Cyclic Redundancy Checker (CRC) UnitMPC5644A Microcontroller Reference Manual, Rev. 6Freescale Semiconductor 1241The writes can be by the processor core or by DMA transfer. The writes continue until the end of the datastream is reached.29.3.4 Reading the checksumAfter writing of the data stream to the input register has been completed, the checksum is read from theoutput register (CRC_OUTP). The CRC_OUTP register includes the final checksum (signature)corresponding to the CRC_CSTAT register value with swap and inversion operations applied, if selectedvia the CRC_CFG register.In case of CRC-16-CCITT polynomial only the 16 least significant bits have meaning. The 16 mostsignificant bits are set to 0 during the computation.29.4 Register descriptionsTable 29-1. CRC register mapContext Address11 CRC_BASE for the MPC5644A is 0xFFE6_8000Register Location1CRC_BASE + 0x0000 CRC Configuration Register (CRC_CFG) on page29-1242CRC_BASE + 0x0004 CRC Input Register (CRC_INP) on page29-1243CRC_BASE + 0x0008 CRC Current Status Register (CRC_CSTAT) on page29-1244CRC_BASE + 0x000C CRC Output Register (CRC_OUTP) on page29-12452CRC_BASE + 0x0010 CRC Configuration Register (CRC_CFG) on page29-1242CRC_BASE + 0x0014 CRC Input Register (CRC_INP) on page29-1243CRC_BASE + 0x0018 CRC Current Status Register (CRC_CSTAT) on page29-1244CRC_BASE + 0x001C CRC Output Register (CRC_OUTP) on page29-12453CRC_BASE + 0x0020 CRC Configuration Register (CRC_CFG) on page29-1242CRC_BASE + 0x0024 CRC Input Register (CRC_INP) on page29-1243CRC_BASE + 0x0028 CRC Current Status Register (CRC_CSTAT) on page29-1244CRC_BASE + 0x002C CRC Output Register (CRC_OUTP) on page29-1245
