Specifications

CY7C67200
Document Number: 38-08014 Rev. *J Page 62 of 93
Register Description
The SPI CRC Control register provides control over the CRC
source and polynomial value.
CRC Mode (Bits [15:14)
The CRCMode field selects the CRC polynomial as defined in
Tabl e 3 5 .
CRC Enable (Bit 13)
The CRC Enable bit enables or disables the CRC operation.
1: Enables CRC operation
0: Disables CRC operation
CRC Clear (Bit 12)
The CRC Clear bit will clear the CRC with a load of all ones. This
bit is self clearing and always reads ‘0’.
1: Clear CRC with all ones
0: No Function
Receive CRC (Bit 11)
The Receive CRC bit determines whether the receive bit stream
or the transmit bit stream is used for the CRC data input in full
duplex mode. This bit is a don’t care in half-duplex mode.
1: Assigns the receive bit stream
0: Assigns the transmit bit stream
One in CRC (Bit 10)
The One in CRC bit is a read-only bit that indicates if the CRC
value is all zeros or not.
1: CRC value is not all zeros
0: CRC value is all zeros
Zero in CRC (Bit 9)
The Zero in CRC bit is a read-only bit that indicates if the CRC
value is all ones or not.
1: CRC value is not all ones
0: CRC value is all ones
Reserved
All reserved bits must be written as ‘0’.
SPI CRC Value Register [0xC0D4] [R/W]
Figure 67. SPI CRC Value Register
Register Description
The SPI CRC Value register contains the CRC value.
CRC (Bits [15:0])
The CRC field contains the SPI CRC. In CRC Mode CRC7, the CRC value will be a seven bit value [6:0]. Therefore bits [15:7] are
invalid in CRC7 mode.
Table 35. CRC Mode Definition
CRCMode
[9:8]
CRC Polynomial
00 MMC 16-bit: X^16 + X^12 + X^5 + 1
(CCITT Standard)
01 CRC7 7-bit: X^7+ X^3 + 1
10 MST 16-bit: X^16+ X^15 + X^2 + 1
11 Reserved, 16-bit polynomial 1.
Bit # 15 14 13 12 11 10 9 8
Field CRC...
Read/Write R/W R/W R/W R/W R/W R/W R/W R/W
Default 1 1 1 1 1 1 1 1
Bit # 7 6 5 4 3 2 1 0
Field ...CRC
Read/Write R/W R/W R/W R/W R/W R/W R/W R/W
Default 1 1 1 1 1 1 1 1