Microprocessor (Introduction to Computer Continued)

The Microprocessors:-

The Microprocessor is the brain of computer. A microprocessor is is an integrated circuit that contains a complete CPU on a single chip. It is simply called CPU. CPU is central component of computer. The processor performs the calculations and processing for the computer. There are 2 main units of a Computer Processor.
Arithmetic and Logic Unit
Control Unit

Arithmetic and Logic Unit:-
This Part of the CPU. All the operation of Arithmetic and logic are Performed by ALU. The data on which any operation is to be taken is fed to computer memory with the help of Input device. That is then assigned to ALU for further operations. ALU is actually combination of two units.
Arithmetic Unit
Logic Unit

Arithmetic Unit:-

The Arithmetic unit of ALU performs the fundamental operation of arithmetic such as addition, subtraction, multiplication and division.

Logic Unit:-

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

Control Unit:-

CU is responsible for the execution of the program instruction given to the computer.The Input and Output Devices also depend on the CU.
It accepts the data from input devices and transfer it to the main memory. Then it transfer data from the main memory to ALU. At the end it sends the output either to main memory or output devices.

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