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State and explain the three functional elements/parts of the central processing unit.

State and explain the three functional elements/parts of the central processing unit.

Answers

Isaac
CONTROL UNIT.
Control unit coordinates all processing activities in the cpu as well input,storage
and output operations.
It determines which operations or instructions is to be executed next
to coordinates these activities,the control unit uses a system clock which sends
electric signal as it means of communication.

ARITHMETIC AND LOGIC UNIT.
The arithmetic and logic unit is a unit of central processing unit where all
Arithmetic and logic operation includes addition subtraction,multiplication and division.
Logic operations are based on the computer capacity to compare two or more
Values i.e greater than or less than ,equal to or not equal to etc.
In order for the arithmetic logic unit to be able to process data,its special
Temporary storage locations called registers.

MAIN MEMORY.
Also known as the primary storage is a type of storage that is directly accessible
By the processor .
Computer memory can be classified into ;
a)Read only memory(ROM).
b)Random accessed memory(RAM).

READ ONLY MEMORY.
Is used to store programmed instructions and data permanently or semi-
Permanently.data and instruction stored in Rom remains unchanged for long
Periods of time eg post instructions ,special purpose computer ,computerized
Fuel pumps instructions.
Depending on permanence of of instructions or data written on it ,there are four
Types of read only memory namely;
a)mask read only memory.
Once the content is written on it cannot be changed.
b)programmed read only memory.
Allows the user to alter it only once after the content is written on it .
c)erasable programmamble read only memory.
Has a transparent quartz window through which its contents can be erased by exposing it to ultra violent light and then reprogrammed for another use .


d)Electrically erasable programmed read only memory.
This types can be erased and reprogrammed using electricity.example of this type of memory is the basic input /output system.

Characteristics of read only memory.
One can only read its content but can not write on it unless it’s a special
Types of Rom
It’s non –volatile i.e its content is not lost when the computer is switched off.
Stores permanent or semi-permanent instructions from manufacture
Called firmware.
Can store semi-permanent instructions because some variations of Rom chips can be programmed according to the user specifications.

RANDOM ACCESS MEMORY.
Also know as working storage is used to hold instructions and data needed by
Currently running applications .
Its referred to as random accessed because it content can be read directly regardless
The sequence in which it was stored.

Characteristics of RAM.
Data can be read (retrieved) and written(stored) in it.
RAM is a temporary (volatile)storage because its content disappears when the computer is switched off.
Its content is user defined i.e the user dictates what is to be contained in the RAM.
THE TWO MAIN TYPES OF RAM ARE ;
a)STATIC READ ACCESS MEMORY;is the fast type of memory mostly located inside a microprocessor.is used in special purpose memories such as cache memory.cache memory is used to enhance the processing speed by holding data and instructions that are instantly required by the processor.
b)DYNAMIC RANDOM ACCESS MEMORY;is relatively slower type of RAM compared to SRAM. The term dynamic refers to the tendency for stored change to leak away ,even with constant power supply.for this reason,DRAM requires periodic recharging(refresh) to maintain it data storage.
isaacmuthini answered the question on December 12, 2017 at 12:38

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