After looking this up, this does not seem to be correct. I'll quote from Noway2 here http://www.eng-tips.com/viewthread.cfm?qid=263494 http://www.eng-tips.com/v

After looking this up, this does not seem to be correct. I'll quote from Noway2 here http://www.eng-tips.com/viewthread.cfm?qid=263494 http://www.eng-tips.com/viewthread.cfm?qid=263494. "There are problems in trying to compute an error rate for which the CRC will fail to detect a bad communication. First, whether or not the error gets through will be highly dependent on the message. Second, CRC was designedto catch short bursts of contiguous bit errors. If the number of error bits is greater than this, there is a chance that CRC will fail. Here is an example: Consider these two hex strings: 1) 4B04B6F9BF002F002C002E002CD12E 2) 00260010BF002F002C002E002CD12E This is from an actual application and uses a 16 bit CRC algorithm to calculate a check value. In both cases the check value is 0x2ED1 (byte swapped). The CRC is the standard CRC used in Modbus, CCITT believe. Mathematically speaking, an X bit CRC will detect all consecutive bit errors less than X bits. When the error burst is bigger than X, the an X bit CRC will detect at a rate of 1-2^-X . For example,a 16 bit CRC has a 99.99847412109375% chance of catching the error burst. As you can see from my example above with the two strings, in reality, error bursts longer than X bits DO HAPPEN AND DO GET THROUGH!"