Cypress S6J3200 Series, Руководство пользователя

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CHAPTER 25:Programmable CRC
968 S6J3200 Series Hardware Manual Document Number: 002-04852 Rev. *G
4.2.
CRC Seed Register (CRCn_SEED)
The CRC Seed Register (CRCn_SEED) defines the initial value for the CRC checksum calculation.
CRC Seed Register (CRCn_SEED)
BIT_OFFSET 31 30 29 28 27 26 25 24
BIT_NAME SEED[31] SEED[30] SEED[29] SEED[28] SEED[27] SEED[26] SEED[25] SEED[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 1 1 1 1 1 1 1 1
BIT_OFFSET 23 22 21 20 19 18 17 16
BIT_NAME SEED[23] SEED[22] SEED[21] SEED[20] SEED[19] SEED[18] SEED[17] SEED[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 1 1 1 1 1 1 1 1
BIT_OFFSET 15 14 13 12 11 10 9 8
BIT_NAME SEED[15] SEED[14] SEED[13] SEED[12] SEED[11] SEED[10] SEED[9] SEED[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 1 1 1 1 1 1 1 1
BIT_OFFSET 7 6 5 4 3 2 1 0
BIT_NAME SEED[7] SEED[6] SEED[5] SEED[4] SEED[3] SEED[2] SEED[1] SEED[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 1 1 1 1 1 1 1 1
[bit31:0] SEED[31:0] : CRC SEED
CRCn_SEED contains the initial value for checksum calculation. If the seed value is not initialized for
the next operation (even if the seed value is identical to the previous operation), then calculation is
continued from the last state with the current checksum value as initial value. Initial value for seed
register is 0xFFFFFFFF.
Note:
−
The CRCn_SEED register should be configured with respect to the polynomial length
(CRCn_CFG:LEN). If the polynomial length is less than 32-bit, then the upper bits [31:LEN] must
be written to "0" by the programmer.