smart energy meter project report

5/25/2018 Smart Energy Meter Project Report

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KEYWORDS

ACC : Accumulator

B : B Register

PSW : Program Status Word

SP : Stack Pointer

DPTR : Data Pointer

DPL : Low byte

DPH : High byte

P0 : Port 0

P1 : Port 1

P2 : Port 2

P3 : Port 3

IE : Interrupt Enable control

IP : Interrupt Priority control

TMOD : Timer/counter Mode control

TCON : Timer/counter control

T2CON : Timer/counter 2 control

T2MOD : Timer/counter mode2 control

TH0 : Timer/counter 0high byte

TL0 : Timer /counter 0low byte

TH1 : Timer/counter 1high byte

TL1 : Timer/counter 1low byte

TH2 : Timer/counter 2 high byte

TL2 : Timer/counter 2 low byte

SCON : Serial control

SBUF : Serial data buffer

PCON : Power control

IR : Infra Red


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INDEX

ACKNOWLEDGE ------------------------------------ 6ABSTRACT ------------------------------------ 7

I.INTRODUCTION 9

II. LITERATURE SURVEY2.1 Motivation 11

2.2 Background 11

2.3 Aim 11

2.4 Requirement Analysis 12

2.4.1 Hardware Requirements 12

2.4.2 Software Requirements 12

2.5 Scope 12

2.6 Advantages 12

III.DESIGN METHODOLOGY3.1 Hardware system design 14

3.1.1 Block level design of Smart Energy Meter 14

3.1.2 Selection of Hardware 15

3.1.3 Design consideration of Microcontroller 15

3.1.3.1 8051 15

3.1.3.2 Internal architecture of P89C51RD2FN 16

3.1.3.2.1 I/O ports 173.1.3.2.2 Interrupt controls 18

3.1.3.2.3 Bus controllers 19

3.1.3.2.4 Memory organization 19

3.1.3.2.5 Registers in 8051 20

3.1.3.2.6 Oscillator 22

3.1.3.3 Features 23

3.1.4 Serial communication 24

3.1.4.1 Introduction 24

3.1.4.2 Baud rate 25

3.1.5 Hardware design of LCD 25

3.1.5.1 LCD screen 263.1.5.2 Features 29

3.1.5.3 Pin configuration 29

3.1.5.4 Specifications 30

3.1.5.5 Functionality of LCD in project 32

3.1.6 MAX232 32


3.1.7 RS232 (Female port) 33

3.1.7.1 Voltage levels 33


3.1.7.3 DB9 interfacing microcontroller using MAX232 34

3.1.8 Serial port connector 353.1.9 Design of KEYPAD 35


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3.1.10 IR sensors and IC NE555 Timer 37

3.1.10.1 Photo transmitter 37

3.1.10.2 Principle of operation 38

3.1.10.3 Application 39

3.1.10.4 Features 39

3.1.10.5 IR receivers 393.1.10.6 Photo transistor 39

3.1.10.7 Principle of operation 39

3.1.11 IC NE555 timer 40

3.1.12 Resistors 41

3.1.13 Capacitors 41

3.1.14 Crystal oscillators 42

3.2 Software design 43

3.2.1 Liquid Crystal Display 43

3.2.1.1 Initialization of LCD 43

3.2.1.2 Checking busy state of LCD 43

3.2.2 KEYPAD 473.2.2.1 Flow chart of keyboard scanning algorithm 47

IV. IMPLEMENTATION4.1 Hardware implementation 49

4.1.1 Complete Schematic of Smart Energy Meter 50

4.1.2 Connections of P89C51RD2FN 51

4.1.3 Pin connections of LCD 52

4.1.4 Keypad connections 53

4.1.5 MAX232 and DB9 connections 53

4.1.6 IC555 timer and IR transmitter connections 54

V. SOFTWARE IMPLEMENTATION5.1 JHD162A LCD interfacing 56

5.1.1 Initialization of LCD 56

5.1.2 Initialization sequence code 56

5.1.3 Checking the busy state of LCD 56

5.1.4 Writing the command to display 57

5.1.5 Writing data to display 57

5.1.6 Displaying the data into LCD 57

5.1.7 4*4 matrix Keypad interfacing 58

5.1.8 Sensors 58

VI. DEBUGGING TECHNIQUES6.1 KEIL micro vision debugger 61

6.1.1 Introduction to KEIL IDE 61

6.1.2 Features 61

6.1.3 Steps to follow while writing program in KEIL 62

6.2 Flash Magic 63

6.2.1 Features 63

6.3 Null MODEM checking (HYPER TERMINAL) 64

6.4 Hardware debugging techniques 65CONCLUSION 65


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RESULT 66

VII. BIBILOGRAPHY 67VIII. APPENDIX

KEIL MICROVISION IDE 68

FLASH MAGIC 77

SET UP OF HYPER TERMINAL 80

COMPLETE CODE 83


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ABSTRACT

Saving energy is high on the agenda for consumers and businesses, but with most of

the electrical devices today, its difficult to know how much energy we are actually

using at any given point in time. Smart Energy Meter is a meter which helps the

consumers to know their day to day power consumption to better control their usage

and producers to manage production. This meter records consumption of electric

energy in intervals of hour or less. Smart meters enable two-way communication

between the meter and the central system. The proposed project comprises of

hardware design using a low-cost 8-bit P89C51RD2xx microcontroller and the

complete hardware design will be proposed .The Communication is through

SMS.They are two one is admin password and second is user. By this admin passwordthe cost per unit can be changed by the concerned officerThe system software driver

is also developed using embedded-C programming language in Keil Vision 4 IDE. .

Smart meters are also believed to be a less costly alternative to traditional interval or

time-of-use meters and are intended to be used on a wide scale with all customer

classes, including residential customers. The project also addresses about the various

debugging tools such as Keil Vision 4 C51 debugger and Flash magic tool 9.25

version used to test the implemented prototype.

Keywords: Embedded System , Micro controller , Cross-compiler and Debugging.


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CHAPTER-1


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CHAPTER - I

INTRODUCTION

Now-a-days electricity has become a basic need to humans. The consumptionof electricity has increased a lot compared to the past years. The theft of electricity

has also become a problem these days and there is no control over the loss due to theft

of electricity. In this project we present you the smart energy meter device used to

measure the consumption of the electricity by the individual and provide security

against theft of electricity.

A smart meter is usually an electrical meter that records consumption of

electric energy in intervals of an hour or less and communicates that information at

least daily back to the utility for monitoring and billing purposes. Smart meters enable

two-way communication between the meter and the central system. Unlike home

energy monitors, smart meters can gather data for remote reporting.

The term Smart meter often refers to an electricity meter, but it canincreasingly also mean a device measuring natural gas or water consumption. Smart

energy meter is software based, power efficient device that accurately tracks energy

consumption and performs computation. Meter readings can be transmitted to

distributors/utilities over wireless media; thus, eliminating the need of manual meter

reading collection process. The smart energy meter offers major benefits to both

customers and companies in terms of efficiency, reliability, and cost saving.

Imagine if you knew how much energy you were consuming at home at any

time of the day, and knew how much energy each device was using, will you stop

using those energy hog appliances? or use them at the time of the day when the

energy is cheapest? in the economy turmoil we are currently in, I believe all of us are

willing to make those small sacrifices to lower down the bill numbers at the end of themonth.

Smart energy meters are devices that will sit on your home, monitor energy

data from your electricity meter, and let you know how much energy you are using

this put more control on your hands on how you spend your energy at home.

Conventional electricity meters are normally hidden somewhere on a wall on the

basement, and the only time you realize how much energy youve been spending is

when the bill hit the door.

The new smart meters will provide Indian consumers with information

regarding energy consumption that was not previously available with a traditional

meter. This system will allow the easy disconnection of defaulted customers and

power connections from a remote site. The new smart system is also able to instantly

detect tampering with the power lines and sends signals to security personnel if

necessary. Utility employees will also have the ability to change a customers billing

method from pre paid to post paid in a matter of seconds, without having to physically

visit the meter.


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CHAPTER-2

CHAPTER- II


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LITERATURE SURVEY

2.1 MOTIVATIONIn the present scenario, the use of advanced technologies such as

digital metering has become extremely necessary to achieve greater efficiency, theft

reduction to reduce AT & C losses and to improve revenue collection. The utilities

and planners should now focus on best use of electronic technology to develop a full

smart system, which is capable of offering long term benefits and comprehensive

solutions in addition to theft reduction. In undeveloped and under developing

countries proper distribution of power has to be done. So its the duty of us, engineers

to develop the equipments to reduce the power losses and power thefts.

2.2 BACKGROUND

An electricity meter or energy meter is a device that measures the

amount of electric energy consumed by a residence, business, or an electrically

powered device. Electricity meters are typically calibrated in billing units, the most

common one being the kilowatt hour. Periodic readings of electric meters establish

billing cycles and energy used during a cycle. In settings when energy savings during

certain periods are desired, meters may measure demand, the maximum use of power

in some interval. In some areas, the electric rates are higher during certain times of

day, to encourage reduction in use. The billing of the electricity consumption in thesepresent days are done with human observation, but this project deals with the

communication for the proper billing through GSM without any human involvement.

Due to theft of electricity leads to power shut down in many of the rural areas in

India.

2.3 AIM:

To design and implement the smart energy meter by using 8051 micro

controller coded in embedded c program.


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2.4 Requirement Analysis:2.4.1 Hardware requirements

The components those are required for Smart Energy Meter projectis given below.

1. Micro Controller (P89C51R2FN).2. MAX 232.3. DB9 or RS232 connector.4. Power supply.5. 4*4 matrix keypad.6. LCD display.7. 555 timer IC8. IR sensors.

2.4.2 Software requirements

1. FLASH MAGIC Philips Serial ISP programming utility.2. KEIL Vision 4IDE C51 Embedded Cross Compiler.

2.5 SCOPE:

The scope of the project work is to introduce advanced technology in

converting dc voltage in to ac voltage and introducing smart energy metering concept.In future this project can be used to measuring natural gas or water

consumption. These meters can be connected to GSM module and data (i.e.

consumption) can be transmitted over GSM networks and the bills can be

automatically issued to the particular customer through SMS. By making small

modifications in the program (code) we can break the connection if user does not pay

the bills in time. There is no need for the electricity officials to visit the spot to

disconnect the connections i.e., everything can be controlled over the GSM module.

The user can also sell the electricity to the government which is created in his home

using solar cells. These meters can also be used as prepaid energy meters by slightly

modifying them.

2.6 Advantages:

More accurate bills.

Lower bills.

Track of energy usage.

Sell energy back to the grid.

Flexible tariffs.

No more meter readings.


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CHAPTER-3


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CHAPTER - III

DESIGN METHODOLOGY

3.1 Hardware System Design:

3.1. 1 Block level design of smart energy meter

The functional diagram of Smart Energy Meter using GSM or Hyper

Terminal is given below.

Fig 3.1 : Functional block diagram of Smart Energy Meter.


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3.1.2 SELECTION OF HARDWARE:

The hardware selected must be such a way that

Low cost

Low power consumption, small, fast

Continually reacts to changes in the systems environment Must compute certain results in real-time without delay

Simple design

Easy maintainability and interoperability

Bug-free/Correctness, safety, many more

3.1.3 DESIGN CONSIDERATIONS OF

MICROCONTROLLER

WHY P89C51RD2BN?

The system requirements and control specifications clearly rule out the use of16, 32 bit microcontrollers.

The P89C51RD2xx contains non-volatile 64KB Flash program memory that isboth parallel programmable and serial In-System and In-Application

Programmable.

In-System Programming (ISP) allows the user to download new code whilethe microcontroller sits in the application.

In-Application Programming (IAP) means that the microcontroller fetches newprogram code and reprograms itself while in the system. This allows for

remote programming over a modem link. A default serial loader (boot loader)

program in ROM allows serial In-System programming of the Flash memory

via the UART without the need for a loader in the Flash code. For In-

Application Programming, the user program erases and reprograms the Flash

memory by use of standard routines contained in ROM.

3.1.3.1 8051

The 8051 is an 8 bit microcontroller originally developed by Intel in 1980. It is

one of the most popular microcontrollers in the world for its high performance, rich

instruction set and low cost. This device is a Single-Chip 8-Bit Microcontroller

manufactured in an advanced CMOS process and is a derivative of the 8051

microcontroller family. The instruction set is 100% compatible with the 8051

instruction set. Three criteria in choosing the microcontrollers are as follows:

1. Meeting the computing needs of the task at hand efficiently and costeffectively.

2. Availability of software development tools such as compliers,assemblers, and debuggers.

3. Wide availability and reliable sources of the microcontroller.


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Some of the features that have made the 8051 popular are:

64 KB on chip program memory.

128 bytes on chip data memory (RAM). 4 register banks.

128 user defined software flags.

Four 8-bit data bus

16-bit address bus

32 general purpose registers each of 8 bits

16 bit timers (usually 2, but may have more, or less).

3 internal and 2 external interrupts.

Bit as well as byte addressable RAM area of 16 bytes.

Four 8-bit ports, (short models have two 8-bit ports).

16-bit program counter and data pointer. 1 Microsecond instruction cycle with 12 MHz Crystal.

8051 models may also have a number of special, model-specific features, such as

UARTs, ADC, Op Amps, etc...

3.1.3.2 Internal architecture of P89C51RD2XX

The P89C51RD2xx contains a non-volatile 8KB/16KB/32KB/64KB Flash

program memory that is both parallel programmable and serial In-System and In-

Application Programmable. In-System Programming (ISP) allows the user todownload new code while the microcontroller sits in the application. In-Application

Programming (IAP) means that the microcontroller fetches new program code and

reprograms itself while in the system.


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The internal architecture of P89C51RD2FN microcontroller with suitable

diagram

Fig 3.2: Internal architecture of P89C51RD2FN.

3.1.3.2.1 I/O ports:All 8051 microcontrollers have 4 I/O ports each comprising 8 bits which can

be configured as inputs or outputs. Accordingly, in total of 32 input/output pins

enabling the microcontroller to be connected to peripheral devices are available for

use.Pin configuration, i.e. whether it is to be configured as an input (1) or an output

(0), depends on its logic state. In order to configure a microcontroller pin as an input,it is necessary to apply logic zero (0) to appropriate I/O port bit. In this case, voltage

level on appropriate pin will be 0.

The 4I/O ports of 8051 are designated as port 0, port 1, port 2, and port

3. All these I/O ports have different functions and conditions while connecting to

external peripherals.

3.1.3.2.1. a Port 0 (P0)-The P0 port is characterized by two functions. If external memory is used then

the lower address byte (addresses A0-A7) is applied on it. Otherwise, all bits of this

port are configured as inputs/outputs. The other function is expressed when it is


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configured as an output. Unlike other ports consisting of pins with built-in pull-up

resistor connected by its end to 5 V power supply; pins of this port have this resistor

left out. If any pin of this port is configured as an input then it acts as if it floats.

Such an input has unlimited input resistance and undetermined potential. When the

pin is configured as an output, it acts as an open drain. By applying logic 0 to a port

bit, the appropriate pin will be connected to ground (0V). By applying logic 1, theexternal output will keep on floating. In order to apply logic 1 (5V) on this output

pin, it is necessary to built in an external pull-up resistor.

3.1.3.2.1. b Port 1 (P1)-

P1 is a true I/O port, because it doesn't have any alternative functions as is the

case with P0, but can be configured as general I/O only. It has a pull-up resistor built-

in and is completely compatible with TTL circuits.

3.1.3.2.1. c Port 2 (P2)-

P2 acts similarly to P0 when external memory is used. Pins of this port occupy

addresses intended for external memory chip. This time it is about the higher address

byte with addresses A8-A15. When no memory is added, this port can be used as a

general input/output port showing features similar to P1.

3.1.3.2.1. d Port 3 (P3)-All port pins can be used as general I/O, but they also have an alternative

function. In order to use these alternative functions, a logic one (1) must be applied to

appropriate bit of the P3 register. In terms of hardware, this port is similar to P0, with

the difference that its pins have a pull-up resistor built-in.

3.1.3.2.2 Interrupts controls:There are 7 kinds of interrupt controllers that 8051 handles. They are as

follows.

1. INT0 external interrupt.2. INT1 external interrupt.3. Timer 04. Timer 15. Reset.6. Transmitted interrupt (TXD).

7. Received interrupt (RXD).There are two types of external hardware interrupts. Pin 12 (P3.2) and pin 13

(P3.3) of the 8051, designated as INT0 and INT1, are used as external hardware

interrupts. Upon the activation of these pins, the 8051 gets interrupted in whatever it

is doing and jumps to the vector table to perform the interrupt service routines (ISR).

Timer 0 and timer 1 interrupts can be used in pooling method. In this method,

we have to wait until the TF is raised. The problem with this method is that the

microcontroller is tied down the controller. If the timer interrupt in the IE register is

enabled, whenever the timer rolls over, TF is raised, and the microcontroller is


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interrupted in whatever it is doing, and jumps to the interrupts vector table to service

the ISR.

Reset pin is an input pin and is active high (normally low). Upon applying a

high pulse to this pin, the microcontroller will reset and terminate all activities. This is

often referred to as power-on reset. In order for RESET input to be effective, it must

have a minimum duration of two machine cycles. In other words, the high pulse must

be high for a minimum of two machine cycles before it is allowed to go low. TXD

and RXD are serial communication interrupts.

3.1.3.2.3 BUS CONTROLS

The main bus controllers available in 8051 are ALE, EA, RST and PSEN.

ALE (Address Latch Enable):

Output pulse for latching the low byte of the address during an access to

external memory. In normal operation, ALE is emitted twice every machine cycle,

and can be used for external timing or clocking. Note that one ALE pulse is skipped

during each access to external data memory. ALE can be disabled by setting SFR

auxiliary.0. With this bit set, ALE will be active only during a MOVX instruction.

EA (External Access Enable/Programming Supply Voltage):

EA must be externally held low to enable the device to fetch code from

external program memory locations. If EA is held high, the device executes from

internal program memory. The value on the EA pin is latched when RST is released

and any subsequent changes have no effect. This pin also receives the programming

supply voltage (VPP) during Flash programming.

RST (Reset):

A high on this pin for two machine cycles while the oscillator is running

resets the device. An internal resistor to VSS permits a power-on reset using only an

external capacitor to VCC.

PSEN (Program Store Enable):

The read strobe to external program memory. When executing code from theexternal program memory, PSEN is activated twice each machine cycle, except that

two PSEN activations are skipped during each access to external data memory. PSEN

is not activated during fetches from internal program memory.

3.1.3.2.4 Memory organization

The 8051 has two types of memory and these are Program Memory and Data

Memory. Program Memory (ROM) is used to permanently save the program being

executed, while Data Memory (RAM) is used for temporarily storing data and

intermediate results created and used during the operation of the microcontroller.Depending on the model in use (we are still talking about the 8051 microcontroller


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family in general) at most a few Kb of ROM and 128 or 256 bytes of RAM is used.

All 8051 microcontrollers have a 16-bit addressing bus and are capable of addressing

64 kb memory. It is neither a mistake nor a big ambition of engineers who were

working on basic core development. It is a matter of smart memory organization

which makes these microcontrollers a real programmers goody.

3.1.3.2.4. a Program memory

The first models of the 8051 microcontroller family did not have internal

program memory. It was added as an external separate chip. These models are

recognizable by their label beginning with 803 (for example 8031 or 8032). All later

models have a few Kbyte ROM embedded. Even though such an amount of memory

is sufficient for writing most of the programs, there are situations when it is necessary

to use additional memory as well. A typical example is so called lookup tables. They

are used in cases when equations describing some processes are too complicated or

when there is no time for solving them. In such cases all necessary estimates andapproximates are executed in advance and the final results are put in the tables

(similar to logarithmic tables).

3.1.3.2.4. b Data memory

Data Memory is used for temporarily storing data and intermediate results

created and used during the operation of the microcontroller. Besides, RAM memorybuilt in the 8051 family includes many registers such as hardware counters and timers,

input/output ports, serial data buffers etc. The previous models had 256 RAMlocations, while for the later models this number was incremented by additional 128

registers. However, the first 256 memory locations (addresses 0-FFh) are the heart of

memory common to all the models belonging to the 8051 family.

3.1.3.2.5 Registers in 8051

In the CPU, registers are used to store information temporarily. That

information could be a byte of data to be processed, or an address pointing to the data

to be fetched. The vast majority of 8051 registers are 8- bit registers. In the 8051 thereis only one data type: 8 bits. With an 8-bit data type, any data larger than 8 bits must

be broken into 8- bit chunks before it is processed. The most widely used registers of

the 8051 are A(Accumulator), B, and SPF (special function registers) and PSW

(Program Status Word).

A register is a general-purpose register used for storing intermediate results

obtained during operation. Prior to executing an instruction upon any number or

operand it is necessary to store it in the accumulator first. All results obtained from

arithmetical operations performed by the ALU are stored in the accumulator. Data tobe moved from one register to another must go through the accumulator. In other

words, the A register is the most commonly used register and it is impossible to


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imagine a microcontroller without it. More than half instructions used by the 8051

microcontroller use somehow the accumulator. Multiplication and division can be

performed only upon numbers stored in the A and B registers. All other instructions in

the program can use this register as a spare accumulator (A).

3.1.3.2.5. a R Registers (R0-R7)

This is a common name for 8 general-purpose registers (R0, R1, R2 ...R7).

Even though they are not true SFRs, they deserve to be discussed here because of

their purpose. They occupy 4 banks within RAM. Similar to the accumulator, they are

used for temporary storing variables and intermediate results during operation. Which

one of these banks is to be active depends on two bits of the PSW Register. Active

bank is a bank the registers of which are currently used.

3.1.3.2.5. b SFR(Special Function Registers)

Special Function Registers (SFRs) are a sort of control table used for running

and monitoring the operation of the microcontroller. Each of these registers as well as

each bit they include, has its name, address in the scope of RAM and precisely

defined purpose such as timer control, interrupt control, serial communication control

etc. Even though there are 128 memory locations intended to be occupied by them,

the basic core, shared by all types of 8051 microcontrollers, has only 21 such

registers.

3.1.3.2.5.c PROGRAM STATUS WORD (PSW):

CY: Carry out from accumulator MSB of ALU operand

AC: Auxiliary carry for BCD operations

FO: General purpose

RS1 & RS0: For register banks selection ( RB0-RB3)

OV: Overflow flag

P: Parity of accumulator set by hardware to 1 if it contains odd no of 1s

Table 3.1.The contents of (RS1-RS0) enable the working register banks


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Carry flag:

Carry flag is set whenever there is carry out from the MSB. This flag is

after 8bit ADD/SUB operation. It can also be set to 1 or 0 directly using SETB C orCLR C

Auxiliary carry:

If there is a carry from D3 to D4 position during Add/Sub operation,

this bit will set. Otherwise, it is cleared. This flag is used for BCD operations.

Parity flag reflects the number of 1s in A. If A contains an odd number

of 1s, then P=1. Therefore P=0, if A has an even number of 1s.

Overflow flag:

This flag is set whenever the result of a signed number operation is too

large to be accommodated in 7 bits, causing the higher order bit to overflow into the

sign bit.

3.1.3.2.6 Oscillator:

The microcontroller used in this project, P89C51RD2FN requires a baud rate

of 9600. To acquire this baud rate, an 11.0592 MHz crystal must be connected

between 19th and 20th pins of controller. The determination of machine cycle

frequency and Baud rate is as follows.

MCF = (XTL freq / 12)

= (11.0592 * 10^6) / 12

= 921.6 KHz

Baud rate = MCF/32

= (921.6 10^3) / 32= 28800 Hz

RS 1 RS 0 BANKS AND REGISTERS

0 0 BANK 0 (00H-07H)

0 1 BANK 1 (08H0FH)

1 0 BANK 2 (10H-17H)

1 1 BANK 3 (18H-1FH)


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Where MCF = Machine Cycle Frequency,

XTL = Crystal.

To synchronize with timer1 (TH1) to set the baud rate as 9600 we need to set

those register value as -3 (decimal) or FD (Hexadecimal) so as to divide the baud rate

i.e.. 28800Hz should be dividing with the decimal value of TH1 to get 9600 value.

Fig 3.3: Oscillator Connections

C1, C2 = 33pF.

3.1.3.3 FEATURES

80C51 Central Processing Unit

On chip Flash Program Memory with In-System Programming (ISP) and In-Application Programming

Boot ROM contains low level Flash programming routines for downloadingvia the UART

Can be programmed by the end-user application(IAP)

Supports 6-clock/12 clock mode via parallel programmer(default clock modeafter Chip Erase is 12-clock)

Speed up to 20MHz with 6-clock cycles per machine cycle(40MHz equivalent performance), up to 33MHz with 12 clocks per machine


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cycle

RAM expandable externally to 64Kbytes

Four interrupt priority levels

Seven interrupt sources

Four 8-bit I/O ports

Full-duplex enhanced UART

8-Bit ALU , with 2 registers A & B

11 bit program counter & data pointer

8-Bit program status word

8 bit stack pointer

4registers banks, each containing 8 registers

16bytes , which may be addressed at bit level

80 bytes of general purpose data

Two 16 bit timer/counterT0 & T1

Control registersTCON, TMOD, SCON, PCON and IP & IE oscillator & clockcircuits.

3.1.4 SERIAL COMMUNICATION

3.1.4.1 Introduction

In order to connect microcontroller to a modem or a pc to modem a serial port

is used. Serial is a very common protocol for device communication that is standard

on almost every PC. Most computers include two RS-232 based serial ports. Serial isalso a common communication protocol that is used by many devices for

instrumentation; numerous GPIB-compatible devices also come with an RS232 port.

Furthermore, serial communication can be used for data acquisition in conjunction

with a remote sampling device.

Typically, serial is used to transmit ASCII data. Communication is completed

using 3 transmission lines. (1) Ground, (2) Transmit and (3) Receive. Since serial is

asynchronous, the port is able to transmit data on one line while receiving data on

another. Other lines are available for handshaking, but are not required. The important

serial characteristics are baud rate, data bits, stop bits, and parity. For two ports to

communicate, these parameters much match.

Serial communication is a popular means of transmitting data between acomputer and a peripheral device such as a programmable instrument or even another

one bit at a time, over a single communication line to a receiver. You can use this

method when data transfer rates are low or you must transfer data over long distances.

Serial communication is popular because most computers have one or more serial

ports, so no extra hardware is needed other than a cable to connect the instrument to

the computer or two computers together.

Any device you connect to the serial port will need the serial transmission

converted back to parallel so that it can be used. In serial communication, the data

will be sent from one system to another in bit by bit notation. Serial Ports come in two

sizes, there arethe D-Type 25 pin connector and the D-Type 9 Pin connector both

of which are male on the back of the PC, and thus you will require a female connector

on your device. The RS-232 and RS-485 come under serial communication.


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3.1.4.2 Baud Rate:

It is a speed measurement for communication. It indicates the number of bit

transfers per second. For example, 300 baud is 300 bits per second. When a clockcycle is referred it means the baud rate. For example, if the protocol calls for a 4800

baud rate, then the clock is running at 4800Hz. This means that the serial port is

sampling the data line at 4800Hz. Common baud rates for telephone lines are 12200,

28800 and 33600. Baud rates greater than these are possible, but these rates reduce

the distance by which devices can be separated. These high baud rates are used for

device communication where the devices are located together, as is typically the case

with GPIB devices.

3.1.5 HARDWARE DESIGN OF LCD

The LCD (Liquid Crystal Display) used to display the output to the user in the

form of GUI (Graphic User Interface) and a mono chromatic display. LCD used in

this project is JHD162A series.There are 16 pins in all. They are numbered from leftto right 1 to 16 (if you are reading from the backside). LCD shown above is marked to

indicate which the 1st pin was and which the 16th was.

In our project, we use a JHD162A LCD Display which has 2 rows and 16

characters. It contains internal 1 byte latch. It has a better contrast and a wider

viewing angle. To develop a protocol to interface this LCD with 89C51 first we have

to understand how they functions. These displays contain two internal byte-wideregisters, one for command and second for characters to be displayed. There are three

control signals called R/W, RS and EN. Select By making RS signal 0 you can send

different commands to display. These commands are used to initialize LCD, to

display pattern, to shift cursor or screen etc. You can see the markings right next to

1st and 16th pins. The 16by2 LCD with connections is as given below


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Fig 3.4: Pin configuration of LCD

3.1.5.1 LCD screen:-

LCD screen consists of two lines with 16 characters each. Each character

consists of 5*7 dot matrix. Contrast on display depends on the power supply voltage

and whether messages are displayed in one or two lines. For that reason, variable

voltage 0-Vdd is applied on pin marked as VEE. Trimmer potentiometer is usuallyused for that purpose. Some versions of displays have built in backlight (blue or green

diodes). When used during operating, a resistor for current limitation should be used

(like with any LE diode)

The main control pins on JHD162A are data lines, read or write and enable.

LCD is finding wide spread use replacing LEDs (seven segment LEDs or

other multi segment LEDs) because of the following reasons:1. The ability to display numbers, characters and graphics. This is in contrast to

LEDs, which are limited to numbers and a few characters.

2. Incorporation of a refreshing controller into the LCD, thereby relieving theCPU of the task of refreshing the LCD. In contrast, the LED must be refreshed

by the CPU to keep displaying the data.

3. Ease of programming for characters and graphics.4. These components are specialized for being used with the microcontrollers ,

which means that they cannot be activated by standard IC circuits. They are

used for writing different messages on a miniature LCD.


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Fig 3.5: LCD Display

3.1.5.1. a Data lines (D0-D7):The data lines are connected to the parallel port of the microcontroller. While

connecting the data lines to port0 no pull up resistors are required. These data lines

are used to pass the data from CPU i.e. controller to LCD internal memory and to pass

commands from LCD to CPU.Pin 7 is the Least Significant Bit (LSB) and pin 14 is

the Most Significant Bit (MSB) of the data inputs. If you want to display some

number or letter on the display, you have to input the appropriate codes for that

character on these pins. These pins are also used for giving certain commands to the

display like clearing the display or moving the cursor to a different location. Upon

giving the correct signals to the 3 control pins, the character codes or the commands

that you have given to the Data pins will be written to the display or executed by the

LCD respectively. To make it easier to give the appropriate inputs to these pin, i

recommend wiring up a DIP switch to these pins.

3.1.5.1. b Read and write:Generally, we always use the LCD to show things on the screen. However, in

some rare cases, we may need to read from the LCD what it is displaying. In such

cases, the R/W pin is used. However, this function is beyond the scope of post and

will not be explained. For all practical purposes, the R/W pin has to be permanently

connected to GND.

The timing diagram for write and read operation of JHD162A is as follows

Write operation:


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Fig 3.6: Timing diagram of write operation in LCD.

Read operation:

Fig 3.7: Timing diagram of read operation in LCD.

3.1.5.1. cEnable Pin:The enable pin has a very simple function. It is just the clock input for the

LCD. The instruction or the character data at the data pins (D0-D7) is processed by

the LCD on the falling edge of this pin. The Enable pin should be normally held atVcc by a pull up resistor. When a momentary button switch is pressed, the Pin goes

low and back to high again when you leave the switch. Your instruction or character

will be executed on the falling edge of the pulse. (i.e. the moment the switch closes).

3.1.5.1. d Reset pin:The LCD has basically two operating modes:Instruction mode and Character

Mode. Depending on the status of this pin, the data on the 8 data pins (D0-D7) is

treated as either an instruction or as character data. You have to activate the command

mode if you want to give an Instruction to the LCD. Example Clear the display,

Move cursor to home etc. You have to activate the character mode if you want to

tell the LCD to display some character. To set the LCD in Instruction mode, you set


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the 4th pin of the LCD (R/S) to GND. To put it in character mode, you connect it to

Vcc.

3.1.5.2 Features

RS232 compatible serial interface (2400 & 9600 Baud Selectable)

Externally selectable serial polarities (Inverted & Non-Inverted)

Serially controllable contrast and backlight levels

8 user programmable custom characters

16 Byte serial receive buffer

3.1.5.3 Pin Configuration:

There are pins along one side of the small printed board used for connection to

the microcontroller. There are total of 16 pins marked with numbers .Their function is

described in the table below:

Table 3.2 Pin Connections Description

Pins 18Description

Pins 9 -16Description

Pin1 Ground Pin9D2 (Not Used in

4bit operation)

Pin2 VCC (+5) Pin10D3 (Not Used in

4bit operation)

Pin3 Contrast Pin11 D4

Pin4Data/Comman

d (R/S)Pin12 D5

Pin5Read/Write

(W)Pin13 D6

Pin6 Enable (E1) Pin14 D7

Pin7

D0 (Not Used

in 4bit

operation)

Pin15VCC

(LEDSV+)

Pin8

D1 (Not Used

in 4bit

operation)

Pin16 Ground


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3.1.5.4 SPECIFICATIONS:

Number of Characters: 16 characters x 2 Lines

Character Table: English-European (RS in Datasheet)

Module dimension: 80.0mm x 36.0mm x 13.2mm(MAX) View area: 66.0 x 16.0 mm

Active area: 56.2 x 11.5 mm

Dot size: 0.56 x 0.66 mm

Dot pitch: 0.60 x 0.70 mm

Character size: 2.96 x 5.46 mm

Character pitch: 3.55 x 5.94 mm

LCD type: STN, Positive, Yellow/Green

Duty: 1/16

View direction: Wide viewing angle

To start with LCD the user should initialize it first which should be

programmed with its LCD commands. The LCD commands are given


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Table 3.3 Commands for LCD

CODE COMMANDS TO THE LCD

1 Clear display screen

2 Return home

4 Shift cursor to left

5 Shift display right

6 Shift cursor to right

7 Shift display left

8 Display off, cursor off

A Display off, cursor on

C Display on, cursor off

E Display on, cursor blinking

F Display off, cursor blinking

10 Shift cursor position to left

14 Shift cursor position to right

18 Shift entire display left

1c Shift entire display right

80 Force cursor to begin in 1strow

C0 Force cursor to begin in 2ndrow

38 2 lines &5x7 matrix


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Fig 3.8: LCD Interface with P89C51RD2XX

3.1.5.5 Functionality of LCD in this project:

LCD is used to display any message, like authentication. It displays the menu of operation, which contains two options automatic and

settings.

It displays the amount of power utilized and price for the relevant consumedpower.

It displays the user to send the data to HyperTerminal.

3.1.6 MAX 232:

Max232 IC is a specialized circuit which makes standard voltages as

required by RS232 standards. This IC provides best noise rejection and very reliable

against discharges and short circuits. MAX232 IC chips are commonly referred to as

line drivers.To ensure data transfer between PC and microcontroller, the baud rate and

voltage levels of Microcontroller and PC should be the same. The voltage levels of

microcontroller are logic1 and logic 0 i.e., logic 1 is +5V and logic 0 is 0V. But for

PC, RS232 voltage levels are considered and they are: logic 1 is taken as -3V to -25V

and logic 0 as +3V to +25V. So, in order to equal these voltage levels, MAX232 IC is

used. Thus this IC converts RS232 voltage levels to microcontroller voltage levels

and vice versa.


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3.1.6.1 Pin Configuration:

Fig 3.9: Pin diagram of MAX 232 IC

3.1.7 RS 232(Female Port)

RS-232 is the component which is used to connect system (pc) to

microcontroller.

RS-232 (Recommended Standard 232) is the traditional name for a series of

standards for serial binary single-ended data and control signals connecting between a

DTE(Data Terminal Equipment) and a DCE(Data Circuit- terminating Equipment).

It is commonly used in computer serial ports. The standard defines the electricalcharacteristics and timing of signals, the meaning of signals, and the physical size and

pinout of connectors.

RS232 is limited to point-to-point connections between PC serial ports and

devices. RS 232 hardware can be used for serial communication up to distances of 50

feet.

3.1.7.1 Voltage levels:

The RS-232 standard defines the voltage levels that correspond to logical one

and logical zero levels for the data transmission and the control signal lines.

For data transmission lines (TxD, RxD and their secondary channel

equivalents) logic one is defined as a negative voltage, the signal condition is called

marking, and has the functional significance. Logic zero is positive and the signal

condition is termed spacing.

Table 3.4: indicating voltage levels for DB 9 connector


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Logic level Voltage level

1 -10V

0 10V

3.1.7.2 PIN CONFIGURATION

Fig 3.10: DB9 Connector with pinout

3.1.7.3 DB9 INTERFACING WITH MICROCONTROLLER USING MAX 232:

Fig 3.11:DB9 interfacing with microcontroller using MAX 232


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3.1.8 Serial port connector:

The microcontroller is connected to the pc via a serial communication port.

The serial communication port is a combination of a female port and a male port. The

male port is connected to the DB-9 connector connected to the microcontroller while

the female port is connected to the serial port of the pc.

Fig 3.12: serial port connector

3.1.9 Design of keypad

The keypad used in this project is AT91. A 4x4 matrix keypad requiring eight

Input/output ports for interfacing is used. Rows are connected to Peripheral

Input/output (PIO) pins configured as output. Columns are connected to PIO pins

configured as input with interrupts.

Fig 3.13: 4x4 matrix Keypad


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Theinternal structure of keypad is as follows:

Fig 3.14: Internal structure of keypad

I/O configuration: Rows are connected to four PIO pins configured as

outputs. Columns are connected to four PIO pins configured as inputs with interrupts.

The idle state of these pins is high level due to four pull-up resistors. PIO interrupt is

generated by a low level applied to these pins (caused by a key pressed). Fouradditional PIO pins are configured as outputs to send the value of the pressed key to

LEDS.

Timer Counter Configuration: The Timer Counter is configured in

waveform operating mode with RC compare interrupt. The Timer Counter is

initialized to be incremented on internal clock cycles. The debouncing time is

programmable by initializing the RC compare register value according to the clock

source selected. A software trigger is used to reset the timer counter and start the

counter clock.

Interrupt: When a key is pressed, a low level is applied to the pincorresponding to the column associated to the key (pins configured as inputs with


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interrupts). A falling edge applied to a column pin creates a PIO interrupt. Then, the

processor executes the PIO interrupt subroutine (debouncing) and comes back to its

previous state (in the main program). After debouncing time, a RC compare timer

interrupt occurs and the processor then executes the timer interrupt subroutine

(decoding the pressed key) and comes back to its previous state (in the main

program).

Keyboard Operating Sequence

To detect a pressed key, the Microcontroller grounds all rows by

providing 0 to the output latch, and then it reads the columns. If the data read from

the columns isD3- D0=1111 no key has been pressed and the process is continued

until a key is detected. However if one of the columns bits is zero this means that a

key press has occur. For example if D2-D0=1101 this means that a key in D1 column

has been pressed after a key press is detected, the microcontroller will go through

the process of identifying the key. Starting with the top row, the microcontroller

grounds it by providing a low to row D0 only then it reads the columns. If the data

read is all once, no key in that row is achieved and the process is moved to the next

row. It ground the next row reads the column and checks for any zero. This process

continues until the row is identified. After identification of the row in which the key

has been press the next task is to find out which column the pressed key belongs to.

This should be easy since the micro control knows at any time which the row and

column are being accessed.

3.1.10 IR sensors and IC NE555 Timer:

The pair of IR sensors generally constitute of a photo transmitter and a photo

receiver. The photo transmitter generally a photo diode emits IR rays while the

receiver receives the IR rays. Whenever the transmission is blocked the sensor unit

sends a interrupt signal to the microcontroller which then increments the counter.

3.1.10.1 Photo transmitter:The photo transmitters are IR LEDs or photo diodes used to emit light.

IR LEDs are just like LEDs which emits IR rays. Since the IR rays are out of the

visible range we cannot observe the rays from the transmitter. A photodiodeis a typeof photo-detector capable of converting light into either current or voltage, depending

upon the mode of operation.

Photodiodes are similar to regular semiconductor diodes except that they may

be either exposed (to detect vacuum UV or X-rays) or packaged with a window or

optical fibre connection to allow light to reach the sensitive part of the device. Many

diodes designed for use specifically as a photodiode will also use a PIN junction

rather than the typical PN junction.

3.1.10.2 Principle of Operation:

A photodiode is a PN junction or PIN structure. When a photon of sufficientenergy strikes the diode, it excites an electron thereby creating a mobile electron and a


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positively charged electron hole. If the absorption occurs in the junction's depletion

region, or one diffusion length away from it, these carriers are swept from the junction

by the built-in field of the depletion region. Thus holes move toward the anode, and

electrons toward the cathode, and a photocurrent is produced.

3.1.10.2. a Design parameters

1. Transistor2. TCRT5000 IR transmitter3. TCRT5000 IR receiver4. 100ohms , 220ohms resistor (near transmitter)5. 22ohms,4.7ohms resister (near receiver)

Fig 3.15: IR Transmitter Circuit diagram

Fig 3.16: IR Receiver Circuit diagram


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3.1.10.3 Applications:

Photo diodes are used in

Consumer electronic devices such as compact disc players, smokedetectors, and the receivers for remote controls in VCRs and television.

Accurate measurement of light intensity. Detectors for computed tomography (coupled with scintillators) or

instruments to analyze samples (immunoassay), pulse oximeters.

Optical communications and in lighting regulation.

Astronomy, spectroscopy, night vision equipment and laser range finding.

3.1.10.4FEATURES:

= 940 nm

Chip material =GaAs with AlGaAs window

Medium Emission Angle, 40

High Output Power Package material and color: Clear, untinted, plastic

Ideal for remote control applications

3.1.10.5 IR Receiver:

IR receiver is used to receive the signals transmitted by the IR transmitter.IR

receiver is similar to a N-P-N transistor. It is a three terminal device but looks like a

two terminal device a base is connected internally. It is a nothing but a

phototransistor.

Fig 3.17: IR receiver

3.1.10.6 Phototransistors:

Phototransistors also consist of a photodiode with internal gain. Aphototransistor is in essence nothing more than a bipolar transistor that is encased in a

transparent case so that light can reach the base-collector junction.

3.1.10.7 Principle of Operation:

The electrons that are generated by photons in the base-collector junction are

injected into the base, and this current is amplified by the transistor operation. Note

that although phototransistors have a higher responsiveness for light they are unable

to detect low levels of light any better than photodiodes. Phototransistors also have

slower response times.


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3.1.11 IC NE555 TIMER:

The 555 timer IC is an integrated circuit used in a variety of timer, pulse

generation and oscillator applications. The full part numbers were NE555

(commercial temperature range, 0 C to +70 C). It has been hypothesized that the

555 got its name from the three 5 k resistors used internally.

Depending on the manufacturer, the standard 555 package includes over 20

transistors, 2 diodes and 15 resistors on a silicon chip installed in an 8-pin mini dual-

in-line package (DIP-8).

Fig 3.18: 555 Timer

The 555 has three operating modes:

3.1.11.1 Monostable mode:In this mode, the 555 timer functions as a "one-shot" pulse generator.

Applications include timers, missing pulse detection, bounce free switches, touch

switches, frequency divider, capacitance measurement, pulse-width modulation

(PWM) and so on.

3.1.11.2 Astable mode:

Free running mode: the 555 can operate as an oscillator. Uses include LEDand lamp flashers, pulse generation, logic clocks, tone generation, security alarms,

pulse position modulation and so on. Selecting a NTC as timing resistor allows the

use of the 555 in a temperature sensor: the period of the output pulse is determined by

the temperature. The use of a microprocessor based circuit can then convert the pulse

period to temperature, linearize it and even provide calibration means.

3.1.11.3 Bistable mode or Schmitt trigger:The 555 can operate as a flip-flop, if the DIS pin is not connected and no

capacitor is used. Uses include bounce free latched switches.

3.1.11.4 Features of NE555 Timer:

Timing is from microseconds through hours

O/p is compatible with CMOS, DTL and TTL

High Temperature Stability

Duty cycle is Adjustable

Mono-stable and Astable operations

3.1.11.5 Specifications of NE555Timer:


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Supply voltage VCC 4.5 to 15V

Supply current (VCC=+5V) 3 to 6mA

Maximum O/P Current 200mA

Power Dissipation 600mA

Power consumption (minimum operating) 30mW@ 5V,225mW@15V

Operating temperature 0 to 70 C

3.1.12 Resistors:

A resistor is a two-terminal passive electronic component that implements

electrical resistance as a circuit element. When a voltage V is applied across the

terminals of a resistor, a current I will flow through the resistor in direct proportion to

that voltage. This constant of proportionality is called conductance, G. The reciprocal

of the conductance is known as the resistance R, since, with a given voltage V, a

larger value of R further "resists" the flow of current I as given by Ohm's law:

Fig 3.19: Resistors

Practical resistors can be made of various compounds and films, as well asresistance wire (wire made of a high-resistivity alloy, such as nickel-chrome).

Resistors are also implemented within integrated circuits, particularly analog devices,

and can also be integrated into hybrid and printed circuits.

3.1.13 Capacitors:

A capacitor (formerly known as condenser) is a device for storing electric

charge. The forms of practical capacitors vary widely, but all contain at least two

conductors separated by a non-conductor. Capacitors used as parts of electrical

systems, for example, consist of metal foils separated by a layer of insulating film.


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A capacitor is a passive electronic component consisting of a pair of

conductors separated by a dielectric (insulator). When there is a potential difference

(voltage) across the conductors, a static electric field develops across the dielectric,

causing positive charge to collect on one plate and negative charge on the other plate.

Energy is stored in the electrostatic field. An ideal capacitor is characterized by a

single constant value, capacitance, measured in farads. This is the ratio of the electriccharge on each conductor to the potential difference between them.

Fig 3.20: capacitors

Capacitors are widely used in electronic circuits for blocking direct current

while allowing alternating current to pass, in filter networks, for smoothing the output

of power supplies, in the resonant circuits that tune radios to particular frequencies

and for many other purposes.

The capacitor is a reasonably general model for electric fields within electric

circuits. An ideal capacitor is wholly characterized by a constant capacitance C,

defined as the ratio of charge Qon each conductor to the voltage Vbetween them:

3.1.14 Crystal oscillator:

A crystal oscillator is an electronic oscillator circuit that uses the mechanicalresonance of a vibrating crystal of piezoelectric material to create an electrical signal

with a very precise frequency. This frequency is commonly used to keep track of time

(as in quartz wristwatches), to provide a stable clock signal for digital integrated

circuits, and to stabilize frequencies for radio transmitters and receivers. The most

common type of piezoelectric resonator used is the quartz crystal, so oscillator circuits

designed around them became known as "crystal oscillators."


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Fig 3.21: crystal oscillator

Quartz crystals are manufactured for frequencies from a few tens of kilohertz

to tens of megahertz. More than two billion (2109) crystals are manufactured

annually. Most are used for consumer devices such as wristwatches, clocks, radios,

computers, and cell phones. Quartz crystals are also found inside test and

measurement equipment, such as counters, signal generators, and oscilloscopes.

3.2 Software design:

3.2.1 Liquid Crystal Display

3.2.1.1 Initializing the LCD

Before you using the LCD, the program must initialize and configure it. This

is accomplished by sending a number of initialization instructions to the LCD.The first instruction to send is the no of data for the LCD i.e., with an 8-bit or

4-bit data bus. The other thing need to specify is display matrix; in the selected LCD

it is a 5x8 dot character font. These two options are selected by sending the command

38h to the LCD as a command. The command can give to the LCD by invoking the

pre defined function call lcdcmd with passing parameters value of 38H, the syntax for

the same can be given like lcdcmd (0x38).

3.2.1.2 Checking the busy status of the LCD

3.2.1.2.1 Busy Flag (BF):

When the busy flag is high or 1 the module is performing an internal

operation and the next instruction will not be accepted. The RS=0 is used to check the

Busy flag bit too see if the LCD is ready to receive information. The Busy flag is D7

and can be read when R/W = 1 and RS = 0, as follows: if R/W = 1, RS= 0.When

D7=1 (busy flag), the LCD is busy taking care of internal operations and will not

accept any new information. When D7=0, the LCD is ready to receive new

information.


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3.2.1.2.1.1 Busy flag flowchart

Fig 3.22: Busy flag flowchart

3.2.1.2.2.1 Writing command to the Display

To give a command to perform some special functions like move to position,

clear LCD ,blink the curser etc. the instruction sequence must follow like first

instruction must be set in the data bus set RS signal to logic 0 and enabling the LCD

will receive the data . After finishing the instruction sequence the application must

wait till the LCD completes the instruction by checking the LCD Busy status.

3.2.1.2.2.2 Writing command display flow chart


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Fig 3.23: Writing command display flow chart

1. Check the Busy flag bit

2. Set the instruction in data lines (if it is writing)

3.Set RS bit to logic 1 to 0

4. Set R/W bit is to low

6. Set En line to high7. Set line to low

3.2.1.2.4.1 Displaying the data in to the LCD

Writing the string in the LCD, to get the result first the address at which the

string has to display on the screen is given as command followed by displaying the

individual characters as LCD data .That finishes the data to be display in the LCD.

The complete flow chart representation of LCD working process is as follows:


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Fig 3.24: Flow chart for the LCD function.

3.2.2 KEYPAD:

Start

RS=0

E=1

Delay

E=0

LCD

Busy

RS=0

E=1

Delay

P0=command

LCD

Busy


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3.2.2.1 FLOW CHART OF KEY BOARD SCANNING ALGORITHM

Fig 3.25: Flow Chart of Key Board Scanning Algorithm


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COMPLETE FLOW CHART OF SMART ENERGY METER


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CHAPTER - 4


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CHAPTER4

IMPLEMENTATION

4.1 HARDWARE IMPLEMENTATION

4.1.1 Complete Schematic of Smart Energy Meter

Fig 4.1: Complete schematic of Smart Energy Meter


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4.1.2 Connections of P89C51RD2FN

The pin configuration of P89C51RD2XX:-

Fig 4.2: Pin diagram of P89C51RD2FN

In this project the microcontroller is connected to MAX232, LCD, Keypad, sensors.

The connections of microcontroller are given briefly below:

Pin1 to pin8 (Port 0) of controller are connected to the data lines of keypad(D0-D8).

The reset pin is connected to the 9thpin (RST) of P89C51RD2FN, as it is usedfor set reset the program.

While the 10pin is connected to the 12thpin of MAX232. 11thpin of controller is connected to the 11thpin of MAX232. The interrupt given by the IR sensors from the 555IC timer should be

connected to the 12thpin i.e. INTO pin of controller.

13thpin is used as an external interrupt, but here in this project there is no usewith this pin.

The crystal oscillator which gives a frequency of 11.0592 MHz for therequired Baud rate of 9600Hz to the microcontroller. This crystal oscillator is


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connected in between 18th (XALT 1) and 19th (XALT 2) pins of

P89C51RD2FN controller.

The 20thpin of controller is grounded. The pins from 21st to 28th (port 2 data lines) are used for the external

peripheral connections.

The 29thpin is connected to an on-off switch so as to dump and execute theprogram. Whenever the PSEN pin is connected to ground then we can execute

the last dumped program, likewise when 29 th pin is connected to VCC then

code can be dumped into the controller.

Address Latch Enable pin (30thpin) of controller is connected to the groundhence no connections need not to be given to this pin.

External Access Enable or programming supply voltage should be latchedwhen RST is released and any subsequent changes have no effect. This pin

also receives the programming supply voltage (VPP) during Flash

programming. Hence the pin 31stmust be connected to high i.e. VCC.

Port0 (pins 32 to 39) are connected to LCD in this project. But these should be

connected to other peripherals through pull up resistors.

4.1.3 Pin connections of LCD

The LCD used for output display is JHD162A series. The detailed connections

of LCD is described briefly as

The 1st and 2nd pins of JHD162A LCD are connected to ground and highvoltage VCC respectively.

3rdpin of LCD is connected to the centre pin of the potentiometer or variableresistor so as to adjust the contrast of LCD.

The 4th, 5th, 6thpins are connected to 26th(P 2.5), 27th(P 2.6), 28th(P 2.7) pinsof the microcontroller respectively.

The 7thto 14thpins are data pins and are connected to the 39 th(P 0.0) to 32nd(P 0.7) pins of the microcontroller respectively.

The 15thand 16thpins are used for backlight purpose. 15 thpin is connected toVCCand 16

thpin to ground.


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Fig 4.3: connection of LCD with P89C51RD2FN.

4.1.4 KEYPAD CONNECTIONS:

The keypad used is 4*4 keypad

The pins 1, 2, 3, 4 which are connected to columns of the keypad areconnected to 1, 2, 3, 4(P1.0 to P1.3) pins of the microcontroller

respectively.

The pins 5, 6, 7, 8 which are connected to rows of the keypad areconnected to 5, 6, 7, 8(P1.4 to P1.7) pins of the microcontroller

respectively.

4.1.5 MAX232 AND DB9 CONNECTION:

MAX232 and DB9 connector plays a key role in program dumping and

communication between project kit to the PC host.

Capacitor C10 of capacitance 1Uf is connected across 1st and 3rd pins ofMAX232 and C9 of capacitance 1Uf is connected in between 4thand 5thpins.

Charge pump capacitors are required for the MAX232 to work it as voltagelevel shifter. The charge pump capacitors used here are C7 and C8 whose

capacitance is 1Uf. C7 is connected between 6thpin and ground, while C8 is

connected across 2ndpin of MAX232 and Vcc.

12th and 11th pins of MAX232 are connected to the 10th and 11th pins of

P89C51RD2FN controller respectively. These acts as a transmitter and

receiver for the data flow.

To connect the MAX232 to the PC host we require a medium named as DB9

connector. The 2ndand 3rdpin of the DB9 connector should be connected tothe 14thand 13thpins of MAX232 respectively. While the 5thpin is grounded.


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4.1.6 IC555 TIMER and IR transmitter connections:

The sensor is designed using a 555 timer, a IR transmitter and a IRreceiver.

The 555 timer is operated in astable mode of operation.

The 1stpin is grounded.

The 2ndpin and 6thpin are shorted, 2ndpin is connected to VCCthrough

the 10K and 220K pot, IR receiver is connected to 2ndpin in reverse

bias.

The pin 3 of 555 timer is an output pin which is connected to the 12th

pin (P 3.2) of the microcontroller.

The 4th pin and 8th pin are shorted, 8th pin is connected to VCC and0.1f capacitor is connected between 8thpin and ground.

The 5thpin is grounded through 0.01f capacitor.

The IR transmitter is connected between VCCand ground through 270ohm resistor. It is connected in forward bias.

If there is obstruction between transmitter and receiver, the receiveroutput gives 3V to 5V.

Whenever there is an obstruction of current between transmitter andreceiver, the current passed to receiver decreases and hence the voltage

across voltage divider decreases. As a result a short pulse is applied to

the port pin of the 8051 microcontroller. On receiving a pulse from the

sensor circuit, the controller increments the counter which indicates the

consumption of electricity.

The IR sensor implementation using 555 timer is shown in figure below:

Fig 4.4: connection of IR sensors with 555 timers.


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CHAPTER - 5


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CHAPTER-5

SOFTWARE IMPLEMENTATION

This chapter explores some real world applications of the

P89C51RD2xx, and also includes how to interface the P89C51RD2xx to

devices such as an LCD and a keyboard and its software functionality

using embedded C language.

5.1 JHD162A LCD INTERFACING

5.1.1Initializing the LCD

Before you using the LCD, the program must initialize and configure it. Thisis accomplished by sending a number of initialization instructions to the LCD.

The first instruction to send is the no of data for the LCD i.e., with an 8-bit or

4-bit data bus. The other thing need to specify is display matrix; in the selected LCD

it is a 5x8 dot character font. These two options are selected by sending the command

38h to the LCD as a command. The command can give to the LCD by invoking the

pre defined function call lcdcmd with passing parameters value of 38H ,the syntax for

the same can be given like lcdcmd(0x38).

5.1.2 The initialization sequence code can be given as follows:

lcdcmd(0x38); // 2 lines and 5x7 matrix

lcdcmd(0xC0); // force cursor to begging of 2ndline

lcdcmd(0x0E); // display on, cursor blinking

lcdcmd(0x01); //clear display screen

lcdcmd(0x06); // increment cursor (shift cursor right)

lcdcmd(0x80); // force cursor to begging of 1stline

5.1.3 Checking the busy status of the LCD

Busy Flag (BF):void lcdready(void)

{

busy=1;

rs=0; //Register select command

rw=1;

while(busy==1) // if Bit (D7) high, LCD still busy

{

en=0; // Finish the command

MSDelay(1);

en=1; // Start LCD command


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}

}

5.1.4 Writing command to the Display

void lcdcmd (unsigned char value) // LCD command initiation routine

{Lcdready(); // wait till the LCD executes the instruction

ldata=value; // Set the value(instruction) in Data bus

rs=0; // register select as command

rw=0;

en=1; // set the enable command

MSDelay(1);

en=0; // Reset the enable command

}

5.1.5 Writing Data to Display

void lcddata (unsigned char value) // LCD data placing routine{

lcdready(); // wait till the LCD executes the instruction

ldata = value; // Set the value(Data) in Data bus

rs=1; //register select as data

rw=0; //read command

en=1; // Send Enable Signal to LCD

MSDelay(1); // This Function Gives Approximate Delay required For LCD

Initialization

en=0; //Reset the Enable Command

}5.1.6 Displaying the data in to the LCDvoid WriteString(unsigned char count,unsigned char *MSG)

{

unsigned char i;

for(i=0;i


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unsigned char KeyTest(void)

{

P1=0xF0;

while (1)

{

while(P1!=0xF0){

r0=0; r1=1;r2=1;r3=1;

if(c0==0)

return '1';

else if(c1==0)

return '4';

else if(c2==0)

return '7';

else if(c3==0)

return 'E';

r1=0; r0=1;r2=1;r3=1;if(c0==0)

return '2';

else if(c1==0)

return '5';

else if(c2==0)

return '8';

else if(c3==0)

return '0';

r2=0; r0=1;r1=1;r3=1;

if(c0==0)

return '3';

else if(c1==0)

return '6';

else if(c2==0)

return '9';

else if(c3==0)

return 'F'; // Down Arrow

r3=0; r0=1;r1=1;r2=1;

if(c0==0)

return 'A';

else if(c1==0)return 'B';

else if(c2==0)

return 'C'; // Redail

else if(c3==0)

return 'D'; // Enter

} } }

5.1.8 SENSORS:

sbit sense=P3^2; //energy meter

void _Up() interrupt 0


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{

Flag=sense;

if(Flag==1)

{

Count++;

Flag=0;}

}


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CHAPTER - 6

Chapter

6


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DEBUGGING TECHNIQUES

6.1 Keil uvision Debugger

6.1.1 Introduction to Keil IDE

Keil is a compiler that has 3 windows, project window, edit window,

and build or command window Schematic. Today, Keil Software provides a broad

range of development tools for the embedded systems marketplace. Their products

include ANSIC compilers, macro assemblers, debuggers, linkers, library managers,

and real-time operating systems.

. It was then that Keil Software implemented the first C compiler designed

from the ground-up specifically for the 89C51 microcontroller.

6.1.2 Features

1. Nine basic data types, including 32-bit IEEE floating-point2. Flexible variable allocation with bit, data, bdata, idata, xdata, and pdata

memory types

3. Interrupt functions may be written in C4. Full use of the 8051 register banks5. Complete symbol and type information for source-level debugging

6. Bit-addressable data objects7. Built-in interface for the RTX51 real-time kernel8. Support for dual data pointers on Atmel, AMD, Cypress, Dallas

semiconductor, Infineon, Philips, and Transcend microcontrollers

9. Support for Phillips 8xC510,8xC71,and 8xC752 limited instruction sets10.Support for the Phillips 80C51 arithmetic unit.

The Keil 8051 Development Tools are designed to solve the complex problemsfacing embedded software developers.

When starting a new project, simply select the microcontroller you use from theDevice Database and the vision IDE sets all compiler, assembler, linker, and

memory options for you.

Numerous example programs are included to help you get started with mostpopular embedded 8051 devices.

The Keil Vision Debugger accurately simulates on-chip peripherals (CAN,UART, SPI, Interrupts, I/O Ports, A/D Convertor, D/A convertor, and PWM

Modules) of your 8051 device. Simulation helps you understand hardware

configurations and avoids time wasted on setup problems. Additionally, with


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simulation, you can write and test applications before target hardware is

available.

When you are ready to begin testing your software application with target

hardware, use the MON51, MONADI, or FlashMON51 Target Monitors, the

ISD51 In-system Debugger, or the ULINK USB-JTAG Adapter to download

and test program code on your target system.

6.1.3 Steps to follow while writing a program in keil:

1. Install Keil Micro Vision in your PC, Then after Click on that Keil UVision icon.

After opening the window go to toolbar and select Project Tab then close previous

project.

2. Next select New Project from Project Tab.

3. Then it will open Create New Project window. Select the path where you want tosave project and edit project name.

4. Next it opens Select Device for Target window, it shows list of companies and

here you can select the device manufacturer company.

5. For an example, for your project purpose you can select the chip as 89c51rd2xx

from Philips Group. Next Click OK Button, it appears empty window here you can

observe left side a small window i.e., Project Window. Next create a new file.

6. From the Main tool bar Menu select File Tab and go to New, then it will open a

window, there you can edit the program.

7. Here you can edit the program as which language will you prefer either Assembly

or C.

8. After editing the program save the file with extension as .c or .asm, if you write

a program in Assembly Language save as .asm or if you write a program in C

Language save as .c in the selected path.

9. Then after saving the file, compile the program. For compilation go to project

window select source group and right click on that and go to Add files to

Group.

10. Here it will ask which file has to add. For an example here you can add test.c as

you saved before

11. After adding the file, again go to Project Window and right click on your c file

then select Build target for compilation. If there is any Errors or Warnings in

your program you can check in Output Window that is shown bottom of the Keil

window.

12. Here in this step you can observe the output window for errors and warnings

13. If you make any mistake in your program you can check in this slide for which

error and where the error is by clicking on that error


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14. After compilation then next go to Debug Session. In Tool Bar menu go to

Debug tab and select Start/Stop Debug Session.

15. Write a program for Leds Blinking. LEDS are connected to PORT-1. you can

observe the output in that port.

16. To see the Ports and other Peripheral Features go to main toolbar menu and select

peripherals.

17. In this slide see the selected port i.e., PORT-1.

18. Start to trace the program in sequence manner i.e, step by step execution and

observe the output in port window

19. After completion of Debug Session Create an Hex file for Burning the Processor.

Here to create a Hex file goes to project window and right click on Target next

select Option for Target.

20. It appears one window; here in target tab modify the crystal frequency as you

connected to your microcontroller.

21. Next go to Output tab. In that Output tab click on Create HEX File and then

click OK.

22. Finally Once again compile your program. The Created Hex File will appear in

your path folder

6.2 Flash magic

Flash Magic is a PC tool for programming flash based microcontrollers

from NXP using a serial or Ethernet protocol while in the target hardware.

6.2.1 Features

Straightforward and intuitive user interface

Read any section of Flash and save as an Intel Hex file.

Program security bits

Automatic verifying after programming

Five simple steps to erasing and programming a device and setting key options

Fills unused Flash to increase firmware security

Check which Flash blocks are blank or in use with the ability to easily eraseall blocks in use

Reprogram the Boot Vector and Status Byte with the help of confirmationfeatures that prevent accidentally programming incorrect values.


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Display the contents of Flash in ASCII and Hexadecimal formats

Single-click access to the manual, Flash Magic home page and NXPMicrocontrollers home page

Use high-speed serial communications on devices that support it.

Command Line interface allowing use in IDEs and Batch Files.

Supports half-duplex communications for many devices

Verify Hex Files previously programmed

Control the DTR and RTS RS232 signals to place the device into Boot ROMand Execute modes automatically (requires hardware support)

Send commands to place the device in Boot loader mode

Powerful, flexible Just In Time Code feature. Write your own JIT Modules togenerate last minute code for programming, for example serial number

generation.

Displays information about the selected Hex File, including the creation andmodification dates, flash memory used, percentage of the current device used

Read the device signature

Build your own Flash Magic based applications using the DLLs for C, C++,Python

Build your own Flash Magic based applications using .NET languages(Windows only)

6.3 Null MODEM checking (Hyper Terminal)

Debugging of 8051 application can be very easy if we able to send debug

information to serial port of PC. And its output can be seen on HyperTerminal (in

Windows ) or Minicom ( in Linux ). We can display content of any variable, memory

location etc. We can also print other useful information on serial terminal which could

replicate the flow of the code.

The Microsoft HyperTerminal terminal emulation application can display

messages sent from the serial port of a SDB or hardware platform. You can use these

messages to verify whether the boot loader is on the SDB, to discover problems that

may occur when the SDB boots, and to obtain the name of the SDB for use in the

Platform Builder integrated development environment (IDE).

To configure HyperTerminal for BSPs

1. From the Windows Startmenu, choose AllPrograms, and thenchoose Accessories.


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2. Choose Communications, and then choose HyperTerminal.3. In the Connection Descriptiondialog box, in the Namebox, type a name for

the connection to your SDB.

4. From the Iconlist, choose an icon to represent your connection, and thenchoose OK.

5. In the Connect Todialog box, in the Connect usingbox, choose thecommunications (COM) port on the development workstation through which

you want to receive messages from the SDB.

The COM port that you choose must be the COM port on the development

workstation to which you attach the null modem cable.

6. Choose OK.7. In the COMProperties dialog box, modify the settings for

your connection so that the settings are correct for your BSP.

6.4 Hardware debugging techniques

In the context of hardware debugging techniques, we are going to observe the

different types of error and checking of the components in the project.

While considering the microcontroller, the voltage level at 30th pin must be

1.6V because of the following reason

1. The voltage supply to the kit or mainly processor is 5V.2. The duty cycle of the microcontroller is 33%

Duty Cycle = T on / (T on+T off)

Where T off = 2* T on

DC = 1/ (1+2)

DC= 0.333

Hence the voltage at 30th pin should be product of Duty Cycle and voltage

supply VCC. Therefore the voltage should be 1.6V.

3. The voltage levels at 2ndand 6thpins of MAX232 should be -10V and+10V respectively.

CONCLUSION

Since the inception of electricity deregulation and market-driven pricing

throughout the world, utilities have been looking for a means to match consumption

with generation. Smart meters are also believed to be a less costly alternative to

traditional interval or time-of-use meters and are intended to be used on a wide scale

with all customer classes, including residential customers

Supporting Consumers: a) An end to estimate bills, which are a major source of

complaints for many customers b)A tool to help consumers better manage their

energy use - smart meters with a display can provide up to date information onelectricity consumption in the currency of that country and in doing so help people to


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better manage their energy use and reduce their energy bills and carbon emissions .c)

voltage levels, and power events can be tracked and logged across the entire customer

base.

Supports Power Grid: The Ability to remotely turn power on or off to a customer,

read usage information from a meter, detect a service outage, detect the unauthorizeduse of electricity, know the maximum amount of electricity that a customer can

demand at any time. It is projected to reduce the staff required to read meter data

across the customer base.

Supports Environment: The billing is through HyperTerminal or GSM, so lot of

paper can be saved .So Cutting of Trees can be avoided . It is believed that billing

customers by time of day will encourage consumers to adjust their consumption habits

to be more responsive to market prices thereby saving the power by which natural

resources are protected.

It is a Greener, Smarter, New era of Energy Use.

RESULTS

Now the most awaited part of the program is final result which can be seen

by the following steps once the kit is ready.

Give 5V Power supply and connect the pc with serial connector to DB9connector

Now ON the circuit.

We can see on the LCD display WELCOME RMCE SMART ENERGYMETER and press enter (E) in keypad.

The LCD asks for user id and password. Once they are correct, it showsAUTHENTICATED.

Now main menu is displayed having options:1.Readings2. Settings

If 1 is pressed the LCD displays initial count value as 0000

When one interrupt is detected, go to readings and then the countvalue is incremented.

Then 2 options will be displayed:1.Send 2.Exit

If 1 is pressed, the data i.e. count value and unit price will bedisplayed on the PC through HyperTerminal.

Once data is sent, we will get a reply DATA SENT.

If option 2 is pressed i.e. SETTINGS we can change USER ID,PASSWORD and UNIT PRICE AND PHONE NO. But it can be

changed only by the administrator only.

7. BIBILOGRAPHY:


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