final report (1)
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CHAPTER 1
1.1 INTRODUCTION
This note is to describe about the setup and configuration of the
multimodal security system Multimodal Security System For Bank
Locker and Secure Locations with GSM Alert and Remote Alarm
Activation using PIC16F877A microcontroller. Here each locker is
provided with a simple and cost efficient digital system that controls the
lock to the locker instead of a key. The digital system is connected to a
computer in the bank that in turn has the database of the customers with
various details of them including their fingerprints. The communication
between the computer and the microcontroller is provided via an RS-232
drivers/receiver and 74157 data multiplexer.
The pic microcontroller is used to interface the number of
components installed in the system such as the pc, pc interfacing circuit,
data multiplexer, gsm modem, electronic lock, LCD and alarm. This
system is designed using Embedded systems programming and has been
tested. This system thus helps provide secured bank locker systems thus
preventing theft by unauthorised persons accessing the lockers.
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1.2 LITERATURE SURVEY
1.2.1 EXISTING SYSTEM:
Most of the banks today use two keys to open the lockers. If the
bank manager wants to open the locker, two keys must be inserted in the
locker. One of which belongs to manager and second belongs to another
employee of the bank( cashier). The above system has many drawbacks,
Both the bank employees must have to present with the keys to open the
locker which is not secure. There is possibility of loosing the key which
makes the system insecure to the customer. The system is unabled to
match with today fast moving digital world. The keys can be
manufactured exactly similar to original ones which is very unsafe.
The Security Deposit will be kept under Bank's lien in respect of
rentals and other dues on locker services viz. breaking open or
replacement of lock in case of loss of keys etc. Locker facility is provided
by the bank at its selected branches. The lockers are allotted on first come
first served basis to the customers only. At the time of hiring the locker,
bank will obtain a minimum-security deposit in the form of FDR from
the lessee for the amount which would cover 3 years rent and the charges
for breaking open the locker in case of such eventualities.
An acknowledgement will be issued by the bank for fixed deposit
to be kept as security deposit. Loss of key should be immediately
informed to the bank branch. The bank is responsible for any loss.
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The locker is to be operated during the specified timing displayed at the
branches. You can operate the locker either singly or jointly, but only one
key is allotted per customer, while the other key remains with the bank.
Storing too much jewellery and valuables in the house at times
becomes a security issue and an impediment in case of natural calamities.
Bank lockers offers you, a safe, trustworthy space to store your valuables,
jewellery , documents and other things dear to you.
In bank lockers and others secure locations the existing system that
is used to protect the safe and lockers is the mechanical lock system. This
lock system uses a key to unlock the lockers. Thus the existing system is
not a reliable means as the mechanical locks are not secure and can be
broken by any means. And thus making and the bank lockers and other
secure locations, such as, jewelry shops, houses, etc..,. More unsecure.
Considering all these drawbacks we have designed a bank locker
system which is small attempt to compete with the today’s digital world.
1.2.2 PROPOSED SYSTEM:
The main aim of this project to provide secure banking system, by
taking fingerprints as authorized identity at banks.
In this ever growing field of electronics everything which is
manufactured is too compact and easy to handle and to understand. The
world is moving towards the automation, day by day as technology is
improving new systems are introduced. Bank locker system is one of the
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way of giving something new to world of traveling. Bank lockers are
used to keep the money, jwellery, important documents etc.
Bank locker security is most important for the safety of the
valuables. There are many cases of bank robbery from the bank lockers. .
In today life bank ATM centers are also not safe enough as there has been
some cases of money robbery from these ATMS. Taking this in account
we have provided a bank locker system which provides safe and user
friendly operation.
The purpose of the project is to provide a secured and reliable
environment to the customers for their banking transactions by providing
a unique identity to every user using the FINGER PRINT identification
technology. Here in this project we are going provide the at most security
since it is taking the FINGER PRINTS as the authentication for our
account. So whenever we want to access our account first we have to
press the finger on the finger print scanner. Scanner is interfaced to the
micro controller with the serial interfacing. The micro controller reads the
data from the scanner. The micro controller allows those users, who are
authorized to operate the account. If any unauthorized user tries to
operate the account the micro controller switches on the security alarm.
The total information about the account holders is stored in the
EEPROM.
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CHAPTER 2
2.1 BLOCK DIAGRAM
Fig 2.1 Block Diagram of Secure BankLocker system
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2.2 BLOCK DIAGRAM DESCRIPTION
The block diagram of the project is as shown above. It consists of
following materials involved as listed below,
In the given block diagram the finger print scanner is connected to a bank
computer which contains the user database including their corresponding
fingerprints.
There are a number of components used in this system that are interfaced
using a PIC microcontroller.
A pc interfacing circuit is provided to interface the user database and the
microcontroller.
In this system we use applications such as a fingerprint scanner and a
gsm modem, and they are connected together using a data multiplexer.
The entire system is controlled by the microcontroller. It is connected
with an LCD screen present in the locker and the electronic lock drives
provided for security.
An alarm is connected with the microcontroller that may be activated
whenever there is a fault access to the locker.
Whenever there is a correct entry of data the microcontroller directs the
electronic locker to open else the alarm will be activated.
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2.3 CIRCUIT DIAGRAM :
Fig 2.2 Circuit Diagram of System
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CHAPTER 3
TOOLS USED
3.1 SOFTWARE TOOLS
3.1.1 MPLAB IDE
IDE-INTEGRATED DEVELOPMENT ENVIRONMENT
IDE is a software application that provides comprehensive facilities to
computer programmers for software development. An IDE normally
consists of Source Code Editor,Compiler and Debugger.
A soure code editor is a text editor program designed specifically
forediting source code of computer programs by programmers.
A compiler is a computer program that transforms source code written in
a programming language into another computer language. The most
common reason for wanting to transform source code is to create an
executable program.
A special program used to find errors in other programs. A debugger
allows a programmer to stop a program at any point and examine and
change the values of variables.
MPLAB IDE is a free,integrated toolset for the development of
embedded applications employing microchip’s PIC and dsPIC
microcontrollers.
MPLAB IDE runs as 32-bit application on MS Windows.
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MPLAB is easy to use and includes a host of free software components
for fast application development and super-charged debugging.
MPLAB IDE also serves as a single,unified fraphical user interface for
additional Microchip and third party software and hardware development
tools.
MPLAB IDE is a integrated toolset for the development of embedded
applications employing Microchip’s PIC microcontrollers.
The MPLAB IDE runs as a 32-bit application on Microsoft windows.
Both assembly and C programming languages can be used with MPLAB
IDE.
3.1.2 ORCAD DESIGN
ORCAD really consists of tools
There are two types of tools.
Capture
Layout
Capture is used for design entry in schematic form.
Layout is a tool for designing the physical layout of components and
circuits on PCB
ORCAD is a proprietary software tool suite used primarily for electronic
design automation.
This software is used mainly to create electronic prints for manufacturing
of printed circuit boards.
It is also used by electronic design engineers and electronic technicians to
manufacture electronic schematics and diagrams and for their simulation.
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During the design process, you will move back and forth between these
two tools.
3.2 HARDWARE TOOLS
GSM Module
Data Multiplexer
Electronic Lock Drive and Lock
Microcontrollers – PIC
Alarm
LCD
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CHAPTER 4
POWER SUPPLY
4.1 INTRODUCTION:
Power supply is a device that transfers electric power from a
source to a load using electronic circuits. typical application of the power
supplies is to convert utility’s AC input power to regulated voltage
required for electronic equipments.
4.2 BASIC FUNCTIONAL UNITS:
Most electronic circuits need a DC supply such as a battery to
power them. Since the mains supply is AC it has to be converted to DC to
be useful electronics. This is what a power supply does.
Fig 4.1 Power Supply Unit
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First the AC mains supply passes through an isolating switch and
safety fuse before it enters the power supply unit.
In most cases the high voltage mains supply is too high for the
electronic circuitry. It is therefore stepped down to a lower value by
means of a Transformer. The mains voltage can be stepped up where
high DC voltages are required. From the transformer the AC voltage is
fed to a rectifier circuit consisting of one or more diodes.
The rectifier converts AC voltage to DC voltage. This DC is not
steady as from a battery. It is pulsating. The pulsations are smoothed out
by passing them through a smoothing circuit called a filter. In its simplest
form the filter is a capacitor and resistor.
Any remaining small variations can, if necessary, be removed by a
regulator circuit which gives out a very steady voltage.This regulator
also removes any variations in the DC voltage output caused by the AC
mains voltage changing in value. Regulators are available in the
form of Integrated Circuits with only three connections.
Each of the blocks is described in more detail below:
Transformer - steps down high voltage AC mains to low voltage
AC.
Rectifier - converts AC to DC, but the DC output is varying.
Smoothing - smooths the DC from varying greatly to a small
ripple.
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Regulator - eliminates ripple by setting DC output to a fixed
voltage.
4.3 WORKING PRINCIPLE:
Fig 4.2 Circuit Diagram of Power Supply
The first section is the TRANSFORMER. The transformer
steps up or steps down the input line voltage and isolates the power
supply from the power line. The RECTIFIER section converts the
alternating current input signal to a pulsating direct current. And the
pulsating dc is not desirable. For this reason a FILTER section is used to
convert pulsating dc to a purer, more desirable form of dc voltage. The
final section, the REGULATOR, does just what the name implies. It
maintains the output of the power supply at a constant level in spite of
large changes in load current or input line voltages.
4.4 TRANSFORMER:
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A TRANSFORMER is a device that transfers electrical
energy from one circuit to another by electromagnetic induction
(transformer action). The electrical energy is always transferred without a
change in frequency, but may involve changes in magnitudes of voltage
and current. Because a transformer works on the principle of
electromagnetic induction, it must be used with an input source voltage
that varies in amplitude. There are many types of power that fit this
description; for ease of explanation and understanding, transformer
action will be explained using an ac voltage as the input source.The
centertap transformer is used in the power supply unit. a center-tapped
transformer and two diodes can form a full-wave rectifier that allows
both half-cycles of the AC waveform to contribute to the direct current,
making it smoother than a half-wave rectifier.a center tap is a wire that is
connected to a point half way along one of the windings of a
transformer , inductor or a resistor.
Center taps are sometimes used on inductors for the
coupling of signals, although most tappings are not at the centre but
usually near one end. In the case of resistors, tapping is usually done only
with potentiometers, and center tapping is just a special case of normal
operation of these devices.
4.5 RECTIFIER:
Rectification is the conversion of alternating current (AC) to
direct current (DC). This almost always involves the use of some device
that only allows one-way flow of electrons. As we have seen, this is
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exactly what a semiconductor diode does. The simplest type of rectifier
circuit is the half-wave rectifier, so called because it only allows one half
of an AC waveform to pass through to the load.
4.6 HALF WAVE RECTIFICATION:
A half wave rectifier is a special case of a clipper. In half wave
rectification, either the positive or negative half of the AC wave is passed
easily while the other half is blocked, depending on the polarity of the
rectifier. Because only one half of the input waveform reaches the output,
it is very inefficient if used for power transfer. Half wave rectification
can be achieved with a single diode in a one phase supply.
Fig 4.3 Half Wave Rectifier
For most power applications, half-wave rectification is
insufficient for the task. The harmonic content of the rectifier's output
waveform is very large and consequently difficult to filter. Furthermore,
AC power source only works to supply power to the load once every
half-cycle, meaning that much of its capacity is unused. Half-wave
rectification is, however, a very simple way to reduce power to a resistive
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load. Some two-position lamp dimmer switches apply full AC power to
the lamp filament for "full" brightness and then half-wave rectify it for a
lesser light output.
4.7 FULL WAVE RECTIFICATION:
IN4001 is the diode that is used to construct rectifier.If we
need to rectify AC power so as to obtain the full use of both half-cycles
of the sine wave, a different rectifier circuit configuration must be used.
Such a circuit is called a full-wave rectifier. One type of full-wave
rectifier, called the center-tap design, uses a transformer with a center-
tapped secondary winding and two diodes, like this:
Fig 4.4 Full Wave Rectifier Circuit(Center-tap)
This circuit's operation is easily understood one half-cycle at a
time. Consider the first half-cycle, when the source voltage polarity is
positive (+) on top and negative (-) on bottom. At this time, only the top
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diode is conducting; the bottom diode is blocking current, and the load
"sees" the first half of the sine wave, positive on top and negative on
bottom. Only the top half of the transformer's secondary winding carries
current during this half-cycle:
Fig 4.5 Full Wave Rectifier Circuit First half Cycle
During the next half-cycle, the AC polarity reverses. Now, the
other diode and the other half of the transformer's secondary winding
carry current while the portions of the circuit formerly carrying current
during the last half-cycle sit idle. The load still "sees" half of a sine wave,
of the same polarity as before: positive on top and negative on bottom:
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Fig 4.6 Full Wave Rectifier Circuit Second half Cycle
One disadvantage of this full-wave rectifier design is the necessity
of a transformer with a center-tapped secondary winding. If the circuit in
question is one of high power, the size and expense of a suitable
transformer is significant. Consequently, the center-tap rectifier design is
seen only in low-power applications.
Another, more popular full-wave rectifier design exists, and it is
built around a four-diode bridge configuration. For obvious reasons, this
design is called a full-wave bridge:
Fig 4.7 Full Wave Rectifier Circuit (Bridge)
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Current directions in the full-wave bridge rectifier circuit are as
follows for each half-cycle.Here we do not use the full wave bridge
rectifier circuit.
4.8 FILTER:
This DC is not steady from a rectifier. It is pulsating. The
pulsations are smoothed out by passing them through a smoothing circuit
called filter. In its simplest form the filter is a capacitor and resistor.
4.9 CAPACITOR FILTER
The simple capacitor filter is the most basic type of power supply
filter. The use of this filter is very limited. It is sometimes used on
extremely high-voltage, low-current power supplies for cathode-ray and
similar electron tubes that require very little load current from the supply.
This filter is also used in circuits where the power-supply ripple
frequency is not critical and can be relatively high. The simple capacitor
filter consists of a single-filter element. This capacitor (C1) is connected
across the output of the rectifier in parallel with the load. The RC charge
time of the filter capacitor (C1) must be short and the RC discharge time
must be long to eliminate ripple action when using this filter. In other
words, the capacitor must charge up fast with preferably no discharge at
all. Better filtering also results when the frequency is high; therefore, the
full-wave rectifier output is easier to filter than the half-wave rectifier
because of its higher frequency.
4.10 78L05 REGULATOR:
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78L05 is the regulator used for the regulation of the DC output
from the filter.The LM78LXX series of three terminal positive regulators
is available with several fixed output voltages making them useful in a
wide range of applications. When used as a zener diode/resistor
combination replacement, the LM78LXX usually results in an effective
output impedance improvement of two orders of magnitude, and lower
quiescent current. These regulators can provide local on card regulation,
eliminating the distribution problems associated with single point
regulation. The voltages available allow the LM78LXX to be used in
logic systems, instrumentation, HiFi, and other solid state electronic
equipment.
The LM78LXX is available in the plastic TO-92 (Z) package, the
plastic SO-8 (M) package and a chip sized package (8-Bump micro
SMD) using National's micro SMD package technology. With adequate
heat sinking the regulator can deliver 100mA output current. Current
limiting is included to limit the peak output current to a safe value. Safe
area protection for the output transistors is provided to limit internal
power dissipation. If internal power dissipation becomes too high for the
heat sinking provided, the thermal shutdown circuit takes over preventing
the IC from overheating.
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CHAPTER 5
PIC MICROCONTROLLER
5.1 INTRODUCTION TO PIC MICROCONTROLLERS
The term PIC, or Peripheral Interface Controller, is the name given
by Microchip Technologies to its single – chip microcontrollers. These
devices have been phenomenally successful in the market for many
reasons, the most significant ones are mentioned below. PIC micros have
grown in steadily in popularity over the last decade, ever since their
inception into the market in the early 1990s. PIC micros have grown to
become the most widely used microcontrollers in the 8- bit
microcontroller segment.
The PIC16F877 is 40 pin IC. There are six ports in this
microcontroller. Namely PORT A, PORT B, PORT C, PORT D and
PORT E. Among these ports PORT B, PORT C and PORT D contains 8-
pins, where PORTA contains 6-pins and PORT E contains 3-pins.
Each pins in the ports can be used as either input or output pins.
Before using the port pins as input or output, directions should be given
in TRIS register. For example setting all the bits in TRIS D register
indicates all the pins in PORT D are used input pins.
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Clearing all the bits in TRIS D register indicates all the pins in
PORT D are used as output pins. Likewise TRIS A, TRIS B, TRIS C,
TRIS E registers available for PORT A, PORT B, PORT C and PORT E.
The main factors that account for the popularity of PIC micros
include the following:
Speed: When operated at its maximum clock rate, a PIC executes
most instructions in 0.2µs, or five instructions in a microsecond.
Instruction set simplicity: The instruction set consists of just 35
instructions.
Integration of operational features: PIC micros have features
like Power on Reset and Brown out protection which ensures that the
chip operates only when the supply voltage is within specification. A
watchdog timer resets the PIC if the chip ever malfunctions and deviates
from its normal operations.
Flexibility in clock sources: The PIC micros can be run with four
different types of clock sources which help in cost cutting and power
saving.
High current capabilities of ports: The ports pins on PIC micros
can source and sink up to 25mA, which make them all the more versatile
and economic.
Serial programming via two pins: PIC micros can be
programmed serially with two pins, which bring down the complexity
and the cost of PIC programmers, drastically.
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On chip EEPROM: The on chip EEPROM helps retain critical
data even if the power is down. There by reducing the cost of and
external EEPROM from the overall system cost.
5.2 MICROCONTROLLER ARCHITECTURE
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Fig 5.1 Microcontroller Architecture
5.3 GENERAL DESCRIPTION OF P16F877
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The architecture of PIC16F877 contains 4-banks of register
files such as Bank 0, Bank 1, Bank 2 and Bank 3 from 00h-07h, 80h-FFh,
100h-17Fh and 180h-1FFh respectively. And it is also having program
FLASH memory, Data memory and Data EEPROM of 8K, 368 and 256
Bytes respectively.
5.4 REGISTER FILE
The term register file in PIC terminology used to denote the
locations than an instruction can access via an address. The register file
consists of two components, they are
General purpose register file
Special purpose register file
5.4.1 GENERAL PURPOSE REGISTER FILE
The general-purpose register file is another name for the
microcontrollers RAM. Data can be written to each 8-bit location,
updated and retrieved any number of times. All control registers are
coming under the general purpose register file.
5.4.2 SPECIAL PURPOSE REGISTER FILE
The special purpose register file contains input and output ports as
well as the control registers used to establish each bit of port as either an
input or output. It contains registers that provide the data input and data
output to the variety of resources on the chip, such as the timers, the
serial ports and the analog–to–digital converter. It has registers that
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contain control bits for selecting the mode of operation of a chip resource
as well as enabling or disabling its operation.Every instruction that can
employ the direct addressing mode can, as an alternative employ the
indirect addressing mode. In this alternative mode, the full 8-bit register
file address is first written into FSR, a special purpose register that serves
as an address pointer to any address throughout the entire register file.
5.5 MINIMUMBASICCIRCUIT EXPLANATION FOR
PIC16F877A
Fig 5.2 Circuit Diagram for PIC 16F877A
The Minimum basic circuit is the fundamental circuit that is
required for the microcontroller to run. The above shown circuit is one of
the possible minimum basic circuits for the PIC. Like most other
microcontrollers, for the PIC to execute any application the following are
required
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The Power Input
The Clock input
The Reset circuit
5.5.1 THE POWER INPUT :
The microcontroller works on 5V DC and it can be given either to
Pin 32 or Pin 11. Both these pins are Vdd inputs or power inputs. The Vss
signal on the microcontroller must be connected to the ground these are
Pins 10 or Pin 31.
Between the 5V and the ground a 0.1uF capacitor is connected.
This capacitor is used to eliminate any noise in the 5V input to the
microcontroller. This capacitor is called a Decoupling capacitor.
5.5.2 THE CLOCK CIRCUIT :
Any microcontroller or processor needs a clock source for it to
execute a program. There are various ways of giving the clock signal to a
microcontroller, the most reliable and the common method used is to use
a crystal oscillator. Between the Pin number 13 and 14 a crystal oscillator
is connected. When the power is given to the microcontroller, the crystal
oscillator starts producing clock signals at a frequency of 20MHz.
A 20MHz crystal is used because it is the highest frequency at
which the PIC can work and hence it gives the fastest program execution
speed at this frequency. If required, lesser frequencies can also be used.
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For changing the frequency a different crystal of a different resonant
frequency must be used.
To the crystal two ceramic capacitors are connected each of 33pF
value. These two capacitors are called loading capacitors and are required
for the crystal to produce a continuous and uniform clock signal. The
values of these capacitors are specified by the manufacturer of the crystal
and the microcontroller.
5.5.3 THE RESET CIRCUIT :
Pin 1 on the PIC is the RESET signal input. The RESET signal is
an active low signal. When a low voltage (0V) is applied to the pin 1, the
microcontroller gets reset. For the normal execution of the project the pin
1 must be maintained at a high voltage (5V).
For providing the RESET signal a resistor and a switch are
connected to pin1. The resistor is connected to 5V and this will normally
maintain the pin 1 at 5V and the microcontroller will function normally.
When the switch is pressed pin 1 is connected to ground and the voltage
at pin 1 becomes 0V. Under this condition the microcontroller gets reset.
Thus pressing the switch will reset the microcontroller.
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5.5 PIN DIAGRAM
Fig 5.3 Pin Diagram
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5.6 EXPLANATION FOR PIC16F877A :
To operate a microcontroller, you need some basic components to
support it and the circuit we call it basic circuit. above, i will share the
schematic of basic circuit to operate a PIC16F877A microcontroller.
IN4148 - is a Shockley diode to allow the microcontroller to be
programmed by ICSP method
SW - is a 2 pins push button to allow manually reset the microcontroller
R1k - is a 1K 1/4 W resistor to pull high or enable the MCLR pin
XTAL - is a crystal oscillator to generate clock to the microcontroller
C - supporting parts for the crystal
VCC - 5V supply
GND - 0V
5.7 FEATURES:
High-performance RISC CPU
All single cycle instructions except for program branches which are 2 cycle
Operating speed: DC - 20 MHz clock input DC - 200 ns instruction cycle
Up to 8K x 14 words of Flash Program Memory,
Up to 256 x 8 bytes of EEPROM data memory
Pin out compatible to the PIC16C73/74/76/77
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Interrupt capability -up to 14 internal/external
Eight level deep hardware stack
Direct, indirect, and relative addressing modes
Power-on Reset (POR)
Power-up Timer (PWRT) and Oscillator Start-up Timer (OST)
Watchdog Timer (WDT) with its own on-chip RC Oscillator for reliable operation
Programmable code-protection
Power saving SLEEP mode
Selectable oscillator options
Low-power, high-speed CMOS EPROM/EEPROM technology
Fully static design
In-Circuit Serial Programming (ICSP) via two pins
Only single 5V source needed for programming capability
In-Circuit Debugging via two pins
Processor read/write access to program memory
Wide operating voltage range: 2.5V to 5.5V
High Sink/Source Current: 25 mA
Commercial and Industrial temperature ranges
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CHAPTER 6
PC INTERFACING
6.1 INTRODUCTION
To interface the project to the computer, the RS232 port on the
computer is used.RS232 is the technical name of the serial port on the
computer, which is also referred to as the comm port (communications
port). Before going into the details of the RS232 lets first evaluate all the
other options available and find out why the RS232 port is used for the
project.
The standard IBM clone PC has a variety of ports or interfaces
available for different applications. Some of these ports like the VGA
port, the Ethernet port and the PS2 port are for dedicated purposes. But
the rest of the interfaces are quite general and can be used for interfacing
custom hardware and applications like experimental projects. These are
the ports like,
1. The Universal Serial Bus Port or the USB port
2. The Parallel port.
3. The Serial port or the Common port
6.1.1 THE USB PORT :
The Universal serial Bus Port or in short the USB port is
undoubtedly the most popular general purpose port that is available on
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the computer. Also any relatively modern computer has normally four
and some times even six USB ports. Hence the chances of finding a free
USB port for interfacing are always quite high. The USB is a very good
option when high speed communication is required. But the USB is not
always a very good option for experimental interfacing like in the case of
a project.
USB in spite all its advantages is a relatively complicated port to
use in terms of programming. Also most software like Visual Basic or
even technical software likes Lab View; don’t have features to use the
USB port directly. Hence if a user wants to interface a custom hardware
to a USB port he has to write device drivers which require a in depth and
a detailed knowledge of the operating system. Also for interfacing a
application to the USB port, the application hardware must have a USB
controller IC, or a microcontroller which supports USB communication.
Hence using a USB port is both complicated on the hardware and the
software front.
6.1.2 THE PARALLER PORT:
The parallel port on the computer was actually developed for
communication with line printers. Until a few years back printers still
used the parallel port. But now with the USB port becoming the preferred
choice for all peripheral communications, the parallel port is not used any
more. But to maintain compatibility with older computers, recent
computers still have the parallel port. Generally computers have always
had only one parallel port and even today a single parallel port is present
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on all computers. Since printers generally use the USB port, the parallel
port is most often available free for being used as a general purpose port.
The parallel port is a simple port to use in terms of hardware
requirements for interfacing to the port. But the only and the main draw
back to using the parallel port lies in the concept of parallel
communication. For doing 8 bit data transfer over a parallel port 8 wires
are used and also 8 pins on a microcontroller would be used up. Using up
8 pins on a microcontroller just for communication is not a very efficient
usage of the microcontroller. Also since 8 wires are used for the
communication, the cable becomes bulky. Another major disadvantage of
the parallel port is the limitation on the distance of communication.
Depending upon the speed of the communication the distance of
communication for the parallel port is about a few feats only. Hence the
parallel port is also not the best choice when it comes to general purpose
interfacing.
6.1.3 THE SERIAL PORT :
The serial port or the comm port (short form for communication
port) is another available option for interfacing to the PC. The serial port
on computers is in accordance with the RS232 standard defined by the
EIA/TIA (Electronic Industry Association and the Telecommunications
Industry Association) and hence is also referred to as the RS232 port (RS
means Recommended Standard).
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The RS232 port was developed in the 1970’s for connecting
devices like modems to a computer. Later on they were used for many
other functions like connecting mouse, keyboards and even printers to a
computer. But with the USB gaining in popularity the serial port is very
rarely used these days. Hence the RS232 port like the parallel port is
almost always free.
But unlike the parallel port the RS232 port is much easier to use
for general purpose interfacing and experimentation. On the
programming front the serial port is the easiest of all the ports on a
computer to use. Serial port can be directly accesses from most high level
languages directly with simple commands. Also most microcontrollers
come with a inbuilt serial communication module (USART) and hence
programming the PC and a microcontroller for serial communication is
very easy.
Also since the communication is serial the number of wires
required for data transfer is also minimal. Mostly just three wires are
sufficient for doing full duplex serial communication. Hence the cabling
is also simple and the number of pins used up on the microcontroller is
also minimal. Also the RS232 is capable of communicating over much
more longer distances than the parallel port.
The RS232 standard defines two types of connectors that can be
used for communication.
35
Fig 6.1 RS-232 Connector Pin Assignment
The two types of connectors are shown above. Among the two the
25 pin connectors has become obsolete and is not used any more. All
computers these days have the 9 pin connector. Even on the 9 pin
connectors most signals are not used these days as they were primarily
designed for communication with a modem. In fact for simple
experimental purposes only three of the 9 pins are used. These are pins 2,
3 and 5. Pin 2 is for receiving data, pin 3 is transmitting data and pin 5 is
ground. With these three pins most communications can be
accomplished.
36
The only drawback to RS232 port is the fact that it works at
different voltage levels than conventional TTL/CMOS devices like
microcontrollers. Because of this a voltage conversion device or circuit is
required between the PC and the microcontroller.
6.2 RS232 VOLTAGE LEVELS
As mentioned earlier RS232 uses voltage levels which are very
different from TTL/CMOS circuits or devices. The reason being the fact
that RS232 was defined in 1962 and at that time TTL/CMOS circuits
were not widely used. Also RS232 was created to handle relatively long
distances and hence used much higher voltages than any other digital
circuits. In the RS232 standard, a logic “HIGH” or logic 1 is represented
by a -5V to -15V signal and a logic “LOW” or a logic 0 is represented by
a +5V to +15V signal during transmission.
During reception, a logic HIGH or a logic 1 is represented by a -
3V to -15V signal and a logic LOW or logic 0 is represented by a +3V to
+15V signal.
These Voltages are a stark contrast to the voltages used by most
TTL/CMOS circuits where a logic HIGH or logic 1 is generally
represented by a +5V signal and a logic LOW or logic 0 is represented by
a 0V signal.
37
Fig 6.2 RS-232 Voltage Level
6.3 RS232 VOLTAGE LEVEL CONVERTERS:
As mentioned earlier the microcontroller uses TTL/CMOS signals
and hence by connecting the microcontroller directly to the RS232 port
the communication is not possible as both use different voltage levels.
Hence there is a need to use a circuit or a device which can convert the
TTL/CMOS signals to RS232 signals and vice versa.
This voltage level conversion can be done either using discrete
components or using ICs which are specifically built for the purpose of
RS232 voltage level conversions. There a quite a few ICs available for
38
0V
+5V
-5V
+15V
-15V
Logic 0
Logic 1
0V
+3V
-3V
+15V
-15V
Logic 0
Logic 1
Transmission Reception
this purpose, one such IC is MAX232. The MAX 232 is a very popular
IC and it is in a way the default choice for RS232 voltage conversions.
The MAX 232 is automatically converts TTL/CMOS input to RS232
signals and vice versa.
Fig 6.3 Pin Diagram of MAX232
39
Fig 6.4 Circuit Diagram
The MAX232 is a 16 pin IC and it requires external 5 capacitors to
do the voltage conversions. MAX232 uses a 5V power input and from the
5 volts it generates +10V and -10V, which are used for the RS232
communication as they are within the RS232 voltage levels.
There are two buffers for converting from RS232 to TTL/CMOS
and two for conversion for TTL/CMOS to RS232. Pin number 11, 12 are
TTL/CMOS inputs and the corresponding RS232 signals can be taken out
from pins 14 and 7. Similarly pins 13, 8 are RS232 inputs and the
corresponding TTL/CMOS out puts can be taken on pins 12 and 9.
40
CHAPTER 7
DATA MULTIPLEXER
7.1 INTRODUTION
A multiplexer (or MUX) is a device that selects one of several
analog or digital input signals and forwards the selected input into a
single line. A multiplexer of 2n inputs has n select lines, which are used
to select which input line to send to the output. Multiplexers are mainly
used to increase the amount of data that can be sent over the network
within a certain amount of time and bandwidth. A multiplexer is also
called a data selector.
7.2 GENERAL DESCRIPTION
These data selectors/multiplexers contain inverters and drivers to
supply full on-chip data selection to the four output gates.
Fig 7.1 Order Number 54157DMQB(Multiplexer)
41
A separate strobe input is provided. A 4-bit word is selected from
one of two sources and is routed to the four outputs.
INPUTOUTPUTStrobe Select A B
HLLLL
XLLHH
XLHXX
XXXLH
LLHLH
Table 7.1 Function Table
7.3 ABSOLUTE MAXIMUM RATINGS
If Military/Aerospace specified devices are required,please contact the
National Semiconductor Sales Office/Distributors for availability and
specifications.
Supply Voltage = 7V , Input Voltage = 5.5V
Operating Free Air Temperature Range
DM54 and 54 b55§C to a125§C
DM74 0§C to a70§C
Storage Temperature Range b65§C to a150§C
42
7.4 LOGIC DIAGRAM
Fig 7.2 Logic Diagram
7.5 FEATURES
Buffered inputs and outputs .
Typical propagation time 9 Ns.
Typical power dissipation 150 mW.
Alternate Military/Aerospace device (54157) is available. Contact a
National Semiconductor Sales Office/Distributor for specifications.
7.6 APPLICATIONS
Expand any data input point.
Multiplex dual data buses.
Generate four functions of two variables (one variable is common).
43
CHAPTER 8
GSM MODEM
8.1 DEFINITION
Gobal system for mobile communication (GSM) is a globally
accepted standard for digital cellular communication. GSM is the name
of a standardization group established in 1982 to create a common
European mobile telephone standard that would formulate specifications
for a pan-European mobile cellular radio system operating at 900MHz.
8.2 THE GSM NETWORK
GSM provides recommendations, not requirements. The GSM
specifications define the functions and interface requirements in detail
but do not address the hardware.
Fig 8.1 GSM Network
44
The reason for this is limit the designers as little as possible but
still to make it possible for the operators to buy equipment from different
suppliers. The GSM network is divided into three major systems : the
switching system(SS), the base station system(BSS),and the operation
and support system (OSS).
8.3 FACTS OF GSM MODEM:
The GSM/GPRS Modem comes with a serial interface through
which the modem can be controlled using AT command interface. An
antenna and a power adapter are provided.
AT commands are ATtention commands used for various operation with a
modem like a GSM modem.
Ex:
ATD <number> - is used for dialing to a certain number.
Similarly there are AT commands used for all the different operations
possible with a modem.
There are standard and extended AT commands.
Standard AT commands are mainly used for telephone and FAX related
applications.
Extended AT commands are used with GSM modems for SMS and data
related communications.
For sending sms AT+CMGS is used.
45
The basic segregation of working of the modem is as under:
• Voice calls
• SMS
• GSM Data calls
• GPRS
Voice calls:
Voice calls are not an application area to be targeted. In future if
interfaces like a microphone and speaker are provided for some
applications then this can be considered.
SMS:
SMS is an area where the modem can be used to provide features
like:
• Pre-stored SMS transmission, these SMS can be transmitted on certain
trigger events in an automation system.
• SMS can also be used in areas where small text information has to be
sent. The transmitter can be an automation system or machines like
vending machines, collection machines or applications like positioning
46
systems where the navigator keeps on sending SMS at particular time
intervals
• SMS can be a solution where GSM data call or GPRS services are not
available
GSM Data Calls:
Data calls can be made using this modem. Data calls can be made
to a normal PSTN modem/phone line also (even received). Data calls are
basically made to send/receive data streams between two units either
PC’s or embedded devices. The advantage of Data calls over SMS is that
both parties are capable of sending/receiving data through their terminals.
Some points to be remembered in case of data calls:
• The data call service doesn’t come with a normal SIM which is
purchased but has to be requested with the service provider (say Airtel).
• Upon activation of data/fax service you are provided with two separate
numbers i.e. the Data call number and the Fax service number.
• Data calls are established using Circuit Switched data connections.
• Right now the speed at which data can be transmitted is 9.6 kbps.
• The modem supports speeds up to 14.4 kbps but the provider give a
maximum data rate of 9.6 kbps during GSM data call.
47
• Technologies like HSCSD (high Speed Circuit Switched Data) will
improve drastically the data rates, but still in pipeline..
CHAPTER 9
FINGER PRINT SCANNER
9.1 FINGER PRINT SCANNER
The fingerprint recognition system may suffer attacks at different
points during the authentication process. The following figure shows the
possible points. In each of these point the data may be altered and forced
an authentication of unregistered user.
Fig 9.1 Block Diagram of Finger Print Technique
48
The most common attacks occur by the use of fake fingerprint during the
capture of image. A fake fingerprint are build from latent fingerprint left
at touched items such as glasses, doorknobs, glossy paper, etc. Using this
fingerprint are build three-dimensional molds of rubber membrane, glue,
or gelatin.
During the transmission of the image to the feature extractor may occur
interception of the channel, and consequently, the fingerprint image may
be stolen and later, used for fake fingerprint construction or for directly
access to feature extractor by bypassing the scanner.
The feature extractor may be substitute by a Trojan horse, which bypass
the feature extractor and generate artificial template and submit to the
matcher.
The transmission channel between the feature extractor and matching
may also be intercepted and the fingerprint feature may be stored for the
later use.
In the matching module may occur the same problem as in the feature
extractor. The presence of Trojan horse may produce always the desired
result independent of the input fingerprint.
The database may also suffer attack of Trojan horse, by which can be
created artificial record and submit to the matching module.
The record of legitimate user may be stolen by intercepting the
communication channel between the database and matching.
49
Finally, the channel between the matching module and the application
requesting verification is also susceptible for possible attacks.
All these attacks are similar to those presented in token and
knowledge based authentication (password) system, except the case of
attack using fake fingerprints which is particular of fingerprint
recognition system. In this subsection are presented some
recommendation to countermeasure the possible attacks, in especial the
attacks by the use of fake fingerprint.
Independently how the fingerprint was stolen, the fingerprint
scanners should be able to reject the fake fingerprints. However detecting
the aliveness of a finger it is not an easy task.
The main problem relies on how to differentiate a live finger from
that one made of some synthetic material. There has been proposed some
ideas to deal with this problem, which consist in using the thermal,
electric and optical properties of the material presented to the fingerprint
scanner. By using the temperature information, for example, it is
expected that the fake finger made of silicone rubber is about 2 degree
cooler than a live finger, however, due the temperature variation of the
environment and the possibility of artificial heating the fake finger, the
thermal measurements are not very reliable.
The conductivity is another measure that could be explored,
however, the conductivity of a live finger varies a lot depending of
weather condition such as humidity and temperature. The optical
properties such absorption, reflection, scattering and refraction, in the
50
human skin are different than many other synthetic material. However, it
is not difficult to find materials that have optical properties close to those
of a live finger.
As we can see, there no exists a reliable characteristic that could reject
all fake fingerprints. Therefore, it is important to take special attention
during the design and development of a secure fingerprint system. Here
are listed some considerations in order to improve the security.
Enroll and use multiple finger for single authentication
Change occasionally the patterns by using multiple fingerprint
Use device that detect better the aliveness of the finger
For more secure system, include password verification
Occasionally re-enroll the fingerprint
Allow identification to occur only from a certain fingerprint scanner
Reduce the sensitivity to reduce the possibility of false positive
Control the physical access to fingerprint scanner where possible
Make regular maintenance of devices for heavy usage environments
9.2 FINGERPRINT SEGMENTATION
51
Before extracting the feature of a fingerprint, it is important to
separate the fingerprint regions (presence of ridges) from the background.
This limits the region to be processed and therefore reduces the
processing time and false feature extraction. A correct segmentation may
be, in some cases, very difficult, especially in poor quality fingerprint
image or noisy images, such as presence of latents. The same information
used for quality extraction, such as contrast, ridge orientation and ridge
frequency can be used for the segmentation or inclusive the quantified
region quality may be used directly by considering as background the
regions with quality below some threshold. Normally, the segmentation
are also computed by block in the same way as the quality extraction. In
the above figure is shown the contour of the segmented region
superimposed over the original image.
original image image with segmentation
Fig 9.2 Finger Print Segmentation
52
9.3 STRENGTHENS AND WEAKNESS
The fingerprint recognition technique is the dominant technology in
the biometric market. There many factors that contribute for this success.
High level of accuracy. It is proven that the fingerprint recognition
technology may reach recognition rate near 100% in good quality
images.
Easy to use devices, the device used for capturing fingerprint
image are intuitive and easy to use.
Ability to enroll multiple fingers, if there some problem with one
finger, the fingerprint technology still can be used with the other 9
fingers, sometimes using multiple finger improve the recognition.
Range of deployments environments, It can be used in any place
where biometric authentication or identification are needed.
9.4 LIMITATIONS OF THE FINGERPRINT TECHNOLOGY :
Inability to enroll some users. About 2 % of the population have
poor quality of fingerprint, especially the elder people and manual
worker. For these cases one need to consider other biometrics or any
other solution.
Performance deterioration over time. Although the fingerprint is
a stable physiological characteristic, it can suffer some small changes
along the time and therefore it can affect the performance of the whole
53
system. To overcome this problem, may be necessary to re-enroll the
fingerprint and/or use multiple fingerprints enrollment.
Association with forensic application. The fingerprint
technology has been associate with forensic and this can cause
discomfort to some people. Specially, in the countries where it is not
habitual the use of fingerprint.
Need to deploy specialized devices. The device needed for
fingerprint capture is not yet present on desktops, at sales point, etc, as is
the case of microphones and telephones used in voice recognition. The
integration of fingerprint scanner within the keyboard will reduce this
weakness.
CHAPTER 10
LIQUID CRYSTAL DISPLAY
10.1 INTRODUCTION
Liquid Crystal Displays (LCDs) have materials, which combine
the properties of both Liquids and Crystals. Rather than having a melting
point, they have a temperature range with in which the molecules are
almost as mobile as they would be in a Liquid, but are grouped together
in an ordered form similar to a crystal.
54
The LCDs used exclusively in watches, calculators and measuring
instruments are the simple seven-segment displays, having a limited
amount of numeric data. The recent advances in technology have resulted
in better legibility, more information displaying capability and a wider
temperature range. These have resulted in the LCDs being extensively
used in telecommunications and entertainment electronics. The LCDs
have even started replacing the Cathode Ray Tubes (CRTs) used for the
display of text and graphics, and also in small TV applications.
10.2 ELECTRO-OPTICAL CHARACTERISTICS OF THE LCD’s:
The Electro-optical characteristic of the LCD depends on the type
of Liquid Crystal material used. The widely used types are the Twisted
Nematic (TN) and the super Twisted Nematic (STN) types. The
legibility/readability of an LCD depends on a variety of factors such as
the type of display, driving and illumination conditions, viewing angle
and the operating temperature. The important optical characteristics by
which legibility is expressed are: brightness, contrast ratio and viewing
angle.
10.3 BRIGHTNESS:
Brightness of an LCD is the ratio of the luminance of the incident
light. Reflective displays will therefore tend to appear rather grey/dark. A
brighter display can be obtained by providing backlighting.
10.4 CONTRAST RATIO:
55
Contrast ratio of an LCD is defined as the ratio of brightness of the
lighted/non-activated pixels to that of the darkened/activated pixels.
Brightness of non-activated pixels (B2)
Contrast Ratio = ------------------------------------------------
Brightness of activated pixels (B1)
Brightness and contrast, both depends on the polarisers used. Low
efficiency polarisers give bright displays but a low contrast. High
efficiency polarisers give a high contrast but reduce the brightness.
10.5 VIEWING ANGLE AND DIRECTION :
The viewing angle can be defined as the cone subtended by the
viewer’s eye, when the display is viewed at the two extreme angles while
having a readable contrast level.The viewing direction can be defined as
the viewer’s-eyes direction with respect to the normal drawn
perpendicular to the Display’s surface. When the Display is viewed from
above the normal, it is termed as the top view (12o’clock) and when from
below the normal, it is termed as the bottom view (6o’clock).
A1-Approximate Nominal viewing cone (Top&Bottom view) for TN
type.
B1- Approximate Adjustable viewing cone (Top& Bottom view) for TN
type.
A2- Approximate Nominal viewing cone for STN type.
56
B2- Approximate Adjustable viewing cone for STN type.
The approximate viewing angle for TN type is 40-45 degrees and
for STN type is 75 degrees.
The temperature ranges are as follows:
Particulars NormalTemp.Range Extd.Temp.Range
Operating temperature 0ºC to +50ºC -20ºC to +70ºC
Storage temperature -20ºC to +70ºC -30ºC to +80ºC
TABLE 10.1
10.6 CONNECTING LCDs:
The terminals of the LCD are etched under the edges of the top
glass panel. The LCDs can be electrically connected to the PCB/driver
circuits by using conductive Rubber strips, fixed pins or by foil.
The following features of the conductive rubber strips like:
Simple design with a wide range of sizes, easy assembling, shock
and vibration absorption, absence of corrosion even at 100% humidity,
better conductivity without any abrasion and a longer life, makes them
the widely used connecting materials out of the three types.
The conductive rubber (elastomer) consists of alternate conductive
(carbon filled) and insulating rubber section. Insulating layers of soft
rubber or sponge covers the two sides of this effective contact section.
57
When squeezed between the LCD and the PCB, at least one
conductive section connects between opposite contacts, while at least one
insulating section prevents short circuit with adjacent contacts. For the
proper electrical contact, a bezel or a clamp maintains the contact
pressure. Maintaining the appropriate contact pressure is on the display.
CONCLUSION
This project “multimodal security system for bank locker and
secure locations with GSM alert and remote alarm activation” is used
to secure the bank sectors and other locations such as jewellery shops,
home lockers, etc..,
58
In the existing system only mechanical locks were used, in the
proposed system we are using electronic locks in the place of
mechanical locks, and this is more secure and cost efficient.
APPENDIX
#include <pic.h>
#include <string.h>
59
#include "delay.h"
#include "output.h"
#include "gsm.h"
#define ycard 1
#define forpc (cs0 = 1)
#define forRFID ((cs0 = 0))
extern volatile bit gsmreadyled @ (unsigned)&PORTD*8+5;
static volatile bit yesled @ (unsigned)&PORTD*8+6;
static volatile bit cs0 @ (unsigned)&PORTC*8+1;
void rxdatafrompc(void);
void changetogsm(void);
void changetopc(void);
void txalerttogsm(void);
void alertmsg(void);
unsigned bank1 char mblno[11], code[10];
unsigned const char mblno_police[] = "9003636359";
void main(void)
60
{
usartinit(9600);
gsmreadyled = 1;
msdelay(500);
gsmreadyled = 0;
yesled = 1;
msdelay(500);
yesled = 0;
changetogsm();
msdelay(500);
checkgsmready();
while (1)
{
changetopc();
while(usartrx() != 'S');
if(usartrx() != 'Y')
{
61
relay = 1;
changetogsm();
txalerttogsm();
relay = 0;
}
msdelay(2000);
}
}
void changetogsm(void)
{
forgsm;
RCIE = 1;
msdelay(1000);
}
void changetopc(void)
{
forpc;
62
msdelay(1000);
RCIE = 0;
}
void txalerttogsm(void)
{
gsmreadyled = 0;
RCIE = 0;
do
{
txgsmmblno(mblno_police);
alertmsg();
checkgsmtx();
}while(!gsmokbit);
gsmreadyled = 1;
RCIE = 1;
}
void alertmsg (void)
63
{
usarttxs("UNAUTHORISED CARD USAGE AT ATM No. :
34561233, SBI, N.L.ROAD, CHENNAI");
}
void interrupt intl(void)
{
if (RCIF)
{
if(gsmokstartbit)
{
dummy_gsmreceivedata = RCREG;
}
else
{
gsmreceive_routine();
}
}
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}
}
REFERENCES
PIC Microcontroller Project Book by John Iovine
PIC Basic Projects: 30 Projects using PIC BASIC and PIC
BASIC PRO by Dogan Ibrahim In Stock.
www.microchip.com
65
www.mikroe.com/en/books/picbook/picbook.htm
www.electronics4u.com
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