• Skip to main content
  • Skip to primary sidebar
  • Skip to secondary sidebar
  • Skip to footer

Computer Notes

Library
    • Computer Fundamental
    • Computer Memory
    • DBMS Tutorial
    • Operating System
    • Computer Networking
    • C Programming
    • C++ Programming
    • Java Programming
    • C# Programming
    • SQL Tutorial
    • Management Tutorial
    • Computer Graphics
    • Compiler Design
    • Style Sheet
    • JavaScript Tutorial
    • Html Tutorial
    • Wordpress Tutorial
    • Python Tutorial
    • PHP Tutorial
    • JSP Tutorial
    • AngularJS Tutorial
    • Data Structures
    • E Commerce Tutorial
    • Visual Basic
    • Structs2 Tutorial
    • Digital Electronics
    • Internet Terms
    • Servlet Tutorial
    • Software Engineering
    • Interviews Questions
    • Basic Terms
    • Troubleshooting
Menu

Header Right

Home » Fundamental » Memory » Register – What is Registers? Types of Registers
Next →
← Prev

Register – What is Registers? Types of Registers

By Dinesh Thakur

Register are used to quickly accept, store, and transfer data and instructions that are being used immediately by the CPU, there are various types of Registers those are used for various purpose. Among of the some Mostly used Registers named as AC or Accumulator, Data Register or DR, the AR or Address Register, program counter (PC), Memory Data Register (MDR) ,Index register,Memory Buffer Register.

These Registers are used for performing the various Operations. While we are working on the System then these Registers are used by the CPU for Performing the Operations. When We Gives Some Input to the System then the Input will be Stored into the Registers and When the System will gives us the Results after Processing then the Result will also be from the Registers. So that they are used by the CPU for Processing the Data which is given by the User. Registers Perform:-

1)    Fetch: The Fetch Operation is used for taking the instructions those are given by the user and the Instructions those are stored into the Main Memory will be fetch by using Registers.

2)    Decode: The Decode Operation is used for interpreting the Instructions means the Instructions are decoded means the CPU will find out which Operation is to be performed on the Instructions.

3)    Execute: The Execute Operation is performed by the CPU. And Results those are produced by the CPU are then Stored into the Memory and after that they are displayed on the user Screen.

Types of Registers are as Followings

MAR stand for Memory Address Register

This register holds the memory addresses of data and instructions. This register is used to access data and instructions from memory during the execution phase of an instruction. Suppose CPU wants to store some data in the memory or to read the data from the memory. It places the address of the-required memory location in the MAR.

Program Counter 

The program counter (PC), commonly called the instruction pointer (IP) in Intel x86 microprocessors, and sometimes called the instruction address register, or just part of the instruction sequencer in some computers, is a processor register

It is a 16 bit special function register in the 8085 microprocessor. It keeps track of the the next memory address of the instruction that is to be executed once the execution of the current instruction is completed. In other words, it holds the address of the memory location of the next instruction when the current instruction is executed by the microprocessor.

Accumulator Register

This Register is used for storing the Results those are produced by the System. When the CPU will generate Some Results after the Processing then all the Results will be Stored into the AC Register.

Memory Data Register (MDR)

MDR is the register of a computer’s control unit that contains the data to be stored in the computer storage (e.g. RAM), or the data after a fetch from the computer storage. It acts like a buffer and holds anything that is copied from the memory ready for the processor to use it. MDR hold the information before it goes to the decoder.

MDR which contains the data to be written into or readout of the addressed location. For example, to retrieve the contents of cell 123, we would load the value 123 (in binary, of course) into the MAR and perform a fetch operation. When the operation is done, a copy of the contents of cell 123 would be in the MDR. To store the value 98 into cell 4, we load a 4 into the MAR and a 98 into the MDR and perform a store. When the operation is completed the contents of cell 4 will have been set to 98, by discarding whatever was there previously.

The MDR is a two-way register. When data is fetched from memory and placed into the MDR, it is written to in one direction. When there is a write instruction, the data to be written is placed into the MDR from another CPU register, which then puts the data into memory.

The Memory Data Register is half of a minimal interface between a micro program and computer storage, the other half is a memory address register.

Index Register 

A hardware element which holds a number that can be added to (or, in some cases, subtracted from) the address portion of a computer instruction to form an effective address. Also known as base register. An index register in a computer’s CPU is a processor register used for modifying operand addresses during the run of a program.

Memory Buffer Register

MBR stand for Memory Buffer Register. This register holds the contents of data or instruction read from, or written in memory. It means that this register is used to store data/instruction coming from the memory or going to the memory.

Data Register

A register used in microcomputers to temporarily store data being transmitted to or from a peripheral device.

You’ll also like:

  1. What is a Register Variable
  2. How To Register Your Website Domain Name with godaddy
  3. What is scope & storage allocation of register, static and local variables
  4. Types of Storage Device | Types of Backup
  5. Types of integrity
Next →
← Prev
Like/Subscribe us for latest updates     

About Dinesh Thakur
Dinesh ThakurDinesh Thakur holds an B.C.A, MCDBA, MCSD certifications. Dinesh authors the hugely popular Computer Notes blog. Where he writes how-to guides around Computer fundamental , computer software, Computer programming, and web apps.

Dinesh Thakur is a Freelance Writer who helps different clients from all over the globe. Dinesh has written over 500+ blogs, 30+ eBooks, and 10000+ Posts for all types of clients.


For any type of query or something that you think is missing, please feel free to Contact us.


Primary Sidebar

Computer Memory

Computer Memory

    • Computer - Memory
    • Computer - Types of Memory
    • Computer - RAM
    • Computer - Types of RAM
    • Computer - ROM
    • Computer - RAM Vs ROM
    • Computer - Associative Memory
    • Computer - SemiConductor Memory
    • Computer - Primary Memory
    • Computer - Auxiliary Memory
    • Computer - Flash Memory
    • Computer - EPROM
    • Computer - Secondary Memory
    • Computer - Sequential Access Memory
    • Computer - EEPROM
    • Computer - Bubble Memory
    • Computer - DDRAM Vs FPMDRAM
    • Computer - SDRAM
    • Computer - DRAM
    • Computer - VRAM
    • Computer - ECC Memory
    • Computer - PC RAM
    • Computer - NVRAM
    • Computer - Register

Computer Devices

    • Computer - Input/Output Devices
    • Computer - Printer
    • Computer - Laser Printer
    • Computer - Hard Drive
    • Computer - Dot-Matrix Printer
    • Computer - Impact and Non-Impact
    • Computer - Storage Devices
    • Computer - Primary Storage
    • Computer - Types of Storage
    • Computer - Line Printer

Other Terms

    • Computer - Interrupt
    • Computer - Classify Storage Devices
    • Computer - CISC and RISC
    • Computer - Access Method
    • Computer - Memory Mapping
    • Computer - OMR
    • Computer - Access Time
    • Computer - Types of integrity
    • Computer - Buffer
    • Computer - Associative Cache
    • Computer - RAM Parity
    • Computer - Disk Cache
    • Computer - Disk Controller
    • Computer - Cycle Time
    • Computer - IDE
    • Computer - RAM Disk
    • Computer - Cartridge Hard Disk
    • Computer - DPI
    • Computer - Fatal Error
    • Computer - Install HDD/SSD
    • Computer - Input Technologies
    • Computer - OCR

Binary Number

  • CO - EBCDIC
  • CO - ASCII Code
  • CO - Bit
  • CO - ASCII
  • CO - BCD Numbers
  • CO - Binary Numbers
  • CO - Byte
  • CO - Bits and Bytes
  • CO - Machine Code

Other Links

  • Computer Memory - PDF Version

Footer

Basic Course

  • Computer Fundamental
  • Computer Networking
  • Operating System
  • Database System
  • Computer Graphics
  • Management System
  • Software Engineering
  • Digital Electronics
  • Electronic Commerce
  • Compiler Design
  • Troubleshooting

Programming

  • Java Programming
  • Structured Query (SQL)
  • C Programming
  • C++ Programming
  • Visual Basic
  • Data Structures
  • Struts 2
  • Java Servlet
  • C# Programming
  • Basic Terms
  • Interviews

World Wide Web

  • Internet
  • Java Script
  • HTML Language
  • Cascading Style Sheet
  • Java Server Pages
  • Wordpress
  • PHP
  • Python Tutorial
  • AngularJS
  • Troubleshooting

 About Us |  Contact Us |  FAQ

Dinesh Thakur is a Technology Columinist and founder of Computer Notes.

Copyright © 2025. All Rights Reserved.

APPLY FOR ONLINE JOB IN BIGGEST CRYPTO COMPANIES
APPLY NOW