Datasheet

RL78/L12 CHAPTER 23 SAFETY FUNCTIONS
R01UH0330EJ0200 Rev.2.00 782
Dec 13, 2013
23.3.2.2 CRC data register (CRCD)
This register is used to store the CRC operation result of the general-purpose CRC.
The setting range is 0000H to FFFFH.
After 1 clock of CPU/peripheral hardware clock (f
CLK) has elapsed from the time CRCIN register is written, the CRC
operation result is stored to the CRCD register.
The CRCD register can be set by a 16-bit memory manipulation instruction.
Reset signal generation clears this register to 0000H.
Figure 23-5. Format of CRC Data Register (CRCD)
Address: F02FAH After reset: 0000H R/W
Symbol 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
CRCD
Cautions 1. Read the value written to CRCD register before writing to CRCIN register.
2. If conflict between writing and storing operation result to CRCD register occurs, the
writing is ignored.
<Operation flow>
Figure 23-6. CRC Operation Function (General-Purpose CRC)
START
Write CRCD register to 0000H
Yes
No
End
Last address?
Address+1
Read CRCD register
Specify the start and end addresses
;
Store the start and end addresses in a
; general-purpose register.
; Initialize CRCD register
; Read 8-bit data of
corresponding address
; Execute CRC calculation for 8-bit data
Store data to CRCIN register
Read data
; Get CRC result
; Compare the value
; with the stored
; expected value and
; make sure that the
; values match.
1 clock wait (fCLK)