Memory Tag - Back Timestamping delayed data

Ignition
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1

Hello,

I am trying to write to various memory tags with slightly delayed data (10-30 minutes) that is also sometimes out of order. Consider the following example:

Example Tag Current Value:
last value: 10
last timestamp: 12:00

Now the delayed data comes in at 12:30:
Delayed Data:
value:15
timestamp: 12:10

If I write the new datapoint via system.tag.writeblocking, I see the value and timestamp enter the tag's value/timestamp fields correctly. However, when plotted or viewed in the tag history the timestamp is when the tag was written which is incorrect.

If I try to write the new datapoint via system.tag.storetaghistory, I don't see it show up anywhere.

There is also the case where data comes in out of order. For example I may receive the 12:20 data before the 12:10 data. Any tips on how to approach this issue?

2

Tag Provider's have an "Allow Backfill" setting that defaults to false. Try setting it to true and see if the behavior changes.

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3

Hi,
I left the Back-fill in the default setting and use this:

from com.inductiveautomation.ignition.common.model.values import BasicQualifiedValue, QualityCode
tagpath = yourTagpath
qval = BasicQualifiedValue(value = yourValue , quality=QualityCode.Good, timestamp = yourTimestamp)
system.tag.writeBlocking([tagpath], [qval])