CHAPTER 17 INTERRUPT/EXCEPTION PROCESSING FUNCTION
User’s Manual U16896EJ2V0UD
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(a) Digital noise elimination control register (NFC)
The NFC register controls elimination of noise on the INTP3 pin. If f
XT
is used as the noise elimination
clock, the external interrupt function of the INTP3 pin can be used even in the IDLE/STOP mode.
This register can be read or written in 8-bit or 1-bit units.
Reset sets this register to 00H.
NFEN
Analog noise elimination
Digital noise elimination
NFEN
0
1
Setting of INTP3 pin noise elimination
NFC
NFSTS
0
0
0
NFC2
NFC1
NFC0
Number of samplings = 3 times
Number of samplings = 2 times
NFSTS
0
1
Setting of number of samplings of digital noise elimination
After reset: 00H R/W Address: FFFFF318H
f
XX
/64
f
XX
/128
f
XX
/256
f
XX
/512
f
XX
/1024
f
XT
NFC2
0
0
0
0
1
1
NFC1
0
0
1
1
0
0
NFC0
0
1
0
1
0
1
Selection of sampling clock
Setting prohibited
Other than above
Remark
f
XX
: Main clock frequency
f
XT
: Subclock frequency