chapter-9 internal structure of computer

                                        CHAPTER-9 INTERNAL STRUCTURE OF COMPUTER

System unit

System unit is is a box like case that house is the electronic components of the computer which are used to process data .

The system unit is made of plastic or metal that protects the internal parts(processor ,motherboard, power supply etc.) of the computer.

Motherboard

Motherboard is called system board. it is the main printed circuit board  which contains sockets that accept additional boards. In a personal computer. a motherboard contains the bus ,CPU, and co- processor sockets, memory sockets , keyboard controller and supporting chips.

Register

The CPU contains high-speed storage locations called registers. The register is used to hold the data and instructions temporarily.

Port

It is the interface or point of attachment to the system unit. The back of the system unit contains many ports.

Types of ports

There are three types of ports are as follows-

1. Serial Port 

2.Parallel port 

3.USB(Universal serial bus)

Serial port

Serial port is a socket on computer which is used to connect a modem, mouse ,scanner or other serial devices via the computer's Serial interface.

Parallel port 

Parallel port is  a socket on a computer used to connect a printer or other parallel devices via the computer's parallel interface.

USB(Universal serial bus)

 USB stands for Universal cereal bus up to 127 different pedophile devices with a single connector type can be connected by a USB port mini system units have one or two years be poured to attach multiple devices using a single port. the creator of USB is Ajay Bhatt.

Special purpose ports-

There are some special purpose ports are as follows ..

1394 port

It is similar to the USB port also called fire wire can connect multiple types of devices that require faster data transmission speeds such as digital video cameras, digital VCRs, colour printers, scanners, digital cameras and DVD drivers to a single connector.

MIDI

MIDI stands for musical instrument digital interface, this port is used to to connect the system unit to a musical instrument such as electronic keyboard, guitar extra.

SCSI port

SCS stands for small computer system interface ,this sport is a special high speed parallel port that allows you to attach SCSI peripheral devices such as disk drivers and printers.

IrDA port

Some peripheral devices may not use any cable. Instead, some transmit data via infrared light waves. for these wireless devices to transmit signals to a computer, both the computer and the device must have an IrDA port .

Power supply

Many personal computers plug into standard wall outlet with supply and alternative current of 220 V, this type of power supply is unsuitable for the computer. A personal computer required a direct current ranging from 5 to 12 volts. "The power supply is a component in the system unit that converts the wall outlet AC power into DC power."