• 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 » Binary » What are BCD numbers
Next →
← Prev

What are BCD numbers

By Dinesh Thakur

Meaning of BCD – “Binary Coded Decimal”, is a method that use binary digits 0 which represent “off” and 1 which represent “on”. BCD has been in use since the first UNIVAC computer. Each digit is called a bit. Four bits are called a nibble and is used to represent each decimal digit (0 through 9).

The first binary number system was documented by Gottfried Leibniz in the 17th century. In 1854 mathematician George Boole came up with a system of logic that is know today as Boolean Algebra (based on two elements 0’s and 1’s).

The binary numbering system use a base of 2 whereas the decimal numbering system use a base of 10. When the binary number is 0, then the number is off, when the binary number is 1, then the number is on. The configuration of BCD is “8421” a 4 bit binary called a nibble . Therefore, the decimal 5 is a BCD 0101: where 0=8, 1=4, 0=2, 1=1; the 8 and 2 are turned off.
The following is an example of binary digits and how they represent decimal digits:

Decimal
BCD
00000
10001
20010
30011
40100
50101
60110
70111
81000
91001

The advantage that Binary Coded Decimal (BCD) has over Binary is that there is no limit to number size. For every decimal number added, you add 4-bits or one nibble. Binary numbers are limited to the largest number that can be represented by 8, 16, 32 and 64 bits. It is easier to convert decimal numbers to and from BCD than Binary.

BCD is usually converted to Binary for arithmetic processing since computers only process 0’s and 1’s. However, hardware can be built to operate directly with BCD. BCD is common in electronic systems where numeric value is displayed. This is done in systems that consist of digital logic and do not contain a microprocessor.

Computer processing requires a minimum of 1 byte (8 bits) therefore, the left portion of each BCD number is wasted storage. Because storage is valuable, storage can be saved by using packed BCD numbers. With packed BCD numbers (e.g. 2 bytes are use to store 3484 instead of 4 bytes) the left byte will consist of 00110100 (34) the right byte will consist of 10000100 (84).

You’ll also like:

  1. BINARY CODED DECIMAL (BCD)
  2. What is Binary Numbers?
  3. Print n Even Numbers in Java Example
  4. Print all the Prime Numbers up to 100
  5. Sum of First N Natural Numbers in Java Example
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 © 2023. All Rights Reserved.