joshi krunal 05ec46 report (1)

8/6/2019 Joshi Krunal 05ec46 Report (1)

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Charotar Institute of Technology-Changa Page 2


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ACKNOWLEDGEMENT

Any accomplishment requires the grace of God and the effort of many people .This endeavor ofmine would not have been possible without gracious help of many. During my training, I am in

debt by many great personalities and mentors at Automation engineers and at my college Citc.Following are few words to acknowledge my sincere thanks to all those who have understandand nurtured my needs.

I am grateful to Mr. Kanziya Director at Automation Engineers ( Former director at DoT)for allocating me this project under the esteemed guidance of Mr. Dharmendra Parmar

I am very much thankful to Prof. Hitesh Patel (Lecturer of Dept.), my projectguide for their foresight in giving this opportunity to develop the ideas presented here by doingthe project on Multi Channel Temperature Controller I am extremely thankful to Prof. Y PKosta, Principal Charotar Inst. Of Tech., Changa who gave me an opportunity to do this project.

I am thankful to Prof. Brijesh Shah, HOD E & C dept.; CITC, Changa, His kind attentionguidance and positive feedback have helped me a lot in the project.

Joshi Krunal K. (05\EC\46)Parekh Krunal S. (05/EC/53)


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ABSTRACT

The evolution in microprocessor & microcontroller so capacity & ability to get maximum workin new invited microprocessor & microcontroller is very impressive. Multi Channel Temperature

Controller is project that can Controls the temperature of 8 different Electrical furnaces. We getoutput on 7 segment card or computer terminal it is depend on project cost or requirement ofuser.


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TABLE OF CONTENTS

CHAP.NO.

CHAPTER PAGE NO.

Title page 2

College Certificate 3

Company Certificate 5

Acknowledgement 7

Abstract 8

1. Project Profile

1.1 Introduction1.2 Why this project???1.3 Project selection

121314

2. Hardware Design2.1 Block Diagram2.2 Description2.3 Circuit Diagram2.4 Printed circuit board(PCB)2.5 Component list2.6 Component study2.7 Sensor study2.8 Study of ADC2.9 Study of parallel to serial convertor2.10 Study of controller2.11 Study of relays

2.12 Study of optocoupler2.13 Transistor study

1618212225262628303134

3637

3. Software Design & Programming

3.1 Software development tool3.2 Flow Chart3.3 Program

404142

4. My Experience During Project 51


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5. User Manual

Application

Conclusion

535557

APPENDIX-1

y Datasheet 58

APPENDIX-2

y Bibliography 75


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LIST OF FIGURES

Figure 1: Block diagram of Temp. controller 18

Figure 2: Block diagram of 8 channel Temp. controller 19Figure 3: Circuit Diagram 23Figure 4: Top layer of Control card 24Figure 5: Top layer of Relay card. 25Figure 6: Bottom layer of Control card.. 26Figure 7: Bottom layer of Relay card

..... 26Figure 8: LM35. 30Figure 9: Block diagram of ADC 0808.. 31Figure 10: PIN Configuratrion of 74LS166.. 33Figure 11: Sugar Cube Relay.. 36Figure 12: Different types of Relays. 37

Figure 13: Optocoupler... 39Figure 14: Transistor Symbol.. 39Figure 15: BC 547 Transistor.. 40Figure 16: Flow Chart.. 43Figure 17: Hyper terminal... 55Figure 18: Hyper terminal

.... 56Figure 19: Hyper terminal. 56Figure 20: Infrared Communication. 57Figure 21: Temperature Controller. 57


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Figure 22: Application Temperature Controller.. 58Figure 23: Green House control.. 58Figure 24: Furnace Temp. Control

59Figure 25: PIN Configurations of AT 89S52........... 62Figure 26: Block diagram of ADC. 67Figure 27: PIN Out of ADC 0808. 67Figure 28: 74LS166 68Figure 29: Logic Diagram of 74LS166. 69

Figure 30: LM35 Temperature Sensor.. 70Figure 31: Temperature Sensor Circuit.. 71Figure 32: MAX 232.. 72Figure 33: Logic Diagram of MAX 232.. 73Figure 34: LM 555IC.. 75

LIST OF TABLES

Table 1: Component List................. ................... .................. ...................................................................... 27Table 2: Function Table of MAX 232 .................................................................... 73


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CHAPTER 1

PROJECT PROFILE.


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1.1 INTRODUCTION.

Multi channel Temperature controller is a system which can scan, detect and

Control the temperature of a multi channel furnace.This system can control the temperature iffurnaces temperature is going to Above the limit . It can stop the furnace and after some delay it

can restart the system. In our project the status of the system can be continuously monitored.We can also update the status on the internet so we can monitor from remote places.

A Temperature controller is an electronic instrument that record measurements

of temperature and control it as requirements. In this project the temperature of any instruments

which is to be controlled is interface with personal computer and showing its details on pc

screen.

The first step involves a sensor,which converts a physical temperature value to

the appropriate or proportional voltage or current value. There are many types of temperature

sensors. A temperature sensor is used to convert temp. value to electrical value.

This temp. control system based on the microcontroller. As our requirements wecan change the program and the control process. The microcontroller will perform some signal

processing on data , and depending on how it is programmed, may send resulting information

out to the network. The network interface block handles network transaction. Monitoring

interface program was implement as a software using visual c++.

This system is low cost, tiny and easy in implementation. The proposed

microcontroller based temperature controller system will be used in many different application to

monitor and collect specific types of information.


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1.2 WHY THIS PROJECT????

What we have learnt about power Generation. Power transmission, power distribution etc.. In

our previous semester from it we know that it is so much important to control the temperature of

boiler, furnace,Cooling tower, coal mills etc. So here the need of temperature controller is must.

We have got idea to make project on multi chan0nel temperature controller to control temp. of

more than one channel Together. we have tried to make a low cost project so it can be used in

power station, in chemical factory,in a.c. control etc..so many areas. In big industry we can

control temp. and also we can see status of temp. continuously. Here we are going to control

temperature of 8 furnaces.


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1.3 PROJECT SELECTION

Here we are in the last semester of engineering. so we have to make a project as a part

of our B.E. We want to make the best project for our career semester, which is going to give

direction to our future career. For this we have studied about so many project and topics to

make a practically implemented and useful project. After studying about so many projects

and seeing our capacity we have decided to make a project named Multi channel

temperature controller.

As this topic is related to so many industries and can be helpful to make system easier

and also can become a low cost system, We have decided to make this project. We can makea single channel to multichannel Controller but here we have made 8 channel temperature

controller to control temperature.


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CHAPTER 2

HARDWARE DESIGN..


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2.1 BLOCK DIAGRAM

ELECTRICAL

SIGNAL

FIG.1 BLOCK DIAGRAM OF TEMP. CONTROLLER

FURNACESENSOR

DISPLAY

SYSTEM

ANALOG TODIGITALCONVERTOR

PARALLELTO SERIALCONVERTOR

MICRO

CONTROLLERFURNACECONTROL


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FIG.2 BLOCK DIAGRAM OF 8 CHANNEL TEMP. CONTROLLER

1

2

3

4

5

6

7

8

AnalogTo

DigitalCNVERTOR

P

ARALLEL

To

SERI

AL

MicroCONTROLLER

F

URNESS

CONTROL

Display

Unit

D0

D1

D2

D3

D4

D5

D6

D7

ELECTRICAL SIGNAL

ELECTRICAL SIGNAL

ELECTRICAL SIGNAL

ELECTRICAL SIGNAL

ELECTRICAL SIGNAL

ELECTRICAL SIGNAL

ELECTRICAL SIGNAL

ELECTRICAL SIGNAL

CONTROL SIGNAL


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2.2 DESCRIPTION

The sensor detects the temperature signals coming from the furnace and convert them

into electrical signals. These electrical signals are send to the Analog to Digital

converter .Here analog data are converted into digital data.

These digital signals are send to the parallel to serial Converter for the serial transfer of data. The

serial Data output is send to the microcontroller as a input.

Microcontroller compares these incoming digital signals With the reference temperature

of the furnace which is Preset and microcontroller will take the appropriate Action

according to that. Microcontroller send the Control Signals to each furnace. Thus ,

furnaces temperature can be Controlled by Microcontroller.

There is a display unit also connected with microcontroller to which microcontroller

continuously send the status of the system and by this display unit we can monitor our

System continuously for all eight furnace.

To accurately control process temperature without extensive operator involvement, atemperature control system relies upon a controller, which accepts a temperature sensorsuch as a thermocouple or RTD as input. It compares the actual temperature to thedesired control temperature, or setpoint, and provides an output to a control element.

The following items should be considered when selecting a controller:

y Types of input sensor (thermocouple, RTD, or other)and temp. range.

y Types of output required (eletromech. Relay, analog output)

y Control algorithm needed (on-off, proportional, PID)

y Number and types of output (heat, cool, alarm, limit..)

The first step involves a sensor which converts a physical temperature variables to a

proportional voltage or current.


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The sensor outputs are in analog form when controller need input in digital form, so we

have use analog to digital convertor. Now the digital signal interrupt the controller and

according to given program controller will do some task in which it display measured

temperature on the pc screen.

Now we use Transistor here because we need sufficient current to turn on the relay. If the

temperature is above or below the required temperature which need to be maintain the

controller to turn on the relay.

Here in the project max 232 is used for serial data communication and it used to send the

data from controller to computer and connector is used to connect the max 232 and

computer.


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2.3 CIRCUIT DIAGRAM

FIG. 3 CIRCUIT DIAGRAM


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2.4 PRINTED CIRCUIT BOARD

There is mainly single sided and double sided PCB.

Here we use single sided PCB.

Top layer is known as component layer.

Silk screen layer is mounted on the top layer.

Top layer is shown as below in fig.

FIG. 4 TOP LAYER OF CONTROL CARD

There is masking on the PCB. Here green color indicates masking and yellow

color indicates non masking.

To prevent short circuit at the time of soldering we use masking.

Bottom layer is known as solder layer.


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At bottom layer there is tinning to prevent circuit from corrosion and for easy

soldering.

Tinning is the upper layer of the copper.

Bottom layer is shown as below in fig.

FIG. 5 TOP LAYER OF RELAY CARD

Here we use SMD (Surface Mount Device) component.

Mainly two advantage of SMD component.

1. It requires less space.

2. Because of resistance, capacitance cost down.

Material used for PCB is FR4 (Flame Retardant 4).

Length of PCB is 12 cm.

Width of PCB is 5.5 cm.

Thickness of PCB is 0.2 cm.


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FIG. 6 BOTTOM LAYER OF CONTROL CARD

FIG. 7 BOTTOM LAYER OF RELAY CARD


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2.5 COMPONENT LIST

y IC AT89s52 y MAX 232 IC

y ADC 0808 y Potentiometer(10k,10tone)

y IC 74LS166 y Transformer(12/0/12 , 1A)

y 555 Timer y Optocoupler

y LM 35 y Relay (single contact 12 v dc)

y

Transistor BC 547y

DB9s socket

y Diode (1N 4007) y 3 pin connector

y LM 7805 y 222 pf Capacitor

y Heat sink y Resistor (10 k)

y LEDs y Resistor (1 k)

y Push button switch y Resistor(470 E)

y Bug strip y Capacitor(1000uf /35 v )

y Pull up resistor y Capacitor(100uf /25 v )

y Capacitor(10uf /16 v ) y Capacitor(10uf /16 v )

y Capacitor(10uf /50 v ) y Connecter (10 pin)

y Capacitor(0.1uf) y Bulbs (60 watts)

y Bulb sockets y Crystal (11.0592MHZ)

TABLE-1


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2.6 COMPONENT STUDY

Here as a part of system planning I have to study about the component

of the project which are used in it. I have to make a list of components first and then I have to

compare many of the components and I have to decide which I should use. For this I have

studied about so many sensors, analog to digital converter, parallel to serial converter, most

of all microcontroller, timers, diodes, transistor, etc..and then I put useful components

according to my project requirements in my project.I have also study and then make power

supply for my project.here I have study about voltage regulator. Here I understand the need

of particular capacitor and resistor also. Here I also study about serial communication via

RS232. I have study and learn about closed loop system in detail and types of controller.

2.7 SENSOR STUDY

I can use so many sensors in this type of systems like

LM 35

LM 34

Pt 100

J type

K type

18520P

RTD

Thermocouple

In the industrial application we can use PT100 , RTD and Thermocouple etc.because in the industry there are very high temperature like 800C to 1500C. and for that

these sensors are used because they make variations on 50-60C. temperature. It is industrial

requirements.


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Because I have to make a model of system and I can create a temperature about

maximum 100C, I have choose LM 35 here. It makes variations even 5C temperature , so it

is suitable for my application.

LM 35:

Precision Centigrade Temperature Sensors

Description

The LM35 series are precision integrated-circuit temperature sensors, whose

output voltage is linearly proportional to the Celsius (Centigrade) temperature. The LM35

thus has an advantage over linear temperature sensors calibrated in Kelvin, as the user is

not required to subtract a large constant voltage from its output to obtain convenient

Centigrade scaling.

The LM35 does not require any external calibration or trimming to provide

typical accuracies of 1/4C at room temperature and 3/4C over a full -55 to +150C

temperature range. Low cost is assured by trimming and calibration at the wafer level.

The LM35s low output impedance, linear output, and precise inherent calibration make

interfacing to readout or control circuitry especially easy. It can be used with single

power supplies, or with plus and minus supplies.As it draws only 60 A from its supply,it has very low self heating, less than 0.1C in still air.

LM35 series is available packaged in hermetic TO-46 transistor

packages, while theLM35C, LM35CA, and LM35D are also available in the plastic TO-

92 transistor package. The LM35D is also available in an 8- lead surface mount small

outline package and a plastic TO-220 package.

Features

y Calibrated directly in Celsius (Centigrade)

y Linear + 10.0 mV/C scale factor

y 0.5C accuracy guaranteeable (at +25C)

y Rated for full -55 to +150C range


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y Suitable for remote applications

y Low cost due to wafer-level trimming

y Operates from 4 to 30 volts

y Less than 60 A current drain

y Low self-heating, 0.08C in still air

y Nonlinearity only 1/4C typical

y Low impedance output, 0.1 W for 1 mA load

FIG.8 LM 35

2.8 STUDY OF ADC

Typically, an ADC is an electronic device that converts an input

analog voltage (or current) to digital number proportional to the magnitude of the voltage

or current. However, some non-electronic or only partially electronic devices, such

as rotary encoders, can also be considered ADCs. The digital output may use different

coding schemes, such as binary, Gray code or two's complement binary.

After studying many types of analog to digital converter I have choose ADC 0808 in

my project because it has some advantages as under:

Features:

Easy interface to all microprocessors


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Operates ratiometrically or with 5 VDC or analog span adjusted voltage

reference.

No zero or full-scale adjust required.

8-channel multiplexer with address logic.

OV to 5V input range with single 5V power supply.

Outputs meet TTL voltage level specifications.

Standard hermetic or molded 28-pin DIP package.

28-pin molded chip carrier package.

ADCO8O8 equivalent to MM74C949

Resolution-8 Bits

Single Supply -5 VDC

Low Power -15 mW

Conversion Time -1OO ps

FIG. 9 BLOCK DIAGRAM OF ADC 0808


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2.9 STUDY OF PARALLEL TO SERIAL CONVERTER

Parallel to serial converter is a device which convert incoming parallel digital data

to serial data as output. Because we have limitation of microcontroller having only 40 pins, it

is not suitable to use 8 pin of microcontroller for incoming ADC signals. So here we use

parallel to serial converter between ADC and microcontroller . Using parallel to serial

converter we use only 3 pins of microcontroller for output of ADC .

Here we use 74LS166 parallel to serial converter for serially transmission of data.

It is a parallel load 8- bit shift register. Designed with all inputs buffered, the drive

requirements are lowered to one 54/74LS standard load.By utilizing input clamping diodes,switching transients are minimized and system design simplified.

The LS166 is a parallel-in or serial-in, serial-out shift register and has a

complexity of 77 equivalent gates with gated clock inputs and an overriding clear input.

The shift/load input establishes the parallel-in or serial-in mode. When high, this input

enables the serial data input and couples the eight flip-flops for serial shifting with each

clock pulse. Synchronous loading occurs on the next clock pulse when this is low and the

parallel data inputs are enabled. Serial data flow is inhibited during parallel loading.

Clocking is done on the low-to-high level edge of the clock pulse via a two

input positive NOR gate, which permits one input to be used as a clock enable or clock

inhibit function. Clocking is inhibited when either of the clock inputs are held

high,holding either input low enables the other clock input. This will allow the system

clock to be free running and the register stopped on command with the other clock input.

A change from low-to-high on the clock inhibit input should only be done when the clock

input is high. A buffered direct clear input overrides all other inputs, including the clock,

and sets all flip-flops to zero.

Synchronous Load

Parallel to Serial Conversion


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FIG. 10 PIN CONFIGURATION OF 74LS166

2.10 STUDY OF CONTROLLER

Types of temperature controller

y On-off controller

y Proportional controller

y PID controller]

y Depending upon the system to be controlled.

We have used here a on- off controller.

ON-OFF Controller :

y An on-off controller is the simplest form of temperature control device.

y The output from the device is either on or off, with no middle state.


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y An on-off controller will switch the output only when the temperature crosses the

set point.

y For the heating control, the output is on when the temperature is below the set

point an of above the set point.y Since the temperature crosses the set point to change the otput state, the process

temperature will be cycling continually,going from below set point to above, and

back below. In cases where this cycling occurs rapidly and to prevent damage to

contactors and valves, as an on-off differential, or hysteresis , is added to the

controller operations.

y This differential requires that the temperature exceeds set point by a certain

amount before the output will turn off or on again.

y This controller uses a latching relay, which must be manually reset, and is used to

shut down a process when a certain temperature is reached.

Features of ON-OFF Controller:

y Dual Outputs

y 4 programmable Lm 35 inputs

y reverse or direct control

y power option: 90 to 260 v ac and 10 to 32 v ac/dc

y easy 4 button set-up

y Hyper terminal display.

CRITERIA FOR CHOOSING A MICROCONTROLLER

The basic criteria for choosing a microcontroller suitable for the application are:

1) The first and foremost criterion is that it must meet the task at hand efficiently and

cost effectively. In analyzing the needs of a microcontroller-based project, it is seen

whether an 8- bit, 16-bit or 32-bit microcontroller can best handle the computing needs


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of the task most effectively. Among the other considerations in this category are:

(a) Speed: The highest speed that the microcontroller supports.

(b) Packaging: It may be a 40-pin DIP (dual inline package) or a QFP (quad flat

package), or some other packaging format. This is important in terms of space,

assembling, and prototyping the end product.

(c) Power consumption: This is especially critical for battery-powered products.

(d) The number of I/O pins and the timer on the chip.

(f) How easy it is to upgrade to higher performance or lower consumption versions.

(g) Cost per unit: This is important in terms of the final cost of the product in which a

microcontroller is used.

2) The second criterion in choosing a microcontroller is how easy it is to develop

products around it. Key considerations include the availability of an assembler,

debugger, compiler, technical support.

3) The third criterion in choosing a microcontroller is its ready availability in

needed quantities both now and in the future. Currently of the leading 8-bitmicrocontrollers, the

8051 family has the largest number of diversified suppliers. By supplier is meant a

producer besides the originator of the microcontroller. In the case of the 8051, this

has originated by Intel several companies also currently producing the 8051.

Thus the microcontroller AT89S52, satisfying the criterion necessary for the proposed

application is chosen for the task.


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2.11 STUDY OF RELAYS

A relay is an electrical switch that opens and closes under the control of

another electrical circuit. In the original form, the switch is operated by an

electromagnet to open or close one or many sets of contacts. It was invented by Joseph

Henry in 1835. Because a relay is able to control an output circuit of higher power than

the input circuit, it can be considered to be, in a broad sense, a form of an electrical

amplifier.

FIG. 11 SUGER CUBE RELAY

Despite the speed of technological developments, some products prove so

popular that their key parameters and design features remain virtually unchanged for

years. One such product is the sugar cube relay, shown in the figure above,

which has proved useful to many designers who needed to switch up to 10A, whilst

using relatively little PCB area.

Since relays are switches, the terminology applied to switches is also

applied to relays. A relay will switch one or more poles, each of whose contacts can be

thrown by energizing the coil in one of three ways:


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1.Normally - open (NO) contacts connect the circuit when the relay is activate d; the

circuit is disconnected when the relay is inactive. It is also called a FORM A contact

or make contact.

2.Normally - closed (NC) contacts disconnect the circuit when the relay is activated ;

the circuit is connected when relay is inactive. It is also called FORM B

contact or break contact

3.Change-over or double-throw contacts control two circuits ; one normally open

contact and one normally closed contact with a common terminal. It is also called

a Form C transfer contact.

The following types of relays are commonly encountered:

FIG.12 DIFFERENT TYPE OF RELAY

SPST - Single Pole Single Throw: These have two terminals which can beconnected or disconnected. Including two for the coil, such a relay has four

terminals in total. It is ambiguous whether the pole is normally open or

normally closed. The terminology "SPNO" and "SPNC" is sometimes used to

resolve the ambiguity.

SPDT - Single Pole Double Throw: A common terminal connects to either


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of two others. Including two for the coil, such a relay has five terminals in

total.

DPST - Double Pole Single Throw: These have two pairs of terminals.

Equivalent to two SPST switches or relays actuated by a single coil. Including

two for the coil, such a relay has six terminals in total. It is ambiguous whether

the poles are normally open, normally closed, or one of each.

DPDT - Double Pole Double Throw: These have two rows of change-over

terminals. Equivalent to two SPDT switches or relays actuated by a single coil.

Such a relay has eight terminals, including the coil.

QPDT - Quadruple Pole Double Throw: Often referred to as Quad Pole

Double Throw, or 4PDT. These have four rows of change-over terminals.

Equivalent to four SPDT switches or relays actuated by a single coil, or two

DPDT relays. In total, fourteen terminals including the coil.

2.12 STUDY OF OPTOCOUPLER

An opto-isolator (oroptical isolator, optical coupling

device, optocoupler,photocoupler, orphotoMOS) is a device that uses a

short optical transmission path to transfer anelectronic signal between elements of

a circuit, typically a transmitter and a receiver, while keeping them electrically isolated

since the electrical signal is converted to a light beam, transferred, then converted back to

an electrical signal, there is no need for electrical connection between the source and

destination circuits. Isolation between input and output is rated at 7500 Volt peak for 1

second for a typical component costing less than 1 US$ in small quantities.

The opto-isolator is simply a package that contains both an infrared light-emitting

diode (LED) and a photodetector such as a photosensitive silicon diode, transistor

Darlington pair, or silicon controlled rectifier (SCR). The wave-length responses of the

two devices are tailored to be as identical as possible to permit the highest measure of


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coupling possible. Other circuitryfor example an output amplifiermay be integrated

into the package. An opto-isolator is usually thought of as a single integrated package,

but opto-isolation can also be achieved by using separate devices.

Digital opto-isolators change the state of their output when the input statechanges; analog isolators produce an analog signal which reproduces the input.

FIG.13 OPTOCOUPLER

2.13 TRANSISTOR STUDY

The BC547 is an NPN Epitaxial Silicon Transistor. The BC547 transistor is

a general-purpose transistor in a small plastic packages. It is used in general-purpose

switching and amplification BC847/BC547 series 45 V, 100 mA NPN general-purpose

transistors. The BC547 transistor is an NPN Epitaxial Silicon Transistor. The BC547

transistor is a general-purpose transistor in a small plastic packages. It is used in general-

purpose switching and amplification BC847/BC547 series 45 V, 100 mA NPN general-

purpose transistors.

FIG. 14 TRANSISTOR SYMBOL


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The BC547 transistor is an NPN bipolar transistor, in which the letters

"N" and "P" refer to the majority charge carriers inside the different regions of the

transistor. Most bipolar transistors used today are NPN, because electron mobility is

higher than hole mobility in semiconductors, allowing greater currents and faster

operation. NPN transistors consist of a layer of P-doped semiconductor (the "base")

between two N-doped layers. A small current entering the base in common-emitter mode

is amplified in the collector output. In other terms, an NPN transistor is "on" when its

base is pulled high relative to the emitter. The arrow in the NPN transistor symbol is on

the emitter leg and points in the direction of the conventional current flow when the

device is in forward active mode. One mnemonic device for identifying the symbol for

the NPN transistor is "not pointing in." An NPN transistor can be considered as two

diodes with a shared anode region. In typical operation, the emitter base junction is

forward biased and the base collector junction is reverse biased. In an NPN transistor, for

example, when a positive voltage is applied to the base emitter junction, the equilibrium

between thermally generated carriers and the repelling electric field of the depletion

region becomes unbalanced, allowing thermally excited electrons to inject into the base

region. These electrons wander (or "diffuse") through the base from the region of high

concentration near the emitter towards the region of low concentration near the collector.

The electrons in the base are called minority carriers because the base is doped p-type

which would make holes the majority carrier in the base

FIG. 15 BC547 TRANSISTOR


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CHAPTER 3

SOFTWARE DESIGN.

&

PROGRAMMING


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3.1 SOFTWARE DEVELOPMENT TOOL

KEIL Software(Vision3 IDE):

The KEIL C51 Cross Compiler is an ANSI C compiler that was written specifically to

generate fast, compact code for the 8051 microcontroller family. The C51 Compiler

generates object code that matches the efficiency and speed of assembly programming.

Using a high-level language like C has many advantages over assembly language

programming:

1. Knowledge of the processor instruction set is not required.

2. Details like register allocation and addressing of the various memory types and

data types are managed by the compiler.

3. Programs get a formal structure (which is imposed by the C programming

language) and can be divided into separate functions. This contributes to source

code reusability as well as better overall application structure.

4. The ability to combine variable selection with specific operations improves

program readability.

5. Programming and program test time is drastically reduced.

6. The C run-time library contains many standard routines such as: formatted output,

numeric conversions, and floating point arithmetic.

7. Existing program parts can be more easily induced into new programs because of

modular program construction techniques.


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3.2 FLOW CHART

What is Flow Chart????

A flowchart is a common type of diagram, that represents

an algorithm or process, showing the steps as boxes of various kinds, and their

order by connecting these with arrows. This diagrammatic representation can give

a step-by-step solution to a given problem. Data is represented in these boxes, and

arrows connecting them represent flow / direction of flow of data. Flowcharts are

used in analyzing, designing, documenting or managing a process or program in

various fields.There are two commonly used tools to help to document program logic (the

algorithm). These are flowcharts and Pseudocode. Some of the common symbols

used in flowcharts are shown below:

FIG. 16 FLOW CHART


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3.3 PROGRAM

#include

code unsigned char ssd[10]="0123456789";

void chl_increment();

void chl_decrement();

void ref_increment();

void ref_decrement();

void refreshdis();

void delay(unsigned int millisec);

void microdelay();

void inputting();

void controll();

unsigned char n;

unsigned char chNum=0,ch=0;

unsigned char ref[8]={25,25,25,25,25,25,25,25};

unsigned char refMSDdis;

unsigned char refLSDdis;

unsigned char chl_temp[8]={26,24,26,24,26,24,26,24};

unsigned char tempMSDdis,tempLSDdis;

sbit A0=0xA0; //A0,A1,A2 are addresses of analog chl of ADC0808 sbit

A1=0xA1; //pin P2.1

sbit A2=0xA2; //pin P2.2

sbit ALE=0xA3; //address lach enable pin P2.3

sbit START=0xA4; //start of a to d conversion pin P2.4

sbit SH_LD=0xA5; //output enable pin P2.5

sbit CLK=0xA6; //clock to shift data into controller pin P2.6

sbit DATA=0xA7; //data input pin P2.7


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sbit EOC=0x84;

unsigned char chl_count,variabledelay;

bit cyclicdis;

void main()

{

TCON=0x40; //timer1 enable to run

TMOD=0X20; //timer1 in mode2

TH1= -3; //set baud rate 9600

SCON=0x50; //8-bit UART;baud variable

while(1)

{

/*codes for scaning of ADC .scan all the 8-chl temp. put the

datas in chl_temp[8] refresh the display.*/

for(chl_count=0;chl_count


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cyclicdis=1;

if(n==0xF3) //1111 0011 press both K-3&K-4

cyclicdis=0;

refreshdis();

delay(variabledelay);

controll(); //controll the relays

} //end of while(1)

} //end of main()

void chl_increment()

{

chNum++;

ch=chNum%8; //to obtain chdata between 0 thro7

refreshdis();

delay(200);

}

void chl_decrement()

{

chNum--;

ch=chNum%8;

refreshdis();

delay(200);

}

void ref_increment()

{

ref[ch]++;


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refreshdis();

delay(200);

}

void ref_decrement()

{

ref[ch]--;

refreshdis();

delay(200);

}

void refreshdis()

{

if(cyclicdis==1)

{

chNum++;

ch=chNum%8;

delay(200);}

refMSDdis=ref[ch]/10; //int/int=int

refLSDdis=ref[ch]%10;

tempMSDdis=chl_temp[ch]/10;

tempLSDdis=chl_temp[ch]%10;

SCON=0x00;

SBUF=ssd[ch];


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while(TI==0){}

TI=0;

SBUF=ssd[refMSDdis];

while(TI==0){}

TI=0;

SBUF=ssd[refLSDdis];

while(TI==0){}

TI=0;

SBUF=ssd[tempMSDdis];

while(TI==0){}

TI=0;

SBUF=ssd[tempLSDdis];

while(TI==0){}

TI=0;

}

void delay(unsigned int millisec)

{

unsigned int loopcount;for(loopcount=0;loopcount


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void microdelay()

{

unsigned char dummy1,dummy2;

dummy1=9;

dummy2=dummy1/2;

}

void inputting()

{ //LSB is entered first

unsigned char buffer,i,sample;

unsigned char

mask0[8]={0xFE,0xFD,0xFB,0xF7,0xEF,0xDF,0xBF,0x7

F};

unsigned char

mask1[8]={0x01,0x02,0x04,0x08,0x10,0x20,0x40,0x8

0};

SH_LD=1;EOC=1; //preparing P0_4 for input

DATA=1;

P2=P2|chl_count;//outpiting chl add. to ADC 0000 0000

ALE=0;

START=0;

ALE=1; //address latch to ADC

microdelay();START=1; //start 'a to d' conversion

microdelay(); //allow delay

ALE=0;

START=0;


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while(EOC==1)

{;}

while(EOC==0)

{;}

CLK=0;

SH_LD=0; //loading of all tjhe 8 bits into IC166

delay(1);

CLK=1; //parallel loading&shifting the bit into controller

delay(0);

SH_LD=1; //shifting of bits enabled

buffer=0x00;

for(i=0;i


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void controll()

{

unsigned char i;

unsigned char

mask0[8]={0xFE,0xFD,0xFB,0xF7,0xEF,0xDF,0xBF,0x7F};

unsigned char

mask1[8]={0x01,0x02,0x04,0x08,0x10,0x20,0x40,0x80};

for(i=0;i


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CHAPTER 4

MY EXPERIENCE DURING

PROJECT.


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4.1 MY EXPERIENCE DURING PROJECT

It is the first time We have got chance to make a project which can be

useful to industry and have a chance to learn industrial working. It was really a very good

experience for us. At the starting time of project we had no idea and no knowledge about

practical work in the engineering field.

Working on the project we have learnt so much about practical

applications and doing project We have learn soldering, knowledge about many

components , PCB designing and so many things. During this project sometimes we have

made mistakes also. But because of the mistakes we have learnt so much. And had a

experience to work in a group.

First we have made my circuit on GPB and after successfully running of my

circuit we have designed PCB.

During soldering we burnt twice but gradually we became good in soldering and

make my designed PCB with clean soldering work.

In power supply unit, we made capacitor power supply but were not reliable in

little bit fluctuation. So, we made bridge rectifier power supply, which is more

compatible.

During project work we have learnt about different types of capacitors and

resistors.

After completing hardware we have tested the whole circuit and make corrections.

During testing sometimes we could not find the trouble. Even sometime we have

spent whole day to shoot trouble.

First we give the output of ADC directly to the microcontroller, but we found thatit consume 8 pin of microcontroller, then we decide to use parallel to serial

converter between them.

During making report of my project we have learnt about so much tiny things

about project.


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we have broken once leg of IC in mounting process then solder it and make

testing.

During making model we have learnt to mount bulb socket on acralic plate.

So much things are there which we have learnt during this project.


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CHAPTER 5

USERMANUAL

&

APPLICATION

&

CONCLUSION


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5.1 USER MANUAL

First mount the all ICs on the IC socket on PCB of control card.

Make sure the all connection are correct and there is no short of wires.

Mount all bulbs on the bulb holders.

Give the power supply to the bulbs.

Make sure that the power supply of control card work properly and reach the

power to all components.

Make sure sensors are connected properly with temperature device.

Using multimeter check pins of ADC if signals reach there or not.

Same way check IC 74LS166.

You have to also check out microcontroller pins and connections.

Make sure the relay card has proper connection.

Using multimeter check the IC MAX232.

Connect PC and DBS-9 socket via serial com cable.

Now in your PC follow the following steps.

Start Program Accessories communication Hyper terminal

FIG 17 HYPER TERMINAL


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FIG 18 HYPER TERMINAL

FIG. 19 HYPER TERMINAL

You can follow the upper steps and get the hyper terminal screen where you can

see the output.

If you want to see the status of each furnace individual increment or decrement

the channel number from the control card by push buttons K1 and K2

respectively.

If you want to see cyclic display push the switch K1 , K2 together.

You can also set the reference temperature as per your need by push button switch

K3 and K4.it can increment or decrement the reference temperature.

If the circuit not giving the output check the all connections and shoot the trouble.

Check out the output pin of every IC using multimeter.


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5.2 APPLICATIONS AND FUTURE EXPANSION

Low-cost Program Control of Industrial Furnaces.

Improves Control Performance in Hydraulic Control of Metal Processing

Machines and Other Equipment

Ideal for High-precision Testing Equipment for Automotive Parts

Easy Temperature Setting with Infrared Communications Port on Front

Panel.

FIG 20 INFRARED COMMUNICATION

Solves Problems in Electronic Component Assembly

Ideal for Increasing the Control Performance of Industrial Hot Air Blowers

Multi-loop Control with a Single Temperature Controller

FIG. 21 TEMP.CONTROLLER

High Resolution Temperature Measurement

Temperature Control on Bonding, Evaporation and Coil Winding Equipment

Repeated Temperature Fluctuation Control in Furnace Test Equipment


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Higher Efficiency for Bread Baking Process

Automated Temperature Adjustments for Furnace

Turbine Power Generation Control

Cooling Water Control for a Spindle Motor

Uses a Master Temperature Controller to Change Set Value of Other

Air Conditioning Temperature Control

Multiple Temperature Control of Food Processing Equipment

Furnace Temperature Control.

FIG. 24 FURNACE TEMP.CONTROL

5.3 CONCLUSION

Making this project we have understood and realize the need of single

channel or multi channel temperature controller in the industrial application. It is very

useful project at the industrial level and we can use it for the different purpose by

modifying it.

Generally, multi channel temperature controller is used in power plants ,

furnaces, boiler , ovens, air conditioners, green houses, refrigerator and many more. Its

future expansion is also wide.


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APPENDIX-1

DATASHEETS


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A1.1 AT89S52

Features:

Compatible with MCS-51 Products

8K Bytes of In-System Programmable (ISP) Flash Memory

Endurance: 1000 Write/Erase Cycles

4.0V to 5.5V Operating Range

Fully Static Operation: 0 Hz to 33 MHz

Three-level Program Memory Lock

256 x 8-bit Internal RAM

32 Programmable I/O Lines

Three 16-bit Timer/Counters

Eight Interrupt Sources

Full Duplex UART Serial Channel

Low-power Idle and Power-down Modes

Interrupt Recovery from Power-down Mode

Watchdog Timer

Dual Data Pointer

Power-off Flag

Description:

The AT89S52 is a low-power, high-performance CMOS 8-bit

microcontroller with 8K bytes of in-system programmable Flash memory. The device is

manufactured using Atmels high-density nonvolatile memory technology and is

compatible with the industry- standard 80C51 instruction set and pinout. The on-chip

Flash allows the program memory to be reprogrammed in-system or by a conventional

nonvolatile memory programmer. By combining a versatile 8-bit CPU with in-system


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programmable Flash on a monolithic chip, the Atmel AT89S52 is a powerful

microcontroller which provides a highly-flexible and cost-effective solution to many

embedded control applications. The AT89S52 provides the following standard features:

8K bytes of Flash, 256 bytes of RAM, 32 I/O lines, Watchdog timer, two data pointers,

three 16-bit timer/counters, a six-vector two-level interrupt architecture, a full duplex

serial port, on-chip oscillator,and clock circuitry. In addition, the AT89S52 is designed

with static logic for operation down to zero frequency and supports two software

selectable power saving modes. The Idle Mode stops the CPU while allowing the RAM,

timer/counters, serial port, and interrupt system to continue functioning. The Power-down

mode saves the RAM contents but freezes the oscillator, disabling all other chip functions

until the next interrupt or hardware reset.


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FIG 25 PIN CONFIGURATION OF AT 89S52

Pin Description:

VCC

Supply voltage.

GND

Ground.

Port 0

Port 0 is an 8-bit open drain bidirectional I/O port. As an output port, each pin

can sink eight TTL inputs. When 1s are written to port 0 pins, the pins can be used as

highimpedance inputs. Port 0 can also be configured to be the multiplexed loworderaddress/data bus during accesses to external program and data memory. In this mode, P0

has internal pullups. Port 0 also receives the code bytes during Flash programming and

outputs the code bytes during program verification.

External pullups are required during program verification.

Port 1

Port 1 is an 8-bit bidirectional I/O port with internal pullups. The Port 1 output

buffers can sink/source four TTL inputs. When 1s are written to Port 1 pins, they are

pulled high by the internal pullups and can be used as inputs. As inputs, Port 1 pins that

are externally being pulled low will source current (IIL) because of the internal pullups.

In addition, P1.0 and P1.1 can be configured to be the timer/counter 2 external count

input (P1.0/T2) and the timer/counter 2 trigger input (P1.1/T2EX), respectively, as shown

in the following table. Port 1 also receives the low-order address bytes during Flash

programming and verification.

Port Pin Alternate Functions

P1.0 T2 (external count input to Timer/Counter 2), clock-out

P1.1 T2EX (Timer/Counter 2 capture/reload trigger

and direction control)

P1.5 MOSI (used for In-System Programming)

P1.6 MISO (used for In-System Programming)


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P1.7 SCK (used for In-System Programming)

read strobe)

Port 2




are externally being pulled low will source current (IIL) because of the internal pullups.

Port 2 emits the high-order address byte during fetches from external program memory

and during accesses to external data memory that use 16-bit addresses (MOVX @

DPTR). In this application, Port 2 uses strong internal pull-ups when emitting 1s. During

accesses to external data memory that use 8-bit addresses (MOVX @ RI), Port 2 emits

the contents of the P2 Special Function Register. Port 2 also receives the high-order

address bits and some control signals during Flash programming and verification.

Port 3




are externally being pulled low will source current (IIL) because of the pullups. Port 3

also serves the functions of various special features of the AT89S52, as shown in the

following table. Port 3 also receives some control signals for Flash programming and

verification.

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)

P3.6 WR (external data memory write strobe)

P3.7 RD (external data memory


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RST

Reset input. A high on this pin for two machine cycles while the oscillator is

running resets the device. This pin drives High for 96 oscillator periods after the

Watchdog times out. The DISRTO bit in SFR AUXR (address 8EH) can be used to

disable this feature. In the default state of bit DISRTO, the RESET HIGH out feature is

enabled.

ALE/PROG

Address Latch Enable (ALE) is an output pulse for latching the low byte of the

address during accesses to external memory. This pin is also the program pulse input

(PROG) during Flash programming. In normal operation, ALE is emitted at a constant

rate of 1/6 the oscillator frequency and may be used for external timing or clocking

purposes. Note, however, that one ALE pulse is skipped during each access to external

data memory. If desired, ALE operation can be disabled by setting bit 0 of SFR location

8EH. With the bit set, ALE is active only during a MOVX or MOVC instruction.

Otherwise, the pin isweakly pulled high. Setting the ALE-disable bit has no effect if the

microcontroller is in external execution mode.

PSEN

Program Store Enable (PSEN) is the read strobe to external program memory.

When the AT89S52 is executing code from external program memory, PSEN is activated

twice each machine cycle, except that two PSEN activations are skipped during each

access to external data memory.

EA/VPP

External Access Enable. EA must be strapped to GND in order to enable the

device to fetch code from external program memory locations starting at 0000H up to

FFFFH. Note, however, that if lock bit 1 is programmed, EA will be internally latched on

reset. EA should be strapped to VCC for internal program executions. This pin also

receives the 12-volt programming enable voltage (VPP) during Flash programming.

XTAL1


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Input to the inverting oscillator amplifier and input to the internal clock operating

circuit.

XTAL2 : Output from the inverting oscillator amplifier

A1.2 ADC 0808

General Description

The ADC0808, ADC0809 data acquisition component is a

monolithic CMOS device with an 8-bit analog-to-digital converter, 8-channel multiplexer

and microprocessor compatible control logic. The 8-bit A/D converter uses successive

approximation as the conversion technique. The converter features a high impedance

chopper stabilized comparator, a 256R voltage divider with analog switch tree and

successive approximation register. The 8-channel multiplexer can directly access any of

8-single-ended analog signals. The device eliminates the need for external zero and

fullscale adjustments. Easy interfacing to microprocessors is provided by the latched and

decoded multiplexer address inputs and latched TTL TRI-STATE outputs.

The design of the ADC0808, ADC0809 has been optimized by incorporating the

most desirable aspects of several A/D conversion techniques. The ADC0808, ADC0809

offers high speed, high accuracy, minimal temperature dependence, excellent long-term

accuracy and repeatability, and consumes minimal power. These features make this

device ideally suited to applications from process and machine control to consumer and

automotive applications. For 16- channel multiplexer with common output (sample/hold

port) see ADC0816 data sheet. (See AN-247 for more information.)

Features

y Easy interface to all microprocessors

y Operates ratiometrically or with 5 VDC or analog span

adjusted voltage reference.

y No zero or full-scale adjust required

y 8-channel multiplexer with address logic.

y 0V to 5V input range with single 5V power supply.


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y Outputs meet TTL voltage level specifications.

y Standard hermetic or molded 28-pin DIP package.

y 28-pin molded chip carrier package.

Key Specifications

y Resolution 8 Bits.

y Total Unadjusted Error g(/2 LSB and g1 LSB.

y Single Supply 5 VDC.

y Low Power 15 Mw.

y Conversion Time 100 ms

FIG 26 BLOCK DIAGRAM OF ADC

FIG 27 PIN OUT OF

ADC 0808


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A1.3 74LS166

8-BIT SHIFT REGISTERS

FIG. 28 74LS166

The SN54L/74LS166 is an 8-Bit Shift Register. Designed with all inputs buffered,

the drive requirements are lowered to one 54/74LS standard load. By utilizing input

clamping diodes, switching transients are minimized and system design simplified. The

LS166 is a parallel-in or serial-in, serial-out shift register and has a complexity of 77

equivalent gates with gated clock inputs and an overriding clear input. The shift/load

input establishes the parallel-in or serial-in mode. When high, this input enables the

serial data input and couples the eight flip-flops for serial shifting with each clock pulse.

Synchronous loading occurs on the next clock pulse when this is low and the parallel data

inputs are enabled. Serial data flow is inhibited during parallel loading. Clocking is done

on the low-to-high level edge of the clock pulse via a two input positive NOR gate, which

permits one input to be used as a clock enable or clock inhibit function. Clocking is

inhibited when either of the clock inputs are held high, holding either input low enables


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the other clock input. This will allow the system clock to be free running and the register

stopped on command with the other clock input. A change from low-to-high on the clock

inhibit input should only be done when the clock input is high. A buffered direct clear

input overrides all other inputs, including the clock, and sets all flip-flops to zero.


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FIG. 29 LOGIC DIAGRAM

A1.4 LM 35

National Semiconductors LM35 IC has been used for sensing the

temperature. It is an integrated circuit sensor that can be used to measure temperature

with an electrical output proportional to the temperature (in oC). The temperature

can be measured more accurately with it than using a thermistor. The sensor circuitry

is seale and not subject to oxidation, etc.

FIG.30 LM35 TEMPERATURE SENSOR

General Description

The LM35 series are precision integrated-circuit temperature sensors, whose output

voltage is linearly proportional to the Celsius (Centigrade) temperature. The LM35 thus has

an advantage over linear temperature sensors calibrated in Kelvin, as the user is not

required to subtract a large constant voltage from its output to obtain convenient Centigrade

scaling. The LM35 does not require any external calibration or trimming to provide typical

accuracies of 1/4C at room temperature and 3/4C over a full -55 to +150C

temperature range. Low cost is assured by trimming and calibration at the wafer level. The

LM35s low output impedance, linear output, and precise inherent calibration make

interfacing to readout or control circuitry especially easy. It can be used with single power

supplies, or with plus and minus supplies. As it draws only 60 A from its supply, it has


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very low self-heating, less than 0.1C in still air. The LM35 is rated to operate over a -55

to +150C temperature range, while the LM35C is rated for a -40 to +110C range (-10

with improved accuracy). The LM35 series is available packaged in hermetic TO-46

transistor packages, while the LM35C, LM35CA, and LM35D are also available in the

plastic TO-92 transistor package. The LM35D is also available in an 8-lead surface mount

small outline package and a plastic TO-220 package.

Features:

Calibrated directly in Celsius (Centigrade)

Linear + 10.0 mV/C scale factor

0.5C accuracy guaranteed (at +25C)

Rated for full 55 to +150C range

Suitable for remote applications

Low cost due to wafer-level trimming

Operates from 4 to 30 volts

Less than 60 A current drain.


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FIG.31 TEMPERATURE SENSOR CIRCUIT

A1.5 MAX 232

DUAL EIA-232 DRIVERS/RECEIVERS

y Operate With Single 5-V Power Supply

yOperate Up to 120 kbit/s

y Two Drivers and Two Receivers

y30-V Input Levels

y Low Supply Current . . . 8 mA Typical

yDesigned to be Interchangeable With

Maxim MAX232

yESD Protection Exceeds JESD 22

y 2000-V Human-Body Model (A114-A)

yApplications

TIA/EIA-232-F

Battery-Powered Systems

Terminals

Modems

Computers


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FIG 32 MAX 232

TABLE 2 FIG 33 LOGIC DIAGRAM

DESCRIPTION:

The MAX232 is an integrated circuit that converts signals from an RS-232 serial

port to signals suitable for use in TTL compatible digital logic circuits. The MAX232 is a

dual driver/receiver and typically converts the RX, TX, CTS and RTS signals. The

drivers provide RS-232 voltage level outputs (approx. 7.5 V) from a single + 5 V

supply via on-chip charge pumps and external capacitors. This makes it useful for

implementing RS-232 in devices that otherwise do not need any voltages outside the 0 V

to + 5 V range, as power supply design does not need to be made more complicated just

for driving the RS-232 in this case. The receivers reduce RS-232 inputs (which may be as

high as 25 V), to standard 5 V TTL levels. These receivers have a typical threshold of

1.3 V, and a typical hysteresis of 0.5 V.

The later MAX232A is backwards compatible with the original MAX232 but

may operate at higher baud rates and can use smaller external capacitors 0.1 F in place


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of the 1.0 F capacitors used with the original device. The newer MAX3232 is also

backwards compatible, but operates at a broader voltage range, from 3 to 5.5V.


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A1.6 LM555

General Description

The LM555 is a highly stable device for generating accurate time delays or

oscillation. Additional terminals are provided for triggering or resetting if desired. In the

time delay mode of operation, the time is precisely controlled by one external resistor and

capacitor. For astable operation as an oscillator, the free running frequency and duty

cycle are accurately controlled with two external resistors and one capacitor. The circuit

may be triggered and reset on falling waveforms, and the output circuit can source or sink

up to 200mA or drive TTL circuits.

Features

y Direct replacement for SE555/NE555

y Timing from microseconds through hours

y Operates in both astable and monostable modes

y Adjustable duty cycle

y Output can source or sink 200 Ma.

y Output and supply TTL compatible

y Temperature stability better than 0.005% per C

y

Normally on and normally off outputy Available in 8-pin MSOP package.

y

Applications

y Precision timing

y Pulse generation

y Sequential timing

yTime delay generation

y Pulse width modulation

y Pulse position modulation

y Linear ramp generator

FIG 34 LM 555 IC


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APPENDIX-2

BIBLIOGRAPHY.....


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A2.1 BOOKS

INDUSTRIAL INSTRUMENTATION AND CONTRO by S.K. SINGH

Publication: TATA MCGRAW HILL

FEEDBACK CONTROL SYSTEM by R.A.BARAPATE AND BHIDE

Publication : Tech-Max Publication

ELECTRONIC DEVICE AND CICUIT THEORY by R.L.BOYLESTAD

Publication : Prentice- Hall India

A2.2 WEBSITES

www.wikipedia.com

www.alldatasheets.com

www.keil.com

joshi krunal 05ec46 report (1)

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