Oversampling - Siemens SIMATIC ET 200SP Manual

4.4

Oversampling

Function
Oversampling is the acquisition of data in constant bus cycle segments (sub-cycles). The
configured number n of sub-cycles corresponds to one PROFINET bus cycle.
Oversampling is useful whenever you require acquisition of data with high time resolution but
without using an extremely short PROFINET bus cycle and thus fast CPU cycles.
With oversampling, a PROFINET bus cycle is divided into constant bus sub-cycles:
● One measured value is acquired in each sub-cycle.
● The minimum PROFINET bus cycle is 250 µs. Only a subset of functions is available for
shorter sub-cycles.
● The shortest possible sub-cycle is 50 μs.
● You can configure oversampling:
– For channel 0 (1-channel operation)
– For channel 0/1 (2-channel operation)
● The number of sub-cycles can be set as follows:
– From 2 to 16 for one channel
– From 2 to 8 for two channels
Requirement
Oversampling is only possible when isochronous mode is set.
Configuration
You configure oversampling with the following parameter:
● Sampling rate
Note
Do not use a reduction ratio for blocks in the case of configuration with oversampling in the
runtime groups of your user program. This will ensure that the data processing in the user
program of the CPU is synchronized with the acquisition on the module.
Analog input module AI 2xU/I 2-/4-wire HS (6ES7134-6HB00-0DA1)
Manual, 09/2018, A5E03576060-AF
Parameters/address space
4.4 Oversampling
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