Cypress S6J3200 Series, Руководство пользователя

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CHAPTER 25:Programmable CRC
974 S6J3200 Series Hardware Manual Document Number: 002-04852 Rev. *G
4.6.
CRC Read Register (CRCn_RD)
The CRC Read Register (CRCn_RD) contains the final checksum of the data written to the CRCn_WR
register.
CRC Read Register (CRCn_RD)
BIT_OFFSET 31 30 29 28 27 26 25 24
BIT_NAME CRCRD[31] CRCRD[30] CRCRD[29] CRCRD[28] CRCRD[27] CRCRD[26] CRCRD[25] CRCRD[24]
ACCESS_TYPE R,W R,W R,W R,W R,W R,W R,W R,W
PROT_TYPE Rp/Wp
INITIAL_VALUE 0 0 0 0 0 0 0 0
BIT_OFFSET 23 22 21 20 19 18 17 16
BIT_NAME CRCRD[23] CRCRD[22] CRCRD[21] CRCRD[20] CRCRD[19] CRCRD[18] CRCRD[17] CRCRD[16]
ACCESS_TYPE R,W R,W R,W R,W R,W R,W R,W R,W
PROT_TYPE Rp/Wp
INITIAL_VALUE 0 0 0 0 0 0 0 0
BIT_OFFSET 15 14 13 12 11 10 9 8
BIT_NAME CRCRD[15] CRCRD[14] CRCRD[13] CRCRD[12] CRCRD[11] CRCRD[10] CRCRD[9] CRCRD[8]
ACCESS_TYPE R,W R,W R,W R,W R,W R,W R,W R,W
PROT_TYPE Rp/Wp
INITIAL_VALUE 0 0 0 0 0 0 0 0
BIT_OFFSET 7 6 5 4 3 2 1 0
BIT_NAME CRCRD[7] CRCRD[6] CRCRD[5] CRCRD[4] CRCRD[3] CRCRD[2] CRCRD[1] CRCRD[0]
ACCESS_TYPE R,W R,W R,W R,W R,W R,W R,W R,W
PROT_TYPE Rp/Wp
INITIAL_VALUE 0 0 0 0 0 0 0 0
[bit31:0] CRCRD[31:0]: CRC Read Data
The CRC Read Register contains the result (final checksum) of the CRC calculation after
post-processing (applying CRCn_CFG:ROBIT, CRCn_CFG:ROBYT, and CRCn_FXOR settings).
Writing any value on CRCn_RD register changes its content and it does not affect CRC calculation.
Note:
−
The polynomial length (CRCn_CFG:LEN) provides the length of the final checksum. If the
polynomial length is less than 32-bit, then bits not belonging to the checksum are "0" (in case the
invalid bits of the CRCn_FXOR register are not programmed to "0", then these bits in CRCn_RD
register might also be "1"). The bit/byte reflection settings (CRCn_CFG:ROBIT/ROBYT) can
influence the checksum in CRCn_RD register. For the position of the checksum bits refer toTable
3-3.