Transcript session 6 Computer Hardware.ppt

PART I
Introduction to the
Foundation of Information
Technologies
Session 6:
Computer Hardware
HUANG Lihua, Fudan University
Management Challenges
1. The centralization versus decentralization debate.
2. The application backlog.
HUANG Lihua, Fudan University
Feb., - July., 2006
Hardware components of a computer
system
HUANG Lihua, Fudan University
Feb., - July., 2006
The Central Processing Unit (CPU)
• Controls other parts of computer
• Arithmetic-logic unit performs principle
logical/mathematical operations
• Control unit coordinates other parts, such as
reading a stored program
HUANG Lihua, Fudan University
Feb., - July., 2006
CPU & PRIMARY STORAGE
PRIMARY
CPU
STORAGE
DATA BUS
ADDRESS BUS
CONTROL BUS
INPUT
OUTPUT
SECONDARY
DEVICES
DEVICES
STORAGE
HUANG Lihua, Fudan University
Feb., - July., 2006
CENTRAL PROCESSING UNIT
(CPU)
CONTROL UNIT
ROM
ARITHMETIC/LOGIC
UNIT
CLOCK
RAM
PRIMARY (MAIN) MEMORY
HUANG Lihua, Fudan University
Feb., - July., 2006
计算机中的数据处理过程：
机器指令和机器周期
机器指令：
指令周期
2、指令翻译
3、把指令放到寄存器中
4、把地址放到寄存器中
1、取机器指令
8、把结果送到累加器中
7、ALU执行操作
5.20
5、把数据从内存
中取到寄存器中
6、命令ALU执行相应的操作
执行周期
HUANG Lihua, Fudan University
Feb., - July., 2006
The CPU
• CPU = Central Processing Unit
• Instruction execution is automatic
–
–
–
–
–
–
(tick) find memory address of next instruction
(tick) retrieve instruction from memory
(tick) decode the instruction
(tick) fetch argument from memory if necessary
(tick) execute instruction
(tick) store result in memory if necessary
• Internal clock ticks very fast (e. g., 100MHZ
= 100 million ticks per second)
– activities are synchronized to start on a clock tick
– some activities take more than one clock tick
HUANG Lihua, Fudan University
Feb., - July., 2006
COMPUTER TIME
NAME
Millisecond
LENGTH
.001 second
# PER
SECOND
COMPARED
TO 1 SECOND
thousand 15min 40 sec
Microsecond .001 millisecond
million
11.6 days
Nanosecond .001microsecond
billion
31.7 years
Picosecond
trillion
31,700 years
.001 nanosecond
HUANG Lihua, Fudan University
Feb., - July., 2006
Primary Storage
•
•
•
•
•
•
Located near CPU
Stores all or part of active software program
Stores operating system software
Stores data the program is using
Composed of semi-conductors
RAM (random access memory): Used for shortterm, temporary storage
• ROM (read-only memory): Semiconductor
memory chips with program instructions
HUANG Lihua, Fudan University
Feb., - July., 2006
TYPES OF MEMORY
• RAM: Random Access Memory
– Dynamic: Changes thru processing
– Static: Remains constant (power on)
• ROM: Read Only Memory (preprogrammed)
– PROM: Program can be changed once
– EPROM: Erasable thru ultraviolet light
– EEPROM: Electrically erasable
*
HUANG Lihua, Fudan University
Feb., - July., 2006
The CPU and primary storage
HUANG Lihua, Fudan University
Feb., - July., 2006
Microprocessors
• Semiconductor chips integrate memory, logic, and
control circuits for entire CPU
• Speed depends on number of bits processed at one
time; amount of data that can be moved between
devices; and cycle speed (MHz)
• RISC (reduced instruction set computing)
increases speed; used for scientific, workstation
computing
HUANG Lihua, Fudan University
Feb., - July., 2006
Secondary Storage Technology
• Used for relatively long-term storage of data
outside CPU
• Magnetic disk: floppies, hard disks, RAID
• Optical disk: CD-ROM, CD-RW, DVD
• Magnetic tape
• Storage networking: direct-attached storage;
network-attached storage; storage area networks
HUANG Lihua, Fudan University
Feb., - July., 2006
STORAGE AREA NETWORK (SAN)
• HIGH-SPEED NETWORK
• CONNECTS VARIOUS STORAGE
DEVICES
– TAPE LIBRARIES
– DISK ARRAYS
STORAGE SERVICE PROVIDER: 3rd party
rents storage space
*
HUANG Lihua, Fudan University
Feb., - July., 2006
A Storage Area Network (SAN)
HUANG Lihua, Fudan University
Feb., - July., 2006
Input Devices
•
•
•
•
•
•
•
•
•
Keyboard and mouse
Touch screen
Optical character recognition
Magnetic ink character recognition (MICR)
Pen-based input
Digital scanner
Audio input
Sensors
Radio-frequency identification (RFID)
HUANG Lihua, Fudan University
Feb., - July., 2006
POINTING DEVICES
• KEYBOARD
• MOUSE
–
–
–
–
WIRED
INFRA-RED
TRACKBALL
TOUCH PAD
• JOYSTICK
• TOUCH SCREEN
*
HUANG Lihua, Fudan University
Feb., - July., 2006
© 2002 by Prentice Hall
SOURCE DATA AUTOMATION
• Captures data in computer-readable form at the
time and place the data are created
• OPTICAL CHARACTER RECOGNITION
(OCR): translate designed marks, characters, and
codes into digital form.
– BAR CODE: Identifies products in stores, warehouses,
shipments
• MAGNETIC INK CHARACTER
RECOGNITION (MICR): translate characters
written in magnetic ink into digital format
– Special ink identifies
bank, account, amount
HUANG Lihua, Fudan University
*
Feb., - July., 2006
© 2002 by Prentice Hall
SOURCE DATA AUTOMATION
• PEN-BASED INPUT: Digitizes signature
• DIGITAL SCANNER: Translates images &
characters into digital form
• VOICE INPUT DEVICES: Converts spoken word
into digital form
• SENSORS: Devices that collect data from
environment for computer input (e.g.,
thermometers, pressure gauges)
• *
HUANG Lihua, Fudan University
Feb., - July., 2006
© 2002 by Prentice Hall
OUTPUT DEVICES
•
•
•
•
CATHODE RAY TUBE (CRT)
PRINTER
PLOTTER
VOICE OUTPUT DEVICE
*
HUANG Lihua, Fudan University
Feb., - July., 2006
CATEGORIES OF
COMPUTERS
• Mainframe:
– Largest computer; handles massive amounts of data;
used for large business, scientific, military applications
• Midrange computer:
– Smaller, less expensive minicomputers or servers; used
for smaller organizations or managing networks
• Minicomputers:
– Used in systems for universities, factories, research labs
• Servers:
– Manage internal company networks or Web sites
HUANG Lihua, Fudan University
Feb., - July., 2006
CATEGORIES OF COMPUTERS
• Personal computer:
– Portable or desktop microcomputer
• Workstation:
– More powerful desktop computer used for
computation-intense tasks
• Supercomputer:
– Sophisticated, powerful computer used for tasks
requiring rapid, complex calculations; weapons
research, weather forecasting
HUANG Lihua, Fudan University
Feb., - July., 2006
Computer hardware trends
(1) The CPU
(2) Storage devices
(3) User Interfaces
(4) Type of PCs
• Performance----better
• Price----lower
• Size----more compact
HUANG Lihua, Fudan University
Feb., - July., 2006
Computer Networks and
Client/Server Computing
• Distributed processing:
– Distribution of processing work among
multiple computers
• Centralized processing:
– Accomplished by one large central computer
• Client/server computing:
– Splits processing between “clients” and
“servers” on network
HUANG Lihua, Fudan University
Feb., - July., 2006
Client/server computing
HUANG Lihua, Fudan University
Feb., - July., 2006
Types of client/server computing
HUANG Lihua, Fudan University
Feb., - July., 2006
Network Computers and Peer-toPeer Computing
• Network computer (NC):
– Simplified desktop computer, does not store data
permanently
• Peer-to-peer computing:
– Distributed processing that links computers through
Internet or private networks
• Grid computing:
– Applies computational resources of many networked
computers to solve a large, complex problem
HUANG Lihua, Fudan University
Feb., - July., 2006
Assignment for Session 7
•
Individual Preparation for session 7
–
Reading Materials
•
–
P135. Review Quiz
•
•
Textbook: chapter 4
Write down in your book, not submit
Group Assignment: bring to class
–
–
Please design the software architecture for Mr.
Wang’s Pottery Company, including system
software, application software.
Prepare for the CASE QUESTIONS on P.121.
HUANG Lihua, Fudan University
Feb., - July., 2006