xDrip, AAPS, and HIGH/LOW values

[Navid200]

An xDrip user who used a Dexcom sensor in companion app mode reported that when he had a pump malfunction resulting in his glucose going over 400mg/dL found out that AAPS was not receiving any values from xDrip.

This started me thinking on what xDrip does when the readings are very high or very low.
First, I decided to investigate the behavior when xDrip is a collector (not companion app).

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Fake data source (Collector)
I set up xDrip to use the fake data source. And I set it up so that it would go both to values over 400mg/dL as well as to values less than 40mg/dL.

xDrip:
xDrip data table:

AAPS:

When xDrip has a value greater than 400, it shows HIGH on screen. But, it broadcast 400 to AAPS.
When xDrip has values less than 40, it shows LOW on screen. But, it broadcast the value as is to AAPS.

There is an unexpected behavior. AAPS does not show any values less than 30mg/dL. It is not clear to me why this happens. However, when I look at the AAPS logs, I see that it has received the value and has given it a unique id and has considered it to be a valid reading.

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Companion app Mode
I have done no testing here. All I have to say is hand waving.

My understanding is that when a companion app shows a word (HIGH or LOW) instead of a value, xDrip cannot capture it.
I don't believe we can do anything about this.

We can possibly add a filter to look for the words HIGH and LOW and after detecting them, broadcast a corresponding value to AAPS.
The problem with that is that we will have to add filters for all languages. This is not practical.
I thought why don't we add settings in xDrip for the user to enter the words corresponding to HIGH and LOW in their language? Then, use those for capturing them in companion app mode.

I don't think that is such a good idea. It will complicate the code and a lot more that can break and become another open issue. And it takes a typo in the setting to completely make the solution useless.

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If you use xDrip in companion app mode, you need to now this limitation that when the official app shows HIGH or LOW, xDrip shows nothing and broadcast nothing.