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CHAPTER 24 OPTION BYTE
User’s Manual U19780EJ2V0UD
590
Here is an example of description of the software for setting the option bytes.
OPT CSEG
AT
0080H
OPTION: DB
30H
; Enables watchdog timer operation (illegal access detection operation),
; Window open period of watchdog timer: 50%,
; Overflow time of watchdog timer: 2
10
/f
RL
,
; Internal low-speed oscillator can be stopped by software.
DB
00H
; 1.59 V POC mode
DB
00H
; Reserved area
DB
00H
; Reserved area
DB
00H
; On-chip debug operation disabled
Remark
Referencing of the option byte is performed during reset processing. For the reset processing timing,
see
CHAPTER 21 RESET FUNCTION
.