Memory Organization in a Computer System
Chapter 5
Memory Organisation
5.1 Introduction
The memory unit is an essential component in any digital computer since it is needed for storing programs and data. Main Memory The memory unit that communicates directly with the CPU is called the main memory. Auxiliary Memory Devices that provide backup storage are called auxiliary memory. The most common auxiliary memory devices used in computer systems are magnetic disks and tapes.
The part of the computer system that supervises the flow of information between auxiliary and main memory is called the memory management system.
2 FP203 Computer
5.1.1 Main Memory
The main memory is the central storage unit a computer system. It is a relatively large and fast memory used to store programs and data during the computer operation.
What is the Main Memory???
3 FP203 Computer Organisation
5.1.2 Memory Hierarchy in a Computer System
Fast and Expensive
Increasing performance and increasing cost
Slow and Inexpensive
4 FP203 Computer Organisation
The Properties of the Memory Hierarchy
Memory Type
Register Cache Main Memory Disk Memory
Access Time
1 ns 5-20 ns 60-80 ns 10 ms
5
FP203 Computer Organisation
Memory Organization in a computer system
Auxiliary Memory
Magnetic Tapes Magnetic Tapes
I/O Processor
Main Memory
CPU
Cache Memory
6
FP203 Computer Organisation
5.1.3 Various types of semiconductor memory technologies
The principal technology used for the main memory is based on semiconductor integrated circuit such: RAM – Random Access Memory ROM – Read-only Memory
PROM – Programmable ROM
EPROM – Erasable PROM EEPROM – Electrically Erasable PROM Flash Memory – can be electrically rewritten tens of thousands of times (used extensively in digital video cameras and for control program in set-top cable television decoders and other devices.)
7 FP203 Computer Organisation
5.1.4 Various types of external memory
Magnetic Disk is a circular plate
Memory Organisation
5.1 Introduction
The memory unit is an essential component in any digital computer since it is needed for storing programs and data. Main Memory The memory unit that communicates directly with the CPU is called the main memory. Auxiliary Memory Devices that provide backup storage are called auxiliary memory. The most common auxiliary memory devices used in computer systems are magnetic disks and tapes.
The part of the computer system that supervises the flow of information between auxiliary and main memory is called the memory management system.
2 FP203 Computer
5.1.1 Main Memory
The main memory is the central storage unit a computer system. It is a relatively large and fast memory used to store programs and data during the computer operation.
What is the Main Memory???
3 FP203 Computer Organisation
5.1.2 Memory Hierarchy in a Computer System
Fast and Expensive
Increasing performance and increasing cost
Slow and Inexpensive
4 FP203 Computer Organisation
The Properties of the Memory Hierarchy
Memory Type
Register Cache Main Memory Disk Memory
Access Time
1 ns 5-20 ns 60-80 ns 10 ms
5
FP203 Computer Organisation
Memory Organization in a computer system
Auxiliary Memory
Magnetic Tapes Magnetic Tapes
I/O Processor
Main Memory
CPU
Cache Memory
6
FP203 Computer Organisation
5.1.3 Various types of semiconductor memory technologies
The principal technology used for the main memory is based on semiconductor integrated circuit such: RAM – Random Access Memory ROM – Read-only Memory
PROM – Programmable ROM
EPROM – Erasable PROM EEPROM – Electrically Erasable PROM Flash Memory – can be electrically rewritten tens of thousands of times (used extensively in digital video cameras and for control program in set-top cable television decoders and other devices.)
7 FP203 Computer Organisation
5.1.4 Various types of external memory
Magnetic Disk is a circular plate