AVL F-FEM-CNT - Description of Function; Evaluation of Edges

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Operation
F-FEM-CNT — User’s Guide
4.1.4 Description of Function
This measurement method does not only count the pulses delivered by the pulse
generator but also records exactly the time between the pulses. Thus, it is no
longer necessary to strictly observe the time interval between two sampling
points (gate time).
4.1.5 Evaluation of Edges
Every time the level of a digital signal changes we call this an edge. A level
change from logic low to logic high (high-pulse) is a rising edge, on the other side
a level change from logic high to logic low (low-pulse) is a falling edge.
The evaluation of levels to countable pulses can happen either as:
 Single Edge Evaluation on page 36, or as
 Multi Edge Evaluation on page 36.
Fig. 21 Block diagram of a counter channel
Signal