SYSTEM UNIT

Amy PierceComm. 165

MWF 800-850

System unit components are housed within the system unit or system cabinet

• Desktop• Notebook• PDA (personal digital

assistant)

ELECTRONIC REPESENTATION• Data and

instructions are represented electronically with a two-state binary system or numbers

• A byte consists of eight bits and represents one character.

BINARY CODING SCHEMES

• ASCII• EBCDIC• Unicode

SYSTEM BOARD

• Also known as the main board or mother board

• Connects all system components

• a flat circuit board covered with sockets and other electronic parts, including a variety of chips

MICROPROCESSORThe “brains” or the system unit

• Control Unit• Arithmetic-logic

unit• Microprocessor

chips– Word

• complex instruction set computer chips

• reduced instruction set computer chips

– Smart cards

MEMORY

• RAM– flash RAM – virtual memory– memory cache

• ROM• CMOS

SYSTEM CLOCK

The system clock controls the speed of computer operations. It is measured in gigahertz.

EXPANSION SLOTS AND CARDS

• Network adapter cards• modem cards• television boards• PC cards

BUS LINES

• ISA• PCI• AGP• USB

PORTS AND CABLES

• Allow external devices to connect to the system unit

• Ports - connection sockets on the outside of the system unit– types: serial, parallel, USB, and HPSB

• Cables - used to connect external devices to the unit via ports

Thank You