CLASSIFICATION OF MEMORY HIERARCHY IN THE SYSTEM UNIT

BY DEEPJYOTI TALUKDAR.B.TECH(COMPUTER SCIENCE & ENG.)

4TH SEM.UNDER THE GUIDANCE SIR SWAPON MANDOL,

Introduction“The memory unit is the most essential part in any digital system as it need to store programs and data.There is just not enough space in one memory unit to accomodate all the programs used in a typical computer.However,most users accumulate and continue to accumulate a large amount of data processing software or programs.Not all the information is required by the CPU at same time.For the classification of memory hierarchy various devieces are introduce for computers as for backup storage and for the performance.”

● What is Memory?→A computer memory is that

which have the capacity to store a bulk of programs permanently and temporarily within the system.

Contd.

What is the basic difference between a human memory and computer memory?

→Human memory and computer memory are both very complex storage device.There are three parts in human memory:sensory

memory,short term/working memory, and long term memory.These three types related to computer

processing.When a computer first encodes information this is relevant to sensory

memory which has the ability to preserve sensory information for a very brief period. After you have processed the information its is sent to short term memory.This could be related to RAM.The

last type of Human memory is long term memory.This can be related to the

Hard Drive of a system unit of a computer.

HUMAN MEMORY VS COMPUTER MEMORY

Contd.

→Although computer memory is much faster at processing software,the human brain in fact larger in storage capacity.A computer has many types of storage mediums such as removable disks drives,tape drives,cache memory and hard drives.Unlike computer memory,the human brain cannot be inputted with other forms of memory and this is the largest difference between the two.

Priority Order of Memory Hierarchy in The Sytem Unit.

Fig. Showing its Types of Memory, Performance, and its Capacity.

Fig.Types of Memory Hierarchy and its size with respect to its cost.

Description of each memory hierarchy:-●Register sets- there are 4 types of memory register present in the cpu,,,which Stores addresses of curently executable data.Its types PC-program Counter,Mar-Memory Address Register,IR-Instruction register & MR-Memory Register.

●Cache Memory-It is a very high Speed Memory, very expense in cost depend in it’s size.Performs work faster and takes minimum time.

contd

05/01/2023

Main Memory-Mainly Ram and Rom.Ram stands for Random Access Memory .It has the ability to read and write and it is volatile.It doesn’t stores data permanently.It holds only current data that is recommended by the cpu.Its information Lost as long as power applied to the unit.

Fig:-RAM(Random Access Memory)

*●Rom-Its accronym is Read Only Memory.It has the tendency to only Read.Although Rom is also Random access.RAM is used for storing the bulk of programs and data that are subject to change.ROM is used for storing programs that are permanently resident in the computer and for table of constants that do not change in value once the production of the computer is completed.

* ●Hard Disk-It is known as the Virtual Memory,Which is the permanent memory within the system.Where the user accumulate a huge load of programs and data for such a longer period of time.So, such the Ram(main memory) takes the required information which is currently needed by the processor.There are two types of Hard drives- Internal and External Hard Drives.

Fig.External HD.Fig.Internal HD.

●Magnetic Disk-A magnetic Disk is a circular plate constructed of metalOr plastic coated with magnetized material.(eg. Compact Disks,DvDs).This Types of memory is cheap in cost and need for backup storage,which is alsoCalled auxilary memory.CD’s available in MB’s and Dvd’s in GB’s.

Fig: eg of Magnetic Disk(CD)●Magnetic Tapes-A magnetic tape is a strip of plastic coated with magneticRecording medium.For eg.Floppy disks…etc two common size is used is 3.5 Inches and 5.25 inches.Having memory of 1.44 mbs etc….

Fig:Magnetic Tapes(Floppys).

BIBLIOGRAPHY.

1. Computer System and Architecture- M.Morris Mano.

2.GOOGLE.

3.Wikipedia

4.Computer Architecture –William Stallings.

CONCLUSIONThe Important point of the Memory Hierarchyis to know its access mode,access time,trasfer rate,capacity and its cost.

THANKING YOU.