CRC 16 CCITT

Calculation of CRC 16 CCITT polynomial. More...

Collaboration diagram for CRC 16 CCITT:

Files
file	crc16-ccitt.h
	Calculation of CRC 16 CCITT polynomial.

Functions
void	crc16_ccitt_single (uint16_t *crc, const uint8_t chr)
	Update crc16_ccitt variable with one data byte.
uint16_t	crc16_ccitt (const uint8_t block[], size_t blockLength, uint16_t crc)
	Calculate CRC sum on block of data.

Detailed Description

Calculation of CRC 16 CCITT polynomial.

Equation:

x^16 + x^12 + x^5 + 1

Function Documentation

crc16_ccitt_single()

void crc16_ccitt_single	(	uint16_t *	crc,
		const uint8_t	chr )

Update crc16_ccitt variable with one data byte.

This function updates crc variable for one data byte using crc16 ccitt algorithm.

Parameters

[in,out]	crc	Externally defined variable for CRC checksum. Before start of new CRC calculation, variable must be initialized (zero for xmodem).
	chr	One byte of data

crc16_ccitt()

uint16_t crc16_ccitt	(	const uint8_t	block[],
		size_t	blockLength,
		uint16_t	crc )

Calculate CRC sum on block of data.

Parameters

block	Pointer to block of data.
blockLength	Length of data in bytes;
crc	Initial value (zero for xmodem). If block is split into multiple segments, previous CRC is used as initial.

Returns

Calculated CRC.