Car Speed REPORT

7/29/2019 Car Speed REPORT

1/70

CONTENTS

1. SYNOPSIS

2. INTRODUCTION3. BLOCK DIAGRAM

4. BLOCK DIAGRAM DESCRIPTION

5. CIRCUIT DIAGRAM

6. IC DETAILS

7. PROGRAM

8. COMPONENT DETAILS

9. POWER SUPPTY

10.ADVANTAGES

11.APPLICATION

12.FUTURE MODIFICATION

13.CONCLUSION

14.BIBLIOGRAPHY


2/70

SYNOPSIS

We have two stages for this project. One is a data transmitter section whichencodes a data and transmits it using RF modules. This data is encoded by a

microcontroller by our program.

On the other end there is a receiver stage which receives the transmitted data

by a RF receiver module and acts as a trigger signal for a microcontroller to

change the speed of a dc motor driven by the microcontroller and the driver

components of the circuit.

The microcontroller is programmed for PWM process to increase or

decrease the speed of the dc motor when it receives the data signal for

increment or decrement.

That is, on receipt of the increment data the ON time of the PWM

waveform is increased and during the slow down process the OFF time of

the PWM waveform is increased by our program.

ATMEL 89c51 is used as our microcontroller which exists from the family

of INTEL 8051 and it is communicated in ASSEMBLY language.

The block diagram gives a brief explanation of the project.


3/70

INTRODUCTION

In school areas we need some kind of automation to bring down the speed

of the vehicles. To prove this concept we have to design a data transmitter

which transmits a data continuously & this transmitter is kept near the

school areas at least 100 meters before. The vehicle is designed with a

microcontroller based data receiver which enables a voice circuit to warn the

driver that he is entering the school area & he will be slowed down

automatically. Then the microcontroller is programmed to slow down the

vehicle. In real time applications the carburetor will be set to slow speed

setup by controlling the air input by means of a solenoid valve. In this case

the manual raising will be disabled. But in our circuit we program the

microcontroller to generate a PWM to slow down the motor as per our

circuit. That is to say that the off time of the motor is increased & the on

time is reduced to predetermined speed. The transmitter stage in our circuit

sends a 8 bit digital data continuously using a RF module TX434 with an

encoder HT12E & the receiver module has a RF receiver module RX434

with a decoder. Both the stages have been interfaced with a microcontroller

for data processing. The receiver end microcontroller has a data base 8bit

value, which would be compared with the transmitted 8 bit value, when boththe data values happen to be same, the microcontroller will start its

automation with voice warning & PWM motor control. Atmel 89c51 is used

as our microcontroller which exists from the family of INTEL 8051 & it is

programmed in assembly language.


4/70

BLOCK DIAGRAM

TRANSMITTER:


5/70

RECEIVER:


6/70

BLOCK DIAGRAM DESCRIPTION:

ENCODER:

An encoder is a device used to change a signal (such as a bitstream) or data into a code. The code may serve any of a number of purposes

such as compressing information for transmission or storage, encrypting or

adding redundancies to the input code, or translating from one code to

another. In digital electronics this would mean that a decoder is a multiple-

input, multiple-output logic circuit (2 n-n).

18 PIN DIP

Operating voltage:2.4v~12v

Low power and high noise immunity COMS technology

Low standby current and minimum transmission word


7/70

Built-in oscillator needs only 5% resistor

Easy interface with and RF or an infrared transmission medium .

RF TRANSMITTER:

The design of RF transmitter for wireless applications entails many

challenges at both architecture and circuit levels. The number of off-chip

components, the restrictions on unwanted emissions and the trade-offs

between the output power, the efficiency, and the required linearly directly

impact the choice of the transmitter topology and the implementation of

each circuit block. Furthermore, the disturbance of the transceivers

oscillators and receive path by the transmit path influence planning and the

limits the level of integration.

TRANSMITTER MODULE:


8/70

Functional block of TX section where 1,2,3,4 are the pins

1- Antenna

2- Data input3- Ground

4- VCC

In this transmitting section the 1 st pin is the antenna pin where we

can able to fix the antenna for transmitting the data radio frequency, the 2 nd

pin is the data input pin in which the encoder is given; the 3 rd pin is ground

and the 4 th pin is the VCC which is given to operate the transmitter section.

RECIVER SECTION:

RF RECIVER:

A low voltage silicon bipolar RF (radio frequency) receiver front

end includes a low noise preamplifier and double-balanced mixer. The

receiver incorporates monolithic microstrip transformers for significant

improvements in performance compared with silicon broadband designs.

Reactive feedback and coupling elements are used in place of resistors to

lower the front end noise figure through the reduction of resistor thermalnoise, and this also both circuits to operate at supply voltages below 2volts.

RF RECEIVER MODULE:


9/70

Functional block of Rx section where 1,2,3,4 are the pins

1- Antenna2- Data input

3- Ground

4- VCC

In this receiving section the 1 st pin is the antenna pin where we can

able to fix the antenna for receiving the data radio frequency, the 2 nd pin is

the data input pin in which the decoder is given; the 3 rd pin is ground and the

4 th pin is the VCC. This is given to operate the receiver section.


10/70

DECODER:

A decoder is a device which does the reverse of an encoder, un doing the

encoding so that the original information can be retrieved. The same methodused to encode is usually just reversed in order to decode. In digital

electronics this would mean that a decoder is a multiple-input, multiple-

output logic circuit (n-2 n).

HD12D (Holteks decoder) Decoder:

Operating voltage: 2.4V~12V Low power and high noise immunity CMOS technology

Low standby current

Capable of decoding 12 bits of information

Binary address setting

Received codes are checked 3 times

Address/Data number combination HT12D: 8 address bits and 4 data bits

HT12F: 12 address bits only

Built-in oscillator needs only 5% resistor

Valid transmission indicator

Easy interface with an RF or an infrared transmission medium

Minimal external components 18-pin DIP, 20-pin SOP package.


11/70

ALERT SYSTEM:

In this system has one alert. This is used to give the alert to the

driver. In here we use the 4ohms speaker. This is producing the sound.

CIRCUIT DIAGRAM:

TRANSMITTER:


12/70


13/70

RECEIVER:


14/70

IC DETAILS:

ATMEL89C51 MICROCONTROLLER:

FEATURES :

Compatible with MCS-51 TM products.


15/70

4K BYTES of in system programmable flash memory

Endurance: 1000 write/erase cycles

Fully static operation: 0 HZ to 24 MHz

Three-level program memory lock

128* 8-bit internal RAM

32 programmable I/O lines

Two 16-bit timer/counters

Six interrupt sources

Programmable serial channel

Low-power idle and power-down modes

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). 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


16/70

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. The AT89C51 provides the following standard features:4K bytes of Flash, 128 bytes of RAM, 32 I/O lines, two 16-

bittimer/counters, five vector two-level interrupt architecture, a full duplex

serial port, and on-chip oscillator and clock circuitry. In addition, the

AT89C51 is designed with static logic for operation down to zero frequency

and supports two software selectable power saving modes. The Idle Mode

stops the CPU while allowing the RAM, timer/counters, serial port and

interrupt system to continue functioning. The Power-down Mode saves the

RAM contents but freezes the oscillator disabling all other chip functions

until the next hardware reset.

BLOCK DIAGRAM:


17/70

PIN DIAGRAM:


18/70

PIN DESCRIPTION:

VCC


19/70

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 pullups. Port 0 also

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

bytes during program verification. External pullups are required during

program Verification.

PORT 1

Port 1 is an 8-bit bi-directional I/O port with internal pullups. The Port 1

output buffers can sink/source four TTL inputs. When 1s are written to Port

1 pins they are pulled high by the internal pullups and can be used as inputs.

As inputs, Port 1 pins that are externally being pulled low will source current(IIL) because of the internal pullups. Port 1 also receives the low-order

address bytes during Flash programming and verification.

PORT 2


20/70



2 pins they are pulled high by the internal pullups and can be used as inputs.As inputs, Port 2 pins that are externally being pulled low will source current

(IIL) because of the internal pullups. Port 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



3 pins they are pulled high by the internal pullups and can be used as inputs.

As inputs, Port 3 pins that are externally being pulled low will source current

(IIL) because of the pullups. Port 3 also serves the functions of various

special features of the AT89C51 as listed below:


21/70

Port 3 also receives some control signals for Flash programming andverification.

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


22/70

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 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


23/70

Output from the inverting oscillator amplifier.

O SCILLATOR C HARACTERISTICS

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.

I DLE M ODE

In idle mode, the CPU puts itself to sleep while all the on chip peripherals

remain active. The mode is invoked by software. The content of the on-chip

RAM and all the special functions registers remain unchanged during this

mode. The idle mode can be terminated by any enabled interrupt or by a

hardware reset. It should be noted that when idle is terminated by a hard

ware reset, the device normally resumes program execution, from where it

left off, up to two machine cycles before the internal reset algorithm takescontrol. On-chip hardware inhibits access to internal RAM in this event, but

access to the port pins is not inhibited. To eliminate the possibility of an

unexpected write to a port pin when Idle is terminated by reset, the


24/70

instruction following the one that invokes Idle should not be one that writes

to a port pin or to external memory.

P OWER -DOWN M ODE


25/70

In the power-down mode, the oscillator is stopped, and the instruction that

invokes power-down is the last instruction executed. The on-chip RAM and

Special Function Registers retain their values until the power-down mode isterminated. The only exit from power-down is a hardware reset. Reset

redefines the SFRs but does not change the on-chip RAM. The reset should

not be activated before VCC is restored to its normal operating level and

must be held active long enough to allow the oscillator to restart and

stabilize.

P ROGRAM M EMORY L OCK B ITS

On the chip are three lock bits which can be left unprogrammed (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.

P ROGRAMMING THE F LASH

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 users


26/70

system, while the high-voltage programming mode is compatible with

conventional third-party Flash or EPROM programmers. The AT89C51 is

shipped with either the high-voltage or low-voltage programming mode

enabled. The respective top-side marking and device signature codes arelisted in the following table.

The AT89C51 code memory array is programmed byte-by byte in either programming mode. To program any nonblank byte in the on-chip FlashMemory, the entire memory must be erased using the Chip Erase Mode.

P ROGRAMMING ALGORITHM :

Before programming the AT89C51, the address, data and control signals

should be set up according to the Flash programming mode table and Figure

3 and Figure 4. To program the AT89C51, take the following steps.

1. Input the desired memory location on the address lines.

2. Input the appropriate data byte on the data lines.

3. Activate the correct combination of control signals.

4. Raise EA/VPP to 12V for the high-voltage programming mode.


27/70

5. Pulse ALE/PROG once to program a byte in the Flash array or the lock

bits. The byte-write cycle is self-timed and typically takes no more than 1.5

ms. Repeat steps 1 through 5, changing the address and data for the entire

array or until the end of the object file is reached.


28/70


29/70

DATA P OLLING :

The AT89C51 features Data Polling to indicate the end of a write cycle.

During a write cycle, an attempted read of the last byte written will result inthe complement of the written datum on PO.7. Once the write cycle has been

completed, true data are valid on all outputs, and the next cycle may begin.

Data Polling may begin any time after a write cycle has been initiated.

R EADY /B USY :

The progress of byte programming can also be monitored by the RDY/BSY

output signal. P3.4 is pulled low after ALE goes high during programming

to indicate BUSY. P3.4 is pulled high again when programming is done to

indicate READY.

PROGRAMS VERIFY:

If lock bits LB1 and LB2 have not been programmed, the programmed code

data can be read back via the address and data lines for verification. The lock

bits cannot be verified directly. Verification of the lock bits is achieved by

observing that their features are enabled.

C HIP E RASE :

The entire Flash array is erased electrically by using the proper combination

of control signals and by holding ALE/PROG low for 10 ms. The code array


30/70

is written with all 1s. The chip erase operation must be executed before

the code memory can be re-programmed.

R EADING THE S IGNATURE 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

P ROGRAMMING 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.


31/70

APR9600:

PINDIAGRAM:


32/70

PIN DESCRIPTION:

Pin-out of the APR9600 is given in Figure 1. A typical

connection of the chip is given in Figure 2 (This is the circuit diagram of themodule). Pin functions of the IC are given in Table 1. During sound

recording, sound is picked up by the microphone. A microphone pre-

amplifier amplifies the voltage signal from the microphone. An AGC circuit

is included in the pre-amplifier, the extent of which is controlled by an

external capacitor and resistor. If the voltage level of a sound signal is

around 100 mV peak to- peak, the signal can be fed directly into the IC

through ANA IN pin (pin 20). The sound signal passes through a filter and a

sampling and hold circuit. The

Analogue voltage is then written into non-volatile flash analogue RAMs. It

has a 28 pin DIP package. Supply voltage is between 4.5V to 6.5V. During

recording and replaying, current consumption is 25 mA. In idle mode, the

current drops to 1 mA. During sound replaying, the ICs control circuit reads

analogue data from flash RAMs. The signal then passes through a low-pass

filter, a power amplifier and output to an 8 to 16 Ohm speaker. There is

different sound recording and replaying modes (see Table 2). These modes

are selected using MSEL1 (Pin 24), MSEL2 (Pin 25) and M8 (Pin 9). M1

to M7 keys have different functions in different modes.


33/70


34/70

ULN2003:


35/70

DESCRIPTION:

The ULN2003 is a monolithic high voltage and high current Darlington

transistor arrays. It consists of seven NPN darlington pairs that feature high-

voltage outputs with common-cathode clamp diode for switching inductive

loads. The collector-current rating of a single darlington pair is 500mA. The

darlington pairs may be paralleled for higher current capability. Applications

include relay drivers, hammer drivers, lampdrivers, display drivers (LED gas

discharge), line drivers, and logic buffers. The ULN2003 has a 2.7kW series base resistor for each darlington pair for operation directly with TTL or 5V

CMOS devices.

500mA rated collector current(Single output)

High-voltage outputs: 50V Inputs compatible with various types of logic.

Relay driver application


36/70

LM7805:

DESCRIPTION :

The LM7805 monolithic 3-terminal positive voltage regulators employinternal current-limiting, thermal shutdown and safe-area compensation,

making them essentially indestructible. If adequate heat sinking is provided,

they can deliver over 1.0A output current. They are intended as fixed voltage

regulators in a wide range of applications including local (on-card)

regulation for elimination of noise and distribution problems associated with

single-point regulation. In addition to use as fixed voltage regulators, these

devices can be used with external components to obtain adjustable output

voltages and currents. Considerable effort was expended to make the entire

series of regulators easy to use and minimize the number of external

components. It is not necessary to bypass the output, although this does

improve transient response. Input bypassing is needed only if the regulator is

located far from the filter capacitor of the power supply. The 5V, 12V, and

15V regulator options are available in the steel TO-3 power package. The

LM7805 series is available in the TO-220 plastic power package, and the

LM7805 is available in the SOT-223 package, as well as the LM340-5.0 and

LM340-12 in the surface-mount TO-263 packages.


37/70

EATURES :

Complete specifications at 1A load

Output voltage tolerances of 2% at Tj = 25C and 4%

over the temperature range (LM340A)

Line regulation of 0.01% of VOUT/V of VIN at 1A load

(LM340A)

Load regulation of 0.3% of VOUT/A (LM340A)

Internal thermal overload protection

Internal short-circuit current limit

Output transistor safe area protection

P+ Product Enhancement tested


38/70

T YPICAL APPLICATIONS

F IXED O UTPUT R EGULATOR ADJUSTABLE O UTPUT R EGULATOR

Required if the regulator is located far from the power supply filter.

Although no output capacitor is needed for stability, it does help

transient

Response. (If needed, use 0.1 F, ceramic disc).

LM386:

DESCRIPTION :

The LM386 is a power amplifier designed for use in low voltage consumer

applications. The gain is internally set to 20 to keep external part count low,

but the addition of an external resistor and capacitor between pins 1 and 8

will increase the gain to any value from 20 to 200. The inputs are groundreferenced while the output automatically biases to one-half the supply

voltage. The quiescent power drain is only 24 milliwatts when operating

from a 6 volt supply, making the LM386 ideal for battery operation.

F EATURES

Battery operation

Minimum external parts

Wide supply voltage range: 4V12V or 5V18V

Low quiescent current drain: 4mA

Voltage gains from 20 to 200


39/70

Ground referenced input

Self-centering output quiescent voltage

Low distortion: 0.2% (AV = 20, VS = 6V, RL = 8W, PO =

125mW, f = 1kHz) Available in 8 pin MSOP package


40/70

ULN2003:

LOGIC DIAGRAM:


41/70

SCHEMATIC (EACH DARLINGTON PAIR):

DESCRIPTION:

The ULN2003 is a monolithic high voltage and high current Darlington

transistor arrays. It consists of seven NPN darlington pairs that feature high-


42/70

voltage outputs with common-cathode clamp diode for switching inductive

loads. The collector-current rating of a single darlington pair is 500mA. The

darlington pairs may be paralleled for higher current capability. Applications

include relay drivers, hammer drivers, lamp drivers, display drivers (LEDgas discharge), line drivers, and logic buffers. The ULN2003 has a 2.7kW

series base resistor for each darlington pair for operation directly with TTL

or 5V CMOS devices.

500mA rated collector current(Single output) High-voltage outputs: 50V

Inputs compatible with various types of logic.

Relay driver application

CRYSTAL OSILLATOR:

A crystal oscillator is an electronic circuit that uses the mechanical

resonance of a vibrating crystal of piezoelectric material to create an

electrical signal with a very precise frequency . This frequency is commonly

used to keep track of time (as in quartz wristwatches ), to provide a stable

clock signal for digital integrated circuits , and to stabilize frequencies for

radio transmitters and receivers . The most common type of piezoelectricresonator used is the quartz crystal , so oscillator circuits designed around

them were called "crystal oscillators".
http://en.wikipedia.org/wiki/Electronic_circuithttp://en.wikipedia.org/wiki/Resonancehttp://en.wikipedia.org/wiki/Crystalhttp://en.wikipedia.org/wiki/Piezoelectricity#Materialshttp://en.wikipedia.org/wiki/Frequencyhttp://en.wikipedia.org/wiki/Quartz_clockhttp://en.wikipedia.org/wiki/Clock_signalhttp://en.wikipedia.org/wiki/Digitalhttp://en.wikipedia.org/wiki/Integrated_circuitshttp://en.wikipedia.org/wiki/Radio_transmitterhttp://en.wikipedia.org/wiki/Radio_receiverhttp://en.wikipedia.org/wiki/Quartz_crystalhttp://en.wikipedia.org/wiki/Electronic_circuithttp://en.wikipedia.org/wiki/Resonancehttp://en.wikipedia.org/wiki/Crystalhttp://en.wikipedia.org/wiki/Piezoelectricity#Materialshttp://en.wikipedia.org/wiki/Frequencyhttp://en.wikipedia.org/wiki/Quartz_clockhttp://en.wikipedia.org/wiki/Clock_signalhttp://en.wikipedia.org/wiki/Digitalhttp://en.wikipedia.org/wiki/Integrated_circuitshttp://en.wikipedia.org/wiki/Radio_transmitterhttp://en.wikipedia.org/wiki/Radio_receiverhttp://en.wikipedia.org/wiki/Quartz_crystal


43/70

Quartz crystals are manufactured for frequencies from a few tens of

kilohertz to tens of megahertz. More than two billion (210 9) crystals are

manufactured annually. Most are small devices for consumer devices such

as wristwatches , clocks , radios , computers , and cell phones . Quartz crystalsare also found inside test and measurement equipment, such as counters,

signal generators , and oscilloscopes .

RESISTOR:

Resistors restrict the flow of electric current, for example a resistor is placed

in series with a light-emitting diode (LED) to limit the current passingthrough the LED.

RESISTOR SYMPOL:

EXAMPLE:
http://en.wikipedia.org/wiki/Kilohertzhttp://en.wikipedia.org/wiki/Wristwatchhttp://en.wikipedia.org/wiki/Clockhttp://en.wikipedia.org/wiki/Radiohttp://en.wikipedia.org/wiki/Computerhttp://en.wikipedia.org/wiki/Cellphonehttp://en.wikipedia.org/wiki/Signal_generatorhttp://en.wikipedia.org/wiki/Oscilloscopehttp://en.wikipedia.org/wiki/Kilohertzhttp://en.wikipedia.org/wiki/Wristwatchhttp://en.wikipedia.org/wiki/Clockhttp://en.wikipedia.org/wiki/Radiohttp://en.wikipedia.org/wiki/Computerhttp://en.wikipedia.org/wiki/Cellphonehttp://en.wikipedia.org/wiki/Signal_generatorhttp://en.wikipedia.org/wiki/Oscilloscope


44/70

Small value resistors (less than 10 ohm)

The standard colour code cannot show values of less than 10 . To show

these small values two special colours are used for the third band : gold

which means 0.1 and silver which means 0.01. The first and second

bands represent the digits as normal.

EXAMPLE:

Red, violet, gold bands represent 27 0.1 = 2.7

green, blue, silver bands represent 56 0.01 = 0.56

Tolerance of resistors (fourth band of colour code)

The tolerance of a resistor is shown by the fourth band of the colour code.

Tolerance is the precision of the resistor and it is given as a percentage. For

example a 390 resistor with a tolerance of 10% will have a value within

10% of 390 , between 390 - 39 = 351 and 390 + 39 = 429 (39 is 10% of

390).

A special colour code is used for the fourth band tolerance:silver 10%, gold 5%, red 2%, brown 1%.If no fourth band is shown the tolerance is 20%.

Tolerance may be ignored for almost all circuits because precise resistor values are rarely required.


45/70

RESISTOR COLOR CODE:

CAPACITOR

A capacitor or condenser is a passive electronic component consisting of a

pair of conductors separated by a dielectric. When a voltage potential

difference exists between the conductors, an electric field is present in thedielectric. This field stores energy and produces a mechanical force between

the plates. The effect is greatest between wide, flat, parallel, narrowly

separated conductors.

The Resistor Color Code

Color Number

Black 0

Brown 1Red 2

Orange 3

Yellow 4

Green 5

Blue 6

Violet 7

Grey 8

White 9


46/70

An ideal capacitor is characterized by a single constant value, capacitance,

which is measured in farads. This is the ratio of the electric charge on each

conductor to the potential difference between them. In practice, the dielectric

between the plates passes a small amount of leakage current. The conductorsand leads introduce an equivalent series resistance and the dielectric has an

electric field strength limit resulting in a breakdown voltage.

The properties of capacitors in a circuit may determine the

resonant frequency and quality factor of a resonant circuit, power dissipation

and operating frequency in a digital logic circuit, energy capacity in a high-

power system, and many other important aspects. A capacitor consists of

two conductors separated by a non-conductive region. The non-conductive

substance is called the dielectric medium, although this may also mean a

vacuum or a semiconductor depletion region chemically identical to the

conductors. A capacitor is assumed to be self-contained and isolated, with

no net electric charge and no influence from an external electric field. The

conductors thus contain equal and opposite charges on their facing surfaces,

and the dielectric contains an electric field. The capacitor is a reasonably

general model for electric fields within electric circuits.

ELECTROLYTIC CAPACITOR:

An electrolytic capacitor is a type of capacitor that uses an ionic conducting

liquid as one of its plates. Typically, this is all a lies with a larger

capacitance per unit volume than other types; they are 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. They are also widely


47/70

used as coupling capacitors in circuits where AC should be conducted but

DC should not. Electrolytic capacitors can have a very high capacitance,

allowing filters made with them to have very low corner frequencies.

CERAMIC CAPACITOR:

Ceramic capacitors are a two-terminal, non-polar device. The classical

ceramic capacitor is the disc capacitor. Ceramic disc capacitors are in

widespread use in electronic equipment, providing high capacity & small

size at low price compared to other low value capacitor types. Ceramic

capacitors come in various shapes and styles. The ceramic capacitors come

in various shapes and styles.

CAPACITOR SYMBOL:

EXAMPLES:


48/70

DIODE:

Diodes have two active electrodes between which the signal of

interest may flow, and most are used for their unidirectional electric current

property.

The directionality of current flow most diodes exhibit is sometimes

generically called the rectifying property. The most common function of a

diode is to allow an electric current to pass in one direction (called the

forward biased condition) and to block the current in the opposite direction(the reverse biased condition). Thus, the diode can be through of as an

electronic version of a check value.

Real diodes do not display such a perfect on-off directionality but

have a more complex non-linear electrical characteristic, which depends on

the particular type of diode technology. Diodes also have many other

functions in which they are not designed to operate in this on-off manner.

Today the most common diodes are made from semiconductor materials

such as silicon or germanium.

DIODE SYMBOLS:


49/70

EXAMPLES:

RELAY

An electric current through a conductor will produce a magnetic field

at right angles to the direction of electron flow. If that conductor is wrappedinto a coil shape, the magnetic field produced will be oriented along the

length of the coil. The greater the current, the greater the strength of the

magnetic field, all other factors being equal.

Inductors react again changes in current because of the energy stored

in this magnetic field. When we construct a transformer from two inductor coils around a common iron core, we use this field to transfer energy from

one coil to the other. However, there are simpler and more direct uses for

electromagnets fields than the applications weve seen with inductors and

transformers. The magnetic field produced by a coil of current-carrying wire


50/70

can be used to exert a mechanical force on any magnetic object, just as we

can use a permanent magnet to attract magnetic objects, expect that this

magnet (formed by the coil) can be turned on or off by switching the current

on or off through the coil.If we place a magnetic object near such a coil for the purpose of

making that object move when we energize the coil with electric current, we

have what is called a solenoid. The movable magnetic object is called an

armature, and most armatures can be moved with either direct current (DC)

or alternating current (AC) energizing the coil. The polarity of the magnetic

field is irrelevant for the purpose of attracting an iron armature. Solenoids

can be used to electrically open door latches, open or shut values, move

robotic limbs, and even actuate electric switch mechanisms. However, if a

solenoid is used to actuate a set of switch contacts, we have a device so

useful it deserves its own name: the relay .

POWER SUPPLY:

Power supply for the complete unit can be derived from the mains using a

step-down transformer of 230V AC primary to 12V-0-12V, 500mA

secondary. A full-wave rectifier followed by a capacitor filters the output

voltage and feeds the following 9-volt regulator whose output is used to the

power supply requirement of IR receiver, melody generator and counter

modules. It is also used to provide input to a 6-volt regulator IC used for feeding the transmitter circuit.


51/70

RECTIFIER:

There are several ways of connecting diodes to make a

rectifier to convert AC to DC. The bridge rectifier is the most

important and it produces full-wave varying DC. A full-wave rectifier

can also be made from just two diodes if a centre-tap transformer is

used, but this method is rarely used now that diodes are cheaper. A

single diode can be used as a rectifier but it only uses the positive (+)parts of the AC wave to produce half-wave varying DC.

B RIDGE RECTIFIER

A bridge rectifier can be made using four individual diodes, but it is

also available in special packages containing the four diodes

required. It is called a full-wave rectifier because it uses the entire AC

wave (both positive and negative sections). 1.4V is used up in the

bridge rectifier because each diode uses 0.7V when conducting and

there are always two diodes conducting, as shown in the diagram

below. Bridge rectifiers are rated by the maximum current they can
http://www.kpsec.freeuk.com/powersup.htm#bridgerectifier%23bridgerectifierhttp://www.kpsec.freeuk.com/powersup.htm#singlediode%23singlediodehttp://www.kpsec.freeuk.com/powersup.htm#bridgerectifier%23bridgerectifierhttp://www.kpsec.freeuk.com/powersup.htm#singlediode%23singlediode


52/70

pass and the maximum reverse voltage they can withstand (this must

be at least three times the supply RMS voltage so the rectifier can

withstand the peak voltages). Please see the Diodes page for more

details, including pictures of bridge rectifiers.

OUTPUT:
http://www.kpsec.freeuk.com/acdc.htm#rmshttp://www.kpsec.freeuk.com/components/diode.htm#bridgehttp://www.kpsec.freeuk.com/acdc.htm#rmshttp://www.kpsec.freeuk.com/components/diode.htm#bridge


53/70

FILTER:

Smoothing is performed by a large value electrolytic capacitor

connected across the DC supply to act as a reservoir, supplying current to

the output when the varying DC voltage from the rectifier is falling. The

diagram shows the unsmoothed varying DC (dotted line) and the smoothed

DC (solid line). The capacitor charges quickly near the peak of the varying

DC, and then discharges as it supplies current to the output.

Note that smoothing significantly increases the average DC voltage to

almost the peak value (1.4 RMS value). For example 6V RMS AC is

rectified to full wave DC of about 4.6V RMS (1.4V is lost in the bridge

rectifier), with smoothing this increases to almost the peak value giving

1.4 4.6 = 6.4V smooth DC.
http://www.kpsec.freeuk.com/components/capac.htm#polarisedhttp://www.kpsec.freeuk.com/acdc.htm#rmshttp://www.kpsec.freeuk.com/components/capac.htm#polarisedhttp://www.kpsec.freeuk.com/acdc.htm#rms


54/70

Smoothing is not perfect due to the capacitor voltage falling a little as it

discharges, giving a small ripple voltage. For many circuits a ripple which is

10% of the supply voltage is satisfactory and the equation below gives the

required value for the smoothing capacitor. A larger capacitor will give lessripple. The capacitor value must be doubled when smoothing half-wave DC.

C = smoothing capacitance in farads (F)Io = output current from the supply in amps (A)Vs = supply voltage in volts (V), this is the peak value of the unsmoothedDCf = frequency of the AC supply in hertz (Hz), 50Hz in the UK

REGULATOR:

The output voltage from the capacitor is more filtered and finally

regulated. The voltage regulator is a device, which maintains the output

voltage constant irrespective of the change in supply variation, load

variation and temperature changes. Here we use one fixed voltage regulator

namely LM 7805. The regulator IC 7805 is a +5V regulator.

TRANSFORMER:

Transformers convert AC electricity from one voltage to another with

little loss of power. Transformers work only with AC and this is one of the

reasons why mains electricity is AC.


55/70

Step-up transformers increase voltage, step-down transformers reduce

voltage. Most power supplies use a step-down transformer to reduce the

dangerously high mains voltage (230V in UK) to a safer low voltage.

The input coil is called the primary and the output coil is called the

secondary. There is no electrical connection between the two coils, instead

they are linked by an alternating magnetic field created in the soft-iron core

of the transformer. The two lines in the middle of the circuit symbol

represent the core.

Transformers waste very little power so the power out is (almost) equal tothe power in. Note that as voltage is stepped down current is stepped up.

The ratio of the number of turns on each coil, called the turns ratio,

determines the ratio of the voltages. A step-down transformer has a large

number of turns on its primary (input) coil which is connected to the high

voltage mains supply, and a small number of turns on its secondary (output)

coil to give a low output voltage.

TRANSFORMER SYMBOL:


56/70

EXAMPLE:

ADVANTAGES

This project decreases the rate of accidents in the highways and Ghats areas

Low cost and easy to implement.

Can cover maximum area in a zone.

This can be implemented with other wireless technologies for adding more stuff.


57/70

DISADVANTAGES

Difficult in case of failure of RF transmitter.

RF Modules are to be protected from environment Hazards.

APPLICATIONS

It can be implemented in automated systems for wireless control.

Can be used at heavy traffic areas.

Used in school zones and ghat roads.

This can be uses in driving guidance systems and automatic navigation system

CODE

;...........speed control of dc motor usingRF ............................;...........................crystal frequency = 11.0592mhz............;...........................TRANSMITTERSECTION........................

$mod51

sw1 bit p2.0sw2 bit p2.1sw3 bit p2.2sw4 bit p2.3sw5 bit p2.4sw6 bit p2.5RS BIT P3.2


58/70

RW BIT P3.3EN BIT P3.4

DAT EQU P0out equ p1

;...........................................

ORG 00HJMP START;---------------------------------------

ORG 030H

START:MOV SP,#08HMOV P1,#0ffHMOV P2,#0FFHMOV P3,#0FFHMOV P0,#0FFHCALL INIT_LCDCALL CLEAR_LCDMOV DPTR,#MSG1CALL DISPCALL DEBOUNCE

BEGIN:n0: jb sw1,n1

mov out,#1fHMOV DPTR,#MSG2CALL DISPCALL DEBOUNCEcall delay1call display1jmp n0

n1: jb sw2,n2mov out,#2fHMOV DPTR,#MSG3CALL DISPCALL DEBOUNCEcall delay1call display2jmp n0

n2: nop

n3: nop

n4: jb sw5,n5mov out,#5fHmov dptr,#msg6


59/70

call dispcall debounce

n5: jmp n0

;--------------------------------------DEBOUNCE:MOV R6,#200DJNZ R6,$RET

;.......................................................................................; INITIALIZE THE LCD;---------------------------------------------------------INIT_LCD:

SETB EN ;enable lcdCLR RS ;It is a commandMOV DAT ,#32H ;8 Bit data,2lineCLR ENLCALL WAIT_LCDSETB EN ;enable lcdCLR RS ;It is a commandMOV DAT ,#38H ;8 Bit data,2lineCLR ENLCALL WAIT_LCD

;--------------------------------------------------------SETB ENCLR RSMOV DAT ,#0EH ;LCD ON -CURSOR ONCLR ENLCALL WAIT_LCD

;---------------------------------------------------------SETB EN

CLR RSMOV DAT ,#06H ;Auto increment cursorCLR ENLCALL WAIT_LCDRET

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

CUR_OFF:SETB ENCLR RSMOV DAT ,#0CHCLR ENLCALL WAIT_LCD

RET;----------------------------------------------------------


60/70

CLEAR_LCD:SETB ENCLR RSMOV DAT,#01CLR EN

LCALL WAIT_LCDRET;----------------------------------------------------------WRITE_TEXT:

SETB ENSETB RSMOV DAT,ACLR ENLCALL WAIT_LCD

RET;----------------------------------------------------------WAIT_LCD:

SETB ENCLR RSSETB RWMOV DAT ,#0FFHMOV A,DATJB ACC.7 ,WAIT_LCDCLR ENCLR RWRET

;-----------------------------------------------------------; SUB SETS THE CURSOR POSITION.;--LINE 1;-----------------------------------------------------------PLACECUR:

MOV A, BADD A,#80H ; CONSTRUCT CONTROL WORD FOR LINE

1--SETCUR:

SETB ENCLR RSCLR RW

MOV DAT ,ACLR ENCALL WAIT_LCDRET

;-----------------------------------------------------------;--CURSOR POSITION LINE2;----------------------------------------------------------PLACECUR2:


61/70

MOV A,BADD A,#0C0H

SETCUR2:SETB ENCLR RS

CLR RWMOV DAT,ACLR ENCALL WAIT_LCDRET

;-------------------------------;--DISP sub to display string;---------------------------------DISP: MOV B,#00

CALL PLACECURMOV R1, #16

J210: CLR AMOVC A, @A+DPTRCALL WRITE_TEXTINC DPTRDJNZ R1,J210

MOV B,#00CALL PLACECUR2MOV R1,#16

J211: CLR AMOVC A, @A+DPTR

CALL WRITE_TEXTINC DPTRDJNZ R1,J211RET

;---------------------------------------display1:

back: jnb sw6,gk1JNB SW5,GK1jb sw1,backmov out,#6fhmov dptr,#msgacall disp

call delay1

back1: jnb sw6,gk1JNB SW5,GK1jb sw1,back1mov out,#7fhmov dptr,#msgbcall disp


62/70

call delay1

back2: jnb sw6,gk1JNB SW5,GK1jb sw1,back2

mov out,#8fhmov dptr,#msgccall dispcall delay1

back3: jnb sw6,gk1JNB SW5,GK1jb sw1,back3mov out,#9fhmov dptr,#msgdcall dispcall delay1

gk1: RET

;......................................................display2:

back0: jnb sw6,gk2JNB SW5,GK2jb sw2,back0mov out,#0afhmov dptr,#msgecall dispcall delay1

back10: jnb sw6,gk2JNB SW5,GK2jb sw2,back10mov out,#0bfhmov dptr,#msgfcall dispcall delay1

back20: jnb sw6,gk2JNB SW5,GK2jb sw2,back20mov out,#0cfhmov dptr,#msggcall dispcall delay1


63/70

back30: jnb sw6,gk2JNB SW5,GK2jb sw2,back30mov out,#0dfh

mov dptr,#msghcall dispcall delay1

gk2: RET

;......................................................debounce2:

mov r2,#25gg20: mov r3,#255

djnz r3,$djnz r2,gg20ret

;.....................................................delay1:

mov r1,#7kk1: mov r2,#255kk2: mov r3,#255

djnz r3,$djnz r2,kk2djnz r1,kk1ret

;......................................................MSG1:DB' RF CONTROL OF ',' CAR ',0MSG2:DB' SPEED ',' INC ',0MSG3:DB' SPEED ',' DEC ',0MSG6:DB' ENGINE ',' STOPPED ',0MSGa:DB' LOW ',' speed ',0MSGb:DB' 2nd ',' speed ',0MSGc:DB' 3rd ',' Speed ',0MSGd:DB' 4th ',' speed ',0MSGe:DB' HI ',' Speed ',0MSGf:DB' 2nd ',' Speed ',0

MSGg:DB' LOW ',' speed ',0MSGh:DB' MOTOR ',' STOPPED ',0;----------------------------------------

end


64/70

;.....RF BASED SPEED CONTROL OF DC MOTOR.........;...RECEIVER SECTION......;............11.0592 MHZ...........

$MOD51

RX_DATA EQU P1OUT EQU P2.0RELAY_F EQU P2.2RELAY_R EQU P2.1

;..............................................ORG 00HJMP START

ORG 030HSTART:

MOV P1,#0FFHMOV P2,#1fH

N0: MOV A,RX_DATACJNE A,#0F1H,N1CALL RUN

N1: CJNE A,#2fH,N2CALL SPEED300




N5: CJNE A,#6fH,N6CALL SPEED1200D

N6: CJNE A,#7fH,N7

CALL SPEED600D

N7: CJNE A,#0cfH,N8CALL SPEED300D

N8: CJNE A,#0dfH,N9CALL RUND


65/70

N9: nop

NA: nop

NB: CJNE A,#5fH,NC

CALL STOPNC: JMP N0

;.................................................................................RUN:BACK: CLR OUT

CALL DELAY1SETB OUTCALL DELAY9MOV A,RX_DATACJNE A,#6fH,K1JMP BACK

K1: RET;.................................................................................SPEED300:BACK2: CLR OUT

CALL DELAY2SETB OUTCALL DELAY8MOV A,RX_DATACJNE A,#7fH,K2JMP BACK2

K2: RET;..................................................................................SPEED600:BACK3: CLR OUT

CALL DELAY4SETB OUTCALL DELAY6MOV A,RX_DATACJNE A,#8fH,K3

JMP BACK3K3: RET;............................................................................SPEED1200:BACK4: CLR OUT

CALL DELAY7SETB OUT


66/70

CALL DELAY3MOV A,RX_DATACJNE A,#9fH,K4JMP BACK4

K4: RET

;..........................................................................SPEED1400:BACK5: CLR OUT

MOV A,RX_DATACJNE A,#1fH,K5JMP BACK5

K5: RET;..........................................................................RUND:BACK6: CLR OUT

CALL DELAY1SETB OUTCALL DELAY9MOV A,RX_DATACJNE A,#6fH,K10JMP BACK6

K10: RET;.................................................................................SPEED300D:BACK7: CLR OUT

CALL DELAY2SETB OUTCALL DELAY8MOV A,RX_DATACJNE A,#0cfH,K20JMP BACK7

K20: RET;..................................................................................SPEED600D:BACK8: CLR OUT

CALL DELAY4SETB OUTCALL DELAY6MOV A,RX_DATACJNE A,#0bfH,K30JMP BACK8

K30: RET


67/70

;............................................................................SPEED1200D:BACK9: CLR OUT

CALL DELAY7

SETB OUTCALL DELAY3MOV A,RX_DATACJNE A,#0afH,K40JMP BACK9

K40: RET;.........................................................................

DELAY1:MOV R1,#2

X1: MOV R2,#230DJNZ R2,$DJNZ R1,X1RET

;........................................................................DELAY2:

MOV R7,#2X2: CALL DELAY1

DJNZ R7,X2RET

;........................................................................DELAY3:


DJNZ R7,X3RET

;........................................................................DELAY4:


DJNZ R7,X4

RET;........................................................................DELAY5:


DJNZ R7,X5RET


68/70

;........................................................................DELAY6:


DJNZ R7,X6RET;........................................................................DELAY7:


DJNZ R7,X7RET

;........................................................................DELAY8:


DJNZ R7,X8RET

;........................................................................DELAY9:


DJNZ R7,X9RET

;........................................................................

STOP:clr P2.0RET

;.........................................................................

END

CONCLUSION


69/70

The project VEHICLE SPEED CONTROL SYSTEM USING RF COMMUNICATION

has been successfully designed and tested.

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

of every module has been reasoned out and placed carefully thus contributing to the best working of

the unit. Thus the data to be sent is encoded within the transmitted signal so that a well designed

receiver can separate the data from the signal upon reception of this signal. The decoded data can

then be used to perform specified tasks.

Secondly, using highly advanced ICs and with the help of growing technology the project

has been successfully implemented.

This is a very useful technique to control the vehicle speed automatically.

By using Microcontroller , we Controlled the speed of the vehicle according to zones

It is mainly useful in the areas where high rate of accidents are recorded.

As in city traffic control to conserve the fuel and implement the traffic rules.

BIBILOGRAPHY

1. Theodore S. Rappaport, Wireless Communications Principles and Practices,

second edition,2001

2. Lathi, Digital Communications ,g.k publisher,2003

3. Sklar ,Digital Communications, second edition

WEBREFERENCES:


70/70

1. www.electronicstutorials.com

2. www.aimglobal.com

3. www.kernel.org

4. ONLamp.com

Car Speed REPORT

Documents

Transcript of Car Speed REPORT