Omicron DANEO 400, Руководство пользователя

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DANEO 400
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Deglitching input signals
In order to suppress short spurious pulses a deglitching algorithm could be configured. The deglitch
process results in an additional dead time and introduces a signal delay. In order to be detected as a
valid signal level, the level of an input signal must have a constant value at least during the deglitch
time. The figure below illustrates the deglitch function.
Figure 29: Signal curve, deglitching input signals
Debouncing input signals
For input signals with a bouncing characteristic, a debounce function can be configured. This means
that the first change of the input signal causes the debounced input signal to be changed and then be
kept on this signal value for the duration of the debounce time.
The debounce function is placed after the deglitch function described above and both are realized by
the firmware of DANEO 400 and are calculated in real time.
The figure below illustrates the debounce function. On the right-hand side of the figure, the debounce
time is too short. As a result, the debounced signal rises to “high” once again, even
while the input
signal is still bouncing and does not drop to low level until the expiry of another period T
debounce
.
Figure 30: Signal curve, debounce input signals