Based on NIELIT, BY Impulse Technology
The word computer comes from the word compute which means to calculate so a computer is normally considered as a computing device that can perform arithmetical operation at an a high speed. Computer had a great impact in our everyday life.
Analog Computer Analog computer process information of physical nature, that uses the continuously changeable aspects of physical phenomena such as electrical, mechanical, or hydraulic quantities to model the problem being solved. Ex:- Temperature , Pressure , etc.
Digital computer process information in the form of 0 and 1(bit) is known as binary number. In Computing term we mostly refer to digital type of computer. Digital computer fall in different ranges called Micro Computer , Mini Computer, Mainframe Computer, Super Computer Which can be further classified into ascending order of the their size – Small, Medium, Large, Very large.
Hybrid computers is a combination of digital computer and analog, both. The digital component normally serves as the controller and provides logical and numerical operations, while the analog component often serves as a solver of differential equations and other arithmetical complex equations. .
The internal arrangement of digital computer parts(Input Unit,Output Unit,Central Processing Unit, Memory Unit) is knows as Computer organization. This arrangement can be different from one computer to another computer system Digital computer performed following operation -Inputting, outputting, processing, storing, controlling all above operation is done by the CPU in Digital computer..
It is the brain of computers system. In computer system all major operation (calculation, manipulation, comparison) are made by CPU. The CPU is responsible for activating & controlling the operation performed by all other unit of computer system. The Micro processor is the CPU of computer system .It is the unit of computer that interprets the instruction and executes them..
All Calculation and comparison are made by the ALU. Arithmetic Unit design to performed Arithmetic Operation Add, Subtract, Multiply, Divide, and logical unit performed logical unit performed logical operation or comparison such as <,>, =..
How does the input device know that it is time to fit data into storage unit How does the All know what should be done with the data ones it is retrieve all these types of manupulation is done by Control unit (CU) CU obtain instruction From the program store in the memory ,interpreted instruction issue electrical signal that cause other unit of the system to be performed their function ..
The function of the memory or primary memory is to store data an information that is currently running in computer. It is essential component of the computer system..
There are two types of Main memory..
This type of memory contains data and instruction Only for the time that the computer is switch on, as soon as it switch off the main memory losses it contain . example RAM, CACHE.
RAM is a read/writes memory(volatile memory), Data and instruction can be read and write from Ram .RAM is the hardware, that is generally located on the motherboard, and is use to execute the operating system (OS), application programs and data in current use and are kept into RAM so they can be quickly reached by the device's processor..
SRAM can written store information as long as the power supply is on. SRAM is costly and consume more power to store data.They do not need refreshing circuit and higher speed than Dynamic RAM..
DRAM stores each bit of data on a separate capacitor for very sort time, even when power supply is on therefore, DRAM have to be refresh periodically, generally 2 millisecond and have higher packing density with moderate speed and consume less power & used where a large capacity is memory .`
Cache memory is placed between the CPU & the main memory, it is faster than the main memory (RAM). Hence Access time is much less than that of memory .The access time of cache memory is 15-25 nanosecond where as that of main memory 80 nanosecond the cache memory store instruction and data which are to be immediately executed .It is to reduce average access time. The information frequently required by the processer is available in the cache memory .
The Size of the L1 cache very small as comparison to others(L2 or L3) that is between 2KB to 64KB, It is built into actual computer processor core. It is a embedded register in the computer microprocessor(CPU).The Instructions that are required by the CPU that are firstly searched in L1 Cache. Example of registers are accumulator, address register,, Program counter etc.
The Size of the L2 cache is more capacious than L1 cache.It is placed between the CPU and RAM.`
The Size of the L3 cache is more capacious than L1 and L2, it's size is between 1MB to 8MB, and is used in special computer like servers etc.
This(NVM) is a type of computer memory that has the capability to hold saved data even if the power is turned off.