6 Months Synopsis With PIC Microprocessor

8/10/2019 6 Months Synopsis With PIC Microprocessor

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GURU NANAK DEV UNIVERSITY (REGIONAL CAMPUS)

SYNOPSIS REPORT

ON

EMBEDDED SYSTEM

Submitted in the partial fulfillment of the requirement for the award of degree of

Bachelors of Technology

In

Submitted to

Mr. SHASHI RANA

Name of the Student: Hiteshwar Dutt

Name of the Training Guide:

Dapinder Lalotra

University Roll Number: 2010ECA1721


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INFOWIZ is an ISO 9001:2008 certified company. It has been working from more

than 5 years in the field of IT and Web Development and has been providing its

clients with its exceptional quality and Web Design, Development and SEO

service.Infowizs clients ranges from individuals to professionals and small, medium

and large scaled Businesses. In 2008, Info wiz entered into IT outsourcing and

partnered successfully with many offshore Web and SEO companies of

US,UK,France,Ireland,Canada and

Australia etc to provide them quality and timely services. INFOWIZ does not boost

itself of being the best Development Company but automatically enjoys reputable

position among top Web Development companies because Info wiz timely deliver and

quality work. Employees of Info wiz dont claim for something they cant deliver.

Before taking a project from a client, employee asks Info wiz for all their needs and

requirements. After that skilled of employee and team of professionals analyze the

need and come up with a plan as how they can work to completely satisfy those

requirements of our clients. Then they work step by step keeping their client informed

about the progress and complete the project in time giving complete contentment to

them .From concept building to implementation of any project, their team manages

projects efficiently up to its completion. Their tactful strategy and dedication toward

quality work has given us to the recognition they enjoy and that is why their clients

only come back to them whenever they require any kind of web related solutions.

They do not only emphasize on formulating an attractive solution to their clients, but

they believe in providing a workable solution. INFOWIZ offers research based Search

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ACKNOWLEDGEMENT

Success is a sweet fruit, which everyone want to strives to taste. To achieve this goal,

one has to put in physical and mental efforts. Each time I write this report, gain strong

appreciation for the following fact: I could not do it without the help of many talented

and dedicated people. So I wish to express my appreciation for those whose help has

been most valuable.

Firstly, I would like to express our gratitude and appreciation to Mr.Harjit Singh

(head of company), who explained us everything about training process as the

company and made us familiar with the company staff. We are equally grateful to Er.

Sunil kumar (instructor),who shorted out many of our problems regarding the training

and gave us the proper material to work with.

We are also grateful to(training and placement officer)for arranging the

six week training for us and providing us with all necessary information about the

same.

Finally I would like to say thanks to all the people of the company for their kind

operation.


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ABSTRACT

The usual reason for embedding a computer is to interact with the

environment, often by monitoring and controlling external machinery. Many

embedded systems have substantially

different design constraints than desktop computing applications. No single

characterization applies to the diverse spectrum of embedded systems. Some

combination of cost pressure, long life-cycle, real-time requirements, reliability

requirements, and design culture dysfunction can make it difficult to be successful

applying traditional computer design methodologies and tools to embedded

applications there is currently little tool support for expanding embedded computer

design to the scope of holistic embedded system design. Knowing the strengths and

weaknesses of current approaches can set expectations appropriately, identify risk

areas to tool adopters, and suggest ways in which tool builders can meet industrial

needs?

Many embedded systems have requirements that differ significantly

both in details and in scope from desktop computers. The demands of the specific

application and the interface with external equipment may dominate the system

design. Long life-cycles and in some cases extreme cost sensitivity require more

attention to optimization based on these goals rather than maximizing the

computational throughput.

Recent interest in hardware/software co design is a step in the right

direction, as it permits tradeoffs between hardware and software that are critical for

more cost-effective embedded systems.


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Introduction:-

We are living in the Embedded World. You are surrounded with many embedded

products and your daily life largely depends on the proper functioning of these gadgets.

Television, Radio, CD player of your living room, Washing Machine or Microwave

Oven in your kitchen, Card readers, Access Controllers, Palm devices of your work space

enable you to do many of your tasks very effectively. Apart from all these, many

controllers embedded in your car take care of car operations between the bumpers and

most of the times you tend to ignore all these controllers.

Theoretically, an embedded controller is a combination of a piece of microprocessor

based hardware and the suitable software to undertake a specific task.

These days designers have many choices in microprocessors/ microcontrollers.

Especially, in 8 bit and 32 bit, the available variety really may overwhelm even an

experienced designer. Selecting a right microprocessor may turn out as a most difficult

first step and it is getting complicated as new devices continue to pop-up very often.

In the 8 bit segment, the most popular and used architecture is Intel's 8031. Market

acceptance of this particular family has driven many semiconductor manufacturers to

develop something new based on this particular architecture. Even after 25 years of

existence, semiconductor manufacturers still come out with some kind of device using

this 8031 core.


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EMBEDDED SYSTEM

Embedded system employs a combination of software & hardware to perform a

specific function. It is a part of a larger system which may not be a computer Works

in a reactive & time constrained environment.

Any electronic system that uses a CPU chip, but that is not a general-purpose

workstation, desktop or laptop computer is known as embedded system. Such systems

generally use microprocessors; microcontroller or they may use custom-designed

chips or both. They are used in automobiles, planes, trains, space vehicles, machine

tools, cameras, consumer and office appliances, cell phones, PDAs and other

handhelds as well as robots and toys. The uses are endless, and billions of

microprocessors are shipped every year for a myriad of applications. In embedded

systems, the software is permanently set into a read-only memory such as a ROM or

flash memory chip, in contrast to a general-purpose computer that loads its programs

into RAM each time.

A specialized computer system that is part of a larger system or machine typically, an

embedded system is housed on a single microprocessor board with the programs

stored in ROM. Virtually all appliances that have a digital Interface -- watches,

microwaves, VCRs, cars -- utilize embedded systems. Some embedded systems

include an operating system, but many are so specialized that the entire logic can be

implemented as a single program. Embedded systems programming is the

development of programs intended to be part of a larger operating system or, in a

somewhat different usage, to be incorporated on a microprocessor that can then be

included as part of a variety of hardware devices. Several other definitions are:

A combination of computer hardware and software, and perhaps additional

mechanical or other parts, designed to perform a dedicated function. In some cases,

embedded systems

Are part of a larger system or product, as in the case of an antilock braking system in

a car. Contrast with general-purpose computer.


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A specialized computer system which is dedicated to a specific task. Embedded

systems range in size from a single processing board to systems with operating

systems (ex, Linux, Windows NT Embedded). Examples of embedded systems are

medical equipment and manufacturing equipment.

A computer system that is a component of a larger machine or system. Embedded

systems can respond to events in real time. Most digital appliances, such as watches

or cars, utilize an embedded system.

Hardware and software that forms a component of some larger system and is

expected to function without human intervention. Typically an embedded system

consists of a single board microcomputer with software in ROM, which starts running

a dedicated application as soon as power is turned on and does not stop until power is

turned off.

An embedded system is some combination of computer hardware and software,

either fixed in capability or programmable, that is specifically designed for a

particular kind of application device. Industrial machines, automobiles, medical

equipment, cameras, household appliances, airplanes, vending machines, and toys (as

well as the more obvious cellular phone and PDA) are among the myriad possible

hosts of an embedded system.

A phrase that refers to a device that contains computer logic on a chip inside it.

Such equipment is electrical or battery powered. The chip controls one or more

functions of the equipment, such as remembering how long it has been since the

device last received maintenance,

An embedded system is a special purpose computer system, which is completely

encapsulated by the device it controls. An embedded system has specific requirements

and performs pre-defined tasks, unlike a general-purpose personal computer.

5 An embedded system is a special-purpose computer system, which is completely

encapsulated by the device it controls. An embedded system has specific requirements

and performs pre-defined tasks, unlike a general-purpose personal computer.


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o

EMBEDDED SYSTEM APPLICATIONS:-

Consumer electronics, e.g., cameras, cell phones etc

Consumer products, e.g. washers, microwave ovens etc.

Automobiles (anti-lock braking, engine control etc.)

Industrial process controller &defence applications.

Computer/Comm. products, e.g. printers, FAX machines etc.

Medical Equipments.

ATMs

Aircrafts


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o TYPES OF MICROCONTROLLER ARCHITECTURE:

There are two types of Microcontroller architecture designed for embedded system

development. These are:

1) RISC- Reduced instruction set computer

2)

CISC- Complex instruction set computer

DIFFERENCE BETWEEN CISC AND RISC:

CISC stands for Complex Instruction Set Computer. Most PC's use CPU based

on this architecture. For instance Intel and AMD CPU's are based on CISC

architectures. Typically CISC chips have a large amount of different and

complex instructions. In common CISC chips are relatively slow (compared to

RISC chips) per instruction, but use little (less than RISC) instructions. MCS-

51 family microcontrollers based on CISC architecture.

RICS stands for Reduced Instruction Set Computer. The philosophy behind it

is that almost no one uses complex assembly language instructions as used by

CISC, and people mostly use compilers which never use complex instructions.

Therefore fewer, simpler and faster instructions would be better, than the

large, complex and slower CISC instructions. However, more instructions are

needed to accomplish a task. Atmels AVR microcontroller based on RISC

architecture.

COMPUTER DESIGN REQUIREMENTS

Embedded computers typically have tight constraints on both functionality and

implementation. In particular, they must guarantee real time operation reactive to

external events, conform to size and weight limits, budget power and cooling

consumption, satisfy safety and reliability requirements, and meet tight cost targets.


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Real time/reactive operation

Real time system operation means that the correctness of a

computation depends, in part, on the time at which it is delivered. The Signal

Processing and Mission Critical example systems have a significant requirement for

real time operation in order to meet external I/O and control stability requirements.

Reactive computation means that the software executes in response to external

events. These events may be periodic, in which case scheduling of events to

guarantee performance may be possible. On the other hand, many events may be a

periodic, in which case the maximum event arrival rate must be estimated in order to

accommodate worst case situations. Most embedded systems have a significant

reactive component.

Design challenge:

Worst case design analyses without undue pessimism in the face of hardware

with statistical performance characteristics (e.g.,cache memory).

Small size, low weight

In transportation and portable systems, weight may be critical for fuel

economy or human endurance. Among the examples, the Mission Critical system has

much more stringent size and weight requirements than the others because of its use

in a flight vehicle, although all examples have restrictions of this type.

Design challenges:

Non-rectangular, non-planar geometries.

Packaging and integration of digital, analog, and power circuits to reduce size.

Safe and reliable

Some systems have obvious risks associated with failure. In mission-critical

applications such as aircraft flight control, failure of the embedded computer.

However, many embedded systems that could cause personal or property

damage. This vulnerability is often resolved at the system level.


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o History of 8051

Intel Corporation introduced an 8-bit microcontroller called 8051 in 1981 this

controller had 128 bytes of RAM, 4k bytes of on chip ROM, two timers, one serial

port, and four ports all are on single chip. The 8051 is an 8 bit processor, meaning that

the CPU can work on only 8 bit data at a time. Data larger than 8 bits broken into 8 bit

pieces to be processed by CPU. It has for I/O 8 bit wide.

Features of the 8051:- Quantity

1)

ROM 4K bytes

2)

RAM 128 bytes

3) Timer 2

4)

I/O pins 32

5)

Serial port 1

6) Interrupt sources 6


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o 8051 ARCHITECTURE OVERVIEW

The 8051 family is one of the most common microcontroller architectures used

worldwide. 8051 based microcontrollers are offered in hundreds of variants from

many different silicon manufacturers 7.

The 8051 is based on an 8-bit CISC core with Harvard architecture. It's an 8-bit CPU,

optimized for control applications with extensive Boolean processing (single-bit logic

capabilities), 64K program and data memory address space and various on-chip

peripherals.

The 8051 microcontroller family offers developers a wide variety of high-integration

and cost-effective solutions for virtually every basic embedded control application.

From traffic control equipment to input devices and computer networking products,

8051 u.c deliver high performance together with a choice of configurations and

options matched to the special needs of each application.

Whether it's low power operation, higher frequency performance, expanded on-chip

RAM, or an application-specific requirement, there's a version of the 8051

microcontroller that's right for the job. When it's time to upgrade product features and

functionality, the 8051 architecture puts you on the first step of a smooth and cost-

effective upgrade path - to the enhanced performance of the 151 and 251

microcontrollers.


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BLOCK DIAGRAM OF 8081:-

Block diagram of 8051

o PIN CONFIGURATION OF 8051


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There are four ports P0, P1, P2 and P3 each use 8 pins, making them 8-bit ports.

All the ports upon RESET are configured as output, ready to be used as output ports.

To use any of these ports as an input port, it must be programmed.


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Port 0:- Port 0 occupies a total of 8 pins (pins 32-39) .It can be used for input

or output. To use the pins of port 0 as both input and output ports, each pin

must be connected externally to a 10K ohm pull-up resistor. This is due to the

fact that P0 is an open drain, unlike P1, P2, and P3.Open drain is a term used

for MOS chips in the same way that open collector is used for TTL chips.

With external pull-up resistors connected upon reset, port 0 is configured as an

output port. For example, the following code will continuously send out to

port 0 the alternating values 55H and AAH

Port 0 as input: - With resistors connected to port 0, in order to make it an

input, the port must be programmed by writing 1 to all the bits. In the

following code, port 0 is configured first as an input port by writing 1's to it,

and then data is received from the port and sent to P1.

Dual Role of Port 0:-Port 0 is also designated as AD0-AD7, allowing it to be

used for both address and data. When connecting an 8051/31 to an external

memory, port 0 provides both address and data. The 8051 multiplexes address

and data through port 0 to save pins. ALE indicates if P0 has address or data.

When ALE = 0, it provides data D0-D7, but when ALE =1 it has address and

data with the help of a 74LS373 latch.

Port 1:- Port 1 occupies a total of 8 pins (pins 1 through 8). It can be used as

input or output. In contrast to port 0, this port does not need any pull-upresistors since it already has pull-up resistors internally. Upon reset, Port 1 is


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configured as an output port. For example, the following code will

continuously send out to port1 the alternating values 55h &AAh

Port 1 as input:-To make port1 an input port, it must be programmed as such

by writing 1 to all its bits. In the following code port1 is configured first as an

input port by writing 1s to it, then data is received from the port and saved in

R7 ,R6 & R5.

Port 2 :-Port 2 occupies a total of 8 pins (pins 21- 28). It can be used as input

or output. Just like P1, P2 does not need any pull-up resistors since it already

has pull-up resistors internally. Upon reset, Port 2 is configured as an output

port. For example, the following code will send out continuously to port 2 the

alternating values 55h and AAH. That is all the bits of port 2 toggle

continuously.

Port 2 as input:- To make port 2 an input, it must programmed as such by

writing 1 to all its bits. In the following code, port 2 is configured first as an

input port by writing 1s to it. Then data is received from that port and is sent

to P1 continuously.

Dual role of port 2:- In systems based on the 8751, 8951, and DS5000, P2 is

used as simple I/O. However, in 8031-based systems, port 2 must be used

along with P0 to provide the 16-bit address for the external memory. As

shown in pin configuration 8051, port 2 is also designed as A8-A15, indicating

the dual function. Since an 8031 is capable of accessing 64K bytes of externalmemory, it needs a path for the 16 bits of the address. While P0 provides the

lower 8 bits via A0-A7, it is the job of P2 to provide bits A8-A15 of the

address. In other words, when 8031 is connected to external memory, P2 is

used for the upper 8 bits of the 16 bit address, and it cannot be used for I/O.

Port 3:-port 3 occupies a total of 8 pins, pins 10 through 17. It can be used as

input or output. P3 does not need any pull-up resistors, the same as P1 and P2

did not. Although port 3 is configured as an output port upon reset. Port 3 has


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the additional function of providing some extremely important signals such as

interrupts.

This information applies both 8051 and 8031 chips. There functions are as

follows:-

PORT 3 Function pin

1) P3.0 RxD 10

2) P3.1 TxD 11

3) P3.2 ___

Int0

12

4) P3.3 ___

Int1

13

5) P3.4 T0 14

6) P3.5 T1 15

7) P3.6 ___

WR

16

8) P3.7 ___

RD

17

P3.0 and P3.1 are used for the RxD and TxD serial communications signals. Bits P3.2

and P3.3 are set aside for external interrupts. Bits P3.4 and P3.5 are used for timers 0

and 1. Finally P3.6 and P3.7 are used to provide the WR and RD signals of external

memories connected in 8031 based systems.

ALE/PROG :- Address Latch Enable is an 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


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pin is weakly pulled high. Setting the ALE-disable bit has no effect if the

microcontroller is in external execution mode.

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

When the AT89S8252 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 when 12-volt

programming is selected.

XTAL1:- Input to the inverting oscillator amplifier and input to the internal

clock operating circuit.

XTAL2 :-Output from the inverting oscillator amplifier.

oFEATURES:-

Compatible with MCS-51Products

8K bytes of In-System Reprogrammable Downloadable Flash Memory

- SPI Serial Interface for Program Downloading- Endurance: 1,000 Write/Erase Cycles

2K bytes EEPROM

- Endurance: 100,000 Write/Erase Cycles

4.0V to 6V Operating Range

Fully Static Operation: 0 Hz to 24 MHz


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Three-Level Program Memory Lock

256 x 8 bit Internal RAM

32 Programmable I/O Lines

Three 16 bit Timer/Counters

Nine Interrupt Sources

Programmable UART Serial Channel

SPI Serial Interface

Low Power Idle and Power Down Modes

Interrupt Recovery From Power Down

Programmable Watchdog Timer

Dual Data Pointer

Power Off Flag

256 x 8 bit Internal RAM

32 Programmable I/O Lines

Three 16 bit Timer/Counters

o HARDWARE INTERFACINGS AND PROGRAMMING:-


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There are two types of programming language used for microcontroller programming:

1) Low Level Language(Assembly Language)

2)

High Level Language(C Language )

o INTERFACING OF VARIOUS DEVICES:-

1) LED Interfacing

C code for Blinking LEDs connected on PORT2:


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#include

void delay(unsigned int time);

void main(void)

0{

While(1)

{

P2=0xff;

delay(20);

P2=0x55;

}

}

void delay(unsigned int time)

{

Unsigned intI,j;

For(i=0;i


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The function of each of the connections is shown in the table below:-

Pins 1 & 2 are the power supply lines, VSS & VDD. The VDD pin should be

connected to the positive supply & VSS to the 0V supply or ground.

Although the LCD module data sheets specify 5V D.C. supply (at only a few

milliamps), supplies of 6V & 4.5V both work well, and even 3V is sufficient for some

modules. Consequently, these modules can be effectively and economically powered

by batteries.

Pin 3 is a control pin, VEE, which is used to alter the contrast of the display.

Ideally, these pin should be connected to a variable voltage supply. A preset

potentiometer connected between the power supply lines, with its wiper

connected to the contrast pin is suitable in many cases, but be aware that some

modules may require a negative potential; as low as 7V in some cases. For

absolute simplicity, connecting this pin to 0V will often suffice. Ideally, these

pin should be connected to a variable voltage supply. A preset potentiometer

connected between the power supply lines, with its wiper connected to the

contrast pin is suitable in many cases, but be aware that some modules may

require a negative potential; as low as in some cases. For absolute simplicity,

connecting this pin to will often suffice.

Ideally, these pin should be

connected to a variable voltage supply. A preset potentiometer connected

between the power supply lines, with its wiper connected to the contrast pin is

suitable in many cases, but be aware that some modules may require a

negative potential; as low as in some cases. For absolute simplicity,

connecting this pin to 0V will often suffice. A preset potentiometer connected

between the power supply lines, with its wiper connected to the contrast pin is

suitable in many cases, but be aware that some modules may require anegative potential; as low as in some cases. For absolute simplicity,

connecting this pin to 0V will often suffice


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Pin 4 is

register select

(RS) line. Pin

no.

NAME FUNCTION

1 Vss Ground

2 Vdd +ve supply

3 Vee contrast

4 RS Register select

5 R/W Read/Write

6 E Enable

7 D0 Data Bit 0

8 D1 Data Bit 1

9 D2 Data Bit 2

10 D3 Data Bit 3

11 D4 Data Bit 4

12 D5 Data Bit 5

13 D6 Data Bit 6

14 D7 Data Bit 7

Three command control inputs. When this line is low, data bytes transferred to the

display are treated as commands, and data bytes read from the display indicate its

status. By setting the RS line high, character data can be transferred to and from themodule.

Pin 5 is (R/W) line. This line is pulled low in order to write commands or

character data to the module, or pulled high to read character data or status

information from its registers.

Pin 6 is Enable (E) line. This input is used to initiate the actual transfer of

commands or character data between the module and the data lines. When

writing to the display, data is transferred only on the high to low transition of

this signal. However, when reading from the display, data will become


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available shortly after the low to high transition and remain available until the

signal falls low again.

Pins 7 to 14 are the eight data bus lines (D0 to D7). Data can be transferred to

and from the display, either as a single 8-bit byte or as two 4-bit nibbles. In

the latter case, only the upper four data lines (D4 to D7) are used. This $-bit

mode is beneficial when using a microcontroller, as fewer I/O lines are

required.


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C code for LCD display:

#include //defining library

//-------------------------------------------------------------------------

voidmsdelay(unsigned int time); //defining function prototype

voidlcd_cmd(unsigned char value);

voidlcd_data(unsigned char value);

//-------------------------------------------------------------------------

sfr ldata = 0xA0; //defining constant for Port2

sbit rs = P3^0;

sbit rw = P3^1; //defining constant for Port3.0

sbit en = P3^2;

//--------------------------------------------------------------------------

void main()

{

lcd_cmd(0x38); //init. LCD 2 lines, 5x7 matrix

msdelay(50);

lcd_cmd(0x0E); //Display On, Cursor On

msdelay(50);

lcd_cmd(0x01); //Clear LCD

msdelay(50);

lcd_cmd(0x06); //Shift Cursor Right

msdelay(50);

lcd_cmd(0x80); //Line 1,Position 0

msdelay(50);lcd_data('G'); //Display Letter N

msdelay(50);

lcd_data('A');

msdelay(50);

lcd_data('U');

msdelay(50);

lcd_data('R');

msdelay(50);


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lcd_data('A');

msdelay(50);

lcd_data('V);

msdelay(50);

}

voidlcd_cmd(unsigned char value)

{

ldata = value; //Put Value on Lcd Port

rs = 0;

rw = 0;

en = 1; //strobe the enable pin

msdelay(1);

en = 0;

}

voidlcd_data(unsigned char value)

{

ldata = value; //Put Value on Lcd Port

rs = 1;

rw = 0;

en = 1; //strobe the enable pin

msdelay(1);

en = 0;}

voidmsdelay(unsigned int time)

{

inti,j;

for(i=0;i


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3)Serial communication between At89v51rd2 and PC:-

a)Serial Reception(From PC to microcontroller)

C- Code for serial reception:

#include

sbitrs=P3^0;

sbitrw=P3^1;

sbit en=P3^2;

sfrldata=0x90;

voidlcom(unsigned char value);

voidldat(unsigned char value);

void delay(unsigned int time);

unsigned char first[]="GAURAV WADHWA";

unsignedint i;

unsigned char first1[]="IET BHADDAL";

unsigned char mybyte;

void main()

{

lcom(0x38);

lcom(0x06);

lcom(0x0e);

lcom(0x01);

for(i=0;i


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delay(50);

lcom(0x01);

TMOD=0X20;

TH1=0XFD;

TCON=0X00;

SCON=0X50;

TR1=1;

while(1)

{

while(RI==0);

mybyte=SBUF;

ldat(mybyte);

}

RI=0;

}

voidlcom(unsigned char value)

{

ldata=value;

rs=0;

rw=0;

en=1;

delay(5);

en=0;

}

voidldat(unsigned char value){

ldata=value;

rs=1;

rw=0;

en=1;

delay(5);

en=0;


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}

void delay(unsigned int time)

{

unsignedintk,j;

for(k=0;k


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C code for seven segment display :

#include //defining library

//-------------------------------------------------------------------------

voidmsdelay(unsigned int time); //defining function prototype

void compare();

sfrport_data = 0xA0; //defining constant for Port2

int m = 0X00;

//--------------------------------------------------------------------------

void main()

{

while(1)

{

compare();

port_data = m;

msdelay(15);

m--;

}

}

void compare()

{

if(m == 0X0F)

m = 0X09;

if(m == 0X1F)m = 0X19;

if(m == 0X2F)

m = 0X29;

if(m == 0X3F)

m = 0X39;

if(m == 0X4F)

m = 0X49;

if(m == 0X5F)


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m = 0X59;

if(m == 0X6F)

m = 0X69;

if(m == 0X7F)

m = 0X79;

if(m == 0X8F)

m = 0X89;

if(m == 0XFF)

m = 0X99;

if(m == ~0X01)

m = 0X99;

}

voidmsdelay(unsigned int time)

{

inti,j;

for(i=0;i


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PIC MICROCONTROLLER

PICis a family ofmodified Harvard architecturemicrocontrollersmade byMicrochip

Technology,derived from the PIC1650 originally developed byGeneral Instrument's

Microelectronics Division. The name PIC initially referred to "Peripheral Interface

Controller".

PICs are popular with both industrial developers and hobbyists alike due to their low

cost, wide availability, large user base, extensive collection of application notes,

availability of low cost or free development tools, and serial programming (and re-

programming with flash memory) capability. They are also commonly used in

educational programming as they often come with the easy to use 'pic logicator'

software.

History

Various older (EPROM) PIC microcontrollers

The original PIC was built to be used with General Instrument's new 16-bitCPU,the

CP1600.While generally a goodCPU,the CP1600 had poorI/Operformance, and the

8-bit PIC was developed in 1975 to improve performance of the overall system by

offloading I/O tasks from the CPU. The PIC used simplemicrocodestored in ROM to

perform its tasks, and although the term was not used at the time, it shares some

common features withRISCdesigns.
http://en.wikipedia.org/wiki/Modified_Harvard_architecturehttp://en.wikipedia.org/wiki/Modified_Harvard_architecturehttp://en.wikipedia.org/wiki/Microcontrollerhttp://en.wikipedia.org/wiki/Microcontrollerhttp://en.wikipedia.org/wiki/Microcontrollerhttp://en.wikipedia.org/wiki/Microchip_Technologyhttp://en.wikipedia.org/wiki/Microchip_Technologyhttp://en.wikipedia.org/wiki/Microchip_Technologyhttp://en.wikipedia.org/wiki/Microchip_Technologyhttp://en.wikipedia.org/wiki/General_Instrumenthttp://en.wikipedia.org/wiki/General_Instrumenthttp://en.wikipedia.org/wiki/General_Instrumenthttp://en.wikipedia.org/wiki/Central_processing_unithttp://en.wikipedia.org/wiki/Central_processing_unithttp://en.wikipedia.org/wiki/Central_processing_unithttp://en.wikipedia.org/wiki/General_Instrument_CP1600http://en.wikipedia.org/wiki/General_Instrument_CP1600http://en.wikipedia.org/wiki/CPUhttp://en.wikipedia.org/wiki/CPUhttp://en.wikipedia.org/wiki/CPUhttp://en.wikipedia.org/wiki/Input/outputhttp://en.wikipedia.org/wiki/Input/outputhttp://en.wikipedia.org/wiki/Input/outputhttp://en.wikipedia.org/wiki/Microcodehttp://en.wikipedia.org/wiki/Microcodehttp://en.wikipedia.org/wiki/Microcodehttp://en.wikipedia.org/wiki/Reduced_instruction_set_computerhttp://en.wikipedia.org/wiki/Reduced_instruction_set_computerhttp://en.wikipedia.org/wiki/Reduced_instruction_set_computerhttp://en.wikipedia.org/wiki/File:PIC16CxxxWIN.JPGhttp://en.wikipedia.org/wiki/Reduced_instruction_set_computerhttp://en.wikipedia.org/wiki/Microcodehttp://en.wikipedia.org/wiki/Input/outputhttp://en.wikipedia.org/wiki/CPUhttp://en.wikipedia.org/wiki/General_Instrument_CP1600http://en.wikipedia.org/wiki/Central_processing_unithttp://en.wikipedia.org/wiki/General_Instrumenthttp://en.wikipedia.org/wiki/Microchip_Technologyhttp://en.wikipedia.org/wiki/Microchip_Technologyhttp://en.wikipedia.org/wiki/Microcontrollerhttp://en.wikipedia.org/wiki/Modified_Harvard_architecture


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In 1985, General Instrument spun off their microelectronics division and the new

ownership cancelled almost everything board peripherals (serial communication

modules,UARTs,motor control kernels, etc.) and program memory from 256 words

to 64k words and more (a "word" is one assembly language instruction, varying from

12, 14 or 16bitsdepending on the specific PICmicrofamily).

PIC and PICmicro are registered trademarks of Microchip Technology. It is generally

thought that PIC stands for Peripheral Interface Controller,

and PIC1650 devices was "Programmable Interface Controller". The acronym was

quickly replaced with "Programmable Intelligent Computer".

PIN DIAGRAM(18f4520)
http://en.wikipedia.org/wiki/Microelectronicshttp://en.wikipedia.org/wiki/Microelectronicshttp://en.wikipedia.org/wiki/Serial_communicationshttp://en.wikipedia.org/wiki/Serial_communicationshttp://en.wikipedia.org/wiki/Serial_communicationshttp://en.wikipedia.org/wiki/Universal_asynchronous_receiver/transmitterhttp://en.wikipedia.org/wiki/Universal_asynchronous_receiver/transmitterhttp://en.wikipedia.org/wiki/Universal_asynchronous_receiver/transmitterhttp://en.wikipedia.org/wiki/Bithttp://en.wikipedia.org/wiki/Bithttp://en.wikipedia.org/wiki/Bithttp://en.wikipedia.org/wiki/Micro_programming_languagehttp://en.wikipedia.org/wiki/Micro_programming_languagehttp://en.wikipedia.org/wiki/Micro_programming_languagehttp://en.wikipedia.org/wiki/Micro_programming_languagehttp://en.wikipedia.org/wiki/Bithttp://en.wikipedia.org/wiki/Universal_asynchronous_receiver/transmitterhttp://en.wikipedia.org/wiki/Serial_communicationshttp://en.wikipedia.org/wiki/Microelectronics


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FEATURES


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NEW CORE FEATURES

All of the devices in the PIC18F2420/2520/4420/4520

family incorporate a range of features that can significantly

reduce power consumption during operation.

Key items include:

Alternate Run Modes: By clocking the controller

from the Timer1 source or the internal oscillator

block, power consumption during code execution

can be reduced by as much as 90%.

Multiple Idle Modes: The controller can also run

with its CPU core disabled but the peripherals still

active. In these states, power consumption can be

reduced even further, to as little as 4% of normal

operation requirements.

On-the-Fly Mode Switching: The powermanaged

modes are invoked by user code during

operation, allowing the user to incorporate

power-saving ideas into their applications

software design.

Low Consumption in Key Modules: The

power requirements for both Timer1 and theWatchdog Timer are minimized.


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MULTIPLE OSCILLATOR OPTIONS

AND FEATURES

All pin of the devices in the PIC18F2420/2520/4420/4520

family offer ten different oscillator options, allowing

users a wide range of choices in developing application

hardware. These include:

Four Crystal modes, using crystals or ceramic

resonators

Two External Clock modes, offering the option of

using two pins (oscillator input and a divide-by-4

clock output) or one pin (oscillator input, with the

second pin reassigned as general I/O)

Two External RC Oscillator modes with the same

pin options as the External Clock modes

An internal oscillator block which provides an

8 MHz clock and an INTRC source

(approximately 31 kHz), as well as a range of

6 user-selectable clock frequencies, between

125 kHz to 4 MHz, for a total of 8 clock

frequencies.

A Phase Lock Loop (PLL) frequency multiplier,

available to both the High-Speed Crystal and Internal

Oscillator modes, which allows clock speeds of

up to 40 MHz. Used with the internal oscillator, the

PLL gives users a complete selection of clockspeeds, from 31 kHz to 32 MHzall without using

an external crystal or clock circuit.

Besides its availability as a clock source, the internal

oscillator block provides a stable reference source that

gives the family additional features for robust

operation:

Documents

6 Months Synopsis With PIC Microprocessor