Information

CRC_CRC field descriptions (continued)
Field Description
23–16
HL
CRC High Lower Byte
In 16-bit CRC mode (CTRL[TCRC] is 0), this field is not used for programming a seed value. In 32-bit
CRC mode (CTRL[TCRC] is 1), values written to this field are part of the seed value when CTRL[WAS] is
1. When CTRL[WAS] is 0, data written to this field is used for CRC checksum generation in both 16-bit
and 32-bit CRC modes.
15–8
LU
CRC Low Upper Byte
When CTRL[WAS] is 1, values written to this field are part of the seed value. When CTRL[WAS] is 0, data
written to this field is used for CRC checksum generation.
7–0
LL
CRC Low Lower Byte
When CTRL[WAS] is 1, values written to this field are part of the seed value. When CTRL[WAS] is 0, data
written to this field is used for CRC checksum generation.
30.2.2 CRC Polynomial register (CRC_GPOLY)
This register contains the value of the polynomial for the CRC calculation. The HIGH
field contains the upper 16 bits of the CRC polynomial, which are used only in 32-bit
CRC mode. Writes to the HIGH field are ignored in 16-bit CRC mode. The LOW field
contains the lower 16 bits of the CRC polynomial, which are used in both 16- and 32-bit
CRC modes.
Address: CRC_GPOLY is 4003_2000h base + 4h offset = 4003_2004h
Bit 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
R
HIGH LOW
W
Reset
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 1 0 0 0 0 1
CRC_GPOLY field descriptions
Field Description
31–16
HIGH
High Polynominal Half-word
Writable and readable in 32-bit CRC mode (CTRL[TCRC] is 1). This field is not writable in 16-bit CRC
mode (CTRL[TCRC] is 0).
15–0
LOW
Low Polynominal Half-word
Writable and readable in both 32-bit and 16-bit CRC modes.
Memory map and register descriptions
K20 Sub-Family Reference Manual, Rev. 2, Feb 2012
572 Freescale Semiconductor, Inc.