The device driver fundamentally works ok, however I don't get the results from the datasheets specifications.
What can I do, or where are the bottlenecks?
In general this is a none trivial question!
Trying to answer it requires much more detailed information about your application, electrical circuit and overall system design.
Let me try to give some examples:
There can be various reasons, however most likely they are related to software and system design.
A few things to check:
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