CRC error detection computes the remainder of a polynomial division of a generator polynomial into a message. The remainder, which is usually 16 or 32 bits, is then appended to the message. When another remainder is computed, a nonzero value indicates an error. Depending on the generator polynomial's size, the process can fail in several ways, however. It is very difficult to determine how effective a given CRC will be at detecting errors.
The probability p that a completely random (bad) message will be incorrectly accepted as valid (not detected as a CRC error), is completely a function of the code rate: p = 2-r = 2-(n - k). Where
Use of the CRC technique for error correction normally requires the ability to send retransmission requests back to the data source.
Oops, you are right. I hope it's fixed now. Thank you.
David A Cary Says:
16-bit CRC routine (isochronous) for the polynomial 0x8005+
Scott Dattalo, Dave Dribin (2002-08-24)
A quick guide to CRC: With example calcuation of CRC 16 by Pierre Desrochers +
|file: /Techref/method/error/crc.htm, 6KB, , updated: 2011/11/28 21:08, local time: 2018/9/20 20:20,
|©2018 These pages are served without commercial sponsorship. (No popup ads, etc...).Bandwidth abuse increases hosting cost forcing sponsorship or shutdown. This server aggressively defends against automated copying for any reason including offline viewing, duplication, etc... Please respect this requirement and DO NOT RIP THIS SITE. Questions?|
<A HREF="http://www.piclist.com/techref/method/error/crc.htm"> Cyclic Redundancy Check error detection</A>
|Did you find what you needed?|
PICList 2018 contributors:
o List host: MIT, Site host massmind.org, Top posters @20180920 RussellMc, Van Horn, David, Sean Breheny, David C Brown, Isaac M. Bavaresco, Bob Blick, Neil, Denny Esterline, Harold Hallikainen, John Gardner,
* Page Editors: James Newton, David Cary, and YOU!
* Roman Black of Black Robotics donates from sales of Linistep stepper controller kits.
* Ashley Roll of Digital Nemesis donates from sales of RCL-1 RS232 to TTL converters.
* Monthly Subscribers: Gregg Rew. on-going support is MOST appreciated!
* Contributors: Richard Seriani, Sr.
Welcome to www.piclist.com!