Datasheet

Rev. 3.00, 03/04, page 433 of 830
14.11.4 Note on CRC Operation Circuit
Note that the sequence to transmit the CRC code differs between LSB-first transmission and
MSB-first transmission.
CRCDIR
CRCDORH
CRCDORL
1. CRC code generation
2. Transmission data
(i) LSB-first transmission
CRC code generation
After specifying the operation method, write data to CRCDIR in the sequence of (1) → (2) → (3) → (4).
CRC code
Output
7
770 0
0
0
70
00 0777
7
(1) → (2) → (3) → (4)
(5)
(6)
(1)(2)(3)(4)
(6)
(5)
(ii) MSB-first transmission
CRC code
Output
77000000777
7
(6)(5)(4)(3)
(2)
(1)
Figure 14.50 LSB-First and MSB-First Transmit Data