Transcript William Sawyer

Hardware: The CPU & Storage
4.1 Microchips, Miniaturization, & Mobility
4.2 The System Unit: The Basics
4.3 More on the System Unit
4.4 Secondary Storage
4.5 Future Developments in Processing &
Storage
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Chapter
4
Microchips, Miniaturization, &
Mobility
 Vacuum Tubes vs. Transistors
 vacuum tube, electron tube, or thermionic valve
or just valve, is a device used to amplify, switch or
modify a signal by controlling the movement of
electrons in an evacuated space.
 Vacuum tubes were the original logic gates of computers
 They looked like light bulbs, were hot, and burned out
like them too
 High failure rates, damaged tubes had to be replaced for
the computer to function
 A transistor is a switch, or gate, that can alternate
between “on” and “off” many millions of times per
second.
 Developed in 1947 by Bell Labs
 The original transistors were 1/100th the size of vacuum
tubes (less power, faster, more reliable too)
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Processor Basics
 Integrated Circuit: An entire
electronic circuit formed on a
single “chip” often made of
silicon
 Microchips: AKA “industrial
rice” Is a tiny piece of silicon
that contains millions of microminiature electronic circuits.
 Store and process data.
 Etched on the chip via the
photolithography process.
 Chip manufactures require very
clean environment.
Die on an Intel Processor
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Processor Basics
 A microprocessor The
miniaturized circuitry of an
entire computer processor on a
single chip.
 Contains the CPU, which
processes data
 Microcontroller or Embedded
Computer
Die on an Intel Processor
 A microprocessor that was
modified for use in a machine
that isn’t a computer.
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The System Unit: The Basics
 Binary System: the basic unit of computing
 Uses just two numbers: 0 and 1
 All data and program instructions in the computer
are represented as binary
 Bit: each 0 or 1 is a bit
 Byte: a group of 8 bits
 Kilobyte: ~1,000 (1,024) bytes
 Megabyte: ~1 Million (1,048,576) bytes
 Gigabyte: ~1 Billion (1,073,741,824) bytes
 Terabyte: ~ 1 Trillion (1,009,511,627,576) bytes
 Petabyte: ~ 1 quadrillion bytes
 Exabyte: ~ 1 quintillion bytes
 All the printed material in the world is ~ 5 exabytes
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The System Unit: The Basics
 Binary coding schemes assign a unique
binary code to each letter
 EBCDIC
 Requires 8 bits per character
 Used for IBM mainframes
 ASCII
 Requires 7 or 8 bits per character, depending on
the version
 8 bit Extended ASCII provides 256 characters
 01000111 -> “G”
 Used for PCs, Unix hosts, Macs
 Unicode
 Requires 16 bits per character
 Handles 65,536 characters
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The System Unit: The Basics
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The System Unit: The Basics
Computer Terms
 Names
 Definitions
1. Shell or opening used for the installation of
electrical equipment.
2. This converts AC to DC to run the computer.
2. Power Supply
3. Surge Protector 3. Protects the computer from being damaged by
power spikes. Plug your computer into one.
4. Voltage
4. Protects a computer against brownouts or low
Regulator
power conditions that happen a lot in summer.
5. Uninterruptible Power Supply. Battery-operated
5. UPS
device that provides power for a time when there
is a blackout.
6. The main system board of the computer.
6. Motherboard
7. Microprocessor 7. The miniaturized circuitry of a computer
processor.
8. Chipset
8. Groups of interconnected chips on the
motherboard that control information flow
between the microprocessor and other system
components connected to the motherboard. 8
1.
Bay
Traditional Microcomputer
Microprocessor
 Intel Type Chips. Have a similar
internal desging and are made to run
PCs.
 Produced by Intel and AMD.
 Motorola Type Chips. Made by
Motorola and later its subsidiary
Freescale Semiconductor for Apple
Macintosh computers (up to and
including the Apple Mac G4).
 G5 Macintoshes use PowerPC family of
processors (Developed by Apple,
Freescale and IBM).
 PowerPC Chips have the advantage
that with certain hardware or software
configurations, a Macintosh can run PC
as well as Mac applications software
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New Microcomputer
Microprocessor
 Intel Processor for Macintosh.
 Why?
 What happened to the software that
ran in PowerPC?
 Is Mac OS going to run on a nonApple computer?
 Multicore Processors. Designed to
let the operating system divide the
work over more than one processor,
with two or more processor “cores” in
a single piece of silicon.
 Single core vs. multicore processors
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Processing Speeds
 System Clock. Controls how fast all the
operations within a computer take place.
 Delivers a steady stream of digital pulses or “ticks”
to the CPU. This “ticks” are called cycles.
 Faster clock speed will result in faster processing
 The faster a CPU runs, the more power it
consumes, and the more heat it generates
 The CPU
 Older CPUs processing speeds are in MegaHertz
 1 MHz = 1 Million ticks per second
 Current CPUs processing speeds are in GigaHertz
 1 GHz = 1 Billion ticks per second
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More on the System Unit
Parts of the CPU
Name
1. Word size
Definition
1. The number of bits the processor can
process at any one time
2. Control unit 2. The part of the CPU that deciphers
instructions and carries them out
3. Arithmetic 3. The ALU performs mathematical and logical
Logic Unit
operations and controls the speed of them
4. Registers 4. High-speed storage areas that temporarily
5. Buses
store data during processing
5. Electrical data roadways used to transmit bits
within the CPU and between CPU and other
motherboard components
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How the CPU Works
 The machine cycle
consists of four
operations: fetching,
decoding, executing, storing
results
The CPU
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The System Unit: The Basics
 The CPU Continued
 Mainframe and minicomputer speed is
measured in MIPS
 MIPS stands for millions of instructions per second
 Workstations perform at 100 MIPS or more
 Mainframes perform at 200 – 1,200 MIPS
 Supercomputer processing speed is
measured in flops
 Flops stands for floating point operations per
second
 IBM’s Blue Gene/L cranks out 70.72 teraflops (tera
14
= trillion) per second
Hardware: The CPU & Storage
4.1 Microchips, Miniaturization, & Mobility
4.2 The System Unit: The Basics
4.3 More on the System Unit
4.4 Secondary Storage
4.5 Future Developments in Processing &
Storage
15
Chapter
4
More on the System Unit
How Memory Works
Memory Chip
1. RAM
Explanation
1. Random Access Memory chips are volatile
and hold:
a. Software instructions
b. Data before & after the CPU processes it
2. ROM
3. CMOS
2. Read only memory
a. Cannot be written on or erased without special
equipment
b. Are loaded at factory with fixed start-up
instructions
3. Complementary Metal Oxide
Semiconductor
a. Powered by a battery
b. Contains time, date, calendar, boot password
4. Flash
4. Nonvolatile memory that can be erased
and reprogrammed more than once
a. Doesn’t require a battery
b. Used in newer PCs for BIOS instructions
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More on the System Unit
Types of RAM
RAM Types
1. DRAM
2. SDRAM
3. SRAM
4. DDRSDRAM
Explanation
1. Dynamic RAM must be constantly
refreshed by the CPU or it loses its
contents
2. Synchronous Dynamic RAM is
synchronized by the system clock
and is much faster than DRAM
3. Static RAM is faster than DRAM and
retains its contents without having
to be refreshed by CPU
4. Double-data rate synchronous
dynamic RAM
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More on the System Unit
Speeding up Processing
 The CPU works much faster than RAM
 So it could sit there waiting for information
 Cache temporarily stores instructions and
data that the processor uses frequently to
speed up processing
 Level 1 cache is part of the microprocessor
 Holds 8 to 256 kb
 Faster than Level 2 cache
 Level 2 cache is SRAM external cache
 Holds 64 kb to 2 Mb
 Level 3 cache is on the motherboard
 Comes on very high-end computers
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More on the System Unit
Speeding up Processing
Method
1. Interleaving
2.
3.
4.
5.
Description
1. CPU alternates communications between
two or more memory banks
Bursting
2. CPU grabs a block of data from memory
instead of retrieving one piece at a time
Pipelining
3. CPU doesn’t wait for one instruction to
complete before fetching its next
instruction
Superscalar
4. The computer can execute more than one
Architecture
instruction per clock cycle
Hyperthreading
5. A technique used in superscalar
architecture in which the OS treats the
microprocessor as though it is two
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microprocessors
More on the System Unit
Ports
Port Type
1. Serial Port
Description
1. Used to transmit slow data over
long distances
a. Sends data sequentially, one bit at a
time
b. Used to connect keyboard, mouse,
monitors, dial-up modems
2. Parallel Port
3. SCSI Port
2. For transmitting fast data over
short distances
a. Transmits 8 bytes simultaneously
b. Connects printers, external disks,
backups
3. Small Computer System Interface
a. Connects up to 7 devices in a daisy chain
b. Transmits data 32 bits at a time
4. USB Port
4. Universal Serial Bus can
theoretically connect up to 127 20
peripheral devices in a daisy chain
More on the System Unit
USB
 Goals
 Be low-cost
 Be able to connect lots of devices
 Be hot swappable
 People hate rebooting because it takes time
 Hot swapping means a device can be
connected/disconnected without rebooting
 Permit plug and play
 Devices are automatically configured when
they are installed – no need to download new
drivers
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More on the System Unit
USB Continued
 Standards
 USB 1.1 – the original standard
 USB 2.0 – the current standard for new PCs
 USB On The Go (OTG) – currently under
development
 Connectors




A – in USB Type 1.1 and 2.0
B – in USB Type 1.1 and 2.0
Mini B – in USB Type 2.0
Mini A – in USB OTG used for smaller
peripherals like cellphones
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More on the System Unit
Specialized Expansion Ports
Port Type
1. FireWire
2. MIDI
3. IrDA
4. Bluetooth
5. Ethernet
Description
1. Intended for devices working with lots of
data
a. Used for camcorders, DVD players, TVs
b. Handles up to 400 megabits per second
2. Musical Instrument Digital Interface
a. Connects musical instruments
b. Used in creating, recording, editing, performing music
3. Infrared Data Association: Infrared ports
used to make a cableless connection
4. Uses short-range radio waves that transmit
up to 30 ft at 721 Kbps
a. Connects computers to printers, keyboards, headsets,
even refrigerators
b. Named after King Harald Bluetooth, son of Gorm, who
united the Norway and Denmark. Ruled 910-940 A.D.
5. The standard for linking all devices in a23
Local Area Network
More on the System Unit
Expansion Cards
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More on the System Unit
Expansion Buses
Bus
1. PCI bus
2. AGP Bus
Description
1. Peripheral Component
Interconnect
a. For high-speed connections
b. 32 or 64 bits wide
c. Typically used for sound cards,
modems, high-speed network
cards
2. Accelerated Graphics Port
a. Twice the speed of PCI bus
b. For Video and 3-D graphics cards
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Secondary Storage
Storage Types
1. Floppy and Zip
disks
5.
6.
7.
1. Removable disks.
a. Floppies store 1.44 MB
b. Zip disks store 100, 250, or 750 MB
2. Made from thin rigid metal covered
with magnetizable substrate. Most
disks have 2 or more platters
Optical disks
3. Removable CDs and DVDs
Magnetic tape
4. Thin plastic tape coated with
magnetizable substance
5. Like a credit card, but contains a
Smart Cards
microprocessor and memory chips
6. Nonvolatile memory – no moving
Flash memory
parts
Online secondary
7. Lets you store data on an online
storage
vendor’s server
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2. Hard disks
3.
4.
Descriptions
Secondary Storage
Hard Disks
 Thin, rigid metal, glass, or ceramic platters
covered with a substance that allows data to be
held in the form of magnetized spots
 The more platters there are, the higher the drive
capacity
 Store data in tracks, sectors, and clusters
 Formatting creates a file allocation table that maps
files to clusters or inodes
 Typical file systems are VFAT & NTFS for Windows, HFS
and ext2 for Unix
 Drive heads ride on .000001” cushion of air, and can
crash!
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 Important data should always be backed up!
Secondary Storage
Hard Disks
 Hard Disk Types:
 External Hard Disks – a freestanding disk
drive
 Removable Hard Disk – inserted into a
cartridge drive on the PC
 Hard Disk Controllers
 EIDE – Enhanced Integrated Drive Electronics
 Supports up to 4 disks at 137 GB per disk
 Marketed as SATA, Fast ATA, Ultra ATA, ATA-2,
ATA/100
 SCSI – Faster than EIDE controllers
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Secondary Storage
Optical Disks
 CDs and DVDs are Optical disks
 Data is written and read using lasers, not a
disk head
 CD-ROM is Compact Disk Read-Only Memory
 CD-R is used for recording only once
 CD-RW is an erasable optical disk that can both
record and erase data over and over again
 DVD is a CD-style disk with extremely high
capacity
 Stores 4.7 or more GB
 DVD-R is used for recording only once
 DVD-RW, DVD-RAM, DVD+RW are reusable DVDs
 Blu-Ray/HD-DVD vs. conventional red laser
disk technology (25 GB)
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Secondary Storage
Flash Memory
 Nonvolatile memory with no moving parts
 But the electronics can wear out
 Available as
 Flash memory cards
 Insert these into a flash port of a camera,
handheld PC, smartphone
 Flash memory sticks
 A form of flash memory that plugs into a
memory stick port
 Flash memory drives
 A finger-sized module of flash memory
 Plugs into the USB port of most PCs and
Macintoshes
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Future Developments in
Processing & Storage
New
Technology
1. M-RAM
2. OUM
3. Nanotechnology
4. Optical
Computing
5. DNA Computing
Description of Processing
Technology
1. Magnetic RAM uses miniscule magnets
rather than electrical charges
2. Ovonic Multiplied Memory stores bits by
generating different levels of low and
high resistance on a glossy material
3. Tiny machines work at a molecular level
to make nanocircuits
4. Uses lasers and light, not electricity
5. Uses strands of synthetic DNA to store
data
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Future Developments in
Processing & Storage
Description of Storage
Technology
New
Technology
1. Higher-density
disks
1. Magnetic disk drives currently
hold 100 GB of data
2. Molecular
electronics
2. Polymer memory creates chips that
store data on plastics
a. Blank CDs are replacing floppy
disks since they hold 650MB and
cost < $1 each
b. DVD disks hold up to 4.7 GB of
data currently
c. Perpendicular recording
technology allows 25% - 100%
more data to be stored on the
same disk
a. Nonvolatile memory
b. Data is stored based on polymer’s
electrical resistance
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