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09/16/2021
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Hello colleagues!
Now I am interested in the history read Raw service OPC UA.
The specification does not explicitly say what UNSPECIFIED is equal to.
In https://reference.opcfoundatio…..4/docs/6.4 part 6.4.3.1 says that startTime and endTime “Set to default value of DateTime.MinValue if no specific end time is specified”.
Well we know that Datetime is a 64-bit signed integer, that is, Datetime.MinValue=-9223372036854775808?
But if you look here https://reference.opcfoundatio…..cs/5.2.2.5 it turns out that Datetime.MinValue=-1 (1601-01-01 12:00AM UTC)?
I have looked at various implementations of opensource projects and in them UNSPECIFIED is defined differently.
So is there a TIMESTAMP UNSPECIFIED?
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05/30/2017
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The formal definition of DateTime.MinValue is in Part 6:
https://reference.opcfoundatio…..docs/5.1.4
As you can see the exact definition changes depending on the development platform.
But the UABinary wire encoding will always be 0.
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