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R01UH0336EJ0102 Rev.1.02
Page 381 of 1538
Jul 17, 2014
V850E2/PG4-L
Section 11 Data CRC Function A (DCRA)
11.3 Functional Description
The data CRC function A generates a CRC (cyclic redundancy check) of an
arbitrary data block length. The data is forwarded to the data CRC function in
8-, 16-, or 32-bit units. The CRC polynomial can either be selected for 32-bit
Ethernet or 16-bit CCITT. The initial starting value must be set at the
DCRAnCOUT register before the first write access to the CRC input register
(DCRAnCIN) is performed.
The flow chart below shows the CRC generating procedure.
Figure 11-2
Data CRC Function A Flow Diagram
Note
For the settings of the individual registers and points for caution regarding the
settings, see Section 11.4.2, DCRA Registers Details.
Start
End
Write to DCRAnCTL.
Write to DCRAnCIN.
CRC code generation
Read from DCRAnCOUT.
Input data?
No
Yes
Write to DCRAnCOUT
with the initial starting value.