NEC UPD703116 User Manual page 713

Figure 14-14. Example of Noise Elimination Timing
Noise elimination clock
Input signal
Internal signal
Timers 1 to 3 rising
edge detection
Timers 1 to 3 falling
edge detection
Caution If there are three or less noise elimination clocks while the timers 1 to 3 input signals
are high level (or low level), the input pulse is eliminated as noise. If it is sampled at
least four times, the edge is detected as valid input.
CHAPTER 14 PORT FUNCTIONS
2 clocks 2 clocks 3 clocks 3 clocks 4 clocks
User's Manual U14492EJ5V0UD
4 clocks 5 clocks 5 clocks
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