Speed checker on highway using 8051

MAJOR PROJECT SPEED CHECKER ON HIGHWAY

DEPARTMENT OF ELECTRONICS & COMMUNICATION 1

CHAPTER 1

INTRODUCTION

1.1 INTRODUCTION TO PROJECT

A system designed to record and report on discrete activities within a process is called as

Tracking System. In the same procedure we have developed a methodology of vehicle

speed & direction system for robotics to control and achieve accurate direction speed for a

class of non-linear systems in the presence of disturbances and parameter variations by

using wireless communication technique.

While driving on highways, motorists should not exceed the maximum speed limit

permitted for their vehicle. However, accidents keep occurring due to speed violations

since the drivers tend to ignore their speedometers. This speed checker will come handy

for the highway traffic police as it will not only provide a digital display in accordance

with a vehicle’s speed but sound an alarm if the vehicle exceeds the permissible speed for

the highway. The system basically comprises two IR LED’s Transistor & receiver sensor

pairs, which are installed on the highway 100cm apart, with the transmitter and the receiver

of each pair on the opposite sides of the road. The system displays the time taken by the

vehicle in crossing this distance from one pair to the other from which the speed of the

vehicle can be calculated as follows:

Here,

Distance is the total distance between the pair of sensors.

Time is the interval between crossing the first sensor and second sensor.

Microcontroller 8051 is the heart of the system, which control all the function of the circuit.

It measures the speed and control the circuit through a programming flashed inside 8051.

IR sensor are used as a pair of eye that keep watching the speed of each vehicle crossing

the sensors. A seven segment display is used to display the total speed of the vehicle (After

calculation is done inside controller.).



1.2 BLOCK DIAGRAM

fig 1: Block Diagram



CHAPTER 2

WORKING OF THE SYSTEM

2.1 WORKING

In this project we use IR sensors to detect the presence of a vehicle. According to this

project, 2 IR sensors are placed apart with a fixed known distance. Whenever IR rays are

interrupted by a vehicle during first sensor the count up timer is started. When the other IR

sensor senses the presence of vehicle, the count up timer is stopped. As the distance and

time the IR receiver receives the IR signals is noted by microcontroller and from that we

need to calculate speed. Here speed is calculated from the well-known formula of speed

which is distance/time. The Seven segment display is used to display the speed of the

vehicle. The microcontroller is used to monitor the all control operations needed for the

project.

2.1.1 Power Supply

The 8051 microcontroller works on +5V DC. Now here we have 220V AC as the input. So

first of all, we need to step down the voltage using transformer. Here the transformer will

step down the 220V AC to 9V AC at 50Hz. To convert AC to DC, a bridge rectifier is

placed using 1N4007, a p-n diode. Two capacitor of 470µF & .01µF is used as a filter.

Now, this DC output is fed to a 7805 voltage regulator which will convert the DC input

into +5V DC.

Fig 2.1: Power supply



2.1.2 8051

8051 block consist of the P89V51RD2 microcontroller. It will run on the frequency of

about 11.0592 MHz. 8051 is the brain of the system. All the components will drive by the

instructions provided by the microcontroller through a programming code burn inside the

8051. Pin diagram of Microcontroller 8051 is shown below.

Fig 2.2: 8051 Pin diagram

2.2 CIRCUIT DIAGRAM

The main circuit diagram of the project is shown below.



Fig 2.3: Main circuit (a)

2.3 PCB LAYOUT

Fig 2.6: PCB Layout



2.3 PROGRAM

#include<reg51.h>

sfr LCD=0x80;

sbit RS=P2^6;

sbit EN=P2^7;

unsigned int a=0, i=0, v;

void tm();

void delay(unsigned char time)

unsigned int a,b;

for(a=0;a<time;a++)

for(b=0;b<1275;b++);

void lcdcmd(unsigned char value)

LCD=value;

RS=0;

EN=1;

delay(10);

EN=0;

void lcddata(unsigned char value)

LCD=value;

RS=1;

EN=1;

delay(10);

EN=0;

void lcd_init()



lcdcmd(0x38);

delay(20);

lcdcmd(0x0c);

delay(20);

lcdcmd(0x01);

delay(20);

lcdcmd(0x06);

delay(20);

void ISR_ex0(void) interrupt 0

while(1)

tm();

a++;

void ISR_ex1(void) interrupt 2

unsigned char m,n,temp,o;

v=100/a;

m=v/100;

temp=v%100;

n=temp/10;

o=temp%10;

lcdcmd(0xc6);

lcddata(m+48);

lcddata(n+48);

lcddata(o+48);

a=0;

lcddata('m');



lcddata('m');

lcddata('/');

lcddata('s');

lcddata('e');

lcddata('c');

lcddata(' ');

lcddata(' ');

void main()

unsigned char w[]="WELCOMESPEED=WAITING...";

IT0 = 1; // Configure interrupt 0 for falling edge on /INT0 (P3.2)

EX0 = 1; // Enable EX0 Interrupt

IT1 = 1; // Configure interrupt 1 for falling edge on /INT0 (P3.2)

EX1 = 1; // Enable EX1 Interrupt

EA = 1; // Enable Global Interrupt Flag

IP=0x04; // Priority of ex1 high

lcd_init();

lcdcmd(0x84);

for(i=0;i<7;i++)

lcddata(w[i]);

lcdcmd(0xc0);

for(i=7;i<13;i++)

lcddata(w[i]);

for(i=13;i<24;i++)

lcddata(w[i]);

while(1);

void tm()

int y=0;



for(y=0;y<15;y++)

TMOD=0x01;

TL0=0xFD;

TH0=0x4B;

TR0=1;

while(TF0==0);

TR0=0;

TF0=0;



CHAPTER 3

COMPONENTS USED IN THE PROJECT

3.1 COMPONENT LIST

1. INTEGRATED CIRCUIT

P89V51RD2

7805

2. SWITCH

PUSH-TO-ON Switch

3. DIODE

1N4007 PN Diode

4. CAPACITORS

1000µF 25V

22pF

100nF 50V

10µF 40V

5. RESISTORS

220Ω

470Ω

10 KΩ

SIP-Resistor 10KΩ

6. CRYSTAL

11.0592MHz

7. TRANSFORMER

8. LCD

9. IR LED

10. LED

11. PRESET



3.2 COMPONENT DESCRIPTIONS

3.2.1 INTEGRATED CIRCUIT

P89V51RD2

The P89V51RD2 is an 8051 microcontroller with 64 kB Flash and 1024 bytes of data

RAM.

Fig 3.1: P89V51RD2 Pin Diagram

P0.0 to P0.7 -Port 0: Port 0 is an 8-bit open drain bidirectional I/O port. Port 0 pins that

have ‘1’s written to them float, and in this state can be used as high-impedance inputs. Port

0 is also the multiplexed low-order address and data bus during accesses to external code

and data memory. In this application, it uses strong internal pull-ups when transitioning to

‘1’s. Port 0 also receives the code bytes during the external host mode programming, and

outputs the code bytes during the external host mode verification. External pull-ups are

required during program verification or as a general purpose I/O port.

P1.0 to P1.7 -Port 1: Port 1 is an 8-bit bidirectional I/O port with internal pull-ups. The

Port 1 pins are pulled high by the internal pull-ups when ‘1’s are written to them and can

be used as inputs in this state. As inputs, Port 1 pins that are externally pulled LOW will



source current (IIL) because of the internal pull-ups. P1.5, P1.6, P1.7 have high current

drive of 16 mA. Port 1 also receives the low-order address bytes during the external host

mode programming and verification.

P2.0 to P2.7 -Port 2: Port 2 is an 8-bit bidirectional I/O port with internal pull-ups. Port 2

pins are pulled HIGH by the internal pull-ups when ‘1’s are written to them and can be

used as inputs in this state. As inputs, Port 2 pins that are externally pulled LOW will source

current (IIL) because of the internal pull-ups. Port 2 sends the high-order address byte

during fetches from external program memory and during accesses to external Data

Memory that use 16-bitaddress (MOVX@DPTR). In this application, it uses strong internal

pull-ups when transitioning to ‘1’s. Port 2 also receives some control signals and a partial

of high-order address bits during the external host mode programming and verification.

P3.0 to P3.7 -Port 3: Port 3 is an 8-bit bidirectional I/O port with internal pull-ups. Port 3

pins are pulled HIGH by the internal pull-ups when ‘1’s are written to them and can be

used as inputs in this state. As inputs, Port 3 pins that are externally pulled LOW will source

current (IIL) because of the internal pull-ups. Port 3 also receives some control signals and

a partial of high-order address bits during the external host mode programming and

verification.

PSEN - Program Store Enable: PSEN is the read strobe for external program memory.

When the device is executing from internal program memory, PSEN is inactive

(HIGH).When the device is executing code from external program memory, PSEN is

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

each access to external data memory. A forced HIGH-to-LOW input transition on the

PSEN pin while the RST input is continually held HIGH for more than 10 machine cycles

will cause the device to enter external host mode programming.

RST -Reset: While the oscillator is running, a HIGH logic state on this pin for two machine

cycles will reset the device. If the PSEN pin is driven by a HIGH-to-LOW input transition

while the RST input pin is held HIGH, the device will enter the external host mode;

otherwise the device will enter the normal operation mode.

EA -External Access Enable: EA must be connected to VSS in order to enable the device

to fetch code from the external program memory. EA must be strapped to VDD for internal

program execution. The EA pin can tolerate a high voltage of 12 V.



ALE- Address Latch Enable: ALE is the output signal for latching the low byte of the

address during an access to external memory.

7805

The 78xx (also sometimes known as LM78xx) series of devices is a family of self-

contained fixed linear voltage regulator integrated circuits. The 78xx family is a very

popular choice for many electronic circuits which require a regulated power supply, due to

their ease of use and relative cheapness. When specifying individual ICs within this family,

the xx is replaced with a two-digit number, which indicates the output voltage the particular

device is designed to provide (for example, the 7805 has a 5 volt output, while the 7812

produces 12 volts).

Figure 3.2: IC 7805

The 78xx lines are positive voltage regulators, meaning that they are designed to produce

a voltage that is positive relative to a common ground. There is a related line of 79xx

devices which are complementary negative vo1623ltage regulators. 78xx and 79xx Ics can

be used in combination to provide both positive and negative supply voltages in the same

circuit, if necessary. 78xx Ics have three terminals and are most commonly found in the

TO220 form factor, although smaller surface-mount and larger TO3 packages are also

available from some manufacturers. These devices typically support an input voltage which

can be anywhere from a couple of volts over the intended output voltage, up to a maximum

of 35 or 40 volts, and can typically provide up to around 1 or 1.5 amps of current (though

smaller or larger packages may have a lower or higher current rating).



3.2.2 SWITCH

PUSH-TO-ON

Push-to-on switch holds the circuit conducting while the switch is pressed. But

when the switch is released, the circuit stops conducting.

On the other hand, two way switches doesn’t need to pressed continue. It do not require

the continue effort to on the circuit. It has two states. When the switch is slides to left,

switch gives 1 and if it slides to right, the output is 0.

Figure 3.4: PUSH-TO-ON Switch

3.2.3 DIODE

1N4007 PN DIODE

The diode used here is a p-n junction diode i.e. 1N4007. Its reverse breakdown

voltage is 1000V. This diode is used as the rectifier.

Figure 3.5: 1N4007

3.2.4 CAPACITORS

In the project, two types of capacitors are used.

1. Electrolytic (47µF 50V, 10µF 40V, 470µF 25V)



2. Ceramic Disc (33pF)

Electrolytic capacitors are polarized capacitors are made of oxide film on aluminum foils.

These are cheaper and easily available. The range of values typically varies from 1uF to

47000uF and large tolerance of 20%. The voltage ratings range up to 500V. They have

high capacitance to volume ratio and used for smoothing in power supply circuits or

coupling capacitors in audio amplifiers. These are available in both leaded and surface

mount packages. The capacitance value and voltage ratings are either printed in µF.

Figure 3.6: Electrolytic Capacitor

The non – polarized type ceramic capacitors which are also known as ‘Disc capacitors’ are

widely used these days. These are available in millions of varieties of cost and

performance. The features of ceramic capacitor depend upon: Type of ceramic dielectric

used in the capacitor which varies in the temperature coefficient and Dielectric losses. The

exact formulas of the different ceramics used in ceramic capacitors vary from one

manufacturer to another. The common compounds such as titanium dioxide, strontium

titanate, and barium titanateare the three main types available although other types such as

leaded disc ceramic capacitors for through hole mounting which are resin coated,

multilayer surface mount chip ceramic capacitors and microwave bare leadless disc

ceramic capacitors that are designed to sit in a slot in the PCB and are soldered in place



Figure 3.7: Ceramic Capacitor

3.2.5 RESISTORS

Resistor is a passive component used to control current in a circuit. Its resistance is given

by the ratio of voltage applied across its terminals to the current passing through it. Thus

a particular value of resistor, for fixed voltage, limits the current through it. They are

omnipresent in electronic circuits.

Figure 3.8: Resistor

The different value of resistances are used to limit the currents or get the desired voltage

drop according to the current-voltage rating of the device to be connected in the circuit.

For example, if an LED of rating 2.3V and 6mA is to be connected with a supply of 5V, a

voltage drop of 2.7V (5V-2.3V) and limiting current of 6mA is required. This can be

achieved by providing a resistor of 450 connected in series with the LED.



3.2.6 CRYSTAL

A quartz crystal resonator plays a vital role in electronics oscillator circuitry. Sometimes

mispronounced as crystal oscillator, it is rather a very important part of the feedback

network of the oscillator circuitry. Electronics oscillators are used in frequency control

application finding their usage in almost every industry ranging from small chips to

aerospace.

Figure 3.9: Crystal

A quartz crystal is the heart of such type of resonators. Their characteristics like high

quality factor (Q), stability, small size and low cost make them superior over other

resonators like LC circuit, turning forks, ceramic resonator etc.

The basic phenomenon behind working of a quartz crystal oscillator is the inverse piezo

electric effect i.e., when electric field is applied across certain materials they start

producing mechanical deformation. These mechanical deformation/movements are

dependent on the elementary structure of the quartz crystal. Quartz is one of the naturally

occurring materials which show the phenomena of piezo electricity; however for the

purpose of resonator it is artificially developed since processing the naturally occurring

quartz is difficult and costly process.

3.2.7 TRANSFORMER

The transformer is a static electro-magnetic device that transforms one alternating voltage

(current) into another voltage (current). However, power remains the same during the

transformation. Transformers play a major role in the transmission and distribution of ac

power.

Principle



Transformer works on the principle of mutual induction. A transformer consists of

laminated magnetic core forming the magnetic frame. Primary and secondary coils are

wound upon the two cores of the magnetic frame, linked by the common magnetic flux.

When an alternating voltage is applied across the primary coil, current flows in the primary

coil producing magnetic flux in the transformer core, this flux induces voltage in secondary

coil.

Transformers are classified as: -

(a) Based on position of the windings with respect to core i.e.

1) Core type transformer

2) Shell type transformer

(b) Transformation ratio:

1) Step up transformer

2) Step down transformer

a) Core & shell types:

Figure 3.10: Step-Up Transformer.

Figure 3.11: Step-Down Transformer

Transformer is simplest electrical machine, which consists of windings on the laminated

magnetic core. There are two possibilities of putting up the windings on the core.

1) Winding encircle the core in the case of core type transformer



2) Cores encircle the windings on shell type transformer.

b) Step up and Step down: In these voltages transformation takes place according to

whether the primary is high voltage coil or a low voltage coil.

1) Lower to higher-> Step up

2) Higher to lower-> Step down

3.2.8 LCD

LCD (Liquid Crystal Display) screen is an electronic display module and find a wide range

of applications. A 16x2 LCD display is very basic module and is very commonly used in

various devices and circuits. These modules are preferred over seven segments and other

multi segment LEDs. The reasons being: LCDs are economical; easily programmable; have

no limitation of displaying special & even custom characters (unlike in seven segments),

animations and so on. A 16x2 LCD means it can display 16 characters per line and there

are 2 such lines. In this LCD each character is displayed in 5x7 pixel matrix. This LCD has

two registers, namely, Command and Data. The command register stores the command

instructions given to the LCD. A command is an instruction given to LCD to do a

predefined task like initializing it, clearing its screen, setting the cursor position, controlling

display etc. The data register stores the data to be displayed on the LCD. The data is the

ASCII value of the character to be displayed on the LCD. Click to learn more about internal

structure of a LCD.

Figure 3.12: LCD



Figure 3.13: LCD Description

3.2.9 IR LED

Here the IR transmitter is nothing but the IR LED. It just looks like a normal LED but

transmits the IR signals. Since the IR rays are out of the visible range we cannot observe

the rays from the transmitter. These are infrared LEDs; the light output is not visible by

our eyes. They can be used as replacement LEDs for remote controls, night vision for

camcorders, invisible beam sensors, etc.

Fig 3.14: IR LED



3.2.10 LED

A light-emitting diode (LED) is a semiconductor light source. LEDs are used as indicator

lamps in many devices and are increasingly used for other lighting. Appearing as practical

electronic components in 1962, early LEDs emitted low-intensity red light, but modern

versions are available across the visible, ultraviolet, and infrared wavelengths, with very

high brightness. When a light-emitting diode is forward-biased (switched on), electrons are

able to recombine with electron holes within the device, releasing energy in the form of

photons. This effect is called electroluminescence and the color of the light

Figure3.15: LED

is determined by the energy gap of the semiconductor. LEDs present many advantages over

incandescent light sources including lower energy consumption, longer lifetime, improved

physical robustness, smaller size, and faster switching. LEDs powerful enough for room

lighting are relatively expensive and require more precise current and heat management

than compact fluorescent lamp sources of comparable output. As its name implies it is a

diode, which emits light when forward biased. Charge carrier recombination takes place

when electrons from the N-side cross the junction and recombine with the holes on the P

side. Electrons are in the higher conduction band on the N side whereas holes are in the

lower valence band on the P side. During recombination, some of the energy is given up in

the form of heat and light. In the case of semiconductor materials like Gallium arsenide



(GaAs), Gallium phosphide (GaP) and Gallium arsenide phosphide (GaAsP) a greater

percentage of energy is released during recombination and is given out in the form of light.

LED emits no light when junction is reversed biased.

3.2.11 PRESET

A preset is a three legged electronic component which can be made to offer varying

resistance in a circuit. The resistance is varied by adjusting the rotary control over it. The

adjustment can be done by using a small screw driver or a similar tool. The resistance does

not vary linearly but rather varies in exponential or logarithmic manner. Such variable

resistors are commonly used for adjusting sensitivity along with a sensor. The variable

resistance is obtained across the single terminal at front and one of the two other terminals.

The two legs at back offer fixed resistance which is divided by the front leg. So whenever

only the back terminals are used, a preset acts as a fixed resistor. Presets are specified by

their fixed value resistance.

Fig 3.16: Preset

3.3 COST ANALYSIS

Name Cost (Unit Price)

1. INTEGRATED CIRCUIT

P89V51RD2 300/-

7805 5/-

2. SWITCH

PUSH-TO-ON Switch 3/-

3. DIODE

1N4007 PN Diode 3/-



4. CAPACITORS

1000µF 25V 5/

33pF 1/

47µF 50V 2/-

10µF 40V 2/-

5. RESISTORS

8.2 KΩ 0.50/-

SIP-Resistor 10KΩ 10/-

6. CRYSTAL

11.0592MHz 15/-

7. TRANSFORMER 60/-

8. LCD 280/-

9. IR LED 50/-

10. LED 2/-

11. PRESET 10/-



CHAPTER 4

TESTING & PROBLEMS

4.1 TESTING PROCEDURE

First of all we do the continuity test to check whether there is any short circuit or not in our

PCB. We don’t apply the power supply to our circuit before testing, without power supply

testing is called COLD Testing. We test all the components used in our project. A brief

description is given below about testing procedure.

In electronics, a continuity test is the checking of an electric circuit to see if current flows

(that it is in fact a complete circuit). A continuity test is performed by placing a small

voltage (wired in series with an LED or noise-producing component such as a piezoelectric

speaker) across the chosen path. If electron flow is inhibited by broken conductors,

damaged components, or excessive resistance, the circuit is "open". Devices that can be

used to perform continuity tests include multi meters which measure current and

specialized continuity testers which are cheaper, more basic devices, generally with a

simple light bulb that lights up when current flows. Making sure something is

not connected. Sometimes a solder joint will short two connections. Or maybe your PCB

has mistaken on it and some traces were shorted by accident.

Figure 4.1: Continuity Testing.

This meter is very simple. When the probes are not touching, the display shows "1". When

you touch the tips together, the display changes to a three digit mode (it's displaying

resistance, which we will cover later) It also emits a beep. Set your meter to the

continuity/diode "bleep" test. Connect the red meter lead to the base of the transistor.

http://en.wikipedia.org/wiki/Electronics

http://en.wikipedia.org/wiki/Electric_circuit

http://en.wikipedia.org/wiki/Current_(electricity)

http://en.wikipedia.org/wiki/LED

http://en.wikipedia.org/wiki/Loudspeakers#Piezoelectric_speakers

http://en.wikipedia.org/wiki/Loudspeakers#Piezoelectric_speakers

http://en.wikipedia.org/wiki/Electrical_resistance

http://en.wikipedia.org/wiki/Multimeter

http://en.wikipedia.org/wiki/Continuity_tester

http://en.wikipedia.org/wiki/Light_bulb

http://s3.amazonaws.com/ladyadanet/make/x0xb0x/shorts_t.jpg

http://s3.amazonaws.com/ladyadanet/make/x0xb0x/shorts_t.jpg



Connect the black meter lead to the emitter. A good NPN transistor will read a junction

drop voltage of between 0.45v and 0.9v. A good PNP transistor will read "OL". Leave the

red meter lead on the base and move the black lead to the collector. The reading should be

the same as the previous test. Reverse the meter leads in your hands and repeat the test.

Now connect the black meter lead to the base of the transistor. Connect the red meter lead

to the emitter. A good PNP transistor will read a junction drop voltage of between 0.45v

and 0.9v. A good NPN transistor will read "OL". Leave the black meter lead on the base

and move the red lead to the collector. The reading should be the same as the previous test.

Finally place one meter lead on the collector, the other on the emitter. The meter should

read "OL". Reverse your meter leads. The meter should read "OL". This is the same for

both NPN and PNP transistors. With the transistors on a pcb in circuit, you may not get an

accurate reading, as other things in the circuit may affect it, so if you think a transistor is

suspect from the readings you have got, remove it from the pcb and test it out of circuit,

repeating the above procedure.

4.2 TESTING FOR POWER SUPPLY

Every component was checked for short circuit through multimeter.

Power supply is given & the output of the various components is tested.

Output of the transformer -9 volts A.C

Output of the rectifier – 9 volt D.C

Output of the regulator – 5 Volt D.C

Output of the regulator with load - 4.80 Volt D.C

4.3 PROBLEM FACED IN THE PROJECT

While building the project, there were some problems faced:

1. Testing of electronic components or circuit is very interesting work. In my project we

don’t faced any serious problem. By testing we got a shorted path in our circuit on PCB

and there are 3-4 tracks which are broken during etching process. We joint these tracks by

tinning.

2. The first problem were soldering, it were not easy to solder the components on the PCB,

so the method suggested by the guide were, to apply the solder mask.



CHAPTER 5

ADVANTAGES & APPLICATIONS

5.1 ADVANTAGES

The circuit is also running on +5V which is easier to generate.

They reduce the risk of accidents.

It is easy to implement.

It reduce the effort of many men.

5.2 DISADVANTAGES

Sometimes the circuit got failure and causes various problems.

5.3 APPLICATION

Bridge construction.

Highways.

Two lane road construction.

Emergency response.

Event Traffic control.



CONCLUSION

The project “SPEED CHECKER FOR HIGHWAYS” has been successfully designed and

tested. It has been developed by integrating features of all the hardware components used.

Presence of every module has been reasoned out and placed carefully thus contributing to

the best working of the unit. Secondly, using highly advanced IC’s and with the help of

growing technology the project has been successfully implemented. Finally we conclude

that “SPEED CHECKER FOR HIGHWAYS” is an emerging field and there is a huge

scope for research and development. It can be further advanced by using a CCTV camera

in the circuit. Whenever any vehicle crosses speed limit, camera captures the image of

number plate and through transport database finds the address of the owner and sends fine.



BIBLIOGRAPHY

1. http://www.engineersgarage.com/

2. http://engineeringactivity.com/

3. http://www.pantechsolutions.net/

4. http://www.8051projects.net/

5. http://www.dnatechindia.com/

http://www.engineersgarage.com/

http://engineeringactivity.com/

http://www.pantechsolutions.net/

http://www.8051projects.net/

http://www.dnatechindia.com/

Date post:	19-Aug-2014
Category:	Engineering
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Speed checker on highway using 8051

Engineering