Temperature probe offset

Hi all.
I use a USB temperature and RH logger that feeds into Node Red. I managed to get as far as getting data but I'm in a pickle over the temperature probe: using the Buffer-parser, I managed to extract the proper message (unsigned 16 bit), and scale it to the proper decimal. But the value requires an offset of 200 and I can't for the life of me figure out how to do that (i.e. 206.5 is 6.5). Suggestions anyone ?

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You Don't say if it is a number or string. You should be able to parseFloat() and then simply minus 200.
e.g.

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I am dumbfounded by the stupidity of my own question... Thanks for indulging me with an actual, serious answer, it hurts just a bit less :slight_smile: