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1. BASICS OF A COMPUTER

Computer

Computer is an electronic machine that can manipulate date. It accepts and

store input data and output the processed data in required format.

History of Computer:

Charles Babbage is called as “Father of Computer”

His inventions: Difference Engine and Analytical Engine

Specification:

It can store the information on punch cards during 1800’s

Father of Modern Computer Science: Alan Turing

First purpose electronic digital computer: ENIAC

ENIAC means Electronic Numerical Integrator and Calculator

Parts of a computer:

Functional Unit of a Computer:

Arithmetic and Logic Unit (ALU)

ALU performs both logical and arithmetical operations like addition,

subtraction, multiplication and division.

Control Unit (CU)

It controls the operations for all the parts of the computer.

Fetching: It gets an instruction from the main memory

Decoding: It translates instructions into computer commands

Execution: It processes the commands

Storage: It stores the results into the memory

Central Processing Unit (CPU):

CPU is the brain of a computer. It is a part of a computer where the entire work

is performed. The combination of ALU and CU is called as CPU.



Processor Speed:

It is usually measured in Megahertz (Mhz) or Gigahertz (Ghz).

Generations of a Computers:

1. First Generation: Vacuum Tubes (1946 – 1959)

This generation used vacuum tubes as the basic components for memory and

circuitry or CPU.

Input and Output devices:

Punched cards, paper tape and magnetic tapes

Operation system is basically a batch processing

Programming language: Machine Coding

2. Second Generation: Transistors (1959 – 1965)

Primary memory: Magnetic cores

Secondary memory: Magnetic tape and magnetic disk

Advantages:

Cheaper and low power consumption

More compact in size and more reliable

It is faster than Vacuum Tubes

Operating system: Batch processing and Multiprogramming

In this generation assembly language and high-level programming languages

like FORTRAN, COBOL were used.

Classification of Computers:

PC (Personal Computer)

A personal computer (PC) is a small, relatively inexpensive computer designed

for an individual user with less powerful microprocessor.



WorkStation

A desktop computer terminal, typically networked and more powerful than a

personal computer.

Mini Computer

It is a multi-user computer system which is capable of supporting hundreds of

users simultaneously

Main Frame

A data processing system employed mainly in large organizations for various

applications, including bulk data processing.

Supercomputer

It is an extremely fast computer which can execute hundreds of millions of

instructions per second.

3. Third Generation : Integrated Circuits (1965 – 1971)

Integrated Circuits (IC’s) replaced usage of transistors

Single IC consists of basic components like many transistors, resistors and

capacitors along with the associated circuitry.

Advantages:

Smaller in size , reliable and efficient

High level languages: FORTRAN-II TO IV, COBOL, PASCAL PL/1, BASIC,

ALGOL-68

4. Fourth Generation: Microprocessors (1971 – 1980)

It is also called as Very Large Scale Integrated (VLSI) circuits.

A single microprocessor is having about 5000 transistors and other circuit

elements.

High level languages: C, C++, DBASE etc., were used



5. Fifth Generation: Artificial Intelligence (1981 to till date)

The VLSI technology became ULSI (Ultra Large Scale Integration)

The production of microprocessor chips having ten million electronic

components

High level languages: C, C++ , Java, .Net are used

Inclusions:

Robotics

Neural Networks

Game Playing

Development of expert systems to make decisions in real time situations

Some basic orders:

Lowest to highest: Bit, Byte, Character, Field, Record and File

Sequence of Operation in Booting

Load BIOS -> Perform Post -> Load OS -> Check Configuration Settings

Lowest to highest: Bit, Byte, Kilo Byte, Mega Byte, Giga Byte, Tera Byte, Peta

Byte, Exa Byte, Zetta Byte

2. SOFTWARE

There are two types of Softwares.

They are 1. System Software

2. Application Software

1. System Software:

The system software is a collection of programs designed to operate , control

and extend the processing capabilities of the computer itself.

It serves as the interface between hardware and the end users

Examples: Operating System, Compilers, Interpreter, Assembler etc.,



Operating System:

An operating system (OS) is system software that manages computer hardware

and software resources and provides common services for computer programs.

Example: Windows XP and Windows 7

2. Application Software:

It is the set of programs necessary to carry out operations for a specified

application.

Application software can be subdivided into three categories. They are

Packages, Utilities and Customized Softwares.

A. Packages:

Word Processing:

A package that process textual matter and creates organized and flawless

documents.

Spreadsheets

An electronic spreadsheet is a program that accepts data in a tabular form and

allow users to manipulate , calculate, analyze data in the desired manner.

Database Management Systems

DBMS is a package that can handle and manage bulk of stored data.

Desktop Publishing Software

Handles page layout by combining the functions of a traditional typesetter and

a layout artist.

Graphics, Multimedia and Presentation applications

Application software that manipulates images is known as Graphics software

B. Utilities:

Utilities are also a application program

It assists the computer by performing housekeeping functions like

scanning viruses , backing up disk or etc.



Text Editor

This program is used for creating, editing text files.

Backup Utility

This Program facility for the backing-up of disk by archives.

Compression Utility

Large files can be compressed so that it takes less storage area.

Disk Defragmenter

It speeds up disk access by rearranging the files and free space on your

computer.

Antivirus Software

It scans yours disk for viruses and removes them if any virus is found.

C. Customized Software:

This type of software is tailor-made software according to a user’s

requirements.

Software Categories

Freeware:

A software that is available free of cost.

The basic examples of freeware include Skype and Adobe Acrobat Reader.

Shareware

It is software that is distributed free on a trial basis with the understanding

that the user may need or want to pay for it later.

Examples: Trial version of Avast antivirus , games and other softwares

Commercial software

It is any software or program that is designed and developed for licensing or

sale to end users or that serves a commercial purpose.

Examples : MS Office, Windows XP



Open source software

It refers to any program whose source code is made available for use or

modification as users or other developers see fit.

Open source software is usually developed as a public collaboration and made

freely available.

Examples: LINUX and UNIX

Special terms:

Installation is the process of copying software programs from secondary

storage media to the hard disk.

3. COMPUTER HARDWARE

Computer hardware is the physical parts or components of a computer, such

as the monitor, keyboard, computer data storage, hard disk drive (HDD),

graphic cards, sound cards, memory (RAM), motherboard, and so on,

Motherboard

A motherboard is the main printed circuit board (PCB) found in general

purpose microcomputers and other expandable systems.

Microprocessor

A single chip containing all the elements of a computer's CPU.

A hard disk drive (HDD)

It is a data storage device used for storing and retrieving digital information

using one or more rigid rapidly rotating disks (platters) coated with magnetic

material.

Graphics Card

It is responsible for rendering an image to your monitor, it does this by

converting data into a signal your monitor can understand.

Sound Card

A device which can be slotted into a computer to allow the use of audio

components for multimedia applications.



SMPS

A switched-mode power supply is an electronic power supply that includes a

switching regulator to convert electrical power efficiently and effectively.

Input Devices:

Keyboard

Mouse

Joystick

Scanner

Microphone

Touch Screen as well as Output

Microphone

Magnetic Ink Card Reader

Optical Character Reader

Bard Code Reader

Output Devices:

Visual Display Unit (VDU) or Monitor

Printers

Projector

Speaker

Plotter

Peripheral Devices:

Hardware that are connected externally are called peripherals. The basic

examples are keyboards, USB mouse , Speakers, Monitor etc., The computer is

able to work without the need of peripherals

Memory Management:

Types of Memory

Primary

Secondary Memory



Primary Memory:

It holds the data and instruction on which computer is currently working.

It is also called as main memory and volatile memory

It is faster than Secondary Memory

Two types of Primary Memory

1.RAM (Random Access Memory)

2.ROM (Read Only Memory)

1. RAM (Random Access Memory)

All the active data and programs are stored in RAM. So, they readily available

and easily accessible by the CPU

It is a volatile memory

Two types of RAM

Static RAM

In this the memory retains its contents as long as power remains applied

Dynamic RAM

It must be continually refreshed in order for it to maintain the data

2. ROM (Read Only Memory)

The storage of data in ROM is permanent.

It is a non volatile memory

It is more reliable and cheaper than RAM

Types of ROM

i. MROM (Masked ROM)

ii. PROM (Programmable Read Only Memory)

iii. EPROM (Erasable and Programmable Only Memory)



The content in EPROM is erased only by exposing in Ultraviolet Radiation upto

40 minutes.

iv. EEPROM (Electrically Erasable and Programmable Only Memory)

Secondary Memory:

It is also a permanent storage of data and information

It is non-volatile memory

It is not directly accessible to CPU.

Transformation of information from the secondary memory to the primary

memory first and then to the CPU

Examples Of Secondary Memory:

Magnetic Tape, Floppy Disk and Hard Disk

Virtual Memory

It is a memory on the hard disk that the CPU uses the extended RAM.

Cache Memory:

It is a small sized type of volatile computer memory

It provides high speed data access to a processor

It stores frequently used computer programs, applications and data

Data storage is temporary

It has limited capacity and very expensive

Uninterrupted Power Supply (UPS)

A battery powered backup system that provides enough electricity to a

computer during a power outage so that a user can save files before shutting

down the computer.

Accumulator:

A local storage area called a Register, in which the result of an arithmetic or

logic operation is formed.



4. COMPUTER NETWORK

A computer network is a group of two or more computer systems linked

together.

Local Area Network

A local area network (LAN) is a group of computers and associated devices that

share a common communications line or wireless link to a server.

LANs can be built with relatively inexpensive hardware, such as hubs, network

adapters and Ethernet cables.

Metropolitan Area Network

A metropolitan area network, or MAN, consists of a computer network across

an entire city, college campus or small region. A MAN is larger than a LAN,

which is typically limited to a single building or site.

Personal Area Network

A personal area network, or PAN, is a computer network organized around an

individual person within a single building.

This could be inside a small office or residence. A typical PAN would include

one or more computers, telephones, peripheral devices, video game consoles

and other personal entertainment devices.

Wide Area Network

A wide area network, or WAN, occupies a very large area, such as an entire

country or the entire world.

A WAN can contain multiple smaller networks, such as LANs or MANs. The

Internet is the best-known example of a public WAN.

Network Topology:

a. BUS Topology

Bus topology is a network type in which every computer and network device

is connected to single cable. When it has exactly two endpoints, then it is

called Linear Bus topology.



Features of Bus Topology

It transmits data only in one direction.

Every device is connected to a single cable

Advantages of Bus Topology

It is cost effective.

Cable required is least compared to other network topology.

b. RING Topology

It is called ring topology because it forms a ring as each computer is

connected to another computer, with the last one connected to the first.

Exactly two neighbors for each device.

Features of Ring Topology

The transmission is unidirectional, but it can be made bidirectional by having

2 connections between each Network Node, it is called Dual Ring Topology.

Data is transferred in a sequential manner that is bit by bit.

Advantages of Ring Topology

Transmitting network is not affected by high traffic or by adding more nodes,

as only the nodes having tokens can transmit data.

Cheap to install and expand

Disadvantages of Ring Topology

Troubleshooting is difficult in ring topology.

Adding or deleting the computers disturbs the network activity.

c. STAR Topology

In this type of topology all the computers are connected to a single hub

through a cable.

This hub is the central node and all others nodes are connected to the central

node.



Features of Star Topology

Every node has its own dedicated connection to the hub.

Hub acts as a repeater for data flow.

Can be used with twisted pair, Optical Fibre or coaxial cable.

Advantages of Star Topology

Fast performance with few nodes and low network traffic.

Hub can be upgraded easily.

Easy to troubleshoot.

d. TREE Topology

It has a root node and all other nodes are connected to it forming a hierarchy.

It is also called hierarchical topology. It should at least have three levels to the

hierarchy.

Features of Tree Topology

Ideal if workstations are located in groups.

Used in Wide Area Network.

Advantages of Tree Topology

Extension of bus and star topologies.

Expansion of nodes is possible and easy.

Disadvantages of Tree Topology

Heavily cabled.

Costly.

e. HYBRID topology

Hybrid topology is an integration of two or more different topologies to

form a resultant topology which has many advantages of all the constituent

basic topologies rather than having characteristics of one specific topology.

f. MESH Topology



It is a point-to-point connection to other nodes or devices. All the network

nodes are connected to each other.

Mesh has n(n-2)/2 physical channels to link n devices.

There are two techniques to transmit data over the Mesh topology, they are :

Routing - Routing logic to direct the data to reach the destination using the

shortest distance.

Flooding - The same data is transmitted to all the network nodes, hence no

routing logic is required.

5. INTERNET:

Internet

The Internet is a global system of interconnected computer networks that use

the standard Internet protocol suite (TCP/IP) to link several billion devices

worldwide.

It also known as “network of networks”.

World Wide Web

The World Wide Web commonly known as the Web is a system of interlinked

hypertext documents that are accessed via the Internet.

Web Browser

A web browser is a software application for retrieving, presenting and

traversing information resources on the World Wide Web.

Hyperlink

A link from a hypertext document to another location, activated by clicking on

a highlighted word or image.

A hyperlink, or simply a link, is a reference to data that the reader can directly

follow either by clicking, tapping, or hovering followed by automatically.

Downloading

Download is to receive data from a remote system, typically a server such as

a web server, an FTP server, an email server, or other similar systems.



Typically, downloading is the process of copying of files from the Internet.

URL

URL means Uniform Resource Locator. It serves major role to identify

particular resources in the world wide web.

Uploading

Uploading refers to the sending of data from a local system to a remote system

such as a server or another client

Website

A website is a set of related web pages served from a single web domain.

IP address

A unique string of numbers separated by full stops that identifies each

computer using the Internet Protocol to communicate over a network.

Domain Name System

The Internet's system for converting alphabetic names into numeric IP

addresses. Domain Name System (or Service or Server), an Internet service

that translates domain names into IP addresses.

E-mail

Messages distributed by electronic means from one computer user to one or

more recipients via a network. The first email was sent by Ray Tomlinson to

himself in 1971

Email attachment

An email attachment is a computer file sent along with an email message.

Spam

Irrelevant or unsolicited messages sent over the Internet, typically to large

numbers of users



Phishing

Phishing is the attempt to obtain sensitive information such as usernames,

passwords, and credit card details, often for malicious reasons, by

masquerading as a trustworthy entity in an electronic communication.

Hot mail

It is a free email service provided by Microsoft which was established in

1995.

It was co – founded by Indian American Entrepreneur Sabeer Bhatia along with

Jack Smith in 1996.

Domain Name

The part of a network address which identifies it as belonging to a particular

domain. Domain names are used to identify one or more IP addresses.

HTML

HTML stands for Hyper Text Markup Language. HTML is the standard markup

language for creating Web pages.

ISP

ISP is Internet Service Provider. That is the private company or government

organization that plugs into the vast Internet around the world.

Bookmark

A bookmark is a saved link to a Web page. It is also called as favorites or

Internet shortcuts in Internet Explorer.

Cookies

A message given to a Web browser by a Web server. The browser stores the

message in a text file. The message is then sent back to the server each time

the browser requests a page from the server.

Whaling

Whaling involves a web page or email that masquerades/pretence as being

legitimate and urgent.



Spooling

Spooling is a specialized form of multi-programming for the purpose of

mediating between a computer application and a slow peripheral, such as a

printer.

Email spoofing

Email spoofing is the creation of email messages with a forged sender address.

Hacktivism

Hacktivism is the subversive use of computers and computer networks to

promote a political agenda.

HTTP 404

The 404 or Not Found error message is a Hypertext Transfer Protocol (HTTP)

standard response code in computer network communications.

Universal Serial Bus (USB)

A common standard for connecting multiple peripherals to a computer as

needed.

Internet telephony

An Internet telephony service provider (ITSP) offers digital telecommunications

services based on Voice over Internet Protocol (VoIP) that are provisioned via

the Internet.

6. COMMUNICATION PROTOCOLS:

PROTOCOL

A set of rules and regulations that coordinates the exchange of information

over the network.

TCP/IP

TCP/IP, Transmission Control Protocol/Internet Protocol, is a suite of

communications protocols used to interconnect network devices on the

Internet.



TCP/IP implements layers of protocol stacks, and each layer provides a well-

defined network services to the upper layer protocol.

UDP

UDP (User Datagram Protocol) is an alternative communications protocol to

Transmission Control Protocol (TCP) used primarily for establishing low-latency

and loss tolerating connections between applications on the Internet.

POP

Post Office Protocol (POP) is a type of computer networking and Internet

standard protocol that extracts and retrieves email from a remote mail server

for access by the host machine.

FTP

The File Transfer Protocol (FTP) is a standard network protocol used to transfer

computer files between a client and server on a computer network.

FTP is built on a client-server model architecture and uses separate control

and data connections between the client and the server.

HTTP

HTTP (Hypertext Transfer Protocol) is the set of rules for transferring files (text,

graphic images, sound, video, and other multimedia files) on the World Wide

Web.

HTTPS

HTTPS is a protocol for secure communication over a computer network which

is widely used on the Internet.

ICMP

The Internet Control Message Protocol (ICMP) is one of the main protocols of

the internet protocol suite. It is used by network devices, like routers, to send

error messages indicating, for example, that a requested service is not available

or that a host or router could not be reached.



IMAP

In computing, the Internet Message Access Protocol (IMAP) is an Internet

standard protocol used by e-mail clients to retrieve e-mail messages from a

mail server over a TCP/IP connection. IMAP is defined by RFC 3501.

Router

The hardware device or software program that sends messages between

networks is known as Router.

Bandwidth:

The amount of data that can be transmitted in a fixed amount of time. It is

usually expressed in bits per second (bps) or bytes per second.

Serial Port

An outlet on a computer used to attach a device, such as a modem. A serial

port sends data (bits) down the wire one at a time (in a series).

Modem

Modem (Modulator –DE Modulator): Modem is a device attached to computers

that can convert digital signals to analog signals and vice versa for

communication via telephone cables.

Router

A router is a networking device that forwards data packets between computer

networks. Routers perform the traffic directing functions on the Internet.

Network Interface Card

A network interface card (NIC) is a circuit board or card that is installed in a

computer so that it can be connected to a network. NIC is also referred to as an

Ethernet card and network adapter. It is an expansion card that enables a

computer to connect to a network.

GPS

GPS or Global Positioning System is a network of orbiting satellites that send

precise details of their position in space back to earth.



The signals are obtained by GPS receivers, such as navigation devices and are

used to calculate the exact position, speed and time at the vehicles location.

CDMA

CDMA is an example of multiple access, where several transmitters can send

information simultaneously over a single communication channel. This allows

several users to share a band of frequencies.

Bandwidth

Bandwidth is the total maximum transfer rate of a network cable or device. It is

usually measured in bits per second.

GSM

GSM (Global System for Mobile communications) is an open, digital cellular

technology used for transmitting mobile voice and data services.

Gateway

The gateway is the computer that routes the traffic from a workstation to the

outside network that is serving the Web pages.

A machine that links two networks using different protocols is also called as

gateway.

In homes, the gateway is the ISP that connects the user to the internet.

Server

A computer or computer program which manages access to a centralized

resource or service in a network.

DSL

DSL Stands for "Digital Subscriber Line." It is a communications medium used

to transfer digital signals over standard telephone lines.

ADSL

Asymmetric digital subscriber line (ADSL) is a type of digital subscriber line

(DSL) technology, a data communications technology that enables faster data

transmission over copper telephone lines rather than a conventional voice band

modem can provide.



Telnet

A protocol for remote computing on the internet that allows a computer to act

as a remote terminal on another machine, anywhere on the internet.

Hub

A network device that connects multiple computers on a LAN so that they can

communicate with another network and the Internet

Gopher

A protocol used for locating and transferring information on the internet. It is

an internet search tool that allows users to access textual information.

PCI

Peripheral Component Interconnect is an interconnection system between a

microprocessor and attached devices in which expansion slots are spaced

closely for high speed operation.

Open system interconnection model (OSI)

It is a conceptual model that characterizes and standardizes the internal

functions of a communication system by partitioning it into abstraction layers.

Seven layers of OSI model

Application Layer

Presentation Layer

Session Layer

Transport Layer

Network Layer

Data link Layer

Physical Layer

7. PROGRAMMING LANGUAGES:

Program

The set of instructions, which controls the sequence of operations, are known

as Program.



Assembler

The assembly language program is translated into machine code by a separate

program known as an Assembler

Spoofing attack

It is a situation in which one person or program successfully represents oneself

as another by falsifying data and thereby gaining an illegitimate advantage.

Command

An instruction that causes a program or computer to perform a function

Debugging

Debugging is the checking and correcting of errors in a program.

Interpreter

This language processor converts a HLL (High Level Language) program into

machine language by converting and executing it line by line.

Compiler

It also converts the HLL program into machine language but the conversion

manner is different. Multitasking. The ability of a computer to execute more

than one program at a time.

8. SECURITY

Antivirus Software

Antivirus or anti-virus software is computer software used to prevent, detect

and remove malicious software. This software was originally developed to

detect and remove computer viruses.

Virus

A piece of computer code designed as a prank or malicious act to spread from

one computer to another by attaching itself to other programs.

Macro virus

A type of virus that attaches itself to documents or word processing templates.



Piracy

It is an illegal copying of software or other creative works.

Password

A user’s secret identification code, required to access stored material. A

procedure intended to prevent information from being accessed by

unauthorized persons.

Malware

Software that disrupts normal computer functions or sends a user’s personal

data without the user’s authorization.

Firewall

A security system usually consisting of hardware and software that prevents

unauthorized persons from accessing certain parts of a program, database or

network.

Authorization

It is the function of specifying access rights to resources related to information

security and computer security in general and to access control in particular.

Authentication

It is an act of confirming the truth of an attribute of a single piece of data or

entity. It often involves verifying the validity of at least one form of

identification.

Cloud computing

Delivery of storage or computing services from remote servers online (ie via the

internet).

Encryption

The transformation of data to hide its information content.

Hacker

Someone who violates computer security for malicious reasons, kudos or

personal gain.



Network firewall

Device that controls traffic to and from a network.

Outsourcing

Obtaining services by using someone else’s resources.

Proxy server

Server that acts as an intermediary between users and others servers,

validating user requests.

Spyware

Malware that passes information about a computer user’s activities to an

external party.

Threat

Something that could cause harm to a system or organization.

Vulnerability

A flaw or weakness that can be used to attack a system or organization.

Worm

Malware that replicates itself so it can spread to infiltrate other computers.

Screen scraper

A virus or physical device that logs information sent to a visual display to

capture private or personal information.

Intrusion prevention system (IPS)

Intrusion detection system that also blocks unauthorized access when

detected.

Inspection certificate

A declaration issued by an interested party that specified requirements have

been met.



Identification

The process of recognizing a particular user of a computer or online service.

Adware

Ad supported software, often called adware, is used when referencing any type

of software that downloads or displays unwanted advertisement on a computer

while the software is being used.

Crackers

An individual with extensive computer knowledge whose purpose is to breach

or bypass internet security.

Denial of Service (DoS) Attack

A denial-of-service (DoS) attack involves an attempt to disrupt the normal

functioning of a website or web service.

Exploit

An exploit is the use of software, data, or commands to “exploit” a weakness in

a computer system or program to carry out some form of malicious intent, such

as a denial-of-service attack.

Key logger

A key logger, also known as keystroke logging or key logging, is a method of

tracking the strokes on a keyboard without the knowledge of the user.

Spear-phishing

Spear-phishing defines a more specialized phishing scheme targeting a specific

employee in order to gain access to a company’s information.

Trojan

A shortened form of "Trojan Horse", this type of malware appears to have a

legitimate or at least benign use, but masks a hidden sinister function.

Patch

A patch is an update to a vulnerable program or system.



Drive-by Download

These attacks exploit vulnerabilities in your browser or its plug-in and helper

applications when you simply surf to an attacker-controlled website.

Plug in

Plug-in or Ad on is a software component that adds a specific feature to an

existing computer program.

They are simply extensions that extends the usability of the program.

9. INTRANET AND EXTRANET

Intranet

An intranet is a network based on TCP/IP protocols (an internet) belonging to

an organization, usually a corporation, accessible only by the organization’s

members, employees, or others with authorization.

Secure intranets are now the fastest growing segment of the Internet because

they are much less expensive to build and manage than private networks based

on proprietary protocols.

Extranet

An extranet is a website that allows controlled access to partners, vendors and

suppliers or an authorized set of customers – normally to a subset of the

information accessible from an organization’s intranet.

10. MICROPROCESSORS AND MICROCONTROLLERS

About Microprocessors:

A microprocessor is a general purpose device which is called a CPU.

A microprocessor do not contain on chip I/O Ports, Timers, Memories etc.,

Microprocessors are most commonly used as the CPU in microcomputer

systems.

Microcontroller – 8051

A microcontroller is a dedicated chip which is also called single chip computer



A microcontroller includes RAM, ROM serial and parallel interface, timers and

interrupt circuitry in a single chip.

Microcontroller based system design is rather simple and cost effective.

Salient Features

4 KB on chip program memory (ROM or EPROM)

128 bytes on chip data memory (RAM)

8 – bit data bus

16 – bit address bus

32 general purpose registers each of 8 bits

Two – 16 bit timers T0 and T1

Five interrupts (3 internal and 2 external)

Four parallel port each of 8 – bits with a total 32 I/O lines

One 16 – bit program counter

One 8 – bit stack pointer

One Microsecond instruction cycle with 12 MHZ crystal

One full duplex serial communication port

******

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