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From: ake@dayton.saic.com (Earle Ake)
Newsgroups: comp.sources.wanted,comp.lang.c
Subject: Re: CRC-16 source code wanted
Message-ID: <1991Apr24.094046.1582@dayton.saic.com>
Date: 24 Apr 91 13:40:46 GMT
References: <461@frcs.UUCP>
Distribution: comp
Organization: Science Applications Intl. Corp., Dayton, Ohio
Lines: 33

In article <461@frcs.UUCP>, paul@frcs.UUCP (Paul Nash) writes:
> 
> I am looking for C source code to implement the CRC-16 algorithm.  I
> have seen various from time to time, but cannot think of a place.  If
> you have a suitable (short) routine, please post it or mail me a copy,
> or tell me where I can find one.

int calcrc(prt, count)
char *ptr;
int count;
{
	int crc, i;

	crc = 0;
	while (--count >= 0) {
		crc = crc ^ (int)*ptr++ << 8;
		for (i = 0; i < 8; ++i)
			if (crc & 0x8000)
				crc = crc << 1 ^ 0x1021;
			else
				crc = crc << 1;
		}
	return (crc & 0xFFFF);
}


Earle
_____________________________________________________________________________
             ____ ____    ___
Earle Ake   /___ /___/ / /     Science Applications International Corporation
           ____//   / / /__                 Dayton, Ohio
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