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CHAPTER 16 INTERRUPT AND TEST FUNCTIONS
User’s Manual U11302EJ4V0UM
The noise eliminator sets the interrupt request flag (PIF0) to 1 if the input level of the sampled INTP0 is active
twice in succession.
Figure 16-7 shows the noise eliminator I/O timing.
Figure 16-7. Noise Eliminator I/O Timing (When Rising Edge Is Detected)
(a) When input is less than the sampling cycle (t
SMP
)
(b) When input is equal to or twice the sampling cycle (t
SMP
)
(c) When input is twice or more than the sampling cycle (t
SMP
)
t
SMP
Sampling clock
INTP0
PIF0
"L"
The PIF0 output remains low because the level of INTP0 is not high when
it is sampled.
t
SMP
Sampling clock
INTP0
PIF0
The PIF0 flag is set to 1 because the sampled INTP0 level is high twice
in succession in <2>.
<1>
<2>
t
SMP
Sampling clock
INTP0
PIF0
The PIF0 flag is set to 1 when INTP0 goes high twice in succession.