CRC16-CCITT

CRC16-CCITT checksum algorithm.

This implementation of CRC16 is based on the CCITT specification using 0x1D0F as a start value. Using a different start value is possible by calling crc16_ccitt.h::crc16_ccitt_update() with the desired start value instead of crc16_ccitt.h::crc16_ccitt_calc().

There is a more generalized version in CRC16 (lightweight), that does not utilize a look-up table as this implementation does (and is thus also for more memory efficient). Its caveat however is that it is slower by about factor 8 than this version.

uint16_t crc16_ccitt_update(uint16_t crc, const unsigned char * buf, msp430_types.h::size_t len)

Update CRC16-CCITT.

Parameters

crc:A start value for the CRC calculation, usually the return value of a previous call to crc16_ccitt.h::crc16_ccitt_calc() or crc16_ccitt.h::crc16_ccitt_update()
buf:Start of the memory area to checksum
len:Number of bytes to checksum

Return values

  • Checksum of the specified memory area based on the given start value
uint16_t crc16_ccitt_calc(const unsigned char * buf, msp430_types.h::size_t len)

Calculate CRC16-CCITT.

Parameters

buf:Start of the memory area to checksum
len:Number of bytes to checksum

Return values

  • Checksum of the specified memory area