PXS20RM Datasheet, PDF (288/1368 Pages) Freescale Semiconductor, Inc – PXS20 Microcontroller

Cyclic Redundancy Checker (CRC) Unit
Table 14-2. CRC_CFG field descriptions
Field
Description
POLYG
(for cut1)
Polynomial selection
0 CRC-CCITT polynomial
1 CRC-32 polynomial.
This bit can be read and written by the software.
This bit can be written only during the configuration phase.
POLYG
(for cut2/3)
Polynomial selection
00 CRC-CCITT polynomial
01 CRC-32 polynomial
10 CRC-8 polynomial
11 Reserved
This field can be read and written by the software.
This field can be written only during the configuration phase.
SWAP
SWAP selection
0: No swap selection applied on the CRC_OUTP content
1: Swap selection (MSB -> LSB, LSB -> MSB) applied on the CRC_OUTP content. In case of
CRC-CCITT polynomial the swap operation is applied on the 16 LSB bits.
This bit can be read and written by the software.
This bit can be written only during the configuration phase.
INV
INV selection
0: No inversion selection applied on the CRC_OUTP content
1: Inversion selection (bit x bit) applied on the CRC_OUTP content. In case of CRC-CCITT polynomial
the inversion operation is applied on the 16 LSB bits.
This bit can be read and written by the software.
This bit can be written only during the configuration phase.
14.5.2 CRC Input Register (CRC_INP)
Offset: 0x4 + (N–1)0x10
Access: User read/write
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
R
INP[31:16]
W
Reset 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
R
INP[15:0]
W
Reset 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Figure 14-4. CRC Input Register (CRC_INP)
14-4
PXS20 Microcontroller Reference Manual, Rev. 1
Freescale Semiconductor