K60P100M100SF2RM Datasheet, PDF (761/1809 Pages) Freescale Semiconductor, Inc – K60 Sub-Family Reference Manual

Chapter 31 Cyclic redundancy check (CRC)
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Figure 31-7. Transpose type 11
NOTE
For 8-bit and 16-bit write accesses to the CRC data register, the
data is transposed with zeros on the unused byte or bytes
(taking 32 bits as a whole), but the CRC is calculated on the
valid byte(s) only. When reading the CRC data register for a
16-bit CRC result and using transpose options 10 and 11, the
resulting value after transposition resides in the CRC[HU:HL]
fields. The user software must account for this situation when
reading the 16-bit CRC result, so reading 32 bits is preferred.
31.3.4 CRC result complement
When the CTRL[FXOR] bit is set, the checksum is complemented: The CRC result
complement function outputs the complement of the checksum value stored in the CRC
data register every time the CRC data register is read. When the CTRL[FXOR] bit is
cleared, reading the CRC data register accesses the raw checksum value.
K60 Sub-Family Reference Manual, Rev. 6, Nov 2011
Freescale Semiconductor, Inc.
761