1 Inside the Computer Chapter 6 Copyright Prentice-Hall, Inc. 2001

3-2 Be Informed ! ! Monthly Technology Update And, make good decisions when purchasing a PC.

3-3 Electronic Signals Analog Digital

3-4 Bit By Bit Only 2 states possible Off } Human readable symbols On 1 Off 0 Permanently stored on floppy disk } Positive magnetic field Negative magnetic field Permanently stored on CD-ROM } Pitted Not Pitted Inside the computer’s memory } Electronic pulse present Electronic pulse absent On

Digital Digitizing Data Photos courtesy of Hewlett-Packard Company, Intergraph Corporation, Courtesy of International Business Machines Corporation. Unauthorized use not permitted. Analog

3-6 Encoding Systems “A” is represented by this bit pattern 1 byte= 8 bits “A” is represented by this bit pattern 1 byte= 8 bits A A

3-7 ASCII Chart Please memorize by our next class. Just kidding! Encoding

3-8 PC System Unit Motherboard Processor RAM Expansion Cards StorageDevices Hard Drive Floppy Drive CD-ROM/ DVD Drive

3-9 Motherboard l Electronic circuit board l Chipset l Provides path among u CPU u RAM u Peripherals

3-10 Exploring the Motherboard l Microprocessor l Memory Chips l Electronic Bus l Device Controllers l Expansion Slots/Cards

3-11 Intel Processor Progression l 286, 386, 486 l Pentium® l Pentium® Pro l Pentium® II l Pentium® III l Celeron® l Itanium™ Photo Courtesy of Intel Corporation

3-12 Microprocessor: Computer on a Chip l Primary Functions u Read/Interpret program instructions u Direct the operation of internal components u Control flow of programs/data to RAM l CPU includes: u Control unit u ALU Photo Courtesy of Intel Corporation

3-13 Control Unit & ALU l Control Unit u Decoder u Registers u Instruction register u Program register l Arithmetic Logic Unit u Accumulator

3-14 Everything clear so far????

3-15 Memory Types RAM ROMPROMFlash Cache

3-16 Memory: RAM l Random Access Memory l Direct link to CPU l Holds current data and programs at a RAM address l Temporary/Volatile l Common RAM capacities: 128 MB, 256 MB, 384 MB and 512 MB

3-17 Memory: Types of RAM l SDRAM (Synchronous Dynamic RAM) u Can synchronize itself with the processor l RDRAM (Rambus DRAM) u Newer and more expensive u 6 times faster than SDRAM l Installation u SIMMs: 32-bit data path to CPU (single) u DIMMs: 64-bit data path to CPU (dual) u RIMMs: faster RDRAM chips (use to upgrade)

3-18 Memory: Cache l Faster and more costly than RAM l Much smaller capacity than RAM l Holds next instructions l Increases system throughput

3-19 Memory: ROM l Read Only Memory l Permanent, cannot change l Loads Operating System during boot process l PROM

3-20 Memory: Flash l Type of PROM l Can be changed by user l Non-volatile l Upgrade by downloading software from the Web or disk l No longer need to replace chips or circuit boards

3-21 Storage Capacity l Byte - one character l Kilobyte (KB) bytes l Megabyte (MB) - about 1 million bytes l Gigabyte (GB) - about 1 billion bytes l Terabyte (TB) - about 1 trillion bytes

3-22 What Happens Inside Arithmetic Logic Unit Main memory ControlUnitControlUnit OutputUnitOutputUnit Data flow Instruction flow InputUnitInputUnit Control flow

3-23 Machine Cycle: Making the Rounds l Everything is translated to Machine Language Instruction Time Execution Time Fetch Instruction Execute Instruction Place result in memory Decode Instruction l Machine Cycle = Instruction Time + Execution Time

3-24 Ports 1 bit at a time Slow Mice and modems Long distances 127 peripherals Daisychained Infrared Light waves Printers Short distance 8 bits at a time Fast Printers Short distances 15 peripherals Daisychained

3-25 A Fleet of Buses l Expansion boards are made to fit a particular type of bus l Bus Types: u ISA bus u PCI local bus u SCSI bus u USB bus (hot plug) Serendipitous Surfing: Online Shopping

3-26 Adding Peripherals Expansion Slot Expansion Card Peripheral plugs into port Pins plug into slot Courtesy of ATI Technologies Inc.

3-27 Adding Peripherals l AGP graphics adapter l Sound l Data/Voice/Fax modem l Cable modem l Extra serial and parallel ports l NIC card l Video capture card

3-28 PCMCIA Card U.S. Robotics Mobile Communications Corporation

3-29 Describing the Processor l Word Size u 64-bit for PCs l Processor Speed u MHz, MIPS, FLOPS u 400 MHz to 1 plus GHz for PCs l RAM Capacity u 128 to 512 MB for PCs l Processor Personality

3-30 Processor Design l CISC l RISC l Parallel Processing l Neural Networks

31 End of Chapter 6 Interactive Study Guide Copyright Prentice-Hall, Inc. 2001