Microprocessor with built-in portion for the cyclic redundancy check and methods for performing operations for the cyclic redundancy check using this

Arithmetic unit (ALU) for a microprocessor having a shift circuit (SFT), which selectively performs a CRC operation or a shift operation, with a plurality of input lines to the parallel Apply of input data in the data bits (0-7) of the shift circuit (SFT) are taken, and in the case of CRC operation to pick up a Anfangsbinarwerts as a base value for a CRC calculation, a one-bit line (RR) serially receives one bit of data for which the CRC operation is carried out, (EXOR) which has a function generating means comprises one or a plurality of exclusive-OR gate and the data bits (0-7) of the shift circuit and the data (RR) receives the one-bit line, a selector (SL), which in the case of CRC operation, the output data of the function generating means (EXOR) and in the case of shift operation, the data bits (0-7) selected by the shift circuit, the shift circuit shifting the selected data bits than data bits (0-7 ) of the shift circuit and the bit (RR) is performed by the one-bit line, and a plurality of output lines for outputting in parallel the data bits ...