Krupal Final

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MICROCONTROLLER BASED HEART RATE METER

BACHELOR OF TECHNOLOGY

IN

ELECTRONICS AND COMMUNICATION

ENGINEERING

M.KRUPAL KUMAR (08AG1A0437)

P.HARSHAVARDHAN (08AG1A0451)

N.SHASHIKANTH (08AG1A0439)

DEPARTMENT OF ELECTRONICS AND

COMMUNICATIONS

ACE ENGINEERING COLLEGE

Ankushapur(V), Ghatkesar(M), R.R.Dist - 501 301

2011-12

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MICROCONTROLLER BASED HEART RATE METER

A Mini Project Report

Submitted in the partial Fulfillment of the

Requirements

For the Award of the Degree of

BACHELOR OF TECHNOLOGY

IN

ELECTRONICS AND COMMUNICATION

ENGINEERING

SUBMITTED

BY

M.KRUPAL KUMAR (08AG1A0437)

P.HARSHAVARDHAN (08AG1A0451)

N.SHASHIKANTH (08AG1A0439)

DEPARTMENT OF ELECRTRONICS AND COMMUNICATIONS


Ankushapur(V), Ghatkesar(M), R.R.Dist - 501 301

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Ankushapur[v], Ghatkesar [M], R.R dist-501301

(Approved by AICTE, Newdelhi and affiliated to JNTUH)

CERTIFICATE

This is to certify that the mini project entitled MICROCONTROLLER BASED

HEART RATE METER done by M.Krupalkumar (08AG1A0437), P.Harshavardhan

(08AG1A0451), N.Shashikanth (08AG1A0439) of Department of Electronics and

Communications Engineering, is a record of bonafide work carried out by them. This

mini project is done as a partial fulfillment of obtaining Bachelor of Technology De-

gree to be awarded by Jawaharlal Nehru Technological University, Hyderabad, during

the academic year 2011-12

C.Satyanarayana S.Surya Narayana

Associate Professor, Professor and Head,

Department of ECE Department of ECE

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ACKNOWLEDGEMENT

It is a pleasure to thank the many people who made this project possible.

We would like to express the deepest appreciation to our internal guide ,C.Satyanarayana, Department of Electronics & Communications, Who has the

attitude and the substance of genius . He continually and convincingly conveyed

a spirit of adventure in regard to the project and an excitement in regard to

teaching. Without his guidance and persistent help this project would not have

been possible.

We are indebted to the Head of the Department of Electronics and Com-

munications Engineering, S.Suryanarayana for giving us an opportunity to work

on this project. Being the Socratic force that he has always been brought us clos-

er to the reality we had initially perceived, eventually enabling us to grasp the

rich complexity of the engineering world.

We would like to thank the principal, Dr.V.Buchaiah of ACE engineering

college for the steadfast support throughout of our course of Engineering and for

providing a stimulating and fun environment in which to learn and grow.

We are especially grateful to the faculty members of department of Electron-

ics and Communications for their kind assistance.

We are forever grateful to our parents whose foresight and values paved the

way for a privileged education .

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ABSTRACT

Heart rate can be measured either by the ECG waveform or by the

blood flow into the finger (pulse method). The pulse method is simple and convenient.

When blood flows during the systolic stroke of the heart into the body parts, the finger

gets its blood via the radial artery on the arm. The blood flow into the finger can be

sensed photo-electrically. To count the heart beats, here we use a small light source on

one side of the finger (thumb) and observe the change in light intensity on the other

side. The setup uses a IR transmitter for light illumination of flesh on the thumb behind

the nail and the IR receiver as detector of change in the intensity due to the flow of

blood .The photo-current is converted into voltage and amplified by operational ampli-

fier IC LM358

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INDEX PAGE NO.

CERTIFICATE 3

AKNOWLEDGMENT 4

ABSTRACT 5

1. INTRODUCTION 8

2. GENERAL HEART MONITERING SYSTEM 9

3. DESIGN OF MICROCONTROLLER BASED HEART RATE

METER 10

4. HARDWARE DEVELOPMENT 12

5. HARDWARE REQUIREMENTS 14

6. COMPONENTS DESCRIPTION 16

6.1 LM358 QUAD OPERATIONAL AMPLIFIER 16

6.2 7805, 5V REGULATOR 17

6.3 2 X 16 LIQUID CRYSTAL DISPLAY 18

6.4 CRYSTAL OSCILLATOR 19

6.5 BC548 NPN TRANSISTOR 21

6.6 DIODES 22

6.6.1 1N4007 RECTIFIER DIODE, 6.6.2 LED 23

6.7RESISTORS AND CAPACITORS 24

6.8AT89S52 MICROCONTROLLER 36

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6.9 PROGRAM 30

7. CONCLUSION 37

8. FUTURE SCOPE 38

INDEX PAGE NO.

LIST OF FIGURES

1. FIG.2 GENERAL HEART MONITRING SYSTEM 9

2. FIG.3 DESIGN OF MC BASED HEART RATE METER 10

3. FIG.3.1 BLOCK DIAGRAM 11

4. FIG.4 CIRCUIT DIAGRAM 12

5. FIG.4.1 FINGER CLIP MODELS 13

6. FIG.6.1.1 LM385 QUAD OPAMP 16

7. FIG. 6.1.2 PIN CONFIGURATION OF 7805 17

8. FIG. 6.2.1 7805,5V VOLTAGE REGULATOR 17

9. FIG.6.3.1 LCD 19

10. FIG.6.4.1,6.4.2 CRYSTAL OSCILLATOR 20

11. FIG.6.5.1,6.5.2 BC 547 NPN TRANSISTOR 2112. FIG.6.6.1 RECTIFIER DIODE 23

13. FIG.6.6.2 LED 23

14. FIG.6.7.1 RESISTORS 24

15. FIG.6.7.2 CAPACITOR 25

16. FIG.6.8.1 PIN DIAGRAM OF AT89S52 27

17. FIG.6.8.2 BLOCK DIAGRAM OF AT89S52 28

18. LCD DISPLAY 38

LIST OF TABLES

1. TABLE1 HARDWARE REQUIREMENTS 14-15

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CHAPTER 1

INTRODUCTION

Manya time we measure the heart rate by using the ECG waveform.

This leads to considerable wastage of money Though some circuits are already avail-

able for the purpose, most of them are

1. Expensive,

2. Require a thorough knowledge of microcontroller programming,

3. Too complicated to assemble by amateurs and hobbyists.

Some others are too basic in their operation and prone to malfunction.

This Project MICROCONTROLLER BASED HEART RATE METER is

a reliable circuit that takes over the task of controlling the appliances.

Microcontroller based heart rate meter is presented here the pulse method is simple and

convenient. When blood flows during the systolic stroke of the heart into the body

parts, the finger gets its blood via the radial artery on the arm. The blood flow into the

finger can be sensed photo-electrically.

Microcontroller IC AT89S52 is at the heart of the circuit. It is a 40-pin, 8-bit microcon-

troller with 8 KB of Flash programmable and erasable read-only memory (EPROM).

The design of a low-cost microcontroller based device for measuring the heart pulse

rate has been described. The device has the advantage that it can be used by non-pro-

fessional people at home to measure the heart rate easily and safely.

The circuit presented here is relatively simple, inexpensive and can be assem-

bled by anyone having some knowledge of Electronics.

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Fig.2

CHAPTER 3

DESIGN OF MICROCONTROLLER BASED HEART RATE METER

INTRODUCTION:

The design of microcontroller based heart rate meter comprises of IR sen-

sors, Microcontroller, Op-amp, voltage regulator, power-supply, finger Pulse

module

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high transitions of the wave. This time in micro seconds is converted in steps of 4 ms

for comparison with the values already stored in the look-up table. This

number is used to find (from the look-up table) the heart rate in beats per minute. The

number so obtained is converted into a 3-digit number in binary-coded decimal (BCD)

form.

BLOCK DIAGRAM :

Fig.3.1

CHAPTER 4

HARDWARE DEVELOPMENT

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CIRCUIT-DIAGRAM

fig.4

WORKING PRINCIPLE:

Basically, the device consists of an infrared transmitter LED and an infrared

sensor photo-transistor.

The transmitter-sensor pair is clipped on one of the fingers

The LED emits infrared light to the finger of the subject.

The photo-transistor detects this light beam and measures the change of blood

volume through the finger artery.

This signal, which is in the form of pulses is then amplified and filtered suit-

ably and is fed to a low-cost microcontroller for analysis and display.

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The microcontroller counts the number of pulses over a fixed time interval and

thus obtains the heart rate of the subject.

These sensor clips consist of only a pair of IR photo transistor and receiver

LEDs enclosed in a specially designed plastic clip housing and cable with stereo

jack plug.

FINGER CLIP MODELS:

fig.4.1

The IR transmitter and receiver are encapsulated in this clipping device

fig.4.2

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CHAPTER 5

HARDWARE REQUIREMENTS

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16

S.NO NAME OF THE COMPONENT RANGE QUANTITY

1 LM358 QUAD OPERATIONAL AMPLIFIER - 1

2 7805, VOLTAGE REGULATOR 5V 1

3 AT89S52 MICROCONTROLLER - 1

4 CRYSTAL OSCILLATOR - 1

5 BC548 NPN TRANSISTOR - 1

6 2 X16 LCD - 1

7 IN4007 RECTIFIER DIODE - 3

8 ZENER DIODE 6.8V

3.3V

1

1

9 LED - 1

10 RESISTORS(ohms)

LIGHT DEPENDENT RESISTORS

0.1k

1k

10k

22k

100k

-

1

2

1

1

1

1

11 CAPACITORS(micro farads) 1 f,63V

33pf

100f

470f,25V

1

2

1

1

12 230V AC PRIMARY TO 12V-0-12V,500mA SEC-

ONDARY TRANSFORMER

- 1

13 FINGER PULSE MODULE - 1

14 VARIABLE RESISORS 0-10k 1


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Table.1

CHAPTER 6

COMPONENTS DESCRIPTION

6.1 LM358 QUAD OPERATIONAL AMPLIFIER

Description:

The LM358 series consists of two independent high gain,internally frequency

compensated Operational amplifiers which were designed Specially to operate

from a single power supply over a wide range of voltages.

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Fig.6.1.1

Applications include transducer amplifiers, dc amplification blocks, and all the

conventional operational amplifier circuits that now can be implemented more

easily in single-supply-voltage systems

Features:

Wide bandwidth(unity gain): 1 MHz

Low input offset voltage : 2 mV

Large dc voltage gain : 100 dB

Differential input voltage range equal to the power supply voltage.

Power drain suitable for battery operation.

Large output voltage swing: 0VDC to VCC-1.5VDC.

PIN CONNECTIONS(TOP VIEW):

Fig .6.1.2

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6.2 7805, 5V REGULATOR

Description:

The 7800 series of three-terminal positive regulator are available in the

TO-220/D-PAK package and with several fixed output voltages, making them useful in

a wide range of applications. Each type employs internal current limiting, thermal shut

down and safe operating area protection, making it essentially indestructible.

Fig 6.2.1

If adequate heat sinking is provided, they can deliver over 1A output cur-

rent. Although designed primarily as fixed voltage regulators, these devices can be

used with external components to obtain adjustable voltages and currents.

Features:

Output Current up to 1A

Output Voltages of 5, 6, 8, 9, 10, 12, 15, 18, 24V

Thermal Overload Protection

Short Circuit Protection

Output Transistor Safe Operating Area Protection

6.3 2X16 LIQUID CRYSTAL DISPLAY

Description:

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Liquid Crystal Display also called as LCD is very helpful in providing user interface as

well as for debugging purpose. The most common type of LCD controller is HITACHI

44780 which provides a simple interface between the controller & an LCD. These

LCD's arevery simple to interface with the controller as well as are cost effective

Pin Symbol Function

1 Vss Ground

2 Vdd Supply Voltage

3 Vo Contrast Setting4 RS Register Select

5 R/W Read/Write Select

6 En Chip Enable Signal

7-14 DB0-DB7 Data Lines

15 A/Vee Gnd for the backlight

16 K Vcc for backlight

Table.2

Fig 6.3.1

The LCD requires 3 control lines (RS, R/W & EN) & 8 (or 4) data lines. The

number on data lines depends on the mode of operation.

If operated in 8-bit mode then 8 data lines + 3 control lines i.e. total 11 lines are

required. And if operated in 4-bit mode then 4 data lines + 3 control lines i.e. 7lines are required.

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How do we decide which mode to use..? Its simple if you have sufficient data

lines you can go for 8 bit mode & if there is a time constrain i.e. display should

be faster then we have to use 8-bit mode because basically 4-bit mode takes

twice as more time as compared to 8-bit mode.

The 10k Potentiometer controls the contrast of the LCD panel

6.4 CRYSTAL OSCILLATOR

Description:

Fig 6.4.1

Figure 1. shows the crystal equivalent circuit. R is the effective series resistance, L

and C are the motional inductance and capacitance of the crystal. CP is the shunt

capacitance due to the crystal electrodes.

When the crystal is operating in parallel resonant mode it looks inductive.

The frequency of operation in this mode is defined by the load on the crystal.

The crystal manufacturer should specify the load capacitance CL for parallel resonant

crystals. In this mode the frequency of oscillation is given by the equation

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Crystal oscillator circuit:

Fig6.4.2

Features:

Wide range of operating supply voltage: 1.50V to5.5V

Regulated voltage drive oscillator circuit for reduced power consumption and

crystal drive current

Optimized low crystal drive current oscillation for miniature crystal units

6.5 BC547 NPN TRANSISTOR

Description:

The design of a transistor allows it to function as an amplifier or

a switch. This is accomplished by using a small amount of electricity to control

a gate on a much larger supply of electricity, much like turning a valve to con-

trol a supply of water .

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Fig 6.5.1

Transistors are composed of three parts a base , a collector , and an

emitter . The base is the gate controller device for the larger electrical supply .

The collector is the larger electrical supply , and the emitter is the outlet for that

supply . By sending varying levels of current from the base , the amount of cur-

rent flowing through the gate from the collector may be regulated. In this way ,

a very small amount of current may be used to control a large amount of cur-

rent , as in an amplifier . The same process is used to create the binary code for

the digital processors but in this case a voltage threshold of five volts is needed

to open the collector gate . In this way , the transistor is being used as a switch

with a binary function: five volts ON , less than five volts OFF .

Features:

Low current (max. 100mA)

Low voltage (max. 65 V).

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Fig 6.5.2

6.6 DIODES

In electronics , a diode is a two - terminal electronic component that

conducts electric current in only one direction. The term usually refers to a

semiconductor diode , the most common type today . This is a crystalline block

of material connected to two electrical terminals . A vacuum tube diode ( now lit-

tle used except in some high power technologies ) is a vacuum tube with two

electrodes ; a plate and a cathode .

The most common function of a diode is to allow an electric current to

pass in one direction ( called the diode'sforwarddirection ) while blocking cur-

rent in the opposite direction ( the reverse direction ) . Thus , the diode can be

thought of as an electronic version of a check valve . This unidirectional behavior

is called rectification, and is used to convert alternating current to direct current ,

and to extract modulation from radio signals in radio receivers .

6.6.1 1N4007 RECTIFIER DIODE

24
http://en.wikipedia.org/wiki/Electronicshttp://en.wikipedia.org/wiki/Terminal_(electronics)http://en.wikipedia.org/wiki/Electronic_componenthttp://en.wikipedia.org/wiki/Electric_currenthttp://en.wikipedia.org/wiki/Vacuum_tubehttp://en.wikipedia.org/wiki/Electrodehttp://en.wikipedia.org/wiki/Plate_electrodehttp://en.wikipedia.org/wiki/Cathodehttp://en.wikipedia.org/wiki/Check_valvehttp://en.wikipedia.org/wiki/Rectification_(electricity)http://en.wikipedia.org/wiki/Alternating_currenthttp://en.wikipedia.org/wiki/Direct_currenthttp://en.wikipedia.org/wiki/Modulationhttp://en.wikipedia.org/wiki/Electronicshttp://en.wikipedia.org/wiki/Terminal_(electronics)http://en.wikipedia.org/wiki/Electronic_componenthttp://en.wikipedia.org/wiki/Electric_currenthttp://en.wikipedia.org/wiki/Vacuum_tubehttp://en.wikipedia.org/wiki/Electrodehttp://en.wikipedia.org/wiki/Plate_electrodehttp://en.wikipedia.org/wiki/Cathodehttp://en.wikipedia.org/wiki/Check_valvehttp://en.wikipedia.org/wiki/Rectification_(electricity)http://en.wikipedia.org/wiki/Alternating_currenthttp://en.wikipedia.org/wiki/Direct_currenthttp://en.wikipedia.org/wiki/Modulation


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Fig6.6.1

Features:

Low forward voltage drop

Low leakage current

High forward surge capability

6.6.2 LIGHT EMITTING DIODE (LED)

A light-emitting diode (LED), figure is a semiconductor diode that emits

light when an electrical current is applied in the forward direction of the device, as in

the simple LED circuit. The effect is a form of electroluminescence where incoherent

and narrow-spectrum light is emitted from p-n junction.

Fig.6.6.2

LEDs are widely used as indicator lights on electronic devices and in-

creasingly in higher power applications such as flashlights and area lighting. An LED is

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usually a small area (less than 1 mm) light source, often with optics added to the chip to

shape its radiation pattern and assist in reflection. The color of the emitted light depends

on the composition and condition of the semi conducting material used; and can be in-

frared, visible, or ultraviolet. Besides lighting, interesting applications include using

UV-LEDs for sterilization of water and disinfection of devices, and as a grow light to

enhance photosynthesis in plants.

6.7 RESISTORS AND CAPACITORS

RESISTOR:

A resistor is a two-terminal electronic component as shown in figure de-

signed to oppose an electric current by producing a voltage drop between its termi-

nals in proportion to the current, that is, in accordance with Ohms law: V=IR. The re-

sistance R is equal to the voltage drop Vacross the resistor divided by the currentI

through the resistor.

Fig 6.7.1

The ohm (symbol: ) is the SI unit of electrical resistance, named after

George Ohm. The most commonly used multiples and submultiples in electrical and

electronic usage are the milliohm, ohm, kilo-ohm, and mega-ohm.

CAPACITOR:

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A capacitor is an electrical/electronic device, as shown in figure that can

store energy in the electric field between a pair of conductors (called plates). The

process of storing energy in the capacitor is known as charging, and involves elec-

tric charges of equal magnitudes, but opposite polarity, building up on each plate.

A capacitor consists of two conductive electrodes, or plates, separated by a

dielectric, which prevents charge from moving directly between the plates. Charge may

however be moved indirectly by external influences, such as a battery connecting the

terminals. After removing the external influences, the charge on the plates persists.

The separated charges attract each other, and an electric field is present between the

plates.

Fig 6.7.2

Capacitors are often used in electric and electronic circuits as ener-

gy-storage devices. They can also be used to differentiate between high-fre-

quency and low-frequency signals. This property makes them useful in electronic fil-

ters. Charge separation in a parallel-plate capacitor causes an internal electric field. A

polarized dielectric spacer (orange) reduces the electric field and increase the capaci-

tance.

A property called the capacitance C, which is a measure of the charge

stored on each plate for a given voltage such that

q(t)=Cv(t)

For an ideal parallel plate capacitor.In SI unit, a capacitor has a capacitance of one

farad when one coulomb of charge storage corresponds to one volt between its plates.

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Since the farad is a very large unit, capacitance is usually expressed in microfarads

(F), nanofarads (nF), or picofarads (pF).

6.8 MICROCONTROLLER AT89S52

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

with 8Kbytes of in-system programmable Flash memory.

The device is manufactured using Atmels high-density nonvolatile memory

technology and is compatible with the industry-standard 80C51 instruction set

and pin out.

The on-chip Flash allows the program memory to be reprogrammed in-system

or by a conventional nonvolatile memory programmer.

By combining a versatile 8-bit CPU with in-system programmable Flash on

a monolithic chip, the Atmel AT89S52 is a powerful microcontroller which pro-

vides a highly-flexible and cost-effective solution to many embedded control

applications.

The AT89S52 provides the following standard features: 8K bytes of Flash, 256

bytes

of RAM, 32 I/O lines, Watchdog timer, two data pointers, three 16-bit

timer/counters, a six-vector two-level interrupt architecture, a full duplex serial

port, on-chip oscillator, and clock circuitry.

In addition, the AT89S52 is designed with static logic for operation down to

zero frequency and supports two software selectable power saving modes.

The Idle Mode stops the CPU while allowing the RAM, timer/counters, serialport, and interrupt system to continue functioning. The Power-down mode saves

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

until the next interrupt or hardware reset.

PIN DIAGRAM OF AT89S52 :

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Fig 6.8.1

BLOCK DIAGRAM OF AT89S52 :

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Fig 6.8.2

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

eight TTL inputs. When 1sare written to port 0 pins, the pins can be used as high impedance

inputs.

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

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

the internal pullups and can be used as inputs. As inputs,Port 1 pins that are externally being

pulled low will sourcecurrent (IIL) because of the internal pullups.

Port 2: Port 2 is an 8-bit bidirectional I/O port with internal pullups..The Port 2 output bufferscan sink/source four TTL inputs. When 1s are written to Port 2 pins, they are pulled high by

the internal pullups and can be used as inputs. As inputs ,Port 2 pins that are externally being

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

Port 3: Port 3 is an 8-bit bidirectional I/O port with internal pullups.The Port 3 output buffers can

sink/source four TTL inputs.When 1s are written to Port 3 pins, they are pulled high by

the internal pullups and can be used as inputs. As inputs,Port 3 pins that are externally being

pulled low will sourcecurrent (IIL) because of the pullups.

Table.3

Timer 2 Interrupt :

Timer 2 is a 16-bit Timer/Counter that can operate as either a timer or an event

counter. The type of operation is selected by bit C/T2 in the SFR T2CON

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Timer 2 has three operating modes: capture, auto-reload (up or down counting), and

baud rate generator. The modes are selected by bits in T2CON

It consists of two 8-bit registers, TH2 and TL2. In the Timer function, the TL2 register is

incremented every machine cycle. Since a machine cycle consists of 12 oscil-

lator periods , the count rate is 1/12 of the oscillator frequency.

6.9 PROGRAM :

;> TITLE : HEART RATE MONITERING SYSTEM

;> TARGET : AT89S52

;> STARTED : 02-08-2011

------------------------------------------------------------------------------------------------------

;>

;> INCLUDES :

$MOD51

;>

;------------------------------------------------------------------------------------------------------------

;>

;> HARD WARE DETAILS :

;>

;> DISPLAY ENEBLE - P2.5

DEN BIT P2.5

;> DISPLAY READ/WRITE - P2.6

DRW BIT P2.6

;> DISPLAY REG SELECT - P2.7

DRS BIT P2.7

;>;------------------------------------------------------------------------------------------------------------

;>

;> FLAGS:

BUSY_CHEK BIT 00H

PL_FLG BIT 01H

MIN_FLG BIT 02H

;>

;------------------------------------------------------------------------------------------------------------

;>

;> VARIABLES:

ADC_VAL DATA 30H

TMPR_VAL DATA 31H

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TMPR_VAH DATA 32H

PULSE DATA 33H

TCNT1 DATA 34H

TCNT2 DATA 35H

TPLS DATA 36H

PCNT DATA 37HPULSE1 DATA 38H

;>

;------------------------------------------------------------------------------------------------------------

;>

;> DEFINITIONS :

COM EQU 0fch ; command ;display headers

DAT EQU 0fdh ; data

EOL EQU 0feh ; end of line

;>

;------------------------------------------------------------------------------------------------------------

;>

;> VECTOR ADDRESESS:

ORG 0000H

ljmp RESET

ORG 0003H

lcall EXT_I0

reti

ORG 000BH

push ACC

push PSW

mov TH0, #0DBH

mov TL0, #0FFH

inc TCNT1

mov A, TCNT1

cjne A, #100D, SKIP_SEC

mov TCNT1, #00h

cpl P3.5

inc TCNT2

mov A, TCNT2

cjne A, #60D, SKIP_SEC

mov TCNT2, #00h

cpl P3.3

setb MIN_FLG

mov PULSE, TPLS

mov TPLS, #00h

SKIP_SEC:

pop PSW

pop ACCRETI

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;>

;------------------------------------------------------------------------------------------------------------

;>

RESET:

mov P3, #0FFH ; move all ports HIGH

mov P2, #0FFHmov P1, #0FFH

mov P0, #0FFH

mov sp, #065H ; init stack pointer

mov dptr, #INITIALISE

lcall MESSAGE

mov dptr, #NAME

lcall MESSAGE

lcall DLY

mov dptr, #COLLEGE

lcall MESSAGE

lcall DLY

mov dptr, #NAME1

lcall MESSAGE

lcall DLY

mov dptr, #NAME2

lcall MESSAGE

lcall DLY

mov dptr, #GUIDE

lcall MESSAGE

lcall DLY

mov dptr, #HOD

lcall MESSAGE

lcall DLY

mov dptr, #CLRSCR

lcall MESSAGE

mov TCON, #05H

mov TMOD, #21H

mov IE, #83H

setb TR0

mov TH0, #0DBH

mov TL0, #0FFH

mov TPLS, #00h

mov PULSE, TPLS

clr MIN_FLG

mov TCNT1, #00h

mov TCNT2, #00h

mov PCNT, #00h

clr PL_FLG

;>

;------------------------------------------------------------------------------------------------------------

;>MAIN:

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jnb MIN_FLG, DONT_RST_VAL

clr MIN_FLG

mov R7, #01H

lcall DISP_COM

lcall DLY1

DONT_RST_VAL:jb P3.7, RESET_PULSE

mov PULSE, #00H

mov TPLS, #00H

RESET_PULSE:

lcall DISP_PLS

ljmp MAIN

;>

;------------------------------------------------------------------------------------------------------------

;>

EXT_I0:

push ACC

push PSW

cpl P3.4

inc TPLS

mov A, TPLS

clr C

da A

mov TPLS, A

DONT_CNT_PLS:

pop PSW

pop ACC

ret ; return to message

;>

;------------------------------------------------------------------------------------------------------------

;>

MESSAGE: ; sub for sending charactors to display

push acc

MESSAGE1:

lcall READY ; Check weather display is ready

clr a ; Clr accumulator

movc a, @a+dptr ; Load accumulator with the contents of dptr

inc dptr ;

cjne a, #EOL, COMD ; If the data is not end of line goto comd

pop acc

ret ; if the data is end of line stop sending

COMD: ;

cjne a, #COM, DDATA ; if the data is not command goto dataclr DRS

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clr BUSY_CHEK

sjmp MESSAGE1 ; goto message again

DDATA: ;

cjne a, #DAT, SENDIT ; if the data is not data to be send goto comdsetb DRS

setb BUSY_CHEK


SENDIT: ;

mov P0, a ; place the data at port 1

clr DRW

nop

setb DEN ; send enable strobe

clr DEN ;


;>

;------------------------------------------------------------------------------------------------------------

;>

READY: ; sub to check display busy

clr DEN ; disable display buffer

mov P0, #0FFH ; set port1 in read mode

clr DRS

setb DRW

WAIT: ;

clr DEN ; send enable strobe

setb DEN ;

jb P0.7, WAIT ; if display is not send ready signal be in loop

clr DEN ; disable display buffer

jnb BUSY_CHEK, NO_DRS_SET

setb DRS

NO_DRS_SET:


;>

;------------------------------------------------------------------------------------------------------------

;>

DISP_LET:

lcall READY ; Check whether display is ready

setb DRS

setb BUSY_CHEK

mov P0, R7 ; place the data at port 1

clr DRW

nop


clr DEN ;


;>;------------------------------------------------------------------------------------------------------------

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;>

DISP_COM:

lcall READY ; Check whether display is ready

clr DRS

clr BUSY_CHEK

mov P0, R7 ; place the data at port 1clr DRW

nop


clr DEN ;


;>

;------------------------------------------------------------------------------------------------------------

;>

DISP_PLS:

mov DPTR, #PLSEH

lcall MESSAGE

mov A, PULSE

anl A, #0F0h

swap A

add A, #30H

mov R7, A

lcall DISP_LET

mov A, PULSE

anl A, #0Fh

add A, #30H

mov R7, A

lcall DISP_LET

RET ; END SUB

;>

;------------------------------------------------------------------------------------------------------------

;>

DLY:

mov r4, #0fh

GONE: mov r5, #00h

OUT: mov r6, #00h

IN: djnz r6, IN

djnz r5, OUT

djnz r4, GONE

ret

DLY1:

mov r4, #01h

GONE1: mov r5, #02hOUT1: mov r6, #00h

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IN1: djnz r6, IN1

djnz r5, OUT1

djnz r4, GONE1

ret

DLY2:

mov r4, #03hGONE2: mov r5, #00h

OUT2: mov r6, #00h

IN2: djnz r6, IN2

djnz r5, OUT2

djnz r4, GONE2

ret

DLY3:

mov r0, #25h

OUT3: mov r3, #00h

IN3: djnz r3, IN3

djnz r0, OUT3

ret

;>

;------------------------------------------------------------------------------------------------------------

;>

;> ROM TABLE AREA

;>

INITIALISE:

db COM, 30h, 30h, 30h, 30h, 3ch, 06h, 0ch, 01h, EOL

NAME:

db COM, 80h, DAT, ' HEART RATE ', COM, 0C0H, DAT,'MONITRING SYSTEM', EOL

COLLEGE:

db COM, 80h, DAT, 'ACE ENGG.COLLEGE', COM, 0C0H, DAT,' HYDERABAD ', EOL

NAME1:

db COM, 80h, DAT, 'SUBMITTED BY.. ', COM, 0C0H, DAT,'N.SHASHI KANTH ', EOL

NAME2:

db COM, 80h, DAT, 'M.KRUPAL KUMAR ', COM, 0C0H, DAT,'P.HARSHA VARDHAN', EOL

GUIDE:

db COM, 80h, DAT, 'GUIDED BY.. Mr.', COM, 0C0H, DAT,'C.SATYANARAYANA ', EOL

HOD:

db COM, 80h, DAT, 'OUR HOD.. Mr.', COM, 0C0H, DAT,'SURYA NARAYANA ', EOL

PLSEH:

db COM, 80h, DAT, 'PULSE = ', EOL

CLRSCR:

db COM, 01h, EOL

;>

;------------------------------------------------------------------------------------------------------------

;>

END

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CHAPTER 7

CONCLUSION

Since it has more advantages in many aspects compared with the disadvantages

it can be used widely

Examining of heart beat is very easy as if doesnt require much knowledge re-

garding circuitary.

Advantages:

If the clip is not adjusted properly then the accuracy comes down..

LCD displays are costly

Dis-advantages:

If the clip is not adjusted properly then the accuracy comes down..

LCD displays are costly

Applications:

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While this sounds so simple, it is an important aspect for any patient who

is suffering from heart disease, or someone recovering from an illness.

Now a days these digital heart rate meters have become very popular and

used in hospitals also

CHAPTER 8

FUTURE SCOPE

A graphical LCD can be used to display a graph of the change of heart rate over

time

Fig.8

By modifying this circuit and using two relays we can achieve a task of opening

and closing the door.

This circuit can be modified to sense the water level in a cistern and control the

water supply accordingly.

Sound can be added to the device so that a sound is output each time a pulse is

received

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REFERENCES

1. www.wikipedia.com

2. www.efymag.com

3. www.datasheetscatalog.com

4.www.heartratemoniter.co.uk
http://www.wikipedia.com/http://www.efymag.com/http://www.datasheetscatalog.com/http://www.wikipedia.com/http://www.efymag.com/http://www.datasheetscatalog.com/

Documents

Krupal Final