automatic railway crossing using micro controller report

Automatic Railway Gate Control System

1.ABSTRACT

OBJECTIVE: The aim of this project is to Automate unmanned railway gate using mechatronics.

PROJECT DEFINATION:

The objective of this project is to manage the control system of railway gate using the microcontroller. When train arrives at the sensing point alarm is triggered at the railway crossing point so that the people get intimation that gate is going to be closed. Then the control system activates and closes the gate on either side of the track. once the train crosses the other end control system automatically lifts the gate. For mechanical operation of the gates DC geared motors are employed. Here we are using embedded controller built around the 8051 family (AT89C52) for the control according to the data pattern produced at the input port of the micro controller, the appropriate selected action will be taken.. The logic is produced by the program written in Embedded C language. The software program is written, by using the KEIL/SPJ micro vision environment. The program written is then converted in HEX code after simulation and burned on to microcontroller using FLASH micro vision.


WORKING METHODOLOGY:

Present project is designed using 8051 microcontroller to avoid railway accidents happening at unattended railway gates, if implemented in spirit. This project utilizes two powerful IR transmitters and two receivers; one pair of transmitter and receiver is fixed at up side (from where the train comes) at a level higher than a human being in exact alignment and similarly the other pair is fixed at down side of the train direction. Sensor activation time is so adjusted by calculating the time taken at a certain speed to cross at least one compartment of standard minimum size of the Indian railway. We have considered 5 seconds for this project. Sensors are fixed at 1km on both sides of the gate. We call the sensor along the train direction as ‘foreside sensor’ and the other as ‘after side sensor’. When foreside receiver gets activated, the gate motor is turned on in one direction and the gate is closed and stays closed until the train crosses the gate and reaches aft side sensors. When aft side receiver gets activated motor turns in opposite direction and gate opens and motor stops. Buzzer will immediately sound at the fore side receiver activation and gate will close after 5 seconds, so giving time to drivers to clear gate area in order to avoid trapping between the gates and stop sound after the train has crossed.

GATE CONTROL

Railways being the cheapest mode of transportation are preferred over all the other means .When we go through the daily newspapers we come across many railway accidents occurring at unmanned railway crossings. This is mainly due to the carelessness in manual operations or lack of workers. We, in this project has come up with a solution for the same. Using simple electronic components we have tried to automate the control of railway gates. As a train approaches the railway crossing from either side, the sensors placed at a certain distance from the gate detects the approaching train and accordingly controls the operation of the gate. Also an indicator light has been provided to alert the motorists about the approaching train.


Block Diagram of the System

IR Input Sensor

IR Out put Sensor

Geared Motor -1 Engine

Geared Motor -2 Engine

IR Engine Sensor

IR Engine Sensor

Geared Motor -1 Railway Gate

Geared Motor -2 Railway

Railway Signals

Red and green

8051micro

controller


2.INTRODUCTION

Introduction:The objective of this project is to manage the control system of railway gate using

the microcontroller. When train arrives at the sensing point alarm is triggered at the railway crossing point so that the people get intimation that gate is going to be closed. Then the control system activates and closes the gate on either side of the track. once the train crosses the other end control system automatically lifts the gate. For mechanical operation of the gates geared motors are employed. Here we are using embedded controller built around the 8051 family (AT89C52) for the control according to the data pattern produced at the input port of the micro controller, the appropriate selected action will be taken.. The logic is produced by the program written in Embedded C language. The software program is written, by using the KEIL micro vision environment. The program written is then converted in HEX code after simulation and burned on to microcontroller using FLASH micro vision.

AT89C51 MicrocontrollerThe Micro controller (AT89C51) is a low power; high performance CMOS 8-bit

micro controller with 4K bytes of Flash programmable and erasable read only memory (PEROM). The on-chip Flash allows the program memory to be reprogrammed in-system or by a conventional non-volatile memory programmer. By combining a versatile 8-bit CPU with Flash on a monolithic chip, the Atmel AT89C51 is a powerful microcomputer, which provides a highly flexible and cost-effective solution to many embedded control applications. By using this controller the data inputs from the smart card is passed to the parallel port of the pc and accordingly the software responds. The IDE for writing the embedded program used is KEI L software.

Keil Micro vision Integrated Development Environment.

Keil Software development tools for the 8051 micro controller family support every level of developer from the professional applications engineer to the student just learning about embedded software development.The industry-standard Keil C Compilers, Macro Assemblers, Debuggers, Real-time Kernels, and Single-board Computers support ALL 8051-compatible derivatives and help you get your projects completed on schedule.

The source code is written in assembly language .It is saved as ASM file with an extension. A51.the ASM file is converted into hex file using keil software. Hex file is dumped into micro controller using LABTOOL software. At once the file is dumped and the ROM is burnt then it becomes an embedded one.


3.CIRCUIT DIAGRAM


4.COMPONENTS

The project consists of three main parts:

8051 microcontroller IR Transmitter IR Receiver DC motor Circuit 8051 CONTROLLER

The I/O ports of the 8051 are expanded by connecting it to an 8255 chip. The 8255 is programmed as a simple I/O port for connection with devices such as LEDs, geared DC motors and sensors.

The following block diagram shows the various devices connected to the different ports of an 8255. The ports are each 8-bit and are named A, B and C. The individual ports of the 8255 can be programmed to be input or output, and can be changed dynamically. The control register is programmed in simple I/O mode with port A, port B and port C (upper) as output ports and port C (lower) as an input port.

IR CIRCUITS

This circuit has two stages: a transmitter unit and a receiver unit. The transmitter unit consists of an infrared LED and its associated circuitry.

IR TRANSMITTER The IR LED emitting infrared light is put on in the transmitting unit. To generate IR signal, 555 IC based astable multivibrator is used. Infrared LED is driven through transistor BC 548. IC 555 is used to construct an astable multivibrator which has two quasi-stable states. It generates a square wave of frequency 38kHz and amplitude 5Volts. It is required to switch ‘ON’ the IR LED.

IR RECEIVER: The receiver unit consists of a sensor and its associated circuitry. In receiver section, the first part is a sensor, which detects IR pulses transmitted by IR-LED. Whenever a train crosses the sensor, the output of IR sensor momentarily transits through a low state. As a result the monostable is triggered and a short pulse is applied to the port pin of the 8051 microcontroller. On receiving a pulse from the sensor circuit, the controller activates the circuitry required for closing and opening of the gates and for track switching. The IR receiver circuit is shown in the figure below.


L293D Dual H-Bridge Motor Driver

L293D is a dual H-Bridge motor driver, So with one IC we can interface two DC motors which can be controlled in both clockwise and counter clockwise direction and if you have motor with fix direction of motion the you can make use of all the four I/Os to connect up to four DC motors. L293D has output current of 600mA and peak output current of 1.2A per channel. Moreover for protection of circuit from back EMF ouput


diodes are included within the IC. The output supply (VCC2) has a wide range from 4.5V to 36V, which has made L293D a best choice for DC motor driver.

A simple schematic for interfacing a DC motor using L293D is shown below.

As you can see in the circuit, three pins are needed for interfacing a DC motor (A, B, Enable). If you want the o/p to be enabled completely then you can connect Enable to VCC and only 2 pins needed from controller to make the motor work.

As per the truth mentioned in the image above its fairly simple to program the microcontroller. Its also clear from the truth table of BJT circuit and L293D the programming will be same for both of them, just keeping in mind the allowed combinations of A and B. We will discuss about programming in C as well as assembly for running motor with the help of a microcontroller.


5.EMBEDDED SYSTEMS

Introduction:An Embedded system is a combination of computer hardware and software, and

perhaps additional mechanical or other parts, designed to perform a specific function.

Embedded systems are usually a part of larger, complex system. Dedicated

applications, designed to execute specific activities, are implemented and embedded in

systems. These embedded applications are required to collaborate with the other

components of an enclosed system. Embedded application components interact mostly

with the non-human external environment. They continuously collect data from sensors

or other computer components and process data within real-time constraints. Embedded

systems are usually associated with dedicated hardware and specific software.

Embedding an application into system

Application and system are closely tied together

Collaborative application

Dedicated H/W and specific S/W

Interaction with non-human external environment

Real-time systems are embedded systems


5.1 EMBEDDED PRODUCT DEVELOPMENT LIFE CYCLE

5.2 DESIGN CONSIDERATIONS FOR AN EMBEDDED SYSTEM

Understand user requirements

Choose optimum electronic chip

HLL/ALL

Algorithm

Coding/Editing Compiling/Assembling

Debugging

Testing

Simulator

S/W

PCB Layout design

Assembling components

Testing

H/W

ICE (In Circuit Emulator)

Embedded Product

S/W Side H/W Side

DOWNLOAD

Processor

Memory

Inputs Outputs


Introduction:

Unlike software designed for general-purpose computers, embedded software

cannot usually be run on other embedded system without significant modification. This is

mainly because of the incredible variety in the underlying hardware. The hardware in

each embedded system is tailored specifically to the application, in order to keep system

costs low. As a result, unnecessary circuitry is eliminated and hardware resources are

shared whenever possible.

In order to have software, there must be a place to store the executable code and

temporary storage for runtime data manipulation. These take the form of ROM and

RAM, respectively. All embedded systems also contain some type of inputs and outputs.

It is almost always the case that the outputs of the embedded system are a function of its

inputs and several other factors. The inputs to the system usually take the form of sensors

and probes, communication signals, or control knobs and buttons. The outputs are

typically displays, communication signals, or changes to the physical world.

Example of an Embedded System


Other common design requirement include -

Processing power

Memory

Development cost

Number of Units

Expected Lifetime

Reliability

Processing power

This is the amount of processing power necessary to get the hob done. A common

way to compare processing power is the MIPS (millions of instructions per second)

rating. Other important features of the processor need to be consider is register width,

typically ranges from 8 to 64 bits.

Memory:

The amount of memory (ROM and RAM) required holding the executable

software and data it manipulates. The amount of memory required can also affect the

processor selection. In general, the register width off a processor establishes the upper

limit of the amount of memory it can access.

Development cost:

The development cost of the hardware and software design processes is a fixed,

one-time cost, so it might be that money is no object or that this is the only accurate

measure of system cost.

Number of units:

The tradeoff between production cost and development cost is affected most by

the number of units expected to be produced and sold.

Expected lifetime:


This indicates how long must the system continue to function? This affects all

sorts of design decisions from the selection of hardware components to how much the

system may cost to develop and produce.

Reliability:

How reliable must the final product be? If it is a children’s toy, it doesn’t always

have to work right, but if it is part of a space shuttle or a car, it had sure better do what it

is supposed to each and every time.

The Basic Design – REALTIME:

Designing Embedded systems is a challenging task. Most of the challenge comes

from the fact that Embedded systems have to interact with real world entities. These

interactions can get fairly complex. A typical Emebbed system might be interacting with

thousands of such entities at the same time. For example, a telephone switching system

routinely handles calls from tens of thousands of subscriber. The system has to connect

each call differently. Also, the exact sequence of events in the call might vary a lot.

Embedded systems have to respond to external interactions in a predetermined

amount of time. Successful completion of an operation depends upon the correct and

timely operation of the system. Design the hardware and the software in the system to

meet the Realtime requirements. For example, a telephone switching system must feed

dial tone to thousands of subscribers within a recommended limit of one second. To meet

these requirements, the off hook detection mechanism and the software message

communication involved have to work within the limited time budget. The system has to

meet these requirements for all the calls being set up at any given time.

The designers have to focus very early on the Realtime response requirements.

During the architecture design phase, the hardware and software engineers work together

to select the right system architecture that will meet the requirements. This involves

deciding inter connectivity of the processors, link speeds, processor speeds, etc.

The main queries to be asked are:


Is the architecture suitable? If message communication involves too many

nodes, it is likely that the system may not be able to meet the Realtime

requirement due to even mild congestion. Thus a simpler architecture has a better

chance of meeting the Realtime requirements.

Are the processing components powerful enough? A CPU with really high

utilization will lead to unpredictable Realtime behavior. Also, it is possible that

the high priority tasks in the system will starve the low priority tasks of any CPU

time. This can cause the low priority tasks to misbehave.

Is the Operating System suitable? Assign high priority to tasks that are involved

in processing Realtime critical events. Consider preemptive scheduling if

Realtime requirements are stringent. When choosing the operating system, the

interrupt latency and scheduling variance should be verified.

o Scheduling variance refers to the predictability in task scheduling times.

For example, a telephone switching system is expected to feed dialtone in

less than 500 ms. This would typically involve scheduling three to five

tasks within the stipulated time. Most operating systems would easily meet

these numbers as far as the mean dialtone delay is concerned. But general

purpose operating systems would have much higher standard deviation in

the dialtone numbers.

o Interrupt Latency refers to the delay with which the operating system can

handle interrupts and schedule tasks to respond to the interrupt. Again,

Embedded Systems based on real-time operating systems would have

much lower interrupt latency.

6.MICROCONTROLLER


Introduction:Microcontrollers are "embedded" inside some other device (often a consumer

product) so that they can control the features or actions of the product. Another name for

a microcontroller, therefore, is "embedded controller."

Microcontrollers are dedicated to one task and run one specific program. The

program is stored in ROM (read-only memory) and generally does not change.

Microcontrollers are often low-power devices.

A microcontroller has a dedicated input device and often (but not always) has a

small LED or LCD display for output. A microcontroller also takes input from the

device it is controlling and controls the device by sending signals to different

components in the device.

For example, the microcontroller inside a TV takes input from the remote control

and displays output on the TV screen. The controller controls the channel selector,

the speaker system and certain adjustments on the picture tube electronics such as

tint and brightness. The engine controller in a car takes input from sensors such as

the oxygen and knock sensors and controls things like fuel mix and spark plug

timing. A microwave oven controller takes input from a keypad, displays output on

an LCD display and controls a relay that turns the microwave generator on and off.

A microcontroller is often small and low cost. The components are chosen to

minimize size and to be as inexpensive as possible.

A microcontroller is often, but not always, ruggedized in some way.

On the other hand, a microcontroller embedded inside a VCR hasn't been

ruggedized at all.

The actual processor used to implement a microcontroller can vary widely.

Atmel 89c51 Microcontroller Description


The AT89C51 is a low-power, high-performance CMOS 8-bit microcomputer

with 4K bytes of Flash programmable and erasable read only memory (PEROM) based

on the famous 8051 architecture. The device is manufactured using Atmel’s high-density

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

instruction set and pinout. 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 AT89C51 is

a powerful microcomputer which provides a highly-flexible and cost-effective solution to

many embedded control applications.

Features

The AT89C51 provides the following standard features:

Compatible with MCS-51 Products

Endurance: 1,000 Write/Erase Cycles

4K Bytes of In-System Reprogrammable Flash Memory

128 bytes of Internal RAM (128 x 8-bit)

32 Programmable I/O Lines

Two 16-bit Timer/Counters

Five vector two-level interrupt architecture

A full duplex serial port

Three-level Program Memory Lock

Six Interrupt Sources

BLOCK DIAGRAM:


Figure: Block Diagram of AT89c51 Microcontroller

PIN CONFIGURATIONS:


Figure: PDIP Type AT89c51 Pin Diagram

PIN DESCRIPTION

VCC Supply voltage.


GND Ground.

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



pins they are pulled high by the internal pull-ups and can be used as inputs.As inputs,


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.

Port 3




pins they are pulled high by the internal pull-ups and can be used as inputs. As inputs,


pull-ups.

Port 3 also serves the functions of various special features of the AT89C51 as listed

below:

Port Pin Alternate Functions

P3.0 RXD (serial input port)

P3.1 TXD (serial output port)

P3.2 INT0 (external interrupt 0)

P3.3 INT1 (external interrupt 1)

P3.4 T0 (timer 0 external input)

P3.5 T1 (timer 1 external input)

P3.6WR (external data memory Write

strobe)

P3.7RD (external data memory read

strobe)

Port 3 also receives some control signals for Flash programming and verification.

RST

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

running resets the device.

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.

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

AT89C51 is executing code from external program memory, is activated twice

each machine cycle, except that two activations are skipped during each access to

external data memory.

/VPP

External Access Enable 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, will be internally latched on reset.

should be strapped to VCC for internal program executions. This pin also receives

the 12-volt programming enable voltage (VPP) during Flash programming, for parts that

require 12-volt VPP.

XTAL1

Input to the inverting oscillator amplifier and input to the internal clock operating

circuit.

XTAL2


Output from the inverting oscillator amplifier

Oscillator Characteristics

XTAL1 and XTAL2 are the input and output, respectively, of an inverting

amplifier which can be configured for use as an on-chip oscillator, as shown in Figure 1.

Either a quartz crystal or ceramic resonator may be used.

To drive the device from an external clock source, XTAL2 should be left

unconnected while XTAL1 is driven as shown in Figure 2. There are no requirements on

the duty cycle of the external clock signal, since the input to the internal clocking

circuitry is through a divide-by-two flip-flop, but minimum and maximum voltage high

and low time specifications must be observed.

Figure1: Oscillator Connections

Note: C1, C2 = 30 pF 10 pF for Crystals

= 40 pF 10 pF for Ceramic Resonators

Figure 2: External Clock Drive Configuration


How Oscillator works

When quartz crystal is subjected to mechanical pressure, they produce

a measurable electrical voltage conversely when an electric current is applied to a crystal,

it will induce mechanical movement. If an ac is passed through the crystal plate the

charges oscillate back and front at the resonant frequency of crystal.

f=12 ((1+C/CP)/(LC)))

Quartz crystal exhibits a property called the piezo-electric effect that is they

produce an electric voltage. When subjected to pressure along certain direction of the

crystal because of this property quartz crystal has important application in electronics

industry for controlling the frequency of radio waves.When piezo-electric crystal is used

in place of LC circuit for higher frequency stability, the oscillator is called as crystal

oscillator.


Crystal oscillator is used for stability frequency for a long period of time. The

resolution of 0.01 nm/s can be obtained. Crystal operates between fp and fs frequency (a

very narrow bandwidth).

Status of External Pins during Idle and Power-down Modes

ModeProgram

MemoryALE Port 0 Port 1 Port 2 Port3

Idle Internal 1 1 Data Data Data Data

Idle External 1 1 Float Data Address Data

Power-

downInternal 0 0 Data Data Data Data

Power-

downExternal 0 0 Float Data Data Data

Program Memory Lock Bits

On the chip are three lock bits which can be left un-programmed (U) or can be

programmed (P) to obtain the additional features listed in the table below. When lock bit

1 is programmed, the logic level at the EA pin is sampled and latched during reset. If the

device is powered up without a reset, the latch initializes to a random value, and holds

that value until reset is activated. It is necessary that the latched value of EA be in

agreement with the current logic level at that pin in order for the device to function

properly.

Lock Bit Protection Modes


Program Lock Bits

Protection TypeLB1 LB2 LB3

1 U U U No program lock features

2 P U U

MOVC instructions executed from external

program memory are disabled from fetching code

bytes from internal memory, EA is sampled and

latched on reset, and further programming of the

Flash is disabled

3 P P U Same as mode 2, also verify is disabled

4 P P PSame as mode 3, also external execution is

disabled

Programming the Flash

The AT89C51 is normally shipped with the on-chip Flash memory array in the

erased state (that is, contents = FFH) and ready to be programmed. The programming

interface accepts either a high-voltage (12-volt) or a low-voltage (VCC) program enable

signal.

The low-voltage programming mode provides a convenient way to program the

AT89C51 inside the user’s system, while the high-voltage programming mode is

compatible with conventional third-party Flash or EPROM programmers.

Reading the Signature Bytes:

The signature bytes are read by the same procedure as a normal verification of

locations 030H, 031H, and 032H, except that P3.6 and P3.7 must be pulled to a logic low.

The values returned are as follows.

(030H) = 1EH indicates manufactured by Atmel

(031H) = 51H indicates 89C51

(032H) = FFH indicates 12V programming

(032H) = 05H indicates 5V programming.

Programming Interface


Every code byte in the Flash array can be written and the entire array can be

erased by using the appropriate combination of control signals. The write operation cycle

is self timed and once initiated, will automatically time itself to completion. All major

programming vendors offer worldwide support for the Atmel microcontroller series.

Please contact your local programming vendor for the appropriate software revision.

Flash Programming Modes

Mode RST PSEN ALE/PROGEA /

VPPP2.6 P2.7 P3.6 P3.7

Write Code Data H L H/12V L H H H

Read Code Data H L H H L L H H

Write

Lock

Bit-1 H L H/12V H H H H

Bit-2 H L H/12V H H L L

Bit-3 H L H/12V H L H L

Chip Erase H L H/12V H L L L

Read Signature

ByteH L H H L L L L

Note: Chip Erase requires a 10 ms PROG pulse.

EXTERNAL PROGRAM MEMORY READ CYCLE

External Data Memory Read Cycle


External Data Memory Write Cycle

External Clock Drive Waveforms


External Clock Drive

Symbol Parameter Min Max Units

1/tCLCL Oscillator Frequency 0 24 MHz

tCLCL Clock Period 41.6 ns

techs High Time 15 ns

talc Low Time 15 ns

talc Rise Time 20 ns

techs Fall Time 20 ns

7.HARDWARE DISCRIPTION

7.1 STEPER MOTOR


Introduction:Geared motors convert electrical energy into precise mechanical motion. These

motors rotate a specific incremental distance per each step. The number of steps executed

controls the degree of rotation of the motor’s shaft. This characteristic makes step motors

excellent for positioning applications. For example, a 1.8° step motor executing 100 steps

will rotate exactly 180° with some small amount of non-cumulative error. The speed of

step execution controls the rate of motor rotation. A 1.8° step motor executing steps at a

speed of 200 steps per second will rotate at exactly 1 revolution per second.

Geared motors can be very accurately controlled in terms of how far and how fast

they will rotate. The number of steps the motor executes is equal to the number of pulse

commands it is given. A step motor will rotate a distance and at a rate that is proportional

to the number and frequency of its pulse commands.

Basic Geared Motor System

The diagram above shows a typical step motor based system. All of these parts

must be present in one form or another. Each component’s performance will have an

effect on the others. By altering the frequency of the pulse train, the pulse generator can

instruct the motor to accelerate, run at a speed, decelerate or stop. A pulse generator must

be present otherwise the motor will not move. Next is the motor driver.

The driver takes the pulses from the pulse generator and determines how and

when the windings should be energized. The windings must be energized in a specific

sequence to generate motion. Finally there is the step motor itself. A step motor has two

primary parts; the rotor, the moving piece, and the stator, the stationary piece. The stator


contains coils of wire called windings. The rotor spins on bearings or bushings inside the

stator. All step motors operate through the principle of the rotor following a rotating

magnetic field created by sequencing the flow of current through the stator windings.

Each NMB step motor has two phases, which are groups of electrically connected

windings. As current is passed through each phase, the motor takes “steps” or small

movements to keep in synchronism with the magnetic field. The degree of rotation per

step depends on the style of driver used and the construction of the motor.

Step Motor Advantages:

• Accuracy & Repeatability – Ability to position accurately.

• Responsiveness & Quick Acceleration – Step motors have low rotor inertia,

allowing them to get up to speed quickly. This makes step motors an excellent choice for

short, quick moves.

• Excellent torque for their size – Step motors have the highest torque per cubic

inch of any motor.

• Positioning Stability – Unlike other types of motors, step motors can be held

completely motionless in their stopped position.

Construction and Operating the Hybrid STEP MOTOR

Figure 1a depicts a 1.8° hybrid step motor. The rotor contains a permanent

magnet similar to those found in permanent magnet step motors. Hybrid rotors are axially

magnetized, one end polarized north and the other polarized south. Both the rotor and the

stator assemblies of hybrid motors have tooth-like projections. To understand the rotor’s

interaction with the stator, examine the construction of a 1.8° (the most common

resolution) hybrid step motor.

The two cups are oriented so that the teeth of the top cup are offset to the teeth of

the bottom cup by 3.6°. Second, the stator has a two-phase construction. The winding

coils, 90° apart from one another, make up each phase. Each phase is wound so that the

poles 180° apart are the same polarity, while the poles 90° apart are the opposite polarity.

When the current in a phase is reversed, is the polarity, meaning that any winding coil


can be either a north pole or a south pole. As shown in fig. 1b below, when phase A is

energized, the windings at 12 o’clock and 6 o’clock are north poles and the windings at 3

o’clock and 9 o’clock are south poles.

The windings at 12 and 6 would attract the teeth of the magnetically south end of

the rotor, and windings at 3 and 9 would attract the teeth of the magnetically north end of

the rotor.

.

7.2 CAPACITORS Introduction:

An electrolytic capacitor is a type of capacitor typically with a larger capacitance per unit volume than other types, making them valuable in relatively high-current and low-frequency electrical circuits. This is especially the case in power-supply filters, where they store charge needed to moderate output voltage and current fluctuations, in


rectifier output, and especially in the absence of rechargeable batteries that can provide similar low-frequency current capacity. They are also widely used as coupling capacitors in circuits where AC should be conducted but DC should not; the large value of the capacitance allows them to pass very low frequencies.

The electrolytic capacitor was invented in 1886 by Charles Pollack. It was largely responsible for the development of mains-powered radio receivers, since it permitted the filtering of the 50-60 hertz power supplied to residences, after it was rectified to power the radio tubes. This was not practical without the small volume and low cost of electrolytic capacitors.

Construction

Aluminum electrolytic capacitors are constructed from two conducting aluminum foils, one of which is coated with an insulating oxide layer, and a paper spacer soaked in electrolyte. The foil insulated by the oxide layer is the anode while the liquid electrolyte and the second foil act as cathode. This stack is then rolled up, fitted with pin connectors and placed in a cylindrical aluminum casing. The two most popular geometries are axial leads coming from the center of each circular face of the cylinder, or two radial leads or lugs on one of the circular faces. Both of these are shown in the picture

Polarity

In aluminum electrolytic capacitors, the layer of insulating aluminum oxide on the surface of the aluminum plate acts as the dielectric, and it is the thinness of this layer that allows for a relatively high capacitance in a small volume. The aluminum oxide layer can withstand an electric field strength of the order of 109 volts per meter. The combination of high capacitance and high voltage result in high energy density.

Unlike most capacitors, electrolytic capacitors have a voltage polarity requirement. The correct polarity is indicated on the packaging by a stripe with minus signs and possibly arrowheads, denoting the adjacent terminal that should be more negative than the other. This is necessary because a reverse-bias voltage will destroy the center layer of dielectric material via electrochemical reduction (see redo reactions). Without the dielectric material the capacitor will short circuit, and if the short circuit current is excessive, then the electrolyte will heat up and either leak or cause the capacitor to explode.

Modern capacitors have a safety valve, typically either a scored section of the can, or a specially designed end seal to vent the hot gas/liquid, but ruptures can still be dramatic. Electrolytic can withstand a reverse bias for a short period of time, but they will conduct significant current and not act as a very good capacitor. Most will survive with no reverse DC bias or with only AC voltage, but circuits should be designed so that there is not a constant reverse bias for any significant amount of time. A constant forward bias is preferable, and will increase the life of the capacitor.


These are the different schematic symbols for electrolytic capacitors. The minus or N marked side of the physical capacitor is equivalent to the node opposite to the plus sign on its symbolic equivalent. Tip: Take notice of the shape of the symbols and the placement of the positive and negative nodes, because most schematics do not print the "+", but rely on the symbol itself instead.

note: caps in metal can have the color mark at the minus side !

Polarity of caps with wires:

axial: the minus wire is connected to the case, the plus wire is isolated. radial = single ended: a vertical color stripe indicates the minus side.

For the polarity of SMD caps see pica:

Electrolyte

The electrolyte is usually boric acid or sodium borate in aqueous solution together with various sugars or ethylene glycol which are added to retard evaporation. Care should be taken to avoid ingestion of or eye contact with the electrolyte, and any areas of the body where skin contact has occurred should be washed in good time. It is important to follow safe working practice and to use appropriate protective equipment, notably gloves and safety glasses, when working with the electrolyte. Some very old tantalum electrolytic, often called "Wet-slug", contain the more hazardous sulfuric acid, however most of these are no longer in service due to corrosion.

http://en.wikipedia.org/wiki/Image:Cap-elko-smd-polarity.jpg


Capacitance

The capacitance value of any capacitor is a measure of the amount of electric charge stored per unit of potential difference between the plates. The basic unit of capacitance is a farad, however this unit has been too large for general use until the invention of the Double-layer capacitor, so microfarad, nanofarad and microfarad are more commonly used. These are usually abbreviated to if or of, no and puff

Many conditions determine a capacitor's value, such as the thickness of the dielectric and the plate area. In the manufacturing process, electrolytic capacitors are made to conform to a set of preferred numbers. By multiplying these base numbers by a power of ten, any practical capacitor value can be achieved, which is suitable for most applications.

A standardized set of capacitor base numbers was devised so that the value of any modern electrolytic capacitor could be derived from multiplying one of the modern conventional base numbers 1.0, 1.5, 2.2, 3.3, 4.7 or 6.8 by a power of ten. Therefore, it is common to find capacitors with values of 10, 15, 22, 33, 47, 68, 100, 220, and so on. Using this method, values ranging from 0.1 to 4700 are common in most applications. Values are generally in microfarads (µF).

Most electrolytic capacitors have a tolerance range of 20 %, meaning that the manufacturer is stating that the actual value of the capacitor lies within 20 % of its labeled value. Selection of the preferred series ensures that any capacitor can be sold as a standard value, within the tolerance.


Super capacitor

MC and BC series super capacitors (up to 3000 farad capacitance) produced by Maxwell Technologies

Super capacitors, also known as ultra capacitors or electrochemical double layer capacitors (EDLC), are electrochemical capacitors that have an unusually high energy density when compared to common capacitors, typically on the order of thousands of times greater than a high-capacity electrolytic capacitor. For instance, a typical D-cell sized electrolytic capacitor will have a storage capacity measured in microfarads, while the same size super capacitor would store several farads, an improvement of about 10,000 times. Larger commercial super capacitors have capacities as high as 5,000 farads.

Super capacitors have a variety of commercial applications, notably in "energy smoothing" and momentary-load devices. Some of the earliest uses were motor startup capacitors for large engines in tanks and submarines, and as the cost has fallen they have started to appear on diesel trucks and railroad locomotives. More recently they have become a topic of some interest in the green energy world, where their ability to quickly soak up energy makes them particularly suitable for regenerative braking applications, whereas batteries have difficulty in this application due to slow charging times. If the LEES or Ester devices can be commercialized, they will make an excellent replacement for batteries in all-electric cars and plug-in hybrids, as they combine quick charging, temperature stability and excellent safety properties.


Concept

Comparison of construction diagrams of three capacitors. Left: "normal" capacitor, middle: electrolytic, right: super capacitor

In a conventional capacitor, energy is stored by the removal of charge carriers, typically electrons, from one metal plate and depositing them on another. This charge separation creates a potential between the two plates, which can be harnessed in an external circuit. The total energy stored in this fashion is a combination of the number of charges stored and the potential between the plates.

In contrast with traditional capacitors, super capacitors do not have a conventional dielectric, as such. They are based on a structure that contains an electrical double layer. In a double layer, the effective thickness of the "dielectric" is exceedingly thin—on the order of nanometers—and that, combined with the very large surface area, is responsible for their extraordinarily high capacitances in practical sizes.

In an electrical double layer, each layer by itself is quite conductive, but the physics at the interface where the layers are effectively in contact means that no significant current can flow between the layers. However, the double layer can withstand only a low voltage, which means that super capacitors rated for higher voltages must be made of matched series-connected individual super capacitors, much like series-connected cells in higher-voltage batteries.


History:

The super capacitor effect was first noticed in 1957 by General Electric engineers experimenting with devices using porous carbon electrode. It was believed that the energy was stored in the carbon pores and it exhibited "exceptionally high capacitance", although the mechanism was unknown at that time.

General Electric did not immediately follow up on this work, and it was Standard Oil of Ohio that eventually developed the modern version of the devices in 1966 after accidentally re-discovering the effect while working on experimental fuel cell designs. Their cell design used two layers of activated charcoal separated by a thin porous insulator. Standard Oil also failed to commercialize their invention, licensing the technology to NEC, who finally marketed the results as “super capacitors” in 1978, to provide backup power for maintaining computer memory. In 2005, the ultra capacitor market was between US $272 million and $400 million, depending on the source. It is rapidly growing, especially in the automotive sector.

Recently, all solid state micrometer-scale super capacitors based on advanced supersonic conductors had been recognized as critical electron component of future sub-voltage and deep-sub-voltage nanoelectronics and related technologies (22 nm technological node of CMOS and beyond).

Technology advantages

Due to the capacitor's high number of charge-discharge cycles (millions or more compared to 200–1000 for most commercially available rechargeable batteries) there were no disposable parts during the whole operating life of the device, which makes the device environmentally friendly. storing energy from other sources for load balancing purposes and then using any excess energy to charge the batteries only at opportune times.

Other advantages of super capacitors compared with rechargeable batteries are extremely low internal resistance or ESR, high efficiency (up to 97-98%), high output power, extremely low heating levels, and improved safety. According to ITS (Institute of Transportation Studies, Davis, CA) test results, the specific power of super capacitors can exceed 6 kW/kg at 95% efficiency

The idea of replacing batteries with capacitors in conjunction with novel alternative energy sources became a conceptual umbrella of the Green Electricity (GEL) Initiative, introduced by Dr. Alexander Bell.


Transportation applications

China is experimenting with a new form of electric bus (casabas) that runs without power lines using power stored in large onboard super capacitors, which are quickly recharged whenever the electric bus stops at any bus stop (under so-called electric umbrellas), and fully charged in the terminus. A few prototypes were being tested in Shanghai in early 2005. In 2006, two commercial bus routes began to use super capacitor buses; one of them is route 11 in Shanghai.

In 2001 and 2002, VAG, the public transport operator in Nuremberg, Germany tested a bus which used a diesel-electric drive system with super capacitors.

Other companies from the public transport manufacturing sector are developing super capacitor technology: The Transportation Systems division of Siemens AG is developing a mobile energy storage based on double-layer capacitors called Subic Energy Storage and also Sitars SES, a stationary version integrated into the trackside power supply. The company Cudgeled is also developing a super capacitor-based energy storage system.

Resistors, capacitors and inductors

Resistor values are always coded in ohms, capacitors in microfarads (pF), inductors in micro henries (µH), and transformers in volts.

band A is first significant figure of component value band B is the second significant figure band C is the decimal multiplier band D if present, indicates tolerance of value in percent (no color means 20%)

For example, a resistor with bands of yellow, violet, red, and gold will have first digit 4 (yellow in table below), second digit 7 (violet), followed by 2 (red) zeros: 4,700 ohms. Gold signifies that the tolerance is ±5%, so the real resistance could lie anywhere between 4,465 and 4,935 ohms.

Resistors manufactured for military use may also include a fifth band which indicates component failure rate (reliability); refer to MIL-HDBK-199 for further details.

The Standard EIA Color Code Table per EIA-RS-279 is as follows:

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

http://en.wikipedia.org/wiki/MIL-HDBK

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

http://www.okaphone.nl/calc/resistor.shtml?ohm=4700&tol=5

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

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

http://en.wikipedia.org/wiki/Henry_(inductance)

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

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

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

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

http://en.wikipedia.org/wiki/Image:Resistor_bands.png


Color 1st band 2nd band 3rd band (multiplier) 4th band (tolerance) Temp. Coefficient

Black 0 0 ×100

Brown 1 1 ×101 ±1% (F) 100 pap

Red 2 2 ×102 ±2% (G) 50 pap

Orange 3 3 ×103 15 pap

Yellow 4 4 ×104 25 pap

Green 5 5 ×105 ±0.5% (D)

Blue 6 6 ×106 ±0.25% (C)

Violet 7 7 ×107 ±0.1% (B)

Grey 8 8 ×108 ±0.05% (A)

White 9 9 ×109

Gold ×0.1 ±5% (J)

Silver ×0.01 ±10% (K)

None ±20% (M)

Note: red to violet are the colors of the rainbow where red is low energy and violet is higher energy.

http://en.wikipedia.org/wiki/Silver_(color)

http://en.wikipedia.org/wiki/Gold_(color)

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

http://en.wikipedia.org/wiki/Grey_(color)

http://en.wikipedia.org/wiki/Violet_(color)

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

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

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

http://en.wikipedia.org/wiki/Orange_(color)

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

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

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


7.3 POWER SUPPLY:

CIRCUIT DIAGRAM:

POWER SUPPLY:

To run the electronic gadget at home it is provided by some power supply. The

microcontroller used (at89c51) requires 12v D.C supply. The DTMF receiver used

(mt8870) requires 5v D.C. so design of these regulated power supply is also an important

part in hardware design. The A.C power supply from mains is taken and regulated using

the rectifiers.

For design of a regulated power supply components used are:

Transformer.

Diodes.

Rectifiers.

Regulated IC chips.

Capacitive filters.

Trans former:

A transformer is required to couple the mains to the actual power supply circuit.

This is required to isolate the mains from the actual regulated power supply circuit and

the other part of the kit. This isolation eliminates the dame of the kit to any power supply

variations or from a faulty shock.

IN4007

0

1

2

7805

LED

1

2

1000uf

TRANSFORMER

6

8

1IN4007

5

1k

2

1100uf

230 V AC

SUPPLY

50 HZ

4


For a transformer shown below:

:

Diodes:

In bride rectifier four diodes are used. The specifications of diodes are chosen

as:

PIV > input voltage.

Si diode is better.

Power dissipation is kept fixed with respect to current through the diode.

Junction capacitance need not be considered for frequencies <1 kHz.

RECTIFIERS: Rectification is a process of conversion of AC to DC. Here, the AC of transformer

output is given to the rectifier input, which converts it to DC output. Basically, bridge

rectifiers or diodes arranged in bridge called Diode arrangement are used for power

supply design.

A bridge rectifier makes use of four diodes in a bridge arrangement to achieve

full-wave rectification. This is a widely used configuration, both with individual diodes

wired as shown and with single component bridges where the diode bridge is wired

internally

V1 V2i1 i2

V1 = i2 = n1V2 i1 n2


Current Flow in the Bridge Rectifier

For both positive and negative swings of the transformer, there is a forward path

through the diode bridge. Both conduction paths cause current to flow in the same

direction through the load resistor, accomplishing full-wave rectification.

While one set of diodes is forward biased, the other set is reverse biased and

effectively eliminated from the circuit.

Diode Bridge:

A diode bridge is an arrangement of four diodes connected in a bridge circuit as

shownbelow, that provides the same polarity of output voltage for any polarity of the

input voltage. When used in its most common application, for conversion of alternating

current (AC) input into direct current (DC) output, it is known as a bridge rectifier. The

diagram describes a diode-bridge design known as a full-wave rectifier or Graetz circuit.

This design can be used to rectify single phase AC when no transformer center tap

is available

Bridge Rectifier Circuit:

The essential feature of this arrangement is that for both polarities of the voltage

at the bridge input, the polarity of the output is constant.

http://en.wikipedia.org/wiki/Image:Diodebridge1.png


Capacitors:

Capacitive filters are used stabilized or perfect regulation of the voltage. The

capacitive filters are opted because, they are more efficient. But they are also more

costly.

Different types of capacitors are:

1. Ceramic capacitors.

2. Electrolyte capacitors.

3. Paper/Mica capacitors.

4. Silver capacitors.

5. Tantalum capacitors.

Ceramic, Paper/Mica, Silver are nonpolarized capacitors. Electrolyte and Tantalum

are polarized capacitors. For high frequency, Ceramic capacitors are used. For low

frequencies, Electrolyte capacitors are used.

Linear regulated IC’s:Linear regulated IC’s are used for best regulated output. The output from these

regulated IC’s is given to microcontroller and DTMF receiver. These linear regulated

IC’s are self protective (any accidental shot circuit in the IC is grounded automatically).

78xx series ICs are used for ‘+ve’ supply.

79xx series ICs are used for ‘-ve’ supply.

78xx and 79xx series ICs are fixed voltage regulators. LM 317 is a variable

voltage regulator.


ULN2803buffer:

Features: 500-mA Rated Collector Current (Single Output)

High-Voltage Outputs . . . 50 V

Output Clamp Diodes

Inputs Compatible With Various Types of

logic

Relay Driver Applications

Compatible with ULN2800A Series

description/ordering information:The ULN2803A is a high-voltage, high-

current Darlington transistor array. The device

consists of eight nun Darlington pairs that feature

high-voltage outputs with common-cathode clamp

diodes for switching inductive loads. The collector-current rating of each Darlington pair

is 500 mA. The Darlington pairs may be connected in parallel for higher current

capability.

Applications include relay drivers, hammer drivers, lamp drivers, display drivers

(LED and gas discharge), line drivers, and logic buffers. The ULN2803A has a 2.7-

kseries base resistor for each Darlington pair for operation directly with TTL or 5-V

CMOS devices.


Logic diagram:

LOGIC DIAGRAM FOR THE ULN2803buffer

MNEMONICS


A useful mnemonic for remembering the first ten color codes matches the first letter of the color code, by order of increasing magnitude. There are many variations:

Bad Beer Rots Our Young Guts But Vodka Goes Well Bright Boys Rave Over Young Girls But Veto Getting Wed B. B. R O Y of Great Britain has a Very Good Wife Big Boys Race Our Young Girls But Violet Generally Wins Better Be Right Or Your Great Big Venture Goes West Black Beauty Ran Over Yellow Grass By Violent Grey Waters Bad Boys Race Over Yonder Green But Victory Goes Wanting Black Birds Roam Over Your Garden But Vultures Go West Bye Bye Rosie Off You Go Birmingham Via Great Weston

The word "Bad" in the first mnemonic and "Bright" in the second mnemonic are often replaced with the word "Black" since black comes before brown in the color code. While the second mnemonic is certainly the most offensive of these, all except the third lack a sobriety that might be desirable, especially in a teaching context. A more staid memory aide uses the fact that the central part of the code follows the color spectrum, without the i for indigo. That is,

Black Brown Roy G. Big Gray White

The most common variation of the mnemonic for the EIA color code generally doesn't stay posted on this page for long due to its choice of words which is more offensive to many today than when it was originated (mid 1920's). Refer to the discussion for details.

Besides the ten colors of the main value code, the tolerance code is often remembered as "for Gold or Silver" appended to the more offensive mnemonic, or "Get Some Now" where Now refers to none for 20%.

If it is difficult to recall that black comes before brown in the color code, it may be helpful to use the position of white at the end of the color code as a key to remember that black (and not brown) is at the beginning.

Other languages have other mnemonics for this color code. A rough translation of the French is "Don't eat anything or I'll beat you violently, big animal."

http://en.wikipedia.org/wiki/Talk:Electronic_color_code

http://en.wikipedia.org/wiki/Roy_G._Biv

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

http://en.wikipedia.org/wiki/Magnitude_(mathematics)

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


Examples

From top to bottom:

Green-Blue-Black-Black-Brown o 560 Ω ± 1%

Red-Red-Orange-Gold o 22,000 Ω ± 5%

Yellow-Violet-Brown-Gold o 470 Ω ± 5%

Blue-Gray-Black-Gold o 68 Ω ± 5%

Note: The sizes of the resistors depend only on the power they can dissipate, and do not affect their value.

What do resistors do?

Resistors limit current. In a typical application, a resistor is connected in series with an LED:

http://en.wikipedia.org/wiki/Image:Resistors_color_code.jpg


Enough current flows to make the LED light up, but not so much that the LED is damaged. Later in this Chapter, you will find out how to calculate a suitable value for this resistor. (LEDs are described in detail in Chapter 5.)

The 'box' symbol for a fixed resistor is popular in the UK and Europe. A 'zig-zag' symbol is used in America and Japan:

Resistors are used with transducers to make sensor subsystems. Transducers are electronic components which convert energy from one form into another, where one of the forms of energy is electrical. A light dependent resistor, or LDR, is an example of an input transducer. Changes in the brightness of the light shining onto the surface of the LDR result in changes in its resistance. As will be explained later, an input transducer is most often connected along with a resistor to to make a circuit called a potential divider. In this case, the output of the potential divider will be a voltage signal which reflects changes in illumination.

Microphones and switches are input transducers. Output transducers include loudspeakers, filament lamps and LEDs. Can you think of other examples of transducers of each type?


7.4 COLOR CODING

How can the value of a resistor be worked out from the colours of the bands? Each color represents a number according to the following scheme:

Number Color

0 black

1 brown

2 red

3 orange

4 yellow

5 green

6 blue

7 violet

8 grey

9 white

The first band on a resistor is interpreted as the FIRST DIGIT of the resistor value. For the resistor shown below, the first band is yellow, so the first digit is 4:


The second band gives the SECOND DIGIT. This is a violet band, making the second digit 7. The third band is called the MULTIPLIER and is not interpreted in quite the same way. The multiplier tells you how many nougats you should write after the digits you already have. A red band tells you to add 2 nougats. The value of this resistor is therefore 4 7 0 0 ohms, that is, 4 700 , or 4.7 . Work through this example again to confirm that you understand how to apply the color code given by the first three bands.

The remaining band is called the TOLERANCE band. This indicates the percentage accuracy of the resistor value. Most carbon film resistors have a gold-colored tolerance band, indicating that the actual resistance value is with + or - 5% of the nominal value. Other tolerance colours are:

Tolerance

Color

±1% brown

±2% red

±5% gold

±10% silver

When you want to read off a resistor value, look for the tolerance band, usually gold, and hold the resistor with the tolerance band at its right hand end. Reading resistor values quickly and accurately isn't difficult, but it does take practice!


8.SOFTWARE DISCRIPTION 8.1 KEIL MICROVISION

-An IDE for Microcontrollers

Introduction:

Keil development tools for the 8051 Microcontroller Architecture support every level of software developer from the professional applications engineer to the student just learning about embedded software development.

The industry-standard Keil C Compilers, Macro Assemblers, Debuggers, Real-time Kernels, Single-board Computers, and Emulators support all 8051 derivatives and help you get your projects completed on schedule

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

When starting a new project, simply select the microcontroller you use from the Device Database and the µVision IDE sets all compiler, assembler, linker, and memory options for you.

Numerous example programs are included to help you get started with the most popular embedded 8051 devices.

The Keil µVision Debugger accurately simulates on-chip peripherals (I²C, CAN, UART, SPI, Interrupts, I/O Ports, A/D Converter, D/A Converter, and PWM Modules) of your 8051 device. Simulation helps you understand hardware configurations and avoids time wasted on setup problems. Additionally, with simulation, you can write and test applications before target hardware is available.

When you are ready to begin testing your software application with target hardware, use the MON51, MON390, MONADI, or FlashMON51 Target Monitors, the ISD51 In-System Debugger, or the ULINK USB-JTAG Adapter to download and test program code on your target system.

The µVision3 IDE is a Windows-based software development platform that combines a robust editor, project manager, and make facility. µVision3 integrates all tools including the C compiler, macro assembler, linker/locator, and HEX file generator.


µVision3 helps expedite the development process of your embedded applications by providing the following:

Full-featured source code editor, Device database for configuring the development tool setting, Project manager for creating and maintaining your projects, Integrated make facility for assembling, compiling, and linking your embedded

applications, Dialogs for all development tool settings, True integrated source-level Debugger with high-speed CPU and peripheral

simulator, Advanced GDI interface for software debugging in the target hardware and for

connection to Keil ULINK, Flash programming utility for downloading the application program into Flash

ROM, Links to development tools manuals, device datasheets & user’s guides.

The µVision3 IDE offers numerous features and advantages that help you quickly and successfully develop embedded applications. They are easy to use and are guaranteed to help you achieve your design goals.

The µVision3 IDE and Debugger is the central part of the Keil development tool chain. µVision3 offers a Build Mode and a Debug Mode.

In the µVision3 Build Mode you maintain the project files and generate the application.

In the µVision3 Debug Mode you verify your program either with a powerful CPU and peripheral simulator or with the Keil ULINK USB-JTAG Adapter (or other AGDI drivers) that connect the debugger to the target system. The ULINK allows you also to download your application into Flash ROM of your target system.

ABOUT THE ENVIRONMENT

http://www.keil.com/ulink/

http://www.keil.com/support/man/docs/uv3/uv3_debugging.htm

http://www.keil.com/support/man/docs/uv3/uv3_creating_apps.htm

http://www.keil.com/support/man/docs/uv3/uv3_debugging.htm



The µVision3 screen provides you with a menu bar for command entry, a tool bar where you can rapidly select command buttons, and windows for source files, dialog boxes, and information displays. µVision3 lets you simultaneously open and view multiple source files.µVision3 has two operating modes:

Build Mode: Allows you to translate all the application files and to generate executable programs. The features of the Build Mode are described under Creating Applications.

Debug Mode: Provides you with a powerful debugger for testing your application. The Debug Mode is described in Testing Programs.

In both operating modes you may use the source editor of µVision3 to modify your source code. The Debug mode adds additional windows and stores an own screen layout. The following picture shows a typical configuration of µVision3 in the Debug Mode.

The tabs of the Project Workspace give you access to:

o Files and Groups of the project. o CPU Registers during debugging. o Tool and project specific on-line Books. o Text Templates for often used text blocks. o Function in the project for quick editor navigation.

The tabs of the Output Window provides: Build messages and fast error access; Debug Command input/output console; Find in Files results with quick file access.

The Memory Window gives access to the memory areas in display various formats.

The Watch & Call Stack Window allows you to review and modify program variables and displays the current function call tree.

The Workspace is used for the file editing, disassembly output, and other debug information.

The Peripheral Dialogs help you to review the status of the on-chip peripherals in the microcontroller.

8.2 SOFTWARE DEVELOPMENT CYCLE

http://www.keil.com/support/man/docs/uv3/uv3_5_dbg_watchwin.htm

http://www.keil.com/support/man/docs/uv3/uv3_5_dbg_memwin.htm

http://www.keil.com/support/man/docs/uv3/uv3_4_findinfiles.htm

http://www.keil.com/support/man/docs/uv3/uv3_6_overview.htm

http://www.keil.com/support/man/docs/uv3/uv3_3_buildproject.htm

http://www.keil.com/support/man/docs/uv3/uv3_10_dlg_template.htm

http://www.keil.com/support/man/docs/uv3/uv3_3_bookstab.htm

http://www.keil.com/support/man/docs/uv3/uv3_5_dbg_cpuregs.htm

http://www.keil.com/support/man/docs/uv3/uv3_3_create_file_groups.htm

http://www.keil.com/support/man/docs/uv3/uv3_3_sourcefiles.htm

http://www.keil.com/support/man/docs/uv3/uv3_5_uvision3debugger.htm

http://www.keil.com/support/man/docs/uv3/uv3_3_creatingapps.htm

http://www.keil.com/support/man/docs/uv3/uv3_2_overview.htm


Home » µVision3 Overview » Software Development Cycle

When you use the Keil µVision3, the project development cycle is roughly the same as it is for any other software development project.

1. Create a project, select the target chip from the device database, and configure the tool settings.

2. Create source files in C or assembly. 3. Build your application with the project manager. 4. Correct errors in source files. 5. Test the linked application.

The following block diagram illustrates the complete µVision3 software development cycle. Each component is described below.

µVision3 IDE

The µVision3 IDE combines project management, a rich-featured editor with interactive error correction, option setup, make facility, and on-line help. Use µVision3 to create your source files and organize them into a project that defines your target application. µVision3 automatically compiles, assembles, and links your embedded application and provides a single focal point for your development efforts.

C Compiler & Macro Assembler

Source files are created by the µVision3 IDE and are passed to the C or EC++ Compiler or Macro Assembler. The compiler and assembler process source files and create reloadable object files.

Library Manager

The library manager allows you to create object library from the object files created by the compiler and assembler. Libraries are specially formatted, ordered program collections of object modules that may be used by the linker at a later time. When the linker processes a library, only those object modules in the library that are necessary to create the program are used.

Linker/Locator

The Linker/Locator creates an executable program file using the object modules extracted from libraries and those created by the compiler and assembler. An executable program file (also called absolute object module) contains no reloadable code or data. All code and data reside at fixed memory locations.

http://www.keil.com/support/man/docs/uv3/uv3_overview.htm

http://www.keil.com/support/man/docs/uv3/default.htm


This executable program file may be used:

To program an Flash ROM or other memory devices, With the µVision3 Debugger for simulation and target debugging, With an in-circuit emulator for the program testing.

µVision3 Debugger

The µVision3 symbolic, source-level debugger is ideally suited for fast, reliable program debugging. The debugger includes a high-speed simulator that let you simulate an microcontroller system including on-chip peripherals and external hardware. The µVision3 Debugger provides several ways for you to test your programs on real target hardware.

Use the Keil ULINK USB-JTAG adapter for Flash downloading and software test of your program via on-chip debugging system like the Embedded ICE macro cell that is integrated in many ARM devices.

Use the AGDI interface to attach use the µVision3 Debugger front end with your target system using other debuggers like Monitor, In-System Debugger, or Emulator.

At Keil Software, we are dedicated to provide you with the best embedded development tools and documentation available. If you have suggestions or comments regarding any of the on-line manuals accompanying this product, please contact us. If you think you have discovered a problem with the software, do the following before calling technical support.

1. Read the sections in this manual that pertains to the job or task you are trying to accomplish.

2. Make sure you are using the most current version of the software and utilities. Check www.keil.com/update to make sure that you have the latest software version.

3. Isolate the problem to determine if it is a problem with the assembler, compiler, linker, debugger, or another development tool.

4. Further isolate software problems by reducing your code to a few lines.

If you are still experiencing problems after following these steps, report them to our technical support group. Please include your product serial number and version number. We prefer that you send the problem via email. If you contact us by fax, be sure to include your name and telephone numbers (voice and fax) where we can reach you.

Try to be as detailed as possible when describing the problem you are having. The more descriptive your example, the faster we can find a solution. If you have a single-page code example demonstrating the problem, please email it to us. If possible, make

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sure that your problem can be duplicated with the µVision3 Simulator. Please try to avoid sending complete applications or long listings as this slows down our response to you.

The µVision3 User Interface consists of menus, toolbar buttons, keyboard shortcuts, dialog boxes, and windows that you use as you interact with and manage the various aspects of your embedded project.

The menu bar provides menus for editor operations, project maintenance, development tool option settings, program debugging, external tool control, window selection and manipulation, and on-line help.

The toolbar buttons allow you to rapidly execute µVision3 commands. A Status Bar provides editor and debugger information. The various toolbars and the status bar can be enabled or disabled from the View Menu commands.

Keyboard shortcuts offer quick access to µVision3 commands and may be configured via the menu command Edit – Configuration - Shortcut Key.

The following sections list the µVision3 commands that can be reached by menu commands, toolbar buttons, and keyboard shortcuts. The µVision3 commands are grouped mainly based on the appearance in the menu bar:

File Menu and File Commands Edit Menu and Editor Commands

o Outlining Menu o Advanced Menu o Selecting Text Commands

View Menu Project Menu and Project Commands Debug Menu and Debug Commands Flash Menu Peripherals Menu Tools Menu SVCS Menu Window Menu Help Menu

CREATING APPLICATIONS

Home » Creating Applications

This chapter describes the Build Mode of µVision3 and is grouped into the following sections:

Create a Project: explains the steps required to setup a simple application and to generate HEX output.

http://www.keil.com/support/man/docs/uv3/uv3_ca_createproject.htm


http://www.keil.com/support/man/docs/uv3/uv3_ui_help.htm

http://www.keil.com/support/man/docs/uv3/uv3_ui_window.htm

http://www.keil.com/support/man/docs/uv3/uv3_ui_svcs.htm

http://www.keil.com/support/man/docs/uv3/uv3_ui_tools.htm

http://www.keil.com/support/man/docs/uv3/uv3_ui_peripherals.htm

http://www.keil.com/support/man/docs/uv3/uv3_ui_flash.htm

http://www.keil.com/support/man/docs/uv3/uv3_ui_debug.htm

http://www.keil.com/support/man/docs/uv3/uv3_ui_project.htm

http://www.keil.com/support/man/docs/uv3/uv3_ui_view.htm

http://www.keil.com/support/man/docs/uv3/uv3_ui_seltext.htm

http://www.keil.com/support/man/docs/uv3/uv3_ui_advanced.htm

http://www.keil.com/support/man/docs/uv3/uv3_ui_outline.htm

http://www.keil.com/support/man/docs/uv3/uv3_ui_edit.htm

http://www.keil.com/support/man/docs/uv3/uv3_ui_file.htm

http://www.keil.com/support/man/docs/uv3/uv3_dg_shortkeys.htm

http://www.keil.com/support/man/docs/uv3/uv3_ui_view.htm

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http://www.keil.com/support/man/docs/uv3/uv3_ui_statusbar.htm


Project Target and File Groups: shows how to create application variants and organized the files that belong to a project.

Tips and Tricks: provides information about the advanced features of the µVision3 Project Manager.

CREATE PROJECT

Home » Creating Applications » Create Project

µVision3 is a standard Windows application and started by clicking on the program icon. About the Environment describes the different window areas of µVision3.

µVision3 includes a project manager which makes it easy to design applications for an ARM based microcontroller. You need to perform the following steps to create a new project:

Select the Toolset (only required for ARM Projects). Create Project File and Select CPU. Project Workspace - Books. Create New Source Files. Add Source Files to the Project. Create File Groups. Set Tool Options for Target Hardware. Configure the CPU Startup Code. Build Project and Generate Application Program Code. Create a HEX File for PROM Programming.

The section provides a step-by-step tutorial that shows you how to create a simple µVision3 project.

PROJECT TARGETS AND FILE GROUPS

Home » Creating Applications » Project Targets and File Groups

By using different Project Targets µVision3 lets you create several programs from a single project. You may need one target for testing and another target for a release version of your application. Each target allows individual tool settings within the same project file.

Files Groups let you group associated files together in a project. We have already used file groups in our example to separate the CPU related files from other source files. With these technique it is easily possible to maintain complex projects with several 100 files in µVision3.



http://www.keil.com/support/man/docs/uv3/uv3_3_createhexfile.htm

http://www.keil.com/support/man/docs/uv3/uv3_3_buildproject.htm

http://www.keil.com/support/man/docs/uv3/uv3_3_config_start_code.htm

http://www.keil.com/support/man/docs/uv3/uv3_3_tool_options.htm

http://www.keil.com/support/man/docs/uv3/uv3_3_create_file_groups.htm

http://www.keil.com/support/man/docs/uv3/uv3_3_sourcefiles.htm

http://www.keil.com/support/man/docs/uv3/uv3_3_create%20_source_file.htm

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http://www.keil.com/support/man/docs/uv3/uv3_1_environment.htm



http://www.keil.com/support/man/docs/uv3/uv3_ca_tipsandtricks.htm

http://www.keil.com/support/man/docs/uv3/uv3_ca_projtargfilegr.htm


The dialog Project – Components, Environment, Books... – Project Components allows you to create project targets and file groups. We have already used this dialog to add system configuration files in a file group. An example project structure is shown below.

The Project Workspace shows all groups and the related files. Files are built and linked in the same order as shown in this window. You can move file positions with Drag & Drop. You may select a target or group name and Click to rename it. The local menu opens with a right mouse Click and allows you for each item:

to set tool options to remove the item to add files to a group to open the file.

In the build toolbar you can quickly change the current project target to build.

PROJECT COMPONENTS

Home » Dialogs » Project

You may add, delete, or re-arrange the items with the list box buttons in Project Targets, Groups, and Files.

Project Targets Shows all Project Targets in your project. Project Targets let you create several programs form a single project. You may need one target for testing and another target for a release version of your application.

Groups Shows all File Groups in your current project. File Groups let you group associated files together in a project. This is useful for grouping files into functional blocks or for identifying engineers in your software team.

Files

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Shows all files of the selected File Group.Set as Current Target

Set the selected Project Target as the current target.Add Files

Add files to the selected File Group.

FILE EXTENSIONS Home » Creating Applications » Tips and Tricks » File Extensions

The dialog Project – Components, Environment and Books allows you to set the file extension for the various file types of a project. You can enter several extensions when you separate them by semi-colon. The file extensions are project specific.

Selecting a Generic Device

Under the Generic section in the device database, you will find the following generic devices:

8031 (all Variants) 8032 (all Variants) 8051 (all Variants) 8052 (all Variants) C166 (all Variants) - Supports CPUs with no extended instruction set C167 (all Variants) - Supports CPUs with an extended instruction set ARM7 (all Variants) - Supports ARM7 based microcontrollers

You may select one of these devices and then specify any necessary chip options in the in the Options for Target – Target dialog. For example on-chip memory may be specified as External Memory.





Importing µVision 1 ProjectsHome » Creating Applications » Tips and Tricks » Importing µVision 1 Projects

You can import project files from µVision1 by using the menu item Project - Import µVision1 Project. This starts the following procedure:

1. Create a new µVision project file. It is important that the new µVision2/3 project file is created in the existing µVision1 project folder.

2. Select a CPU from the device database.

3. Select the old µVision1 project file that exists in the project folder.

4. This import the old µVision1 linker settings into the L166 dialogs. However, we recommend that you use the dialog µVision Options for Target – Target to define the memory structure of the target hardware. Once you have done that, you should open the dialog Options for Target – L166 / Lx51 Locate. Enable the option Use Memory Layout from Target and remove the settings for User Classes, User Segments, or User Sections in this dialog.

5. Check carefully if all settings are copied correctly to the new µVision project file.

6. You may now create file groups in the new µVision project. Then you can Drag & Drop files into the new file groups.

DebuggingHome » Debugging

This chapter describes the Debug Mode of µVision3 and shows you how to use the user interface to test a sample program. Also discussed are simulation mode and the different options available for program debugging.

You can use µVision3 Debugger to test the applications you develop. The µVision3 Debugger offers two operating modes that are selected in the Options for

Target – Debug dialog.

Use Simulator configures the µVision3 Debugger as software-only product that simulates most features of a microcontroller without actually having target hardware. You can test and debug your embedded application before the hardware is ready. µVision3 simulates a wide variety of peripherals including the serial port, external I/O, and timers. The peripheral set is selected when you select a CPU from the device database for your target.

Use Advanced GDI drivers, like the ULINK Debugger to interface to your target hardware. For µVision3 various drivers are available that interface to:

o JTAG/OCDS Adapter: which connects to on-chip debugging systems like the ARM Embedded ICE.

o Monitor: that may be integrated with user hardware or is available on many evaluation boards.

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o Emulator: which connects to the CPU pins of the target hardware. o In-System Debugger: which is part of the user application program

and provides basic test functions. o Test Hardware: such as the Infineon Smartcard ROM Monitor RM66P

or the Philips Smarm Box.

Flash ProgrammingHome » Flash Programming

µVision3 integrates Flash Programming Utilities in the project environment. All configurations are saved in context with your current project.

You may use external command-line driven utilities (usually provided by the chip vendor) or the Keil ULINK USB-JTAG Adapter. The Flash Programming Utilities are configured under Project - Options - Utilities.

Flash Programming may be started from the Flash Menu or before starting the µVision3 Debugger when you enable Project - Options - Utilities - Update Target before Debugging.

Measure - Project FileHome » Example Programs » Measure: A Remote Measurement System » Measure

- Project File

The project file for the MEASURE sample program is called Measure.UV2. To load this project file, use Open Project from the Project menu and select Measure.UV2 in the folder ...\ARM\...\Examples\Measure.

The Files page in the Project Workspace shows the source files that compose the MEASURE project. The three application related source files that are located in the Source Files group. The function of the source files is described below. To open a source file, double-click on the filename.

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http://www.keil.com/support/man/docs/uv3/uv3_examples.htm


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Measure’s: contains the main C function for the measurement system and the interrupt routine for timer 0. The main function initializes all peripherals of the ARM and performs command processing for the system. The timer interrupt routine, timer0, manages the real-time clock and the measurement sampling of the system.

MCommand.C: processes the display, time, and interval commands. These functions are called from main. The display command lists the analog values in floating-point format to give a voltage between 0.00V and 5.00V.

GetLine.C: contains the command-line editor for characters received from the serial port.

IRQ.S: is an interface module for the interrupt service routine.

Compiling and Linking MeasureHome » Example Programs » Measure: A Remote Measurement System »

Compiling and Linking Measure

When you are ready to compile and link the MEASURE project, use the Build Target command from the Project menu or the toolbar. µVision3 begins to compile and link the source files in MEASURE and displays a message when the build is finished.

Once the project is built, you are ready to browse the symbol information or begin testing.

Testing MeasureHome » Example Programs » Measure: A Remote Measurement System » Testing

Measure

The MEASURE sample program is designed to accept commands from the on-chip serial port. If you have actual target hardware, you can use a terminal simulation








to communicate with the ARM CPU. If you do not have target hardware, you can use µVision3 to simulate the hardware. You can also use the serial window in µVision3 to provide serial input.Once the MEASURE program is build, you can test it. Use the Start/Stop Debug Session command from the Debug menu to start the µVision3 debugger.

Remote Measurement System Commands

The serial commands that MEASURE supports are listed in the following table. These commands are composed of ASCII text characters.

Command Serial Text Description

Clear C Clears the measurement record buffer.Display D Displays the current time and input values.Time T hh:mm:ss Sets the current time in 24-hour format.

Interval I mm:ss.tttSets the interval time for the measurement samples. The interval time must be between 0:00.001 (for 1ms) and 60:00.000 (for 60 minutes).

Start SStarts the measurement recording. After receiving the start command, MEASURE samples all data inputs at the specified interval.

Read R [count]

Displays the recorded measurements. You may specify the number of most recent samples to display with the read command. If no count is specified, the read command transmits all recorded measurements. You can read measurements on the fly if the interval time is more than 1 second. Otherwise, the recording must be stopped.

Quit Q Quits the measurement recording.

View Program CodeHome » Example Programs » Measure: A Remote Measurement System » View

Program Code

µVision3 lets you view the program code in the Disassembly Window that opens with the View menu or the toolbar button. The Disassembly Window shows intermixed source and assembly lines. You may change the view mode or use other commands from the local menu that opens with the right mouse button.





View Memory ContentsHome » Example Programs » Measure: A Remote Measurement System » View

Memory Contents

µVision3 displays memory in various formats. The Memory Window opens via the View menu or the toolbar button. You can enter the address of four different memory areas in the pages. The local menu allows you to modify the memory contents or select different output formats.





Program ExecutionHome » Example Programs » Measure: A Remote Measurement System » Program

Execution

Before you begin simulating MEASURE, open the Serial Window #1 that displays the serial output with the View menu or the Debug toolbar. You may disable other windows if your screen is not large enough.

You can use the Step toolbar buttons on assembler instructions or source code lines. If the Disassembly Window is active, you single step at assembly instruction basis. If an editor window with source code is active, you single step at source code level.

Call StackHome » Example Programs » Measure: A Remote Measurement System » Call

Stack

µVision3 internally tracks function nesting as the program executes. The Call Stack page of the Watch Window shows the current function nesting. A double click on a line displays the source code that called the selected function.

Breakpoints DialogHome » Example Programs » Measure: A Remote Measurement System »

Breakpoints Dialog











µVision3 also supports complex breakpoints as discussed on page 109. You may want to halt program execution when a variable contains a certain value. The example shows how to stop when the value 3 is written to current.time.sec.

Open the Breakpoints dialog from the Debug menu. Enter as expression current.time.sec==3. Select the Write check box (this option specifies that the break condition is tested only when the expression is written to). Click on the Define button to set the breakpoint.

To test the breakpoint condition perform the following steps:

Symbol Description

Reset CPU.If program execution is halted begin executing the MEASURE program.

After a few seconds, µVision3 halts execution. The program counter line in the debug window marks the line in which the breakpoint occurred.

Using Peripheral Dialog BoxesµVision3 provides dialogs for: I/O Ports, Interrupts, Timers, A/D Converter, Serial Ports, and chip-specific peripherals. These dialogs can be opened from the Debug menu. For the MEASURE application you may open I/O Ports:Port2 and A/D Converter.

Each of these dialogs lists the related SFR symbols and shows the current status of the peripherals. To change the inputs, change the values of the Pins or Analog Input Channels.

Using VTREG SymbolsIn the Command page of the Output Window, you may make

assignments to the VTREG symbols just like variables and registers. For example:PORT2=0xDA00 set digital input PORT2 to 0xDA00.AIN1=3.3 set analog input AIN1 to 3.3 volts.Using User and Signal Functions

You may combine the use of VTREG symbols defined by the CPU driver and µVision3 user and signal functions to create a sophisticated method of providing external input to your target programs. The Analog Example shows a signal function that provides input to AIN0.

9.CODING

http://www.keil.com/support/man/docs/uv3/uv3_df_signalfunctions.htm


Program written in C language

#include<stdio.h>#include<reg51.h>void delay(into);void medley(void);sit sen1=P1^0;sit sen2=P1^1;sit buzz=P1^3;sit sig1=P1^4;sit sig2=P1^5;sit laser=P1 ^6;void close();void open();void buzzer();into m=10000;void main(){

P0=P2=P3=0x00;P1=0xff;buzzer();sig1=0x00; //train stop/road gosig2=0x01;open();for(;;){

if(sen1==0x00){

sig1=0x01; sig2=0x00; //train go/road stop buzzer();close();medley();while(sen2==0x01){}while(sen2==0x00){}sig1=0x00; sig2=0x01; //train stop/road go buzzer();open();

}if(sen2==0x00){

sig1=0x01; sig2=0x00; //train go/road stop buzzer();close();medley();while(sen1==0x01){}while(sen1==0x00){}


sig1=0x00; sig2=0x01; //train stop/road go buzzer();open();

}}

}void medley(void){

into l=0;for(l=0;l<=200;l++){

TMOD=0x10;TL1=0xfe;TH1=0xa5;TR1=1;while(TF1==0){

if(laser==0x00){

sig1=0x00; sig2=0x01; //train stop/road go buzzer();open();

while(laser==0x00){} sig1=0x01; sig2=0x00; //train go/road stop buzzer();close();

} }TR1=0;TF1=0;

}}void buzzer(){

into y;for(y=0;y<=8;y++){

buzz=0x01;deley(15000);buzz=0x00;deley(15000);

}}void open(){

P2=0x11;deley(m);P2=0x33;deley(m);


P2=0x22;deley(m);P2=0x66;deley(m);P2=0x44;deley(m);P2=0xcc;deley(m);P2=0x88;deley(m);P2=0x99;deley(m);

P2=0x11;deley(m);P2=0x33;deley(m);P2=0x22;deley(m);P2=0x66;deley(m);P2=0x44;deley(m);P2=0xcc;deley(m);P2=0x88;deley(m);P2=0x99;deley(m);

}void close(){

P2=0x99;deley(m);P2=0x88;deley(m);P2=0xcc;deley(m);P2=0x44;deley(m);P2=0x66;deley(m);P2=0x22;deley(m);P2=0x33;deley(m);P2=0x11;deley(m);

P2=0x99;deley(m);P2=0x88;deley(m);P2=0xcc;deley(m);P2=0x44;deley(m);P2=0x66;deley(m);P2=0x22;deley(m);P2=0x33;deley(m);P2=0x11;deley(m);

}void delay(k){

into i=0;for(i=0;i<=kid++){}

}

PROGRAM HEX CODE:


:04022E00020C271087:10014B00E4F5B0F5A0F5807590FF1201E4C294D2EE:10015B009512008F2090191201E01200ED120199F7:10016B002091FD3091FDC294D2951201E412008FC3:10017B002091E11201E01200ED1201992090FD3067:0E018B0090FDC294D2951201E412008F80C63E:10019900E4F508F509F508F509758910758BFE75FB:1001A9008DA5D28E208F182096FAC294D29512016D:1001B900E412008F3096FD1201E01200ED80E5C2D5:1001C9008EC28F0509E50970020508D394C8E508B0:0601D9006480948040C325:0101DF0022FD:0401E000D294C2955E:1001E400E4F50AF50BD2937F987E3A120216C29375:1001F4007F987E3A120216050BE50B7002050AD3AE:0A0204009408E50A6480948040DB52:01020E0022CD:10008F0075A01112021212020F75A0221202127520:10009F00A06612021275A04412021275A0CC1202B1:1000AF001275A08812021275A09912021275A01172:1000BF0012021212020F75A02212021275A06612FE:1000CF00021275A04412021275A0CC12021275A072:0E00DF008812021275A099AF0DAE0C02021627:1000ED0075A09912021275A08812021275A0CC1279:1000FD00021275A04412021275A06612021275A0AA:10010D002212021212020F75A01112021275A0997D:10011D0012021275A08812021275A0CC120212756D:10012D00A04412021275A06612021275A0221202CC:0E013D001212020F75A011AF0DAE0C020216C9:07020F0075A033AF0DAE0C2A:10021600E4FDFCD3ED9FEE6480F8EC648098500713:070226000DBD00010C80EC8E:01022D0022AE:03000000020003F8:0C000300787FE4F6D8FD75810D02004AFC:10000F0002014BE493A3F8E493A34003F68001F2BB:10001F0008DFF48029E493A3F85407240CC8C333F2:10002F00C4540F4420C8834004F456800146F6DFC1:10003F00E4800B010204081020408090022EE47E21:10004F00019360BCA3FF543F30E509541FFEE493B6:10005F00A360010ECF54C025E060A840B8E493A37D:10006F00FAE493A3F8E493A3C8C582C8CAC583CAA8:10007F00F0A3C8C582C8CAC583CADFE9DEE780BE60:0102320000CB:00000001F


10. CONCLUSIONS:

Hence the Unmanned railway gates operate according to the data input from sensors to microcontroller. First an alarm is triggered and then the gate is operated.

Specifications:

Mechanical gate arrangement Atmel 89C51 an 8051 family microcontroller SN7404 for microcontroller interfacing. IR sensors for sensing train Geared motor to operate gates ULN 2803 for driving Geared motor

11. BIBLIOGRAPHY


Name of the sites:

1. www.mitel.databook.com

2. www.atmel.databook.com

3. www.franklin.com

4. www.keil.com

References:

www.8052.com/tutorial.phtml 8051 microcontroller by Kenneth J. Ayala www.electronicsforu.com/electronicsforu/articles/hits.asp?id=1431 Programming Embedded Systems: With C and GNU Development Tools

by Michael Barr Basic electronics By: GROB Practical transistor circuit design and analysis By: GERALD E. WILLIAMS Sensor - Electronic circuit guide book – Volume – 1 By: JOSEPH J.CARR Programming and Customizing the 8051 Micro-controller By: Mike Prado The concepts and Features of Micro-controllers - By: Raj Kamala The 8051 Micro-controller Architecture, programming & Applications

By: Kenneth J. Ayala CMOS/TTL IC Data Manuals

http://www.keil.com/

http://www.franklin.com/

http://www.atmel.databook.com/

http://www.mitel.databook.com/

automatic railway crossing using micro controller report

Engineering

Transcript of automatic railway crossing using micro controller report