Siemens 6ES7131-6BF00-0DA0 - Page 51

Oversampling (OVS) operating mode
5.2 Parameters/address space
Digital input module DI 8x24VDC HS (6ES7131‑6BF00‑0DA0)
Manual, 03/2015, A5E35243810-AA
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5.2
Parameters/address space
5.2.1
Oversampling
Function
Oversampling means detecting data in equidistant time subcycles. In doing so, the
configured number of subcycles corresponds to one data cycle (send clock).
Oversampling always makes sense when you need to detect data with a high time resolution
but without wanting to use a very short data cycle.
With the oversampling function, a send clock is divided into equidistant subcycles:
● Each subcycle detects an 8-bit value.
● A subcycle is at least 7.8125 μs in length.
● Subcycles are possible in steps from 2 to 32 (sampling rate).
Requirement
The interface module or CPU, with which the module is used, must support isochronous
mode.
Sampling interval
The duration of a subcycle is the sampling interval. The cycle time T (send clock) for
isochronous mode is specified in the configuration software. This time, divided by the
configured sampling rate n
Sample
, yields the sampling interval t
Sample
of the module.
Example calculation:
Figure 5-3 Example of calculating the sampling interval