Cyclic Redundancy Check 16 (CRC16) calculation
[Libraries]

The Cyclic Redundancy Check 16 is a hash function that produces a checksum that is used to detect errors in transmissions. More...

Files
file	crc16.c
	Implementation of the CRC16 calculcation.
file	crc16.h
	Header file for the CRC16 calculcation.
Functions
unsigned short	crc16_add (unsigned char b, unsigned short crc)
	Update an accumulated CRC16 checksum with one byte.
unsigned short	crc16_data (const unsigned char *data, int datalen, unsigned short acc)
	Calculate the CRC16 over a data area.

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Detailed Description

The Cyclic Redundancy Check 16 is a hash function that produces a checksum that is used to detect errors in transmissions.

The CRC16 calculation module is an iterative CRC calculator that can be used to cumulatively update a CRC checksum for every incoming byte.

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Function Documentation

unsigned short crc16_add	(	unsigned char	b,
		unsigned short	crc
	)

Update an accumulated CRC16 checksum with one byte.

Parameters:

	b	The byte to be added to the checksum
	crc	The accumulated CRC that is to be updated.

Returns:

The updated CRC checksum.

This function updates an accumulated CRC16 checksum with one byte. It can be used as a running checksum, or to checksum an entire data block.

Note:

The algorithm used in this implementation is tailored for a running checksum and does not perform as well as a table-driven algorithm when checksumming an entire data block.

unsigned short crc16_data	(	const unsigned char *	data,
		int	datalen,
		unsigned short	acc
	)

Calculate the CRC16 over a data area.

Parameters:

	data	Pointer to the data
	datalen	The length of the data
	crc	The accumulated CRC that is to be updated (or zero).

Returns:

The CRC16 checksum.

This function calculates the CRC16 checksum of a data area.

Note:

The algorithm used in this implementation is tailored for a running checksum and does not perform as well as a table-driven algorithm when checksumming an entire data block.