technology
Post on 31-Dec-2015
30 Views
Preview:
DESCRIPTION
TRANSCRIPT
Chapter 2
Technology
Computer categories
Mainframes
Minicomputers
Microcomputers
• Traditional categories:small , mid-range and large mainframes andsuper computers
• Application categories:host-computers, database servers, transaction systems and central systems
• Traditional categories:minicomputers, mid-rang systems
• Application categories :departmental systems, network servers, technical workstations , workgroup systems
• Traditional categories :portable , desktop and minitower-computers
• Application categories :personal computers, multi-user systems, netwerk-serverstechnical , office and professional workstations
O’Brien 48
Trends in Computer Characteristics
Size Room Closet Desk Dessktop Credit card?
Generation Fist Second Third Fourth Fifth
Reliability Hours Days weeks Months Years?
Instuct/sec Hundreds Thousands Milions Tens of millions Billions?
Circuitry Vacuum Tubes Transistors IC’s LSI’s VLSI
Memory Thousands 10s Thousands 100s Thousands Millions Billions?
Price/M instr $ 10 $ 1.0 $ 0.1 $ 00.01 $ 0.0001?
O’Brien p 50
Categories
Microcomputers or personal computers
Midrange computers or minicomputers
Mainframe computers
Supercomputers
Computer Networks
client/server systems
network computers
O’Brien 51-54
Client/Server
Host systemsuper server
ClientServer
• types• Functionality
O’Brien p 55
Multimedia Computersystemen
O’Brien p 56
Multimedia
Technologies : Languages HTML, JAVA Hypertex Hypermedia
Elements CDI compact disk interactive Compressed audio Computer edit systems Digital audio DVI digital video interactive MIDI musical instrument digital interface Sound card Video capture card
O’Brien p 57-58
Design of a computer systemCentral processing unit
CPU
Input deviceinputs data and
instructionsinto the CPU
• Keyboard• mouse• touch screen• optical scanner• light pen• speech input• barcode• ....
Control UnitTranslates instructions and manages processing
Arithmetic/Logicalunit (ALU)
Executes arithmeticoperations and compares
Internal storage unitStores data and instructions
during execution
Output device
• video screen• printer• loudspeaker• video• ...
External storageStores data andprograms for
the applications
O’Brien 60
Peripheral Devices
terminals video, hand terminals, intelligent terminals,
transaction-terminals (POS), ... Pointing devices
pictogram, mouse, trackball, joystick, touch-sensitive, light pen, graphical tablet
Terminal input/output LCD, plasma, video-output, impact printers, laser printer,
inktjet printer Speech input/output Optical and magnetic recognition (OCR , MICR) Storage: tape, magnetic disk , optical disk (ROM , WORM)
O’Brien 63 - 79
The “Von Neumann” Computer
INTERFACE
INTERFACE
Data memory
Arithmetic unit
Control unit
Program memory
Programmer Interface
DATA
RESULTS
Computer Architecture
Input and Output Converters translate the external representation into an
internal representation or the other way around.
eg: keyboards, video screens , printers, barcode readers, magnetic cards, sensors, ...
Data memory Temporary storage of data
. intermediate results ( eg. program variables )
. input/output buffers
Computer Architecture 2
Program memoryContains the instructions that go via the program interface to
the CPU and that will be executed one by one.
Central memory
A set of numbered cells that can contain a binary number.
Terminology: . word
. address
Program variables represent an address
Central Memory
25 200 314 24 573
73 55 478 900
00 01 02 03 04 05 06
10 11 12 13 14 15
20 21 22 23 24 25
addresscontents
In most computers , data memory and program memory are only logically separated
Storage
Semiconductormemory
Magnetic disks
Magnetic tape
Optical disk
Acces
s spee
d incr
ease
s
Stora
ge ca
pacity
dec
reas
es
Cost/b
yte i
ncrea
ses
RAMROM
Primary
Secondary
Tekst: O’Brien p 74
Computer Architecture 3
Arithmetic and Logical Unit
This unit is responsible for the processing of the data read from, and rewritten into the data memory.
The unit can compare the contents of memory cells and execute basic operations.
The Control Unit
This unit reads the instructions one by one from the program memory , decodes them and sends the appropriate signals to the other components.
Peripheral Memory
. Uses no electrical energy
. Usually stored in blocks of hundreds of words , which are moved as one block into the central memory
. Magnetic material in permanent movement
- disk memory < 1/10 sec : allows " random access "
- Magnetic tapes : sequential memory
. Optical material
- CD-ROM : to distribute large amounts of data
- WORM : archiving
Usage of Memory
Registers
central memory
Mass storage( disk - tape )
Priceper bit
AccessTime
Registers: Very fast memory ( < 100 ns ) in arithmetic and control unit
Central memory: ( between 50 and 500 ns )
These types of memory use integrated circuits and use electrical energy. The content is lost with a power supply interruption.
Units
Memory capacity
Kilobyte: one thousand bytes Megabyte: one million bytes Gigabyte: one billion bytes Terabyte: one trillion bytes
Time
Millisecond: one thousandth of a second Microsecond: one millionth of a second Nanosecond: one billionth of a second Picosecond: one trillionth of a second
O’Brien 61
Memory Access Time
price
access time
100
10
1
10 10 10 10 1s
-8 -6 -4 -2
I.C.
Disk
CD-ROM
Tape
Coding Data
Numerical Data
- integer : binary numbers
1. 2 + 0. 2 + 1. 2 + 0. 2 + 1. 2 =
10101 b = 21 d
- real numbers
mantissa and exponential part
4 3 2 1 0
ASCII computer codes
0 048 30 060 00110000 1 049 31 061 00110001 2 050 32 062 00110010 3 051 33 063 00110011 4 052 34 064 00110100 5 053 35 065 00110101 6 054 36 066 00110110 7 055 37 067 00110111 8 056 38 070 00111000 9 057 39 071 00111001 : 058 3A 072 00111010 ; 059 3B 073 00111011 .....
A 065 41 101 01000001 B 066 42 102 01000010 C 067 43 103 01000011 D 068 44 104 01000100 E 069 45 105 01000101 F 070 46 106 01000110 G 071 47 107 01000111 H 072 48 110 01001000 I 073 49 111 01001001 J 074 4A 112 01001010 K 075 4B 113 01001011 L 076 4C 114 01001100 .....
char dec hex oct binary char dec hex oct binary
O’Brien 61
Complex Configuration
LAN/WAN Remote
DataBase
Hardware Schema Microcomputer
System bus
...
othersystem management
and equipment
CentralMicroprocessor
SupportingMicroprocessor
RAM ROM
Keyboard Interface
DisplayInterface
CD-ROMInterface
SerialInterface
DiskdriveInterface
ParallelInterface
Keyboard Video screen CD-ROM Modem Diskette station Printer
...
Internal memory
Instructions
Information processing instructions
opc. op.1 op.2 res next
opc. op.1 op.2 next1next2
Control instructions
opc. = operation code
op.1 = address in memory of the first operand
op.2 = address in memory of the second operand
next = address in the program memory of the next instruction
next1 = address of the next instruction if a condition is true
next2 = address of the next instruction if a condition is false
Program Example
Data memory
Arithmetic unit
Control unit
Program memory
Programmer Interface
1 2 3
4 5 6
7 8 9
* 0 #
1 2 3
4 5 6
7 8 9
* 0 #
Computer controlled door
Computer Controlled Door
1
2
3
4
5
6
7
8
9
STO
STO
EQ?
MUL
ADD
ADD
NE?
NE?
STO
0
0
KFL
D2
D2
D1
D1
D2
1
-
-
0
10
KDA
1
3
207
-
D1 P2
D2 P3
P3 P4
D2 P5
D2 P6
D1 P7
P3 P8
P1 P9
DDA P1
KFL key flag
KDA key data
DDA door data
D1 number of digits read
D2 value read
Usage of P-register
P - register or ordinal counter
Control Unit
+1
P-register
I-register
Program Memory
opc.
op.1
op.2
res
opc.
op.1
op.2
next
Control instructions
Information processing instructions
Door program with P-register
1
2
3
4
5
6
7
8
9
10
STO
STO
EQ?
MUL
ADD
ADD
NE?
NE?
STO
JMP
0
0
KFL
D2
D2
D1
D1
D2
1
-
-
-
0
10
KDA
1
3
207
-
-
D1
D2
P3
D2
D2
D1
P3
P1
DDA
P1
Client server
Clients
Clients
comm.server
comm.server
DB.server
DB.server
DB.server
O.A.server
top related