4 44 CHAPTER The System Unit

4 © The McGraw-Hill Companies, Inc Competencies 1. Basic Components and Types 2. Coding 3. Memory -- Chips 4. Cards and Buses 5. Ports and Cables

4 © The McGraw-Hill Companies, Inc Basic Components Computing power System unit Basic principles

4 © The McGraw-Hill Companies, Inc Basic Types DesktopDesktop NotebookNotebook Personal Digital AssistantPersonal Digital Assistant

4 Coding Electronic Data and Instructions Binary –0s and 1s –8 bits = 1 byte

4 © The McGraw-Hill Companies, Inc System Board Connects all components Allows communication between devices Main board or motherboard Circuit board w/sockets and chips

4 Microprocessor CPUCPU – control unit – arithmetic and logic unit

4 Memory RAM RAM – holds programs and data ROM ROM – fixed start-up instructions CMOS CMOS – flexible start-up instructions

4 © The McGraw-Hill Companies, Inc RAM cache Frequently accessed Acts as high-speed, temporary holding area Faster processing results

4 © The McGraw-Hill Companies, Inc Memory Measure UnitCapacity Kilobyte (KB)1,000 bytes Megabyte (MB)1 billion bytes Gigabyte (GB)one million bytes Terabyte (TB)one trillion bytes

4 © The McGraw-Hill Companies, Inc System Clock Controls speed Synchronizes operations Expressed in megahertz Faster clock speed, faster computer

4 Expansion Slots and Cards Open architecture Network connections PC/TV combinations

4 © The McGraw-Hill Companies, Inc Also Known As Expansion cards (plug-in boards) Controller cards Adapter cards Interface cards

4 © The McGraw-Hill Companies, Inc Kinds Available NICs SCSI adapter Television boards PC/TV combo cards PC cards PCMCIA cards

4 © The McGraw-Hill Companies, Inc “Plug and Play” System notification Check for latest drivers

4 © The McGraw-Hill Companies, Inc Bus Lines Data roadway for traveling bits More lanes, faster traffic –64 bit bus faster than a 32 bit

4 © The McGraw-Hill Companies, Inc Three Principal Architectures Industry Standard Architecture (ISA) Peripheral Component Interconnect (PCI) Advanced Graphic Port (AGP)

4 © The McGraw-Hill Companies, Inc Ports Connecting socket Four common ports –Serial –Parallel –USB –FireWire

4 © The McGraw-Hill Companies, Inc Cables Connect IO devices Most common –Mouse –Keyboard –Printer –Monitor Newer cables –AGP – graphics monitor –USB – joy stick; scanner –HPSB – video camera

4 © The McGraw-Hill Companies, Inc ComponentFunction System boardVarious system components MicroprocessorCPU on single chip MemoryPrograms and instructions System clockSpeed of operations Expansion slots/boardsExpansion of capabilities Bus linesConnect components PortsConnect outside devices

4 © The McGraw-Hill Companies, Inc Look to the Future Intel’s Mobile Module Xircom notebook

4 © The McGraw-Hill Companies, Inc Questions / Comments Thank U