CRC Function

Generates a Cyclic Redundancy Character (CRC).

Syntax

CRC(char-string{,type})

Syntax Elements

char-string is the data being sent or received expressed as a variable or symbol to which the data string has been assigned, or can be a literal string enclosed in quotes.

type specifies the type of polynomial used to generate the CRC.

1 = CRC-CCITT (X.25 Standard)

0 = CRC16

The default value is 0.

Operation

The CRC function generates a Cyclic Redundancy Character by performing a polynomial function against all the data bytes in the data string.

If type is 0 (or not specified), a sixteen bit CRC is generated using the CRC16 polynomial:

X16 + X15 + X2 + 1

If type is 1, a sixteen bit CRC is generated using the CRC-CCITT (X.25 Standard) polynomial (also known as the ADCCP polynomial):

X16 + X12 + X5 + 1