Smoke Detector Using Zigbee

7/28/2019 Smoke Detector Using Zigbee

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ORGANIZATIONAL PROFILE

The National Small Industries Corporation Limited (NSIC) was established in

1955 by the Government of India with a view to promote, aid and foster the growth of Small

Industries in the country. NSIC continues to remain at the forefront, with it's various programs

and projects, to assist the small-scale sector in the country.

Over a period of four decades of this rescission, growth and development of

small-scale sector, it has proved its strength within the country and abroad dynamically, showing

its progressive attitude towards modernization, up gradation of technology, quality

consciousness, strengthening linkages with large and medium scale enterprises and boosting

exports of products from Small Enterprises. The small-scale sector continues to remain an

important instrument for enterprise-building, dispersal of industries for even regional economic

development and employment generation. NSIC has been successfully able to plan its assigned

role in this endeavor.

Due to changed industrial scenario and gradual globalization of the economy, small-scale

sector has to face stiff competition as the insulated and protected market conditions are no more

going to be available to it. To enable the small-scale industry to meet this challenge, NSIC has

already initiated various steps so that SSI's can play their due role, even during polarization of

various economic forces.

A SPECTRUM OF ACTIVITIES

NSIC provides diversified support through its wide spectrum of programs to TSC to cater

to their different needs related to multi-products and multi-locations markets. It has adopted a

multi-pronged approach to effectively serve the various needs of TSC. Assistance by NISC to

Small Scale Units to sell their goods and services to government departments and agencies,

through 'Single Point Registration Scheme', provides a vast marketing opportunity.

The corporation also arranges indigenous as well as imported raw materials and parts

to ensure that the production cycle of SSI's continues without break and they are able to produce

high quality products. But that's not all. There is a lot more to NSIC. The organization operates


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Hire purchase and Equipment Leasing Schemes for providing machinery and equipment at

doorsteps of the entrepreneurs. These schemes not only have been able to generate a class of

First Generation Entrepreneurs to set up enterprises with minimum investment, the schemes have

also acted as stimulants to the existing entrepreneur for expansion, diversification, modernization

and technology up gradation.

Though a chain of five NSIC Technical Service Centers are located at different parts of

the country, NSIC offers workshops, testing laboratories and common facilities to the

entrepreneurs and their workmen are provided with avenues for skill up gradation through

training in various technical trades. To encourage exports, NSIC has set up Software Technology

Parks providing complete infrastructure to enable small entrepreneurs to undertake Software

exports.

ACTIVITIES

Common facilities

Prototype development

Technology Transfer

Human Resource DevelopmentPlacements

Seminars and Workshops

ASSISSTING COUNTRIES WORLDWIDE

NSIC is committed to accelerate the growth of the small-scale sector not only in

India but also in similar countries worldwide NSICs efforts in assisting other countries with

infrastructure facilities and support service has been worthy.


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.

CHAPTER-1

GENERAL OVERVIEW


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GENERAL OVERVIEW

1.1 INTRODUCTION:

Technology is the word coined for the practical application of scientific knowledge in the industry.

The advancement in technology cannot be justified unless it is used for leveraging the users

purpose. Technology, is today, imbibed for accomplishment of several tasks of varied complexity,

in almost all walks of life.

The society as a whole is exquisitely dependent on science and technology.

Technology has played a very significant role in improving the quality of life. One way through

which this is done is by automating several tasks using complex logic to simplify the work.

1.2 AIM:

Vehicle access control system is an important sub-system of the intelligentized residence

section. Today, in a growing emphasis on personal and property safety, the control of vehicles'

access authorization and the management of the vehicles' access authority, access time and

access method via computer, is safe and convenient. This paper describes a set of vehicle access

control system based on ZigBee wireless technology. In this system, ZigBee coordinator and its

terminal nodes installed respectively in the entrance of the district and the vehicles, together

form a ZigBee wireless sensor network. This paper mainly introduces the overall structure,

hardware platform and software design of this system. The implementation and performance

tests of this system are fairly good.


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1.3 METHODOLOGY:

The above figure gives the pictorial representation of the procedure followed in the project

development.

In the specifications stage, the requirements of the model were identified. In order to

identify the requirements, literature survey was carried out.

The identified requirements and the specifications of the model were then analyzed to

identify whether or not they were viable. If any of the specifications seemed impracticable, the

specifications were reviewed.

Once the viable specifications were identified, the design of the product was developed.

A set of all possible test cases was also prepared simultaneously.

Specifications Analysis ProductDesign

TestCases

High-level

Desi n

Low-level

Desi n

Coding &Unit

Testing

IntegrationSystem

TestDocumentation

TestDesign

Successful

Failure


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The high level design document gives an overview of the design details.

The low level design document contains the intricate details of the product design.

The project was then divided into separate modules and each module was individually

soldered, coded and tested.

All the tested modules were then integrated. The integrated module was then tested for

the set of all possible test cases. In case the integrated module didnt work fora certain test case, the

specifications were reviewed accordingly.

In general, after every stage in project development, the specifications were reviewed.

After the integrated module satisfied all the test cases, different stages of the project were

documented.

1.4 SIGNIFICANCE OF PROJECT WORK:

During the course of our project we developed a multi system controller that is capable of

controlling devices that work on sensor supplies satisfactorily. We have developed a model that

gives a demo of industrial automation.


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CHAPTER-2

INTRODUCTION


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INTRODUCTION

2.1 INTRODUCTION TO EMBEDDED SYSTEMS:

2.1.1 EMBEDDED SYSTEMS:An embedded system is a specialized computer system that is housed in a large system in order to

carry out certain specific applications. Some embedded systems include operating systems and most

are so specialized such that the entire logic can be implemented as a single program.

2.1.2 APPLICATIONS OF EMBEDDED SYSTEMS:

Industrial machines Automobiles

Medical equipment

Cameras

Household appliances

Airplanes

Vending machines

Toys etc

2.2INTRODUCTION TO ZIGBEE

ZigBee coordinator(ZC): The most capable device, the coordinator forms the root of the

network tree and might bridge to other networks. There is exactly one ZigBee coordinator in

each network since it is the device that started the network originally. It is able to store

information about the network, including acting as the Trust Centre & repository for security

keys.

ZigBee Router (ZR): As well as running an application function a router can act as an

intermediate router, passing data from other devices.

ZigBee End Device (ZED): Contains just enough functionality to talk to the parent node (either

the coordinator or a router); it cannot relay data from other devices. This relationship allows the

node to be asleep a significant amount of the time thereby giving long battery life. A ZED


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requires the least amount of memory, and therefore can be less expensive to manufacture than a

ZR or ZC.

Protocols

The protocols build on recent algorithmic research (Ad-hoc On-demand Distance Vector,

neuRFon) to automatically construct a low-speed ad-hoc network of nodes. In most large

network instances, the network will be a cluster of clusters. It can also form a mesh or a single

cluster. The current profiles derived from the ZigBee protocols support beacon and non-beacon

enabled networks.

In non-beacon-enabled networks (those whose beacon order is 15), an unslotted CSMA/CA

channel access mechanism is used. In this type of network, ZigBee Routers typically have their

receivers continuously active, requiring a more robust power supply. However, this allows for

heterogeneous networks in which some devices receive continuously, while others only transmit

when an external stimulus is detected. The typical example of a heterogeneous network is a

wireless light switch: the ZigBee node at the lamp may receive constantly, since it is connected

to the mains supply, while a battery-powered light switch would remain asleep until the switch is

thrown. The switch then wakes up, sends a command to the lamp, receives an acknowledgment,

and returns to sleep. In such a network the lamp node will be at least a ZigBee Router, if not the

ZigBee Coordinator; the switch node is typically a ZigBee End Device.

In beacon-enabled networks, the special network nodes called ZigBee Routers transmit periodic

beacons to confirm their presence to other network nodes. Nodes may sleep between beacons,

thus lowering theirduty cycle and extending their battery life. Beacon intervals may range from

15.36 milliseconds to 15.36 ms * 214 = 251.65824 seconds at 250 kbit/s, from 24 milliseconds to

24 ms * 214 = 393.216 seconds at 40 kbit/s and from 48 milliseconds to 48 ms * 214 = 786.432

seconds at 20 kbit/s. However, low duty cycle operation with long beacon intervals requires

precise timing, which can conflict with the need for low product cost.
http://en.wikipedia.org/wiki/AODVhttp://en.wikipedia.org/wiki/NeuRFonhttp://en.wikipedia.org/wiki/CSMA/CAhttp://en.wikipedia.org/wiki/Wireless_light_switchhttp://en.wikipedia.org/wiki/Duty_cyclehttp://en.wikipedia.org/wiki/Kbit/shttp://en.wikipedia.org/wiki/Kbit/shttp://en.wikipedia.org/wiki/Duty_cyclehttp://en.wikipedia.org/wiki/Wireless_light_switchhttp://en.wikipedia.org/wiki/CSMA/CAhttp://en.wikipedia.org/wiki/NeuRFonhttp://en.wikipedia.org/wiki/AODV


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In general, the ZigBee protocols minimize the time the radio is on so as to reduce power use. In

beaconing networks, nodes only need to be active while a beacon is being transmitted. In non-

beacon-enabled networks, power consumption is decidedly asymmetrical: some devices are

always active, while others spend most of their time sleeping.

ZigBee devices are required to conform to the IEEE 802.15.4-2003 Low-Rate Wireless Personal

Area Network (WPAN) standard. The standard specifies the lowerprotocol layersthe physical

layer(PHY), and the medium access control (MAC) portion of the data link layer(DLL). This

standard specifies operation in the unlicensed 2.4 GHz, 915 MHz and 868 MHz ISM bands. In

the 2.4 GHz band there are 16 ZigBee channels, with each channel requiring 5 MHz of

bandwidth. The center frequency for each channel can be calculated as, FC = (2405 + 5 * (ch -

11)) MHz, where ch = 11, 12, ..., 26.

The radios use direct-sequence spread spectrum coding, which is managed by the digital stream

into the modulator. BPSK is used in the 868 and 915 MHz bands, and orthogonal QPSK that

transmits two bits per symbol is used in the 2.4 GHz band. The raw, over-the-air data rate is 250

kbit/sperchannel in the 2.4 GHz band, 40 kbit/s per channel in the 915 MHz band, and 20 kbit/s

in the 868 MHz band. Transmission range is between 10 and 75(up to 1500meteres for zigbee

pro.)meters (33 and 246 feet), although it is heavily dependent on the particular environment.

The maximum output power of the radios is generally 0 dBm (1 mW).

The basic channel access mode is "carrier sense, multiple access/collision avoidance"

(CSMA/CA). That is, the nodes talk in the same way that people converse; they briefly check to

see that no one is talking before they start. There are three notable exceptions to the use of

CSMA. Beacons are sent on a fixed timing schedule, and do not use CSMA. Message

acknowledgments also do not use CSMA. Finally, devices in Beacon Oriented networks that

have low latency real-time requirements may also use Guaranteed Time Slots (GTS), which by

definition do not use CSMA.
http://en.wikipedia.org/wiki/Protocol_(computing)http://en.wikipedia.org/wiki/Layerhttp://en.wikipedia.org/wiki/Physical_layerhttp://en.wikipedia.org/wiki/Media_Access_Controlhttp://en.wikipedia.org/wiki/Data_link_layerhttp://en.wikipedia.org/wiki/Hertzhttp://en.wikipedia.org/wiki/Megahertzhttp://en.wikipedia.org/wiki/ISM_bandhttp://en.wikipedia.org/wiki/Hertzhttp://en.wikipedia.org/wiki/Megahertzhttp://en.wikipedia.org/wiki/Megahertzhttp://en.wikipedia.org/wiki/Direct-sequence_spread_spectrumhttp://en.wikipedia.org/wiki/BPSKhttp://en.wikipedia.org/wiki/QPSKhttp://en.wikipedia.org/wiki/Kilobithttp://en.wikipedia.org/wiki/Secondhttp://en.wikipedia.org/wiki/Channel_(communications)http://en.wikipedia.org/wiki/Meterhttp://en.wikipedia.org/wiki/Foot_(length)http://en.wikipedia.org/wiki/DBmhttp://en.wikipedia.org/wiki/Carrier_Sense_Multiple_Accesshttp://en.wikipedia.org/wiki/Carrier_Sense_Multiple_Accesshttp://en.wikipedia.org/wiki/DBmhttp://en.wikipedia.org/wiki/Foot_(length)http://en.wikipedia.org/wiki/Meterhttp://en.wikipedia.org/wiki/Channel_(communications)http://en.wikipedia.org/wiki/Secondhttp://en.wikipedia.org/wiki/Kilobithttp://en.wikipedia.org/wiki/QPSKhttp://en.wikipedia.org/wiki/BPSKhttp://en.wikipedia.org/wiki/Direct-sequence_spread_spectrumhttp://en.wikipedia.org/wiki/Megahertzhttp://en.wikipedia.org/wiki/Megahertzhttp://en.wikipedia.org/wiki/Hertzhttp://en.wikipedia.org/wiki/ISM_bandhttp://en.wikipedia.org/wiki/Megahertzhttp://en.wikipedia.org/wiki/Hertzhttp://en.wikipedia.org/wiki/Data_link_layerhttp://en.wikipedia.org/wiki/Media_Access_Controlhttp://en.wikipedia.org/wiki/Physical_layerhttp://en.wikipedia.org/wiki/Layerhttp://en.wikipedia.org/wiki/Protocol_(computing)


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Software and Hardware

The software is designed to be easy to develop on small, inexpensive microprocessors. The radio

design used by ZigBee has been carefully optimized for low cost in large scale production. It has

few analog stages and uses digital circuits wherever possible.

Even though the radios themselves are inexpensive, the ZigBee Qualification Process involves a

full validation of the requirements of the physical layer. This amount of concern about the

Physical Layer has multiple benefits, since all radios derived from that semiconductor mask set

would enjoy the same RF characteristics. On the other hand, an uncertified physical layer that

malfunctions could cripple the battery lifespan of other devices on a ZigBee network. Where

other protocols can mask poor sensitivity or other esoteric problems in a fade compensation

response, ZigBee radios have very tight engineering constraints: they are both power and

bandwidth constrained. Thus, radios are tested to the ISO 17025 standard with guidance given by

Clause 6 of the 802.15.4-2006 Standard. Most vendors plan to integrate the radio and

microcontroller onto a single chip.

Controversy

An academic research group has examined the Zigbee address formation algorithm in the 2006

specification, and argues[6] that the network will isolate many units that could be connected. The

group proposed an alternative algorithm with similar complexity in time and space.

A white paperpublished by a European manufacturing group (associated with the development

of a competing standard, Z-Wave) claims that wireless technologies such as ZigBee, which

operate in the 2.4 GHz RF band, are subject to significant interference - enough to make them

unusable.[7] It claims that this is due to the presence of other wireless technologies like Wireless

LAN in the same RF band. The ZigBee Alliance released a white paper refuting these claims.[8]

After a technical analysis, this paper concludes that ZigBee devices continue to communicate

effectively and robustly even in the presence of large amounts of interference.
http://en.wikipedia.org/wiki/Analog_circuithttp://en.wikipedia.org/wiki/Digital_circuithttp://en.wikipedia.org/wiki/ISO_17025http://en.wikipedia.org/wiki/ZigBee#cite_note-5#cite_note-5http://en.wikipedia.org/wiki/White_paperhttp://en.wikipedia.org/wiki/Z-Wavehttp://en.wikipedia.org/wiki/ZigBee#cite_note-Zig_WLAN_Interference-6#cite_note-Zig_WLAN_Interference-6http://en.wikipedia.org/wiki/Wireless_LANhttp://en.wikipedia.org/wiki/Wireless_LANhttp://en.wikipedia.org/wiki/ZigBee#cite_note-Zig_WLAN_Interference_Refute-7#cite_note-Zig_WLAN_Interference_Refute-7http://en.wikipedia.org/wiki/ZigBee#cite_note-Zig_WLAN_Interference_Refute-7#cite_note-Zig_WLAN_Interference_Refute-7http://en.wikipedia.org/wiki/Wireless_LANhttp://en.wikipedia.org/wiki/Wireless_LANhttp://en.wikipedia.org/wiki/ZigBee#cite_note-Zig_WLAN_Interference-6#cite_note-Zig_WLAN_Interference-6http://en.wikipedia.org/wiki/Z-Wavehttp://en.wikipedia.org/wiki/White_paperhttp://en.wikipedia.org/wiki/ZigBee#cite_note-5#cite_note-5http://en.wikipedia.org/wiki/ISO_17025http://en.wikipedia.org/wiki/Digital_circuithttp://en.wikipedia.org/wiki/Analog_circuit


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.Advantages:

low cost allows the technology to be widely deployed in wireless control and monitoring

applications.

low power-usage allows longer life with smaller batteries,.

mesh networking provides high reliability and larger range.

Applications:

Home Automation

ZigBee Smart Energy

Telecommunication Applications

Personal Home

Hospital Care


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CHAPTER-3

MICROCONTROLLER


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MICROCONTROLLER

3.1 INTRODUCTION:

A microcontroller is a computer on a chip. It is an integrated chip that is usually a part of an

embedded system. It is a microprocessor that is meant to be more self contained, independent andyet function as a tiny, dedicated computer. It lays emphasis on high integration, low power

consumption, self sufficiency and cost effectiveness.

It is typically designed using the CMOS (complementary metal oxide semiconductor) technology

and has the following features:

a central processing unit

discrete input and output pins

serial input/output ports(UARTs)

peripherals such as timers, counters

RAM,ROM,EPROM,Flash Memory(EEPROM)

Clock generator

May include analog to digital converters

In-circuit programming and debugging support

Micro controller

Memory

(RAM/ROM)

I/O ports

Peripherals


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3.2 ADVANTAGES:

Design with microcontrollers has the following advantages:

It has low overall system cost as all the peripherals are integrated onto a single chip.

The product size is small, therefore the product is handy.

System design and troubleshooting is simple.

Since the peripherals are integrated on the same chip, the system is reliable.

Additional RAM and ROM can be easily interfaced as and when required.

Microcontrollers with on-chip ROM provides a software security feature.

3.3 ATMEL 89S52:

ATMEL 89C51 is a low power, high performance CMOS 8 bit microcomputer with 4K bytes of

flash programmable and erasable read only memory (PEROM).The device is manufactured using

Atmels high density, non volatile memory technology and is compatible with industry standard

MCS-51 instruction set. It provides highly flexible and cost effective solution to many embedded

control applications.

3.4 FEATURES OF ATMEL 89S52:

It has 4K bytes of in-system reprogrammable flash memory (1000 write/erase cycles).

Fully static operation: 0-24 MHz

Three level program memory lock

128 bytes internal RAM

32 programmable I/O lines(4 ports)

Two 16 bit timers/counters

Six interrupt sources

Programmable serial channel

Low power idle and Power down modes

8 bit CPU optimized for controlled applications

64 K of external program memory

Full duplex UART


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3.5 BLOCK DIAGRAM OF THE MICROCONTROLLER:

Fig 3.5 Block Diagram of the Microcontroller


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3.6 DESCRIPTION OF BLOCK DIAGRAM:

3.6.1 CENTRAL PROCESSING UNIT (CPU):The microcontroller consists of 8 bit ALU with associated registers like register A,

register B,Program status word(PSW),Stack pointer(SP) ,a 16 bit program counter(PC) and a 16 bit

data pointer register(DTPR).

3.6.2ARITHMETIC LOGIC UNIT(ALU):

The ALU performs arithmetic and logic functions on 8 bit variables. An important and unique

feature of the microcontroller architecture is that theALU can manipulate 1 bit as well as 8 bit data

types. It performs the Operations over the operands held by the temporary registers TMP1 and

TMP2.The temporary registers cannot be accessed by the user.

3.6.3 ACCUMULATOR (ACC):

It is referred to as register A or Acc.It is an 8 bit register. It holds the source

operand and stores the result of arithmetic operations. It is used as the source or destination register

for logical operations. It is either explicitly or implicitly specified in the instructions.

3.6.4 B REGISTER:

It is a special function register. It can be used to store one of the operands in multiply

and divide instructions. For all other instructions it is used as a scratch pad.

3.6.5 PROGRAM STATUS WORD (PSW):

It is one of the special function registers .It is an 8 bit register. It is a set of

Flags that indicate the status of the microcontroller.

CARRY BIT (CY):

This bit holds the carry bit in case of arithmetic operations. It also serves the purpose of

accumulator in case of Boolean operations. It is set to one when there is a carry out from the D7 bit.

It can also be rest or cleared through instructions.

CY AC FO RS1 RS0 OV -- P


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AUXILLARY CARRY (AC):

It is used in BCD operations usually. This bit is raised when a carry occurs from lower nibble to the

higher nibble during arithmetic operations on BCD numbers.

FLAG 0 (F0):Flag 0 is available to the user for general purpose.

REGISTER SELECT BITS (RS1 AND RS0):

The two bits RS1 and RS0 are used to select one of the four available register banks

As below:

OVERFLOW FLAG (OF):

The overflow flag was created specifically for the purpose of informing the programmer that the

result of the signed number operation is erroneous. If the result of an operation on signed numbers

is too big for a register, an overflow has occurred and the programmer must be notified.

PARITY (P):

The parity bit reflects the number of 1s in the accumulator.

P=0 implies that accumulator contains an even number of 1s.

P=1 implies that the accumulator contains odd number of 1s.

D1 bit is a user definable flag and is reserved for future use.

3.5.6 SPECIAL FUNCTION REGISTER BANK (SFR):

It is a set of special function registers that can be addressed using their respective addresses

allotted to them. The addresses lie in the range 80H-FFH.

RS1 RS0 REGISTER BANKS ADDRESS

0 0 0 00H-07H

0 1 1 08H-0FH

1 0 2 10H-17H

1 1 3 18H-1FH


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3.5.7 INPUT-OUTPUT (I/O) PORTS (P0-P3):

These four latches-drivers pairs have been allotted to the four parallel I/O ports. These latches have

been allotted addresses in the special function register bank. Using these allotted addresses, the user

can communicate with the ports.

3.5.8 BUFFER:

It is a special function register and consists of two registers namely transmit buffer and the

receive buffer. The transmit buffer receives data parallely and transmits serially. The receive buffer

on the other hand is serial in parallel out register.

3.5.9 TIMING AND CONTROL UNIT:

It derives the timing and control information required for the internal operation of the circuit

and the control information required for controlling the external bus.

3.5.10 OSCILLATOR:

It generates the basic timing clock signal required for the operation of the circuit using a

crystal oscillator connected externally.

3.5.11 EPROM AND PROGRAM ADDRESS REGISTER:

These blocks provide on chip EPROM and a mechanism to internally address the EPROM.

3.5.12 RAM AND RAM ADDRESS REGISTER:

They provide 128 bytes of RAM and a mechanism to internally address the RAM


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3.6 PIN DESCRIPTION OF AT89S52:

3.7 Pin Description

3.7.1VCC (PIN 40)

Supply voltage.

3.7.2 GND (PIN 20)

Ground.

3.7.3 Port 0 (PIN 32-39)

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 high-impedance inputs. Port

0 can also be configured to be the multiplexed low-order address/data bus during accesses to

external program and data memory. In this mode, P0 has internal pull-ups. Port 0 also receives the

code bytes during Flash programming and outputs the code bytes dur-ing program verification.

External pull-ups are required during program verification.

3.7.4 Port 1 (PIN 1-8)

Port 1 is an 8-bit bidirectional I/O port with internal pull-ups. 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 inter-

nal pull-ups and can be used as inputs. As inputs, Port 1 pins that are externally being pulled low


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will source current (IIL) because of the internal pull-ups. 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.

3.7.5 Port 2 (PIN 21-28)


sink/source four TTL inputs. When 1s are written to Port 2 pins, they are pulled high by the internal

pull-ups and can be used as inputs. As inputs, Port 2 pins that are externally being pulled low will

source current (IIL) because of the internal pull-ups. 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 program-ming 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) P1.7 SCK (used for In-System Programming)

3.7.6 Port 3 (PIN 10-17)


sink/source four TTL inputs. 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 3 receives some control signals for Flash

programming and verification. Port 3 also serves the functions of various special features of the

AT89S52, as shown in the following table.

3.7.7 RST (PIN 9)Reset input. A high on this pin for two machine cycles while the oscillator is running resets the

device. This pin drives high for 98 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.

3.7.8 ALE/PROG (PIN 30)


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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. 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 is weakly pulled high. Setting the ALE-disable bit has no

effect if the microcontroller is in external execution mode. Port Pin Alternate FunctionsP3.0 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 read strobe)

3.7.9 PSEN (PIN 29)

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 exter-nal data memory.

3.7.10 EA/VPP (PIN 31)

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.

3.7.11 XTAL1 (PIN 19)

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

3.7.12 XTAL2 (PIN 18)

Output from the inverting oscillator amplifier.


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CHAPTER-4

GAS SENSOR


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GAS SENSOR

INTRODUCTION:

A CO gas sensor according to the present invention includes a gas collecting container for

collecting a measured gas therein; a detecting section provided within the gas collecting

container and having at least a pair of electrodes positioned through electrolyte; and a voltage

applying apparatus for applying voltage to the detecting section. One of the electrodes of the

detecting section is a detection electrode having the capability of adsorbing at least one of

hydrogenous gas and CO gas when a voltage is applied and then oxidizing it. By introducing a

measured gas into a gas collecting container of the CO gas sensor and carrying out electrolysis

according to a potential sweep method or a pulse method with the measured gas being in contact

with the detecting section, a CO gas concentration in the measured gas can be measured based on

an electrical current value obtained at the detecting section and changes of the electrical current

with elapse of time. According to the CO gas sensor of the present invention, it is possible to

accurately carry out detection and measurement of the concentration of CO gas when CO gas is

to be detected or measured even in a gaseous atmosphere containing a relatively large amount of

hydrogen gas and CO2 gas.

DESCRIPTION:

FIELD OF THE INVENTION

The present invention relates to a CO gas sensor for measuring the concentration of CO gas

contained in a gaseous phase and to a method of measuring the concentration of CO gas, and in

particular relates to a CO gas sensor for measuring the concentration of CO gas in a gaseous

atmosphere containing relatively high concentrations of hydrogen gas and carbon dioxide gas, afuel cell power generating apparatus equipped with such CO gas sensor, and a method of

measuring the concentration of CO gas.


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BACKGROUND ART

In many cases, hydrogen gas is used as a fuel gas for fuel cells. As such hydrogen gas, a

hydrogen gas rich reforming gas which is obtained by reforming methanol or the like is used.

When manufacturing such a reforming gas, a tiny amount of carbon monoxide (CO), namely

several tens ppm to several hundred ppm, is present as impurities. For this reason, when such a

reforming gas is used as a fuel gas for a fuel cell, the CO gas is adsorbed on the surface of the

platinum catalyst of the fuel cell electrodes, thus hindering ionization of the hydrogen gas and

lowering the output of the fuel cell. In order to take appropriate measures to counter such a

problem caused by the CO gas, it is necessary to continuously monitor the concentration of CO

gas in the reforming gas used in the fuel cell.

Conventionally, as for the most commonly used CO gas sensor, there are known a controlled

potential analysis type CO gas sensor and a semiconductor type CO gas sensor. However, for the

reasons given below, neither of these CO gas sensors is appropriate for detecting CO gas in a

reforming gas.

Namely, the reforming gas contains hydrogen gas used as a fuel in the fuel cell for the amount of

about 75% thereof. In comparison with this, the reforming gas contains a relatively tiny amount

of CO gas as described above. Therefore, it becomes necessary to detect or measure CO gas in a

hydrogen gas atmosphere containing a relatively large amount of hydrogen gas. However, in the

case where the concentration of CO gas is measured in such a hydrogen gas rich atmosphere

using these CO gas sensors, there is a problem that it is difficult to accurately detect (qualitative

analysis) or measure (quantitative analysis) such CO gas with either type of CO gas sensor due to

influence of the hydrogen gas rich atmosphere in which interference by hydrogen gas occurs.

In view of the problem mentioned above, it is an object of the present invention to provide a CO

gas sensor which can accurately carry out detection (qualitative analysis) and measurement

(quantitative analysis) of the concentration of CO gas when CO gas is detected or measured in a

gaseous atmosphere containing a relatively large amount of hydrogen gas and carbon dioxide

gas, a fuel cell power generating apparatus equipped with such a CO gas sensor, and a method of

measuring the concentration of CO gas.


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CHAPTER-5

Relay


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diode inside the relay case. Alternatively a contact protection network, consisting of a capacitor

and resistor in series, may absorb the surge. If the coil is designed to be energized with AC, a

small copper ring can be crimped to the end of the solenoid. This "shading ring" creates a small

out-of-phase current, which increases the minimum pull on the armature during the AC cycle.[1]

By analogy with the functions of the original electromagnetic device, a solid-state relay is made

with a thyristor or other solid-state switching device. To achieve electrical isolation an

optocouplercan be used which is a light-emitting diode (LED) coupled with a photo transistor.

Types of relay

Latching relay

A latching relay has two relaxed states (bistable). These are also called 'keep' or 'stay' relays.

When the current is switched off, the relay remains in its last state. This is achieved with a

solenoid operating a ratchet and cam mechanism, or by having two opposing coils with an over-

center spring or permanent magnet to hold the armature and contacts in position while the coil is

relaxed, or with a remnant core. In the ratchet and cam example, the first pulse to the coil turns

the relay on and the second pulse turns it off. In the two coil example, a pulse to one coil turns

the relay on and a pulse to the opposite coil turns the relay off. This type of relay has the

advantage that it consumes power only for an instant, while it is being switched, and it retains its

last setting across a power outage. Reed relay

A reed relay has a set of contacts inside a vacuum orinert gas filled glass tube, which protects

the contacts against atmospheric corrosion. The contacts are closed by a magnetic field generated

when current passes through a coil around the glass tube. Reed relays are capable of faster

switching speeds than larger types of relays, but have low switch current and voltage ratings. See

also reed switch.

Mercury-wetted relay

A mercury-wetted reed relay is a form of reed relay in which the contacts are wetted with

mercury. Such relays are used to switch low-voltage signals (one volt or less) because of its low

contact resistance, or for high-speed counting and timing applications where the mercury

eliminates contact bounce. Mercury wetted relays are position-sensitive and must be mounted
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vertically to work properly. Because of the toxicity and expense of liquid mercury, these relays

are rarely specified for new equipment. See also mercury switch.

Polarized relay

A Polarized Relay placed the armature between the poles of a permanent magnet to increase

sensitivity. Polarized relays were used in middle 20th Century telephone exchanges to detect

faint pulses and correct telegraphic distortion. The poles were on screws, so a technician could

first adjust them for maximum sensitivity and then apply a bias spring to set the critical current

that would operate the relay.

Machine tool relay

A machine tool relay is a type standardized for industrial control of machine tools, transfer

machines, and other sequential control. They are characterized by a large number of contacts

(sometimes extendable in the field) which are easily converted from normally-open to normally-

closed status, easily replaceable coils, and a form factor that allows compactly installing many

relays in a control panel. Although such relays once were the backbone of automation in such

industries as automobile assembly, the programmable logic controller (PLC) mostly displaced

the machine tool relay from sequential control applications.

Contactor relay

A contactor is a very heavy-duty relay used for switching electric motors and lighting loads.

High-current contacts are made with alloys containing silver. The unavoidable arcing causes thecontacts to oxidize and silver oxide is still a good conductor. Such devices are often used for

motor starters. A motor starter is a contactor with overload protection devices attached. The

overload sensing devices are a form of heat operated relay where a coil heats a bi-metal strip, or

where a solder pot melts, releasing a spring to operate auxiliary contacts. These auxiliary

contacts are in series with the coil. If the overload senses excess current in the load, the coil is

de-energized. Contactor relays can be extremely loud to operate, making them unfit for use

where noise is a chief concern.

Solid-state relay

Solid state relay, which has no moving parts 25 amp or 40 amp solid state contactors

A solid state relay (SSR) is a solid state electronic component that provides a similar function to

an electromechanical relay but does not have any moving components, increasing long-term

reliability. With early SSR's, the tradeoff came from the fact that every transistor has a small
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voltage drop across it. This voltage drop limited the amount of current a given SSR could handle.

As transistors improved, higher current SSR's, able to handle 100 to 1,200 amps, have become

commercially available. Compared to electromagnetic relays, they may be falsely triggered by

transients.

Solid state contactor relay

A solid state contactor is a very heavy-duty solid state relay, including the necessary heat sink,

used for switching electric heaters, small electric motors and lighting loads; where frequent

on/off cycles are required. There are no moving parts to wear out and there is no contact bounce

due to vibration. They are activated by AC control signals or DC control signals from

Programmable logic controller (PLCs), PCs, Transistor-transistor logic (TTL) sources, or other

microprocessor controls.

Buchholz relay

A Buchholz relay is a safety device sensing the accumulation of gas in large oil-filled

transformers, which will alarm on slow accumulation of gas or shut down the transformer if gas

is produced rapidly in the transformer oil.

Forced-guided contacts relay

A forced-guided contacts relay has relay contacts that are mechanically linked together, so that

when the relay coil is energized or de-energized, all of the linked contacts move together. If one

set of contacts in the relay becomes immobilized, no other contact of the same relay will be ableto move. The function of forced-guided contacts is to enable the safety circuit to check the status

of the relay. Forced-guided contacts are also known as "positive-guided contacts", "captive

contacts", "locked contacts", or "safety relays".

Overload protection relay

One type ofelectric motoroverload protection relay is operated by a heating element in series

with the electric motor . The heat generated by the motor current operates a bi-metal strip or

melts solder, releasing a spring to operate contacts. Where the overload relay is exposed to the

same environment as the motor, a useful though crude compensation for motor ambient

temperature is provided.
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CHAPTER-6DESIGN AND IMPLEMENTATION

LIST OF COMPONENTS


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6.1 DESIGN AND IMPLEMENTATION

.Power supply circuit supplies +5V DC to all the passive components like resistors, capacitors,

IC and Microcontrollers.

BLOCK DIAGRAM

MICRO

CONTROLLER

PORER

SUPPLY


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(v) Capacitors in Series

Fig 6.7: Capacitors in series

When capacitors are connected in series (figure 5) their combined resistance is less than any of

the individual capacitances. There is a special equation for the combined capacitance of two

capacitors C1 and C2:

C = (C1C2)/(C1+C2)

6.3. RESISTORS

Fig 6.8: Resistors

Type : passive

Electronic symbol : (Europe)

(US)
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A resistor is a two-terminal electronic component that produces a voltage across its

terminals that is proportional to the electric current through it in accordance with Ohm's law:

V = IR

Resistors are elements of electrical networks and electronic circuits. The primary

characteristics of a resistor are the resistance, the tolerance, maximum working voltage and the

powerrating. Other characteristics include temperature coefficient, noise, and inductance.
http://en.wikipedia.org/wiki/Terminal_%28electronics%29http://en.wikipedia.org/wiki/Electronic_componenthttp://en.wikipedia.org/wiki/Voltagehttp://en.wikipedia.org/wiki/Proportionality_%28mathematics%29#Direct_proportionhttp://en.wikipedia.org/wiki/Electric_currenthttp://en.wikipedia.org/wiki/Ohm%27s_lawhttp://en.wikipedia.org/wiki/Electrical_networkshttp://en.wikipedia.org/wiki/Electrical_resistancehttp://en.wikipedia.org/wiki/Engineering_tolerance#Electrical_component_tolerancehttp://en.wikipedia.org/wiki/Electric_power#In_circuitshttp://en.wikipedia.org/wiki/Temperature_coefficienthttp://en.wikipedia.org/wiki/Electrical_noisehttp://en.wikipedia.org/wiki/Inductancehttp://en.wikipedia.org/wiki/Inductancehttp://en.wikipedia.org/wiki/Electrical_noisehttp://en.wikipedia.org/wiki/Temperature_coefficienthttp://en.wikipedia.org/wiki/Electric_power#In_circuitshttp://en.wikipedia.org/wiki/Engineering_tolerance#Electrical_component_tolerancehttp://en.wikipedia.org/wiki/Electrical_resistancehttp://en.wikipedia.org/wiki/Electrical_networkshttp://en.wikipedia.org/wiki/Ohm%27s_lawhttp://en.wikipedia.org/wiki/Electric_currenthttp://en.wikipedia.org/wiki/Proportionality_%28mathematics%29#Direct_proportionhttp://en.wikipedia.org/wiki/Voltagehttp://en.wikipedia.org/wiki/Electronic_componenthttp://en.wikipedia.org/wiki/Terminal_%28electronics%29


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CHAPTER-7

LCD


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LCD INTERFACING

Introduction

The most commonly used Character based LCDs are based on Hitachi's

HD44780 controller or other which are compatible with HD44580. In this

tutorial, we will discuss about character based LCDs, their interfacing

with various microcontrollers, various interfaces (8-bit/4-bit),

programming, special stuff and tricks you can do with these simple

looking LCDs which can give a new look to your application.

Pin Description

The most commonly used LCDs found in the market today are 1 Line, 2

Line or 4 Line LCDs which have only 1 controller and support at most of

80 characters, whereas LCDs supporting more than 80 characters make

use of 2 HD44780 controllers.

Most LCDs with 1 controller has 14 Pins and LCDs with 2 controller has

16 Pins (two pins are extra in both for back-light LED connections). Pindescription is shown in the table below.

Pin No. Name Description

Pin no. 1 VSS Power supply (GND)

Pin no. 2 VCC Power supply (+5V)

Pin no. 3 VEE Contrast adjust

Pin no. 4 RS

0 = Instruction input

1 = Data input

Pin no. 5 R/W0 = Write to LCD module

1 = Read from LCD module

Pin no. 6 EN Enable signal

Pin no. 7 D0 Data bus line 0 (LSB)

Pin no. 8 D1 Data bus line 1


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Pin no. 14 D7 Data bus line 7 (MSB)

DDRAM - Display Data RAM

Display data RAM (DDRAM) stores display data represented in 8-bit

character codes. Its extended capacity is 80 X 8 bits, or 80 characters.

The area in display data RAM (DDRAM) that is not used for display can

be used as general data RAM. So whatever you send on the DDRAM is

actually displayed on the LCD. For LCDs like 1x16, only 16 characters

are visible, so whatever you write after 16 chars is written in DDRAM but

is not visible to the user.

CGROM - Character Generator ROM

Now you might be thinking that when you send an ASCII value to

DDRAM, how the character is displayed on LCD? So the answer is

CGROM. The character generator ROM generates 5 x 8 dot or 5 x 10 dot

character patterns from 8-bit character codes (see Figure 5 and Figure 6

for more details). It can generate 208 5 x 8 dot character patterns and 32

5 x 10 dot character patterns. User defined character patterns are also

available by mask-programmed ROM.

As you can see in both the code maps, the character code from 0x00 to

0x07 is occupied by the CGRAM characters or the user defined

characters. If user wants to display the fourth custom character then the

code to display it is 0x03 i.e. when user sends 0x03 code to the LCD
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DDRAM then the fourth user created character or pattern will be

displayed on the LCD.

CGRAM - Character Generator RAM

As clear from the name, CGRAM area is used to create customcharacters in LCD. In the character generator RAM, the user can rewrite

character patterns by program. For 5 x 8 dots, eight character patterns

can be written, and for 5 x 10 dots, four character patterns can be

written.

BF - Busy Flag

Busy Flag is a status indicator flag for LCD. When we send a command

or data to the LCD for processing, this flag is set (i.e. BF =1) and as soon

as the instruction is executed successfully this flag is cleared (BF = 0).

This is helpful in producing and exact amount of delay for the LCD

processing.

To read Busy Flag, the condition RS = 0 and R/W = 1 must be met and

The MSB of the LCD data bus (D7) act as busy flag. When BF = 1 means

LCD is busy and will not accept next command or data and BF = 0

means LCD is ready for the next command or data to process.

Instruction Register (IR) and Data Register (DR)

There are two 8-bit registers in HD44780 controller Instruction and Data

register. Instruction register corresponds to the register where you sendcommands to LCD e.g. LCD shift command, LCD clear, LCD address etc.

and Data register is used for storing data which is to be displayed on

LCD. When send the enable signal of the LCD is asserted, the data on

the pins is latched in to the data register and data is then moved
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automatically to the DDRAM and hence is displayed on the LCD.

Data Register is not only used for sending data to DDRAM but also for

CGRAM, the address where you want to send the data, is decided by the

instruction you send to LCD.

4-bit programming of LCD

In 4-bit mode the data is sent in nibbles, first we send the higher nibble

and then the lower nibble. To enable the 4-bit mode of LCD, we need to

follow special sequence of initialization that tells the LCD controller that

user has selected 4-bit mode of operation. We call this special sequence

as resetting the LCD. Following is the reset sequence of LCD.

Wait for about 20mS

Send the first init value (0x30)

Wait for about 10mS

Send second init value (0x30)

Wait for about 1mS

Send third init value (0x30)

Wait for 1mS

Select bus width (0x30 - for 8-bit and 0x20 for 4-bit)

Wait for 1mS

The busy flag will only be valid after the above reset sequence. Usually

we do not use busy flag in 4-bit mode as we have to write code for

reading two nibbles from the LCD. Instead we simply put a certain

amount of delay usually 300 to 600uS. This delay might vary depending

on the LCD you are using, as you might have a different crystal


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frequency on which LCD controller is running. So it actually depends on

the LCD module you are using.

In 4-bit mode, we only need 6 pins to interface an LCD. D4-D7 are thedata pins connection and Enable and Register select are for LCD control

pins. We are not using Read/Write (RW) Pin of the LCD, as we are only

writing on the LCD so we have made it grounded permanently. If you

want to use it, then you may connect it on your controller but that will

only increase another pin and does not make any big difference.

Potentiometer RV1 is used to control the LCD contrast. The unwanted

data pins of LCD i.e. D0-D3 are connected to ground.

Sending data/command in 4-bit Mode

We will now look into the common steps to send data/command to LCD

when working in 4-bit mode. In 4-bit mode data is sent nibble by nibble,

first we send higher nibble and then lower nibble. This means in both

command and data sending function we need to separate the higher 4-

bits and lower 4-bits.

The common steps are:

Mask lower 4-bits

Send to the LCD port

Send enable signal

Mask higher 4-bits

Send to LCD port

Send enable signal
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CHAPTER-8POWER SUPPLY


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POWER SUPPLY

8.1 1N4007:

8.1.1 FEATURES:

Low forward voltage drop

High surge current capability

8.1.2 ABSOLUTE MAXIMUM RATINGS:

Symbol Parameter Value Unit

IO verage Rectified Current 0.375 lead length

@ TA=750C

1.0

If(surge) Peak forward surge current

8.3ms single half-sine-waveSuperimposed on rated load

30

PD Total Device Dissipation

Derate above 250C

2.5

20

W

mW/C

RJA Thermal Resistance, Junction to Ambient 50 C/W

Tstg Storage Temperature Range -55 to +175 C

TJ Operating Junction Temperature -55 to +150 C


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8.2 3-TERMINAL 500mA VOLTAGE REGULATOR:(KA7805, KA7812)

8.2.1 FEATURES:

Output current of 500mA

Output Voltages of 5V,12V

Thermal overload protection

Short circuit protection

Output transistor Safe Operating Area Protection

8.2.2 DESCRIPTION:


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The 3-Terminal Regulator is available in 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 shutdown and safe operating area protection, making it essentially indestructible.

If adequate heat sinking is provided, they can deliver 1A output current. Although it is designed as

a fixed voltage regulator primarily, the device can be used with external components to obtain

adjustable voltages and currents.

8.2.3. INTERNAL BLOCK DIAGRAM:

SERIESPASS

ELEMENT

Current

Generator

SOA

protection

Startingcircuit

Referencevoltage

Error

Amplifier

Thermal

protection

Input Output

Gnd


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0=8V to 18V

Dropout voltage VDrop 0=1A,TJ=+25C

Short Circuit Current ISC I=35V,TA=25C 30 M A

Peak current PK J=25C 2

8.2.6 ELECTRICAL CHARACTERISTICS OF 7812 REGULATOR:

Parameter Symbol Conditions Min. Typ. Max Unit

Output voltage V0 J=+25C 11.5 2.0 .5

5mAI01A,

015W,V1=7V to 20V

11.4 2.0 .6

Line Regulation Regline TJ=25C O=14.5V

30V

10.0 40

MV

I=16V

V

.0 120

Load Regulation Regload TJ=25C I0=5mA

1. 5mA

11 240

MV

0=250mA

750mA

0 120

Quiescent Current 0 TJ=+25C .1 .0 mA

Quiescent Current Change IQ I0=5mA to 1A 1 5 mA

I=14.5V to 30V . 5 0

Output voltage drift V0/T I0=5mA mV/C

Output noise voltage VN F=10Hz to 10kHz 6 V/V0

Ripple Rejection RR F=120Hz

V0=15V to 25V

5 71 DB

Dropout voltage VDrop I0=1A,TJ=+25C

Short Circuit Current ISC VI=35V,TA=25C 30 mA

Peak current IPK J=25C 2.2


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8.2.7 TYPICAL PERFORMANCE CHARACTERISTICS:

fig. peak output current

Fig: output voltage


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8.3 B

C 547 TRANSISTOR:

8.3.1 GENERAL DIAGRAM:

Collector

1

Base

2

3

Emitter


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8.3.2 MAXIMUM RATINGS:

Rating Symbol BC547 Unit

Collector-Emitter voltage VCE0 45 Vdc

Collector-Base voltage VCB0 50 Vdc

Emitter-Base voltage VEB0 6.0 Vdc

Collector current continuous Ic 100 MAdc

Total device Dissipation @TA=25C

Derate above 25C

PD 625

50

mW

mW/C

8.3.3 THERMAL CHARACTERISTICS:

Characteristics Symbol Max. Unit

Thermal resistance, junction to ambient R_JA 00 C/W

Thermal resistance, junction to case R_JC 3.3 C/W

8.3.4 ELECTRICAL CHARACTERISTICS:

1. OFF CHARACTERISTICS:

Characteristic Symbol Min. Typ. Max. Unit

Collector-emitter breakdown voltage

IC=1.0mA,IB=0)

V(BR)CE0 45

Collector-base breakdown voltage

dc)

V(BR)CB0 50

Emitter-base breakdown voltage

IE=10A,IC=0)

V(BR)EB0 6.0

Collector cutoff current

(VCE=50V,VBE=0)

(VCE=30V,TA=125C)

ICES 0.2

-

15

4.0

nA

A


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2. ON CHARACTERISTICS:

Characteristic Symbol Min. Typ. Max. Unitcurrent gain

IC=2.0mA,VCE=5.0V)

hFE 10 800

Collector-emitter saturation voltage

IC=10mA,IB=0.5mA)

IC=100mA,IB=5.0mA)

IC=10mA)

VCE(sat)

0.09

0.2

0.3

0.25

0.6

0.6

Base-emitter On voltage

IC=2.0mA,VCE=5.0V)

IC=10mA,VCE=5.0V)

IBE(on)

0.55 0.7

0.77

Base-emitter saturation voltage VBE(sat) 0.7

3. SMALL CHARACTERISTICS:

Characteristic Symbol Min. Typ. Max. Unit

Current gain Band Width Product

IC=10mA,VCE=5.0,f=100Mhz)

fT 150 300 MHz

Output capacitance

(VEB=0.5V,IC=0,f=1.0Mhz)

Cobo - 1. 7 4.5 pF

Input capacitance

(VEB=0.5V,IC=0,f=1.0Mhz)

Cibo 10 pF

Small signal current gain

IC=2.0mA,VCE=5.0V,f=1.0khz)

Hfe 125 900

Noise Figure

(IC=0.2mA,VCE=5.0V,Rs=2K,

F =1.0khz,f=200hz)

NF 2 .0 10 dB


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8.4 POWER SUPPLY

8.4.1 OPERATION:

. The input voltage to the diodes 1 and 2 is supplied from a transformer and is equal to the peak

AC voltage of the secondary winding of the transformer as shown in graph 1.

. The circuit consisting of the combination of the two diodes is called full wave rectifier and the

output of this is graph 2 which contains high ripple.

. These diodes combined with a capacitor are known as full wave rectifier with a capacitor.

. This capacitor is known as filtering capacitor improves the output of the rectifier considerably and

the output of this stage is shown in graph 3.

. The efficiency of this rectifier is 81.2%.

. The resistor is used to limit the voltage and current those are supplied to the regulator in order to

avoid the regulator from getting damaged.

. The diode 3 is used to protect the diodes 1 and 2 from the back current discharged by the

capacitor.

VIN (ac)

VIN (ac)

Vout (dc)1 2 3

Regulator|

|

|

||

||

2|

|

|

||

||

3|

|

|

||

||

4


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. The output at this point is not completely regulated since there is still some amount of ripple

present in the rectified voltage.

. Therefore a regulator is used to ensure low voltage ripple and excellent load and line voltage

regulation.

. The graph 4 gives the output of the regulator and this voltage is 99.9% regulated.

. The resistor after the regulator is used to limit the current supplied to the LED.

.When the voltage supplied is greater than 3.8V, the LED will glow.

. The regulated DC voltage output is taken across the capacitor and is further supplied to other

applications.

8.4.2 OUTPUT AT DIFFERENT STAGES OF THE POWER SUPPLY:

Voltage

T

T

T

T

1

2

3

4


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CHAPTER-9

KEIL VISION3

SOFTWARE


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9. KEIL VISION3 SOFTWARE

9.1 VISION3 OVERVIEW:

The Vision3 IDE is a windows based software development platform that combines a

robust editor, project manager, and integrated make facility. Vision3 integrates all tools

including the C compiler, macro assembler, linker/locator, and HEX file generator. Vision3

helps expedite the development process of our embedded applications by providing the

following:

Full-featured source code editor

Device database for configuring the development tool setting

Project manager for creating and maintaining our projects

Integrated make facility for assembling, compiling, and linking our embedded

applications

Dialogs for all development tool settings

True integrated source level Debugger with high-speed CPU and peripheral simulator

Advanced GDI interface for software debugging in the target hardware and for

connection to Keil ULINK

Flash programming utility for downloading the application program into Flash ROM

Links to development tools manuals, device datasheets and users guides

.In the Build Mode, we maintain the project files and generate the

application. In the Debug Mode, we verify our program either with a powerful CPU and

peripheral simulator or with the Keil ULINK USB-JTAG Adapter (or other AGDI drivers) that

connect the debugger to the target system. The ULINK allows us also to download our

application into Flash ROM of our target system.


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9.2 FEATURES and BENEFITS:

Feature BenefitThe Vision3 Simulator is the only

Debugger that completely simulates all

on-chip peripherals.

Write and test the application code before production

hardware is available. Investigate different hardware

configurations to optimize the hardware design.

Simulation capabilities may be expanded

using the Advanced Simulation Interface

(AGSI).

Sophisticated systems can be accurately simulated

by adding our own peripheral drivers.

The Code Coverage feature of the

Vision3 Simulator provides analysis of

our programs execution.

Safety-critical systems can be thoroughly tested and

validated. Execution analysis reports can be viewed

and printed for certification requirements.

The Vision3 Device Database

automatically configures the

development tools for the target micro

controller.

Mistakes in tool settings are practically eliminated

and tool configuration time is minimized.

The Vision3 IDE integrates additional

third-party tools like VCS, CASE, and

FLASH/Device Programming.

Quickly access development tools and third-party

tools. All configuration details are saved in the

Vision3 project.

Identical Target Debugger and Simulator

User Interface.

Shortens our learning curve.

Vision3 incorporates project manager,

editor, and debugger in a single

environment.

Accelerates application development. While editing,

we may configure debugger features. While

debugging, we may make source code modifications.


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The tabs of the Project Workspace give us access to:

Files and Groups of the project.

CPU Registers during debugging.

Tool and project specific on-line Books.

Text Templates for often used text blocks.

Function in the project for quick editor navigation.

The tabs of the Output Window provides: Build messages and fast error access;

Debug Command input/output console; Find in Files results with quick file access.

The Memory Window gives access to the memory areas in display various formats.

The Watch and Call Stack Window allows us to review and modify program variables and

displays the current function call tree.

The Workspace is used for the file editing, disassembly output, and other debug

information.

The Peripheral Dialogs help us to review the status of the on-chip peripherals in the

microcontroller.

9.4 SOFTWARE DEVELOPMENT LIFE CYCLE:

When you use the Keil Vision3, the project development cycle is

roughly the same as it is for any other software development project.

1. Create a project, select the target chip from the device database, and configure the tool

settings.

2. Create source files in C or assembly.

3. Build our application with the project manager.

4. Correct errors in source files.

5. Test the linked application.


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files and organize them into a project that defines our target application. Vision3 automatically

compiles, assembles, and links our embedded application and provides a single focal point for

our development efforts.

9.4.2 C COMPILER & MACRO ASSEMBLER:

Source files are created by the Vision3 IDE and are passed to the C or EC++ Compiler

or Macro Assembler. The compiler and assembler process source files and create re-locatable

object files.

9.4.3 LIBRARY MANAGER:

The library manager allows us to create object library from the object files created by the

compiler and assembler. Libraries are specially formatted, ordered program collections of object

modules that may be used by the linker at a later time. When the linker processes a library, only

those object modules in the library that are necessary to create the program are used.

9.4.4 LINKER/LOCATOR:

The Linker/Locator creates an executable program file using the object modules extracted

from libraries and those created by the compiler and assembler. An executable program file (also

called absolute object module) contains no re-locatable code or data. All code and data reside at

fixed memory locations. This executable program file may be used:

To program an Flash ROM or other memory devices,

With the Vision3 Debugger for simulation and target debugging,

With an in-circuit emulator for the program testing.

9.4.5 VISION3 DEBUGGER:

The Vision3 symbolic, source-level debugger is ideally suited for fast, reliable program

debugging. The debugger includes a high-speed simulator that let us simulate a microcontroller


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system including on-chip peripherals and external hardware. The attributes of the chip you use

are automatically configured when we select the device from the Device Database.

The Vision3 Debugger provides several ways for us to test our programs on real target

hardware. Use the Keil ULINK USB-JTAG adapter for Flash downloading and software

test of our program via on-chip debugging system like the Embedded ICE macro cell that

is integrated in many ARM devices.

Use the AGDI interface to attach use the Vision3 Debugger front end with our target

system using other debuggers like Monitor, In-System Debugger, or Emulator.

9.5 USER INTERFACE:

The Vision3 User Interface consists of menus, toolbar buttons, keyboard shortcuts,

dialog boxes, and windows that you use as you interact with and manage the various aspects of

your embedded project.

The menu bar provides menus for editor operations, project maintenance, development

tool option settings, program debugging, external tool control, window selection and

manipulation, and on-line help.

The toolbar buttons allow you to rapidly execute Vision3 commands. A Status Bar

provides editor and debugger information. The various toolbars and the status bar can be

enabled or disabled from the View Menu commands.

Keyboard shortcuts offer quick access to Vision3 commands and may be configured via

the menu command Edit-Configuration-Shortcut key.

The following sections list the Vision3 commands that can be reached by menu

commands, toolbar buttons, and keyboard shortcuts. The Vision3 commands are grouped

mainly based on the appearance in the menu bar:

File Menu and File Commands

Edit Menu and Edit Commands

View Menu


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Project Menu and Project Commands

Debug Menu and Debug Commands

Peripherals Menu

9.5.1. FILE MENU AND COMMANDS:

File Menu Tool bar Short cut Description

New... Ctrl+N Create a new source or text file

Open Ctrl+O Open an existing file

Close Close the active file

Save Ctrl+S Save the active file

Save as... Save and rename the active file

Save All Save all open source and text files including project

and the active file

Device Database Maintain the Vision3 device database

License

Management

Maintain and review the installed software

components

Print Setup... Setup the printer

Print Ctrl+P Print the active file

Print Preview Display pages in print view

1 .. 10 Open the most recent used source or text files

Exit Quit Vision3 and prompt for saving files


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9.5.2 PERIPHERALS MENU:

Menu Item

Reset CPU

Sets CPU to reset state.

Interrupts

Opens dialog for the interrupt controller.

I/O Ports

Opens dialogs for the on-chip I/O Ports.

Serial

Opens dialogs for the on-chip Serial Port.

Timer

Opens dialogs for the on-chip Timers/Counters.

Watchdog

Opens dialogs for the on-chip Watchdog Timer.

A/D Converter

Opens dialogs for the on-chip Analog to Digital Converter.

D/A Converter

Opens dialogs for the on-chip Digital to Analog Converter.

IC Controller

Opens dialogs for the on-chip IC Controller.

CAN Controller

Opens dialogs for the on-chip CAN Controller.


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9.6 CREATING APPLICATIONS:

Create a Project: explains the steps required to setup a simple application and to

generate HEX output.

Project Target and File Groups: shows how to create application variants and

organized the files that belong to a project.

Tips and Tricks: provides information about the advanced features of the

Vision3 Project Manager.

9.6.1 CREATE A PROJECT:

Vision3 includes a project manager which makes it easy to design applications for an

ARM based microcontroller. We need to perform the following steps to create a new project:

Create Project file and Select CPU

Project Workspace-Books

Create New Source Files

Add Source Files to the Project

Create Files Groups

Set tool Options for Target Hardware

Configure the CPU Start-up Code

Build Project and Generate Application Program Code

Create a HEX File for PROM Programming

9.6.2 Description:

Create Project file and Select CPU:

To create a new project file, go to the Vision3 menu and select Project New

Vision Project. The Create New Project dialog asks us for the new project file name. At this


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time navigate to the folder where our new project will reside. It's a good idea to use a separate

folder for each project. Use the icon Create New Folder in this dialog to create a new empty

folder. Select this folder and enter the file name for the new project, i.e. Project1. Vision3

creates a new project file with the name PROJECT1.UV2which contains a default target and file

group name. We can see these names in the Project WorkspaceFiles.

Select Microcontroller from Device Database:

When we create a new project Vision3 asks us to select a CPU for our project. The

Select Device dialog box shows the Vision3 device database. Just select the microcontroller

you use. For the example in this chapter we are using the Philips LPC2106 controller. This

selection sets necessary tool options for the LPC2106 device and simplifies the tool

configuration.

Copy and Add the CPU Start-up Code:

An embedded program requires CPU initialization code that needs to match the

configuration of our hardware design. This Start-up Code depends also on the tool chain that we

are using. Since we might need to modify that file to match our target hardware, the file should

be copied to our project folder.
http://www.keil.com/support/man/docs/uv3/uv3_ca_projtargfilegr.htm


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Configure Start-up Code:

The CPU Start-up Code (on most ARM targets the file name is Startup.S) may be open

from the Project WorkspaceFiles Tab. Most start-up files have embedded comments for the

Vision3 Configure Wizard which provides menu driven selections.


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The default settings of the Start-up Code give a good starting point on most single chip

applications. However you need to adapt the configuration for your target hardware. CPU/PLL

clock and BUS system is target specific and cannot be automatically configured. Some devices

provide options to enable or disable on-chip components (for example on-chip xdata RAM on

8051 variants).We must ensure that the settings in the start-up file match the other settings in

your project. The button Edit as Text opens the Start-up Code in a standard editor window and

allows us to review the source code of this file.

Build a Project:

Typically, the tool settings under Options Target are all we need to start a new application.

We may translate all source files and link the application by clicking on the Build Target toolbar

button.


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We may start our PROM programming utility after the make process when us specify the

program under the option UserRun User Program #1 as explained under Start ExternalTools

9.7 PROJECT TARGETS AND FILE GROUPS:

By using different Project Targets Vision3 lets us create several programs from a

single project. We may need one target for testing and another target for a release version of your

application. Each target allows individual tool settings within the same project file. Files Groups

let us group associated files together in a project. This is useful for grouping files into functional

blocks or for identifying engineers in our software team. We have already used file groups in our

example to separate the CPU related files from other source files. With these techniques it is

easily possible to maintain complex projects with several 100 files in Vision3.

The dialog Project-Components, Environment, Books-Project Components allows us

to create project targets and file groups. We have already used this dialog to add system

configuration files in a file group. An example project structure is shown below.


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The Project Workspaceshows all groups and the related files. Files are built and linked in the

same order as shown in this window. You can move file positions with Drag & Drop . We may

select a target or group name and Clickto rename it. The local menu opens with a right mouse

Click and allows you for each item:

to set tool options

to remove the item

to add files to a group

to open the file.

In the build toolbar you can quickly change the current project target to build.

9.7.1 TIPS AND TRICKS:

The following section discusses advanced techniques we may use with the Vision3 Project

Manager.


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Start External Tools after Build Process shows how to execute programs after a

successful build command which is useful for post-processing as required for symbol

information by some emulators or programmers.

Specify a Separate Folder for Listing and Object Files lets us direct the object and

listing files of your project to specific folders.

Use a CPU that is not in the Vision Device Database explains how to define new

Devices that can be selected from the Device Database.

Create a Library File gives us the tool setup that is required for creating library files.

File Extensions allows us to set the file extension for the various file types of a project.

Import Project Files from Vision Version 1 explains you how to import existing

Vision Version 1 *.PRJ files.

Version and Serial Number Information allows you to view project specific tool

version information.

File and Group Specific Options are set via Options for ... in context menu that opens via a

right mouse click on an item in the Project Workspace.

Options for ... provides the following configuration options:

Properties Dialog allows us to set file and group specific options.

Include Always specific Library Modules specify library modules that should be always

included in a project.


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CHAPTER-10

CODE


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CHAPTER-11

TESTING


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TESTING THE CIRCUIT

11.1BASIC TESTS:

It is essential to conduct certain preliminary tests prior to testing the software to prevent the damageof the electronic components.

11.2CHECKING THE POWER SUPPLY:

The power supply circuit is expected to produce a constant dc power supply of 5V (or 12V).The

magnitude of the dc voltage given by the circuit depends upon the voltage regulator used.

To test the circuit, a 9-0-9 step down transformer (12-0-12V) is used. The primary is connected

to 230V AC and the secondary is connected to the full wave rectifier part of the circuit. Upon

switching on of the mains, the LED must glow and the voltage across the output terminals must

show 5V (or 12V).

11.3CHECKING THE ICs:

The pins of various ICs used are to be checked properly for their default status in order to ensure

smooth functioning.

The power supply is connected to the chips and voltages across corresponding pins are

checked using a digital multimeter.By default, the input ports of the microcontroller are configured

to 1 and the output ports are configured to 0.

When the microcontrollers havent been connected, the address and data pins of the

encoder and decoders default to 0.


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CONCLUSION

A multi system controller allows several electronic gadgets to be controlled by a

single device. This enables automation in any environment that has several electronic devices.

During the course of our project, we have developed a working model to demonstrate the

functioning of a multi system controller using RF communication. The device developed is simple

and controls three devices i.e. bulbs, fan and a remote controlled car. This device is capable of

controlling devices that run on both ac and/or dc power supply.

12.1 FUTURE SCOPE:

With increased complexity, this device can be successfully used in any environment where

automation is desired.


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APPENDIX


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APPENDIX

BIBLIOGRAPHY

REFERENCE BOOKS:

8051 MICROCONTROLLERS AND EMBEDDED SYSTEMS- MAZIDI & MAZIDI

ADVANCED MICROPROCESSORS AND PERIPHERALS- RAY AND BHURCHANDI

REFERENCE SITES:

www.keil.com

www.wisegeek/microcontroller.com

www.wikipedia.com

www.mytutorialcafe.com

www.avrfreaks.com

www.softpedia.com

www.rfsolutions.co.uk

www.freewebs.com

www.tpub.co

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