Siemens SIMATIC ET 200S Operating Instructions Manual page 168

1Count5V
3.7 Measurement Modes
The following figure illustrates the principle of continuous measurement using frequency
measurement as an example.
Figure 3-23
Gate Control
To control the 1Count5V, you have to use the gate functions.
Isochronous Mode
In isochronous mode, the 1Count5V accepts control bits and control values from the control
interface in each bus cycle and reports back the response in the same cycle.
In each cycle, the 1Count5V transfers a measured value and the status bits that were valid
at time T
The measurement starts and ends at time T
168
Principle of Continuous Measurement (Frequency Measurement Example)
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Operating Instructions, 06/2010, A5E00124867-07
Technological Functions