Microprocessor Introduction: (continued)

Arithmetic and logic unit:

  It is part of CPU. ALU performs all the operations of arithmetic and logic are performed by ALU. The data on which any operation is to be taken is fed into the computer memory with the help of input devices. The data is then assigned to ALU for further operation. ALU may further be divided into two parts:
Arithmetic Unit
Logic Unit

Arithmetic Unit:

The arithmetic unit of ALU performs the fundamentals operations of arithmetic such as addition, subtraction, multiplication, and division.

Logic Unit:

 unit of ALU does all the operation of data involving between two values. The logical operations include the comparison between two numbers to define which number is greater, less equal or not equal to the number.

Control Unit:

CU is responsible for the execution of the program instruction given to the computer. The input and output devices also depend upon the CU.
It accepts data from the input devices and transfers it to the main memory. Then it transfers data from the main memory to ALU. In the end it sends the output either to the main memory or output devices.

Microprocessor Introduction:

Microprocessor Introduction:

A microprocessor is an integrated circuit that contains a complete CPU on a single chip. It is also called the brain of computer. The microprocessor is also called CPU. CPU is central component of pc. The processor performs calculations and processing for the pc. CPU interacts with main memory Ram and other components of the computer. CPU is used in microcomputers as a compulsory component.
As for as the working of the CPU is connected, it is divided into two units:

1. Arithmetic & logic unit (ALU)
2. Control unit (CU)

Components of Computer

Components of Computer:-

Basically, a computer consists of four components

1. Hardware: The physical or tangible parts of the computer called hardware. Like Monitor, Keyboard, CPU, Mouse etc. 
2. Software: The set of instructions, that tells the computer, what to do and how to do.
3. Data: A collection of raw facts and figures is called data, which can include text, numbers, images, audios and videos etc.
4. User: Computer cannot do any without its operator.

Memory Unit (MU)

Memory Unit:-

Memory unit that is also called Main Memory or Random Access Memory is the Primary Unit of the computer. The computer cannot start without Main memory. Main memory is directly accessible by CPU of the computer. The data is stored in main Memory before and after processing. It is a volatile Memory it means it only stores data when computer is turned on.

When we start a computer data from Hard disk is loaded in RAM. The most part of RAM is used by Operating System of the Computer. Remaining Main Memory is distributed between application software.

The Capacity of main memory is measured in Bytes. RAMs are available in GB (Gigabytes).

The Central Processing Unit (CPU)

The Central Processing Unit:-

The Central Processing Unit or CPU is also called the Brain of a Computer. It is a very complex integrated Circuit. It is build up of millions of tiny components integrated together. It is mainly divided into 2 units.
Arithmetic and Logic Unit (ALU)

Control Unit (CU)

Arithmetic and Logic Unit (ALU):-
The arithmetic and logic unit is the place where main processing is done. It performs Arithmetic Calculation (addition, subtraction, multiplication and division), while Logic unit performs Logical computations (compare objects and numbers with logical statements. Hence ALU manipulates the data.

Control Unit (CU):-

Control Unit maintains, orders and Controls the processing activity in the CPU. It directs the sequence of Operations.

Branded and Un-branded Computer (availability of Computers)

Availability of Computers:-

Computers available in market can be categorized in two groups. Branded Computers and Un-branded Computers.

Branded Computers:-

These Computers are marked under a brand name. It means some company assemble these computers under its trade name and sale it to end-users. For example IBM, APPLE, ACER, COMPAQ, HP, DELL etc. These computers are high in quality and cost as well.

Un-branded Computers:-

These computers have no brand name or trade name of seller. These computers are usually made in Taiwan and Korea. Or some time local sellers assemble different parts together to sale them as computers. These are are cheap computing machine and less reliable then Branded computers.

Classification of Computers

Classification of Computers:-

Computers are classified according to their size, Technology and Working Principle into following different categories. 

Depending upon their Size

Super Computer

Mainframe Computer

Mini Computers

Microcomputers

Depending upon their Working Principle

Analogue Computers

Digital Computers

Hybrid Computer

Depending Upon their Technology (Generations of Computer)

First Generation of Computer (1945-1959)

Second Generation of Computer (1959-1965)

Third Generation of Computer (1965-1971)

Forth Generation of Computer (1971-Present)

Fifth Generation of Computer (Future)

Characteristics of Computer

Characteristics of Computer:-

The Characteristics of Computers can be defined in the terms of what it can do and wht it can't do? Following are some Characteristics of Computers.

SPEED :

The computer is very fast machine. It can do any task in millionth part of a second. It can process millions of instruction per seconds MIPS. Modern computers can process Trillion of Instructions per second TIPS.

ACCURACY :

The results produced by computers are 100% accurate. The accuracy of computer depends on the accuracy of software and given input.

STORAGE :

The other Characteristics of Computer is storing large amounts of data. It can store up to Terabytes of data. This data can be in form of text, books, audios and videos.

DILIGENCE :

Computer never feel sick or need a break like humans. It can perform a given task thousands of times and never feel bored,

VERSATILITY :

Computer is a versatile machine it can do two totally different tasks at the same time with 100% accuracy.

POWER OF REMEMBERING :

Computer have power to remember its work. It can store a task and provide it back to user when ever it is demanded.

NO IQ :

A computer is dumb gadget. It has no idea of its own. It is totally dependent on human as far as concerned about IQ.

NO FEELING :

A computer has no feeling like human. It didn't know about love, hunger, sadness etc. It is just a collection of parts,

Reliability :

A computer is a reliable machine. It produce results according  to given instructions and inputs. It does not add its own ideas in the output.

Automation:

A computer is automatic machine. Many computers only need first time run and then they keep doing their work without any interruption or help

Flexibility:

A computer is a flexible machine. It can do a variety of tasks. It can play songs, Brows internet or perform complex engineering calculation. It is the requirement of user what to do computer is good with all tasks.

Output Devices

Output Devices:-

These devices are used to take output from computer.

• Display Devices
• Printers
• Plotters
• Speakers

Display Devices:-

Display devices are most common output devices now a days. a normal computer always have a display unit like CRT, LCD or LED attached with it. This display unit help user to see what is going inside a computer. With the use of GUI in operating systems the use of advanced display devices is increasing.

Printers:-

Printers are also popular output devices. Printers give the output in printed form on a page. This device is most widely used in banks, offices and other institutions to take prints of documents. Printers are available in color and black & White formats. The printers are divided into two categories.

Impact Printers
Non-Impact Printers

Impact Printers use punching or stroking technology while Non-Impact Printers use liquid or powder ink to print documents.

Plotters:-

plotters are large printers used for printing large pages. Plotters can print hundred feet large documents easily. Plotters most commonly use a special printing material called panaflex. Plotters can also print color as well as black & white documents.

Speakers:-

Speakers are used to take output in form of Sounds and audio. The user can listen songs, audio CDs and tracks using output audio. The computer also inform users about errors using sounds. Some time computer errors are diagnostic by the number of beeps generated by the computer.

Block Diagram of Computer

Units of Computer

Basic Units of Computers:-

According to the definition of computer we learn that computer works in an order to complete tasks. It takes Input, Process Data, Shows Output as results and Store data (Temporarily and Permanently).

So We can say that a computer has five basic units in it.

1. Input Unit
2. Memory Unit (Temporary Storage)
3. Processing Unit
4. Output Unit
5. Storage unit (Permanent Storage)

Input Unit:-

This unit is used to give instructions to Computer. It consist of some Keyboard and pointing devices. All the data and Instruction are given to computer through this unit. The devices used to give data and instructions to computer are called input devices.

Memory Unit:-

This unit works as an interpreter between input, processing and output unit. Data and instructions are stored in Memory unit before and after processing. It is a temporary memory because it only store data when computer is power on. All data is lost when power fails or computer is shutdown. RAM (Random Access Memory) is basic part of Memory Unit. Its size is measured in MB (Megabytes) or GB (Gigabytes)

Processing Unit:-

The processing unit of a computer consist of a processor. A processor is called the brain of computer. It does all the works and tasks for computer. It takes data from input unit and process it according to the given instructions. Its speed is measured in MHz (Mega Hertz).

Output Unit:-

The output unit of computer shows the user what is going inside the computer. It also shows the final results. With the help of this unit computer asks any thing required from the user. Errors are also displayed through this unit. Devices attached to this unit are called output devices. Printer, Monitor, Speakers are examples of the output devices.

Storage Unit:-

The storage unit consist of Secondary Storage Devices. It stores the data permanently. Secondary storage device store data magnetically, Electrically or e Optically. Magnetic Tape, Floppy Disk, Zip Disk, Hard disk drive, USB Mass Storage, CD, DVD and Blue Ray Disks are examples of storage devices

Computer joke of today

A teacher asked her students what is the sound of a dog?

Student A: Buff, Buff

Teacher and what of CAT?

Student B: Mew Mew

Teacher and what of a mice?

After a while a student stands up and said CLICK CLICK!

Types of Software

Types of Software:-

I have previously mentioned in my post that there are four types of computer software.

1. System Software
2. Application Software
3. Utilities
4. Programming Languages

Now I will try to explain these types in detail in some next posts.

Definition of Computer Software

Definition of Computer Software:-

Sets of programs that are used to communicate with computer are called software. Or the programs that we make in the computer are called software (that we can see but not touch). Languages and Packages like MS Word, MS Excel, Basic & COBOL etc. Computer does nothing unless it is given instruction to perform.

These programs are divided into many types according to the purpose of their use. Basically their are following types of Software.

1. System Software
2. Application Software
3. Utilities
4. Programming Languages

Basic Computer Software hierarchy

Definition of Computer Hardware

Definition of Computer Hardware:-

The physical parts of Computer that we can touch (intangibles) are called computer hardware. These parts include Computer Case, Keyboard, Mouse, Hard-disk Drive, CD-ROM, Monitor, LCD, etc.

Components of a Computer

Computer peripherals

Examples of Harware

Define Computer

Definition of Computer:-

A Computer is an Electronics Device which take data as Input, Process data according to given Instruction. After processing data is shows the calculated Results as Output. It can also Store data for later use.

A Typical Personal Computer

Input Devices

In this lecture i will try to give introduction to some key input devices.

Keyboard:-

Keyboard is a most widely used input device. it is the normal method to input data in computer memory using keyboard. Normally a keyboard have 102 to 108 keys on it. Alphabets, Numbers and some special characters are printed on these keys. There are many layouts of keyboards. QWERTY layout is commonly used now a days. A keyboard have following sets of keys on it.
Alphabetic Keys:   (A to Z)
Numeric Keys:       (0 to 9)
Function Keys:       (F1 to F12)
Special Keys:         (ALT, CTRL,DEL, SHIFT etc.)
Special function keys:   (PG-UP, PG-DN, END, HOME, DELETE, PRINT Scr etc.)
Multimedia Keys:   (Forward, Play, Pause, Stop, next, etc. and some internet keys)
Arrow Keys:

Mouse:-

Mouse is a pointing device. We control movement of pointer on screen with the help of a Mouse. A typical mouse have 2 buttons and a scroll. Now a days some mouse come with extra multimedia buttons. Pressing a mouse button is called a click. Pressing a button twice is called a double click. Left click is normally used to select objects on screen, while right click is used to open a list of commands (Menu). Scroll is used to move pages up and down. In many latest browsers a click using scroll button opens the link in a new tab.