89S20XX microcontrollers without any more efforts in learning these microcontrollers.

ADVANTAGES OF THE PROJECT

Utilization Of Electrical power.

Power Conservation.

Design is small and portable.

Easy to use.

Economical.

LIMITATIONS

The receiver must reside where sufficient signal can be received from a cellular phone network.

The receiver must have a power source attached at all times.

Only 6 devices can be connected to the system.

SOFTWARE

The program (Device_Control.BAS) for the microcontroller is written using BASCOM microcontroller programming software.

In the program, first, initialize the ports (P0-P3) for corresponding controls. Thereafter, declare the variables for the program. After declaration, assign some initial value to variables. Here, microcontroller ports are initialized to make all the devices ‘off’ initially .

FUTURE SCOPE

In this project we are monitoring and controlling the home appliances from remote  places by using the mobile technology. This project can be further enhanced to the High voltage A.C Applications by changing the ratings of the Relay.

By this we can control and monitoring the high speed induction motors as well as synchronous motors. This can be done in an economical way

CONCLUSION

• The project “Development of Cell-phone Based

Device Control " an effective switching system for controlling home and office appliances.”

BIBLIOGRAPHY  

Reference Books: 1)Electronic Devices & circuits by J.B.GUPTA. 2)The 8051 Microcontroller And Embedded Systems by M.A.MAZIDI 3)Electronics For You Magazine.  Reference Websites:

 1) www.engineersgarage.com

2)www.efy.com

3)www.electronicsforu.com 

THANK YOU