mcf51jf128 Freescale Semiconductor, Inc, mcf51jf128 Datasheet - Page 621

• Manufacturer Part Number: mcf51jf128
• Description: Mcf51jf128 Reference Manual
• Manufacturer: Freescale Semiconductor, Inc

Chapter 28
Cyclic Redundancy Check (CRC)
28.1 Introduction
The cyclic redundancy check (CRC) module generates 16/32-bit CRC code for error
detection.
The CRC module provides a programmable polynomial, SEED, and other parameters
required to implement a 16-bit or 32-bit CRC standard.
The 16/32-bit code is calculated for 32 bits of data at a time.
28.1.1 Features
Features of the CRC module include:
28.1.2 Block diagram
This is a block diagram of the CRC.
Freescale Semiconductor, Inc.
• Hardware CRC generator circuit using a 16-bit or 32-bit (programmable) shift
• Programmable initial seed value and polynomial.
• Option to transpose input data or output data (the CRC result) bitwise or bytewise.
• Option for inversion of final CRC result.
• 32-bit CPU register programming interface.
register.
This option is required for certain CRC standards. A bytewise transpose operation is
not possible when accessing the CRC data register via 8-bit accesses. In this case, the
user's software must perform the bytewise transpose function.
MCF51JF128 Reference Manual, Rev. 2, 03/2011
Preliminary
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