Electrical and Electronics Mini Project Report on Control of Pc With Tv Remote Cusat University

PC CONTROLLED WITH TV REMOTE

MINOR PROJECT REPORT

In partial fulfillment of the requirements for the Degree of

BACHELOR OF TECHNOLOGY (B-TECH) In

ELECTRICAL AND ELECTRONICS Of

COCHIN UNIVERSITY OF SCIENCE AND TECHNOLOGY

Submitted by

AJU M.T. GOPIKRISHNAN K.

NITHIN P. RANJITHA P.V. SARANYA M.

DEPT.OF ELECTRICAL AND ELECTRONICS ENGINEERING COLLEGE OF ENGINEERING TRIKARIPUR

CHEEMENI-671 313, KASARGOD 2010

DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING

COLLEGE OF ENGINEERING TRIKARIPUR

Certificate

This is to certify that this is a bonafide record of the project work entitled

“PC CONTROLLED WITH TV REMOTE” done by the following students

AJU M.T.

GOPIKRISHNAN K.

NITHIN P.

RANJITHA P.V.

SARANYA M.

Of the sixth semester, Electrical and Electronics Engineering in the year 2010

in partial fulfillment of the requirements to the award of Degree Bachelor of

Technology , in Electrical and Electronics Engineering of Cochin University of

Science and Technology.

Project Guide Project coordinator Head of the Department Mrs. FOUSIYA K. Sri.GIREESHKUMAR A. Sri.KUNHIRAMAN A. Lecturer Lecturer Head of the department Dept. of Electrical & Dept. of Electrical & Dept. of Electrical & Electronics Engg. Electronics Engg. Electronics Engg.

ACKNOWLEDGEMENT

We take this occasion to thank GOD ALMIGHTY for giving us the favour

to complete this project to the extent of our knowledge and capabilities.

We are extremely grateful to the principal Sri. Dr. V.V.KARUNAKARAN,

College of Engineering Trikaripur, Cheemeni for providing the necessary

facilities.

We express our sincere thanks to our respected Head of the Department

Sri.KUNHIRAMAN A. for allowing us to use the facilities available. We also

thankful to Sri.GIREESHKUMAR A. Lecturer in Electrical and Electronics

Engineering, for his valuable guidance in this project. We extend our sincere

and heartfelt thanks to our esteemed guide, Mrs. FOUSIYA K. Lecturer in

Electrical and Electronics Engineering, for providing us with the right guidance

and advice at the crucial junctures and for showing us the right way.

We would like to thank the other faculty members also, at this occasion.

Last but not the least, we would like to thank friends for the support and

encouragement they have given us during the course of our work.

AJU M.T.

GOPIKRISHNAN K.

NITHIN P.

RANJITHA P.V.

SARANYA M.

ABSTRACT

As the name specifies “PC CONTROLLED WITH TV REMOTE” is a

circuit developed for controlling the computer with a TV remote. Mouse is an

integral part of computer which provides an easy interface with system. Both

corded and cordless or Bluetooth mouse are available in the market. But their

range of operation has always been a major constraint for users. Through our

project we have tried to increase the range to a comfortable level. For the TV

remote to work you need a device that decodes IR remote control data signals

and a PC application that communicates to this device connected to PC.

Here we used a remote control for PHILIPS TV as the PC REMOTE

since it is cheaply available. The Philips TV remote uses the IR signal within an

encoded protocol known as RC5 protocol.

The circuit can realized using digital ICs and discrete components. But

our design involves a microcontroller because it greatly simplifies the job at the

same time gives the designer great flexibility and plenty of features- all can be

accessed through the software. We selected AT89C2051 Microcontroller of

ATMEL to start our journey to the fascinating world of embedded controllers.

The AT89C2051 is a 20 pin, low-voltage, high-performance CMOS 8-bit

microcomputer with 2K bytes of Flash programmable and erasable read-only

memory (PEROM).It uses the interrupt of the microcontroller to receive the

encoded data from the Infrared receiver. Microcontroller decodes the RC5

encoded data into simple BCD and converts it to serial data which can be

taken out from the serial out pin of the Microcontroller. To interface the

microcontroller TTL logic to the RST232 logic of the computer we use a driver

IC. The output of the driver IC is connected to the PC COM port. In the

computer an application receives the serial data and a predefined action is

done according to it.

CONTENTS PAGE NO.

1. INTRODUCTION 1

2. BLOCK DIAGRAM 2

3. WORKING PRINCIPLE 3

4. CIRCUIT DIAGRAM 4

5. COMPONENTS LIST 5

6. FLOW CHART 6

7. DESCRIPTION OF COMPONENTS 10

8. PROGRAMME 21

9. EVALUATION 29

10. PRINTED CIRCUIT BOARD 30

11. COST ESTIMATION 35

12. CONCLUSIONS 36

13. REFERENCE 37

14. DATASHEETS 38

Project Report -2010 Control Of PC With TV Remote

Dept. of EEE 1 College of Engineering Trikaripur

1. INTRODUCTION

The invention of microcontrollers is the cutting edge of futuristic technology. Microcontrollers have made a deep impact in various fields of science, engineering and technology. The main perspective of this project is to study various functions of AT89C2051 as a controlling device. AT89C2051 is a powerful microcomputer which provides a highly-flexible and cost-effective solution to many embedded control applications. This powerful yet easy to program CMOS 8-bit microcomputer with 2K bytes of flash programmable and erasable read-only memory (PEROM). This device easily adaptable for automotive, industrial, appliances and consumer entry level product applications that require field re-programmability. In our project we use this chip as the main component of the system. It receives the RC5 encoded IR signal from the receiver and produces equivalent serial 8bit binary output in serial out pin. The major part of this project is the decoding of the RC5 signal. All those function of decoding is done by the microcontroller.

Visual Basic is a tool that allows you to develop Windows (Graphic User Interface - GUI) applications. The applications have a familiar appearance to the user. In the PC the installed software PC REMOTE.exe is created in visual basic. In this programme we have written that what to do when different serial data appears in the serial port of the PC. All the actions were predefined in this application. Actually this software is doing all the actions like mouse control, media player control etc according to remote control operation.



2. BLOCK DIAGRAM



3. WORKING THEORY

A 230/12v transformer is used to step down 230v to 12v which is fed to the bridge rectifier. The output is fed to the input of regulator IC (LM7805). Thus a constant voltage of 5V is obtained. Capacitors of value 1000µF are used to remove high frequency ripples.

Thus 5V is fed to the IR receiver, AT89C2051- Microcontroller and driver IC MAX-232.

There is IR receiver which receives the 14Bit RC5 encoded IR signal from the TV remote which is connected to the microcontroller. The IR receiver converts the IR signal to 14 bit 5V peak pulse train. Microcontroller decodes the 14Bit pulse train. Since we just need the 6 command bits, one toggle bit and one start bit the program is written to out only 8Bit from the 14Bit input. Microcontroller outs the 8Bit data as serial data through the serial data out pin of the microcontroller. The microcontroller is of CMOS logic and the PC COM port of the PC is of RST232 logic therefore a TTL/CMOS-RST232 driver/receiver IC is used. Thus the 8Bit BCD data corresponding to a specific button in the remote appears in the PC-COM port of the computer.

The software PCREMOTE.exe installed in the computer is started. Then it starts to read the 8Bit BCD data in the RST port. Corresponding to the 8Bit data a predefined action will be done by the software like mouse up, mouse down, right mouse click, launching windows media player, volume up, volume down etc. When the application PCREMOTE.exe is closed the control on the PC with TV remote ends.



4. CIRCUIT DIAGRAM



5. COMPONENTS LIST

COMPONENTS

SPECIFICATION

µC

IC1

Resistors

R5

Capacitors

C2,C3

C6

C4,C7,C8,C9,C10

Miscellaneous

IRX1

LED1

S1

XTAL1

AT89C2051

MAX232

10kΩ

33pF

10OnF

10µF,60V

TSOP 1738

RED

MICROSWITCH

11.0592MHz



YES

6.FLOW CHART

START

INITIALISE VARIABLES TEMP,ADDR, CMD, COUNT

CLEAR RAM

READ 1’ST BIT

IS BIT

HIGH

DELAY 3.024mS

INITIALISE COUNT=5

READ BIT FROM P3.3

DELAY 1.728mS

A

B

NO



YES

YES

NO

INITIALISE COUNT=6

READ BIT FROM SERIAL PORT

DELAY 1.728mS

DECREMENT COUNT

IS COUNT

=0

DECREMENT COUNT

IS COUNT

=0

STORE ADDR

STORE IN ACCUMULATOR

B

NO



YES

YES

IS ADDR =00H

SET MODE=0

IS MODE=

0

A

SERIAL TRANSMIT MODE, TOGGLE, CMD

KEYBOARD

STORE IN CMD

MOUSE

NO

NO



KEYBOARD

IS TEMP=CMD

COMPLEMENT TOGGLE

RETURN

MOUSE

IS TEMP=CMD

COMPLEMENT TOGGLE

RETURN



7. DESCRIPTION OF COMPONENTS 7.1.POWER SUPPLY

CIRCUIT DIAGRAM

Power supply section generates a regulated voltage of 5V from the 230V 1phase AC supply. Regulated 5V uses for power up microcontroller and other components. The line voltage 230VAC applied to the primary of the transformer (230/12,250mA). It’s secondary 12V rectified using bridge rectifier and filtered using 1000µF electrolytic capacitor. This filtered 5V supply is given to the LM7805 voltage regulator. This gives a regulated 5V DC supply.

7.2. LM7805 VOLTAGE REGULATOR Features

Output Current up to 1A Output Voltage of 5V Thermal Overload Protection Short Circuit Protection Output Transistor Safe Operating Area

Protection



7.3. TV REMOTE

The TV remote here we used is the remote PHILIPS RC7812.It uses a protocol invented by PHILIPS known as RC5 protocol.

7.3.1. RC5 protocol The RC-5 code from Philips is possibly the most used

protocol by hobbyists, probably because of the wide availability of cheap remote controls. The protocol is well defined for different device types ensuring compatibility with our whole entertainment system.

Features

5 bit address and 6 bit command length Bi-phase coding (aka Manchester coding) Carrier frequency of 36kHz Constant bit time of 1.778ms (64 cycles of 36 kHz) Manufacturer Philips

The protocol uses bi-phase modulation (Manchester

coding) of a 36 kHz IR carrier frequency. All bits are of equal length of 1.778ms in this protocol, with half of the bit time filled with a burst of the 36 kHz carrier and the other half being idle. A logical zero is represented by a burst in the first half of the bit time. A logical one is represented by a burst in the second half of the bit time. The pulse/pause ratio of the 36 kHz carrier frequency is 1/3 or 1/4 which reduces power consumption.



7.4. IR RECEIVER The IR receiver here used is the widely used IR

receiver TSOP1738. The TSOP1738 is a miniaturized receiver for infrared remote control systems. PIN diode and preamplifier are assembled on lead frame, the epoxy package is designed as IR filter. The demodulated output signal can directly be decoded by a microprocessor/ microcontroller. TSOP1738 is the standard IR remote control receiver series, supporting all major transmission codes.

Features

Photo detector and preamplifier in one package Internal filter for PCM frequency Improved shielding against electrical field disturbance TTL and CMOS compatibility Output active low Low power consumption High immunity against ambient light Continuous data transmission possible (up to 2400 bps)

From the datasheet the output of the IR receiver in a circuit can be improved by the recommended settings from the manufacturer. *) Recommended to suppress power supply disturbances **) The output voltage should not be hold continuously at a voltage below 3.3V by the external circuit.



7.5. MICROCONTROLLER

A microcontroller is a computer-on-a-chip, containing a processor, memory, and input/output functions. It is a microprocessor emphasizing high integration, in contrast to a general-purpose microprocessor (the kind used in a PC).In addition to the usual arithmetic and logic element of a general purpose microprocessor, the microcontroller integrates additional elements such as read-write memory for data storage, read-only memory for program storage, peripheral devices, and input/output interfaces. At clock speeds of as little as a few MHz or even lower, microcontrollers often operate at very low speed compared to modern day microprocessors, but this is adequate for typical applications. They consume relatively little power (mile watts), and will generally have the ability to sleep while waiting for an interesting peripheral event such as a button press to wake up again to do something. Power consumption while sleeping may be just nano watts, making them ideal for low power and long lasting battery applications. The microcontroller we used is the AT89C2051 manufactured by ATMEL Corporation. It is a 20 pin flash based 8bit CMOS microcontroller. The embedded software of the microcontroller decodes the RC5 signal from the remote, which is the major function in this project. This chip includes high performance RISC CPU with plenty of features. Besides it is a low priced and easily available.

7.5.1. AT89C2051 Features

Some of the special features of this microcontroller are given below.

Compatible with MCS®-51Products 2K Bytes of Reprogrammable Flash Memory –

Endurance: 10,000 Write/Erase Cycles 2.7V to 6V Operating Range Fully Static Operation: 0 Hz to 24 MHz Two-level Program Memory Lock 128 x 8-bit Internal RAM



15 Programmable I/O Lines Two 16-bit Timer/Counters Six Interrupt Sources Programmable Serial UART Channel Direct LED Drive Outputs On-chip Analog Comparator Low-power Idle and Power-down Modes Green (Pb/Halide-free) Packaging Option

7.5.2. PIN Diagram

Microcontroller communicates input/output devices through it’s ports. In AT89C2051 there are 15 I/O ports available for the user. They can be use as general digital input or output pins. Some I/O pins occupy other functions as interrupts, counter, serial input/output ports, timers etc. they are selected in software routines according to the logic of the program. A description of the I/O ports of the AT89C2051 is given below. PORT 1 The Port 1 is an 8-bit bi-directional I/O port. Port pins P1.2 to P1.7 provide internal pull-ups. P1.0 and P1.1 require external pull-ups. P1.0 and P1.1 also serve as the positive input (AIN0) and the negative input (AIN1), respectively, of the on-chip



precision analog comparator. The Port 1 out-put buffers can sink 20 mA and can drive LED displays directly. When 1s are written to Port 1 pins, they can be used as inputs. When pins P1.2 to P1.7 are used as inputs and are externally pulled low, they will source current (IIL) because of the internal pull-ups. Port 1 also receives code data during Flash programming and verification. PORT 3

Port 3 pins P3.0 to P3.5, P3.7 are seven bi-directional I/O pins with internal pull-ups. P3.6 is hard-wired as an input to the output of the on-chip comparator and is not accessible as a gen-eral-purpose I/O pin. The Port 3 output buffers can sink 20 mA. When 1s are written to Port 3 pins they are pulled high by the internal pull-ups and can be used as inputs. As inputs, Port 3 pins that are externally being pulled low will source current (IIL) because of the pull-ups.

Port Pin

Alternate Functions

P3.0 RXD (serial input port) P3.1 TXD (serial output port) P3.2 INT0 (external interrupt 0) P3.3 INT1 (external interrupt 1) P3.4 T0 (timer 0 external input) P3.5 T1 (timer 1 external input)

7.6 DRIVER IC

The maximum current that can be delivered by a AT89C2051 microcontroller is 25mA. Thus the serial output taken from the microcontroller is of TTL/CMOS logic. In TTL/CMOS logic the logic levels are +5V and 0V.Where the PC COM port works in a different communication standard known as Serial RS-232. Thus the RS-232 signal levels are far too high TTL electronics, and the negative RS-232 voltage for high can’t be handled at all by computer logic. This communication works with voltages -15V to +15V for high and low. To receive serial data from an TTL/CMOS interface the voltage has to be up. When communicating with PC COM port we need to convert



the TTL/CMOS levels up to higher levels, typically -15V & +15 Volts.

Here the level converter uses a Max232 and five capacitors. The MAX232 from Maxim was the first IC which in one package contains the necessary drivers and receivers to adapt the TTL signal voltage levels to RS-232 logic. It became popular, because it just needs one voltage (+5V or +3.3V) and generates the necessary RS-232 voltage levels.

7.6.1 Features

The driver IC MAX232 has the following features.

Operate from Single +5V Power Supply Low-Power Receive Mode in Shutdown Meet All EIA/TIA-232E and V.28 Specifications Multiple Drivers and Receivers 3-State Driver and Receiver Outputs



7.6.2 Pin Diagram The MAX232 have two internal charge-pumps that convert

+5V to ±10V (unloaded) for RS-232 driver operation. The first converter uses capacitor C1 to double the +5V input to +10V on C3 at the V+ output. The second converter uses capacitor C2 to invert +10V to -10V on C4 at the V- output. A small amount of power may be drawn from the +10V (V+) and -10V (V-) outputs to power external circuitry. V+ and V- are not regulated, so the output voltage drops with increasing load current.

7.7. PC COM PORT

The UART serial port (serial Com port) is an I/O (Input/output) device. An I/O device is just a way to get data into and out of a computer using. There are many types of I/O devices such as serial ports, parallel ports, disk drive controllers, ethernet boards, universal serial buses, etc.



Most PC's have one or two serial ports. Each has a 9pin connector (sometimes 25pin) on the back of the computer. Computer programs can send data (bytes) to the transmit pin (output) and receive bytes from the receive pin (input). The other pins are for control purposes and ground. The serial port is much more than just a connector. It converts the data from parallel to serial and changes the electrical representation of the data. Inside the computer, data bits flow in parallel (using many wires at the same time). Serial flow is a stream of bits over a single wire (such as on the transmit or receive pin of the serial connector).

Old PC's used 25 pin connectors but only about 9 pins were actually used so today most connectors are only 9pin.Each of the 9 pins usually connects to a wire. Besides the two wires used for transmitting and receiving data, another pin (wire) is signal ground. The voltage on any wire is measured with respect to this ground. Thus the minimum number of wires to use for 2-way transmission of data is 3. There are still more wires which are for control purposes (signaling) only and not for sending bytes. All of these signals could have been shared on a single wire, but instead, there is a separate dedicated wire for every type of signal.



7.8. PC REMOTE.exe It is a windows application created in the visual basic programming language. For the working of this PC remote this application should be installed in the computer. This program scans the serial port frequently when it started. Thus this application read the decoded serial BCD data from the PC COM port. There is several actions are predefined in this application for the TV remote buttons. When this application closes the PC Remote working also stops down.



7.8.1. Visual Basic

Visual Basic is a tool to develop Windows (Graphic User Interface - GUI) applications. The applications have a familiar appearance to the user. Visual Basic is event-driven, meaning code remains idle until called upon to respond to some event (button pressing, menu selection ...). Visual Basic is governed by an event processor. Nothing happens until an event is detected. Once an event is detected, the code corresponding to that event (event procedure) is executed. Program control is then returned to the event processor. Some Features of Visual Basic

Full set of objects - you 'draw' the application Lots of icons and pictures for your use Response to mouse and keyboard actions Clipboard and printer access Full array of mathematical, string handling, and

graphics functions Can handle fixed and dynamic variable and control

arrays Sequential and random access file support Useful debugger and error-handling facilities Powerful database access tools ActiveX support Package & Deployment Wizard makes distributing

your applications simple. From the development of Visual Basic there have been different versions of the software.We used the Visual Basic 6.0.some features of the version is listed below. Faster compiler New ActiveX data control object Allows database integration with wide variety of

applications New data report designer New Package & Deployment Wizard Additional internet capabilities.



8. PROGRAM VAR1 equ r7 ;Temporary Variable TEMP equ 10H ;Temp variable COUNT equ 11H ;Count ADDR equ 12H ;Device address CMD equ 13H ;Command TEMP1 equ 14H ;Temporary Variable 1 FLIP bit 00H ;Flip bit TOG bit 01H ;Temp bit for flip MODE bit 02H ;Mouse mode/Keyboard mode default:mouse VALID bit 03H ;Valid bit IR equ P3.3 ;IR Receiver connected to this pin org 00H ;Start of prog clr a mov r0,#7FH clrram: ;Clearing Internal RAM mov @r0,a djnz r0,clrram mov sp,#50H ;Stack Pointer setup mov TMOD,#20H ;Serial port setup mov SCON,#50H ;Receive enable mov TH1,#0FDH ;9600, 8-N-1 mov TL1,#0FDH clr TOG ;clear temp bit clr MODE ;Set the default mode setb TR1 ;Start serial clock main: jb IR,$ ;Wait for first bit mov VAR1,#255 ;3.024mS delay djnz VAR1,$ mov VAR1,#255 djnz VAR1,$ mov VAR1,#255 djnz VAR1,$ mov VAR1,#255



djnz VAR1,$ mov VAR1,#255 djnz VAR1,$ mov VAR1,#100 djnz VAR1,$ mov c,IR ;Read Flip bit mov FLIP,c clr A mov COUNT,#5 ;Count for address fadd: mov VAR1,#255 ;1.728mS delay for each bit djnz VAR1,$ mov VAR1,#255 djnz VAR1,$ mov VAR1,#255 djnz VAR1,$ mov VAR1,#4 djnz VAR1,$ mov c,IR rlc a djnz COUNT,fadd mov ADDR,A ;Save the address clr a mov COUNT,#6 ;Count for Command fcmd: mov VAR1,#255 ;1.728mS Delay for each bit djnz VAR1,$ mov VAR1,#255 djnz VAR1,$ mov VAR1,#255 djnz VAR1,$ mov VAR1,#4 djnz VAR1,$ mov c,IR rlc a djnz COUNT,fcmd mov TEMP,CMD ;Save the old command mov CMD,a ;Save the new command mov a,ADDR ;Cheack for valid address cjne a,#00,nvalid jb MODE,key ;Use mouse mode if Mode bit is 0



acall mouse ljmp main key: ;or keyboard mode if Mode bit is 1 acall keyboard nvalid: ljmp main mouse: ;Routine for Mouse operation mov a,CMD cjne a,#0CH,mskip mov a,TEMP cjne a,CMD,m_valid ret m_valid: clr a mov c,FLIP rlc a mov TEMP1,a clr a mov c,TOG rlc a cjne a,TEMP1,m_valid1 ret m_valid1: mov c,FLIP mov TOG,c mov a,CMD cjne a,#0CH,mskip mov a,#30H acall tx jnb RI,$ clr RI mov a,SBUF cjne a,#'m',keymode clr MODE ret keymode: setb MODE ret mskip:



cjne a,#01H,mskip1 acall chk_valid jb VALID,ok1 ret ok1: mov a,#31H acall tx ret mskip1: cjne a,#02H,mskip2 mov a,#32H acall tx ret mskip2: cjne a,#03H,mskip3 acall chk_valid jb VALID,ok2 ret ok2: mov a,#33H acall tx ret mskip3: cjne a,#04H,mskip4 mov a,#34H acall tx ret mskip4: cjne a,#05H,mskip5 mov a,#35H acall tx ret mskip5: cjne a,#06H,mskip6 mov a,#36H acall tx



ret mskip6: cjne a,#26H,mskip7 mov a,#37H acall tx ret mskip7: cjne a,#38H,mskip8 mov a,#38H acall tx ret mskip8: cjne a,#10H,mskip9 mov a,#37H acall tx ret mskip9: cjne a,#11H,mskip10 mov a,#38H acall tx mskip10: ret chk_valid: mov a,TEMP cjne a,CMD,ms_valid1 ret ms_valid1: clr a mov c,FLIP rlc a mov TEMP1,a clr a mov c,TOG rlc a cjne a,TEMP1,ms_valid clr VALID ret



ms_valid: mov c,FLIP mov TOG,c setb VALID ret keyboard: ;Routine for Keyboard operation mov a,TEMP cjne a,CMD,k_valid1 ret k_valid1: clr a mov c,FLIP rlc a mov TEMP1,a clr a mov c,TOG rlc a cjne a,TEMP1,k_valid ret k_valid: mov c,FLIP mov TOG,c mov a,CMD clr c cjne a,#7,chk chk: jnc greater add a,#30H acall tx ret greater: cjne a,#0CH,next mov a,#30H acall tx jnb RI,$ clr RI mov a,SBUF cjne a,#'m',keymode1 clr MODE ret



keymode1: setb MODE ret next: cjne a,#26H,next1 mov a,#37H acall tx ret next1: cjne a,#38H,next2 mov a,#38H acall tx ret next2: cjne a,#10H,next3 mov a,#37H acall tx ret next3: cjne a,#11H,next4 mov a,#38H acall tx ret next4: cjne a,#20H,next5 mov a,#36H acall tx ret next5: cjne a,#21H,next6 mov a,#35H acall tx ret next6: cjne a,#0DH,next7 mov a,#39H acall tx next7: ret



tx: ;Serial Transmit mov sbuf,a jnb TI,$ clr TI ret END



9. EVALUATION

APPLICATION PC remote control is used to control the computer as a wireless mouse. This remote can all multimedia operation in a computer like movie, music playing, volume control, forwarding, reverse, etc. It simply converts your PC into a multimedia PC. It can be further modified into do greater jobs in the computer like log off, stand by, restart, shut down etc.

ADVANTAGE This circuit is simple to use and efficient. It can be assembled with ease. It is cheap and hence and very economic. It is small in size and can be fixed just as a peripheral device. It gives a range of operation other than any PC remote available in the market. DISADVANTAGE The one and only one disadvantage is that less or more line of sight operation should be maintained to get easy functionality of this circuit.



10. PRINTED CIRCUIT BOARD

Components layout

PCB FABRICATION

Printed circuits boards play a vital role here in

determining the overall performance of electronic equipment .A

good PCB design ensures that the noise introduced as a result of

component placement and track layout is held within limits while

still providing components years of assembly maintenance and

performance reliability.

Where and Why are PCB’s used?

Printed circuits boards are used to route electric signals through

copper track which are firmly bonded to an Insulating base.



Advantages of PCB over common wiring are:

1. PCB’s are necessary for connecting a large number of

electronic components in a very small area with minimum

parasitic effects.

2. PCB’s are simulated with mass production with less chance of

writing error.

3. Small components are easily mounted.

4. Servicing is simplified.

The base materials used for PCB’s are glass epoxy, epoxy

paper, polyester etc. Copper foil used for copper clad is

manufactured by the process of electronic deposition .The

properties of copper foil are:

Thickness………………35µ meter

Thickness tolerance……+5 µ meter

Purity of Copper………99.8%

Resistivity at 20C…….0.1594

PREPARATION OF SINGLE SIDED PCB

In a single sided PCB the conductor tracks run only on

one side of copper clad board. Thus crossing of conductors is not

allowed. Base materials are selected according to application. It

is mechanically and chemically cleansed. Then the photo resist is

an organic solution which when exposed to light of proper

wavelength, changes their solubility in developer but after

exposure to light is not soluble. Laminate coating of photo resist

is done by (i)spray coating (ii)Dip coating (iii)Roller coating. The

coated copper clad and laminated film negative is kept in intimate



contact with each other.

The assembly is exposed to UV light and exposed board

is rinsed in the developer tank. Proper developer has to be used

for a particular photo resist and then the PCB is dyed in a tray.

The dye reveals the flux to be used for a particular photo resist.

Then the PCB is dyed in a tray. LAYOUT

The layout can be done either by hand or by using PCB

designing software like ORCAD or PROTEL. FABRICATION

The required circuit is designed and the layout of the circuit is

done on the component side as well as the copper clad side.

Spaces are provided for holes to insert the respective

components. Etch resistant ink coatings are given on the

interconnecting marks.

ETCHING

The copper clad PCB is etched with ferric chloride solution

containing a small amount of Hydro Chloric Acid for increasing

activeness of Ferric Chloride in etching. Wherever the varnish

coating is there the copper remains. Then it is washed with water

and Oxalic Acid DRILLING

The required holes are drilled using twist drill. Now the PCB is

complete and ready for soldering. SOLDERING



Soldering is the process of joining of two metals using an alloy

solder consisting of Tin and Lead (Sn-Pb). Tin determines the

melting whereas the Lead is used to reduce the cost. After the

PCB fabrication is done, the various components are arranged at

proper locations on the PCB and then the soldering is done.

All liquids consist of particles which attract each other. The

surface is always is trying to shrink and this is because of surface

tension. The principle behind soldering is that when liquid

particles are brought in contact with the walls of the solid surface,

it may happen that the solid attracts the liquid surface. This

property is called adhesive property. Care must be taken that the

melting point of solder is below that of the metal so that its

surface is melted without melting without the metal.

NEED FOR FLUX

During the soldering process the flux acts as a medium for

improving the degree of melting. The basic functions of flux are

mentioned below:

1. Removes oxide from the surface.

2. Assists the transfer of heat from the source to the joining and

provides a liquid cover including air gap.

3. Removal of residue after the completion of the soldering

operation.



PCB Layout



11. COST ESTIMATION

NO COMPONENTS SPECIFICATION QUANTITY COST

1 µC AT89C2051 1 NO 1X60.00 = 60.00

2 TRASFORMER 12V-0-12V,250mA 1 NO 1X65.00 = 65.00

3 IC MAX232 1NO. 1X25.00 = 25.00

4 RESISTORS 10kΩ

1 NO 1X00.25 = 00.25

5 CAPACITORS 10µF

33pF

100nF

4 NOS.

2 NOS.

1 NO

1X02.00 = 02.00

2X01.00=002.00

1X01.00 = 01.00

7 SENSOR TSOP1738 NO 1X16.00 = 16.00

9 DIODES 1N4007

6 NOS

6X01.00 = 06.00

11 REMOTE 1NO 1X80.00 = 80.00

12 XTAL

OSCILLATOR

11.0592MHz 1 NO. 1X10.00 = 10.00

13 CLADBOARD 6X4 INCHES 1 NO. 1X25.00 = 25.00

14 COPPER

ETCHANT

FERRIC

CHLORIDE

500 GRAM .50X138 = 69.00

TOTAL COST=361.25



12. CONCLUSION

With the little knowledge in electronics and computer programming we could make an application like

“PC CONTROLLED WITH TV REMOTE”

Our PC remote installation is simple. The circuit can easily connect to the DB9 PC COM port and the software can be installed in simple steps.

This circuit nowadays has high economical value. There are many PC Remote models are available in the market, and all those have a high cost. Other than the cost available models in the market are works in a short range, needs a Bluetooth module in the PC. Here our remote works with infrared signals and a range of approximately 10meters can be achieved without any difficulty.



13. REFERENCE

THE 8051 MICROCONTROLLER ARCHITECTURE, PROGRAMMING, AND APPLICATION : KENNETH J. AYALA

WWW.KEIL.COM PROGRAMMING WITH VISUAL BASIC 6.0

: MOHAMMED AZAM

SAMS TEACH YOURSELF VISUAL BASIC 6IN 21 DAYS : GREG PERRY

WWW.8051PROJECTS.COM

WWW.DATASHEETCATALOG.COM

WWW. SODOITYOURSELF.COM

WWW.ELECTRO-TECH-ONLINE.COM



14. DATASHEETS

©2001 Fairchild Semiconductor Corporation

www.fairchildsemi.com

Rev. 1.0.1

Features• Output Current up to 1A • Output Voltages of 5, 6, 8, 9, 10, 12, 15, 18, 24V • Thermal Overload Protection • Short Circuit Protection• Output Transistor Safe Operating Area Protection

DescriptionThe MC78XX/LM78XX/MC78XXA series of three terminal positive regulators are available in the TO-220/D-PAK package and with several fixed output voltages, making them useful in a wide range of applications. Each type employs internal current limiting,thermal shut down and safe operating area protection, making it essentially indestructible. If adequate heat sinkingis provided, they can deliver over 1A output current.Although designed primarily as fixed voltage regulators,these devices can be used with external components toobtain adjustable voltages and currents.

TO-220

D-PAK

1. Input 2. GND 3. Output

1

1

Internal Block Digram

MC78XX/LM78XX/MC78XXA3-Terminal 1A Positive Voltage Regulator

MC78XX/LM78XX/MC78XXA

2

Absolute Maximum Ratings

Electrical Characteristics (MC7805/LM7805)(Refer to test circuit ,0 C < TJ < 125 C, IO = 500mA, VI = 10V, CI= 0.33 F, CO= 0.1 F, unless otherwise specified)

Note:1. Load and line regulation are specified at constant junction temperature. Changes in Vo due to heating effects must be taken

into account separately. Pulse testing with low duty is used.

Parameter Symbol Value UnitInput Voltage (for VO = 5V to 18V)(for VO = 24V)

VIVI

3540

VV

Thermal Resistance Junction-Cases (TO-220) R JC 5 oC/WThermal Resistance Junction-Air (TO-220) R JA 65 oC/WOperating Temperature Range TOPR 0 ~ +125 oCStorage Temperature Range TSTG -65 ~ +150 oC

Parameter Symbol ConditionsMC7805/LM7805

UnitMin. Typ. Max.

Output Voltage VO

TJ =+25 oC 4.8 5.0 5.25.0mA Io 1.0A, PO 15WVI = 7V to 20V 4.75 5.0 5.25 V

Line Regulation (Note1) Regline TJ=+25 oCVO = 7V to 25V - 4.0 100

mVVI = 8V to 12V - 1.6 50

Load Regulation (Note1) Regload TJ=+25 oCIO = 5.0mA to1.5A - 9 100

mVIO =250mA to 750mA - 4 50

Quiescent Current IQ TJ =+25 oC - 5.0 8.0 mA

Quiescent Current Change IQIO = 5mA to 1.0A - 0.03 0.5

mAVI= 7V to 25V - 0.3 1.3

Output Voltage Drift VO/ T IO= 5mA - -0.8 - mV/ oCOutput Noise Voltage VN f = 10Hz to 100KHz, TA=+25 oC - 42 - V/Vo

RippleRejection RR f = 120HzVO = 8V to 18V 62 73 - dB

Dropout Voltage VDrop IO = 1A, TJ =+25 oC - 2 - VOutput Resistance rO f = 1KHz - 15 - mShort Circuit Current ISC VI = 35V, TA =+25 oC - 230 - mAPeak Current IPK TJ =+25 oC - 2.2 - A

MC78XX/LM78XX/MC78XXA

25

Mechanical DimensionsPackage

TO-220

Electrical and Electronics Mini Project Report on Control of Pc With Tv Remote Cusat University

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Transcript of Electrical and Electronics Mini Project Report on Control of Pc With Tv Remote Cusat University