There are a few items for Sampling Mode Setting.
Please refer Function
Reference to know more details of each functions.
You can set only Standalone mode with API-CNT(LNX).
There is CntSetStandAlone
function for compatibility of source file with API-CNT(WDM).
You can select Totalizing Counter or Difference Counter by CntSetCounterMode function.
Totalizing counter mode
The counter works as a usual UP/DOWN counter.
Difference counter mode
The difference from the last count value
is used as sampling data.
The frequency can be measured by using this mode for sampling at a certain
period.