VMS Help MACRO, VAX MACRO Assembler, Instructions, CRC  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    Purpose:        Calculate cyclic redundancy check for software
                    or communications checking
    Format:         opcode tbl.ab,inicrc.rl,strlen.rw,stream.ab
    Operation:      R0 = CRC_accumulation (initial value - inicrc,
                    polynomial table - tbl, data stream - (stream,
                    strlen))
    C. Codes:       N = {R0 LSS 0}, Z = {R0 EQL 0}, V = 0, C = C
    Exceptions:     None
    Opcodes:        0B    CRC      Cyclic redundancy check
    Description:    The CRC of the data stream pointed to by stream
                    and of length strlen is calculated. The initial
                    CRC is given by inicrc and is normally 0 or -1
                    unless the CRC is calculated in several steps.
                    R0 is replaced by the result. If the polynomial
                    is less than order -32, the result must be
                    extracted from R0. The CRC polynomial is expressed
                    by the contents of the 16-longword table.