Anti Collision System For Railways

7/30/2019 Anti Collision System For Railways

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Anti-Collision System for Railways

Aim:

The aim of the project is to develop & launch an up-to-date and reliable control system which

can avoid collision automatically when found trains on same track using microcontroller

circuitry synchronized with central control unit for railways.

Need:

It is necessary to have an intelligent system which identifies the accident before it happens and

regulate the speed of the train and to stop it, if it is very close to the collision.

Working:

This project is implemented by using light sensors in mounted on engine of the train. The light

sensors will sense the light and give the indication of wrong track. The light sensor is constantly

monitored by a microcontroller and when it sense the wrong track, it is programmed to regulate

the speed and also to stop the train if it is necessary and at the same time alerting the central

control to stop the other train coming on the same track from the opposite direction.

Description:It mainly consists of following blocks:

1. Power Supply: It is a basic need of any circuit. We are using two supply of +5V & +12Vfor our system.

2. Microcontroller: This is the CPU (central processing unit) of our project. We are going touse a microcontroller of 8051 family. The various functions of microcontroller are:

Reading the digital input from sensors. Sending this data to LCD so that the person operating this project should get what

is going on. Operates the dam gates using stepper motor. Alerts the persons nearby the dam using loudspeakers.

3. LCD: We are going to use 16x2 alphanumeric Liquid Crystal Display (LCD) whichmeans it can display alphabets along with numbers on 2 lines each containing 16

characters.

4. Control Unit: The control unit consists of stepper motors which regulate the opening andclosing of dam gates.


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Datasheets:

1. LM78XX,3-Terminal 1A Positive Voltage RegulatorFeatures

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.

Description

The 78xx (sometimes LM78xx) is a family of self-contained fixed linear voltage regulator

integrated circuits. The 78xx family is commonly used in electronic circuits requiring a regulated

power supply due to their ease-of-use and low cost. For ICs within the family, the xx is replaced

with two digits, indicating the output voltage (for example, the 7805 has a 5 volt output, while

the 7812 produces 12 volts). The 78xx lines are positive voltage regulators: they produce a

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

which are complementary negative voltage regulators. 78xx and 79xx ICs can be used in

combination to provide positive and negative supply voltages in the same circuit.

78xx ICs have three terminals and are commonly found in the TO220 form factor, although

smaller surface-mount and larger TO3 packages are available. These devices support an input

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

35 or 40 volts, and typically provide 1 or 1.5 amps ofcurrent.

Internal Block Diagram
http://en.wikipedia.org/wiki/Linear_regulatorhttp://en.wikipedia.org/wiki/Integrated_circuitshttp://en.wikipedia.org/wiki/Voltagehttp://en.wikipedia.org/wiki/TO220http://en.wikipedia.org/wiki/TO3http://en.wikipedia.org/wiki/Amperehttp://en.wikipedia.org/wiki/Electric_currenthttp://en.wikipedia.org/wiki/Electric_currenthttp://en.wikipedia.org/wiki/Amperehttp://en.wikipedia.org/wiki/TO3http://en.wikipedia.org/wiki/TO220http://en.wikipedia.org/wiki/Voltagehttp://en.wikipedia.org/wiki/Integrated_circuitshttp://en.wikipedia.org/wiki/Linear_regulator


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Typical Application

2. Microcontroller AT89S52

Features:

Compatible with MCS-51 Products

8K Bytes of In-System Programmable (ISP) Flash Memory-Endurance: 10,000 Write/Erase

Cycles

4.0V to 5.5V Operating Range

Fully Static Operation: 0 Hz to 33 MHz

Three-level Program Memory Lock

256 x 8-bit Internal RAM

32 Programmable I/O Lines

Three 16-bit Timer/Counters

Eight Interrupt Sources

Full Duplex UART Serial Channel

Low-power Idle and Power-down Modes

Interrupt Recovery from Power-down Mode

Watchdog Timer

Dual Data Pointer


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Power-off Flag

Fast Programming Time

Flexible ISP Programming (Byte and Page Mode)

Green (Pb/Halide-free) Packaging Option

Description:

The AT89S52 is a low-power, high-performance CMOS 8-bit microcomputer with 8K bytes of

in-system programmable Flash memory. The device is manufactured using Atmels high-density

nonvolatile memory technology and is compatible with the industry-standard MCS-51

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 Flash on a monolithic chip, the Atmel AT89S52 is a powerful microcomputer which

provides a highly-flexible and cost-effective solution to many embedded control applications.

Pin Configurations


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Internal Block Diagram


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Pin Description

VCC- Supply voltage

GND- Ground

RST- Reset input. A high on this pin for two machine cycles while the oscillator is running

resets the device.

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

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

inputs. Port 0 may also be configured to be the multiplexed low order address/data bus during

accesses to external program and data memory. In this mode P0 has internal pull ups. Port 0 also

receives the code bytes during Flash programming, and outputs the code bytes during program

verification. External pull ups are required during program verification.

Port 1- Port 1 is an 8-bit bi-directional I/O port with internal pull ups. The Port 1 output buffers

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

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

low will source current (IIL) because of the internal pull ups. Port 1 also receives the low-order

address bytes during Flash programming and verification.

Port 2- Port 2 is an 8-bit bi-directional I/O port with internal pull ups. The Port 2 output buffers


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

low will source current (IIL) because of the internal pull ups. Port 2 emits the high-order address

byte during fetches from external program memory and during accesses to external data memory

that uses 16-bit addresses (MOVX @ DPTR). In this application, it uses strong internal pull-ups

when emitting 1s. During accesses to external data memory that uses 8-bit addresses (MOVX @

RI), Port 2 emits the contents of the P2 Special Function Register. Port 2 also receives the high-

order address bits and some control signals during Flash programming and verification.

Port 3- Port 3 is an 8-bit bi-directional I/O port with internal pull-ups. The Port 3 output buffers


internal pull ups and can be used as inputs. Port 3 also receives some control signals for Flash


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programming and verification .As inputs, Port 3 pins that are externally being pulled low will

source current (IIL) because of the pull ups. Port 3 also serves the functions of various special

features of the AT89C51 as listed below:

ALE/PROG- Address Latch Enable output pulse for latching the low byte of the address during

accesses to external memory. This pin is also the program pulse input (PROG) during Flash

programming. In normal operation ALE is emitted at a constant rate of 1/6 the oscillator

frequency, and may be used for external timing or clocking purposes. Note, however, that one

ALE pulse is skipped during each access to external Data Memory. If desired, ALE operation

can be disabled by setting bit 0 of SFR location 8EH. With the bit set, ALE is active only during

a MOVX or MOVC instruction. Otherwise, the pin is weakly pulled high. Setting the ALE-

disable bit has no effect if the microcontroller is in external execution mode.

PSEN- Program Store Enable is the read strobe to external program memory. When the

AT89C51 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.

EA/VPP- External Access Enable. EA must be strapped to GND in order to enable the device to

fetch code from external program memory locations starting at 0000H up to FFFFH. Note,

however, that if lock bit 1 is programmed, EA will be internally latched on reset. EA should be


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Interface Translation Battery-Powered RS-232 Systems Multi drop RS-232 Networks

Internal Diagram


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16 x 2 Character LCD

A liquid crystal display (LCD) is a thin, flat electronic visual display that uses the light

modulating properties ofliquid crystals (LCs). LCs do not emit light directly.

They are used in a wide range of applications, including computer monitors, television,

instrument panels, aircraft cockpit displays, signage, etc. They are common in consumer devices

such as video players, gaming devices, clocks, watches, calculators, and telephones. LCDs havedisplaced cathode ray tube (CRT) displays in most applications. They are usually more compact,

lightweight, portable, less expensive, more reliable, and easier on the eyes.] They are available in

a wider range of screen sizes than CRT and plasma displays, and since they do not use

phosphors, they cannot suffer image burn-in.

Structure of LCD

LCDs are more energy efficient and offer safer disposal than CRTs. Its low electrical power

consumption enables it to be used in battery-powered electronic equipment. It is an

electronically-modulated optical device made up of any number of pixels filled with liquid

crystals and arrayed in front of a light source (backlight) or reflector to produce images in colour

or monochrome. The earliest discovery leading to the development of LCD technology, the

discovery of liquid crystals, dates from 1888.
http://en.wikipedia.org/wiki/Electronic_visual_displayhttp://en.wikipedia.org/wiki/Liquid_Crystalshttp://en.wikipedia.org/wiki/Computer_monitorhttp://en.wikipedia.org/wiki/Televisionhttp://en.wikipedia.org/wiki/Flight_instrumentshttp://en.wikipedia.org/wiki/Signagehttp://en.wikipedia.org/wiki/Clockhttp://en.wikipedia.org/wiki/Calculatorhttp://en.wikipedia.org/wiki/Telephonehttp://en.wikipedia.org/wiki/Cathode_ray_tubehttp://en.wikipedia.org/wiki/Plasma_displayhttp://en.wikipedia.org/wiki/Battery_%28electricity%29http://en.wikipedia.org/wiki/Electronicshttp://en.wikipedia.org/wiki/Electro-optic_modulatorhttp://en.wikipedia.org/wiki/Pixelhttp://en.wikipedia.org/wiki/Liquid_crystalhttp://en.wikipedia.org/wiki/Liquid_crystalhttp://en.wikipedia.org/wiki/Light#Light_sourceshttp://en.wikipedia.org/wiki/Backlighthttp://en.wikipedia.org/wiki/Reflector_%28photography%29http://en.wikipedia.org/wiki/Monochromehttp://en.wikipedia.org/wiki/Monochromehttp://en.wikipedia.org/wiki/Reflector_%28photography%29http://en.wikipedia.org/wiki/Backlighthttp://en.wikipedia.org/wiki/Light#Light_sourceshttp://en.wikipedia.org/wiki/Liquid_crystalhttp://en.wikipedia.org/wiki/Liquid_crystalhttp://en.wikipedia.org/wiki/Pixelhttp://en.wikipedia.org/wiki/Electro-optic_modulatorhttp://en.wikipedia.org/wiki/Electronicshttp://en.wikipedia.org/wiki/Battery_%28electricity%29http://en.wikipedia.org/wiki/Plasma_displayhttp://en.wikipedia.org/wiki/Cathode_ray_tubehttp://en.wikipedia.org/wiki/Telephonehttp://en.wikipedia.org/wiki/Calculatorhttp://en.wikipedia.org/wiki/Clockhttp://en.wikipedia.org/wiki/Signagehttp://en.wikipedia.org/wiki/Flight_instrumentshttp://en.wikipedia.org/wiki/Televisionhttp://en.wikipedia.org/wiki/Computer_monitorhttp://en.wikipedia.org/wiki/Liquid_Crystalshttp://en.wikipedia.org/wiki/Electronic_visual_display


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FEATURES

5 x 8 dots with cursor

Built-in controller (KS 0066 or Equivalent)

+ 5V power supply (Also available for + 3V)

1/16 duty cycle

B/L to be driven by pin 1, pin 2 orpin 15, pin 16 or A.K (LED)

N.V. optional for + 3V power supply

Pin Description

Pin Number Symbol Function

1 Vss GND

2 Vdd + 3V or + 5V

3 Vo Contrast Adjustment

4 RS H/L Register Select Signal

5 R/W H/L Read/Write Signal

6 E H L Enable Signal

7 DB0 H/L Data Bus Line









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15 A/Vee+ 4.2V for LED/Negative

Voltage Output

16 K Power Supply for B/L (OV)

Cost:

Part Name Quantity Price(in Rs.)

Microcontroller 89S52 1 50

LCD 1 120

Max 232 1 20

Relay 4 120

IR Sensor 1 150

Smoke Sensor 1 150

PCB(Glass epoxy) 3 120

GSM Modem 1 2000

DB9 connector 1 10

DB9 cable 1 50

7812 & 7805 1each 20

Push Buttons 3 20

Transistors 4 30

Resistor 20

Capacitor 20

Jumper Wires 50

Total Rs.2950

Anti Collision System For Railways

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