4. Functions
CNT-3208M-PE
59
Counter error
Counter errors are classified into three types: digital filter error, abnormal input error, and continuity
alarm error.
Digital filter error
When a signal faster than the digital filter setting is input to phase-A or B, it is reported as a digital filter
error. The report method is a status report (latch/clear), interrupt, or external output (one-shot pulse).
For the digital filter error, the levels of input signals are monitored according to the filter source clock
signal the period of which is half the digital filter setting. If the monitor fails to detect the same level
twice or more consecutively, a digital filter error is detected.
Note, however, that no filter error occurs when the input signal frequency is equal or close to an integer
multiple of the filter source clock frequency.
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When a signal faster than the digital filter setting is input
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Noise is generated.
Figure 4.16. Filter error (Set to 0.2
μsec)
0
0
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100nsec
Even when the input signal is less than 200 nsec,
no filter error occurs as long as the input signal frequency is
an integer multiple of the source clock frequency.
When the signal is less than 200 nsec, a filter error is reported.
When the signal is not less than 200 nsec,
counting is performed normally.
Filter source clock
Phase-A/Phase-B
input signal
50nsec
Phase-A/Phase-B
input signal
Phase-A/Phase-B
input signal
Summary of Contents for CNT-3208M-PE
Page 7: ...vi CNT 3208M PE ...
Page 15: ...1 Before Using the Product 8 CNT 3208M PE ...
Page 30: ...2 Setup CNT 3208M PE 23 3 Click on the End button to finish condition setting Click on End ...
Page 35: ...2 Setup 28 CNT 3208M PE ...
Page 71: ...4 Functions 64 CNT 3208M PE ...