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Computer-System Structure 1

2

Computer-System

Structure

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Structure

Computer-System Structure 2

Computer System Operation (

) I/O Structure ( I/O) Storage Structure () Storage Hierarchy ( ) Hardware Protection () General System Architecture ()

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Computer-System Structure 3

Computer-SystemArchitecture

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Computer-System Structure 4

Computer-System Operation -

local buffers local buffers

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Computer-System Structure 5

Common Functions ofInterrupts Interrupt -

Disable

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Computer-System Structure 6

Interrupt

program counter

Polling - vectoredinterrupt system -

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Computer-System Structure 7

I/O Structure - wait

-1

-

System call

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Computer-System Structure 8

Two I/O MethodsSynchronous Asynchronous

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Computer-System Structure 9

Device-Status Table

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Computer-System Structure 10

rect emory ccessStructure -

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Computer-System Structure 11

Storage Structure

Main memory

Secondary storage

Magnetic disks

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Computer-System Structure 12

ov ng- ea sMechanism

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Computer-System Structure 13

Storage Hierarchy

Speed () Cost () Volatility ()

Caching

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Computer-System Structure 14

Storage-Device Hierarchy

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Computer-System Structure 15

Migration of A From Disk toRegister

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Computer-System Structure 16

Hardware Protection Dual-Mode Operation () I/O Protection (-) Memory Protection ( ) CPU Protection ()

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Computer-System Structure 17

Dual-Mode Operation

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Computer-System Structure 18

Dual-Mode Operation ()Mode bit 1

0 1

monitor user

Interrupt/fault

set user mode

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Computer-System Structure 19

I/O Protection -

monitor mode

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Computer-System Structure 20

Use of A System Call to PerformI/O

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Computer-System Structure 21

Memory Protection

interrupt vector interrupt service routine

2

Limit register

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Computer-System Structure 22

Register

d dd

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Computer-System Structure 23

Hardware AddressProtection

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Computer-System Structure 24

Network Structure Local Area Networks (LAN) Wide Area Networks (WAN)