R01UH0822EJ0100 Rev.1.00
Page 806 of 1041
Jul 31, 2019
RX13T Group
25. CRC Calculator (CRC)
25.4
Usage Notes
25.4.1
Module Stop Function Setting
Operation of the CRC calculator can be disabled or enabled using the module stop control register B (MSTPCRB). After
a reset, the CRC is in the module stop state. Register access is enabled by releasing the module stop state. For details,
refer to
section 11, Low Power Consumption
.
25.4.2
Note on Transmission
Note that the sequence of transmission for the CRC code differs according to whether transmission is LSB first or MSB
first.
Figure 25.6
LSB First and MSB First Data Transmission
CRCDIR
CRCDOR
1. CRC code
CRC code generation
After specifying the method for generation calculation, write data to CRCDIR register in the order of (1), (2), (3), and (4).
Output
15
7
7
0
0
0
0
7
0
0
0
0
7
7
7
7
(1)
CRC code (H)
CRC code
Output
7
7
0
0
0
0
0
0
7
7
7
7
2. Transmit data
CRC code (L)
(H)
(L)
(4)
(3)
(2)
(1)
(i) When transmission is LSB first
(ii) When transmission is MSB first
(1)
(2)
(3)
(4)
(H)
(L)
CRC code
CRCDIR
7
0
(2)
CRCDIR
7
0
(3)
CRCDIR
7
0
(4)
7
8
When transmitting 32-bit data