SensorTile.box #3: A small, portable weather station

Eleon BORLINI · ‎2019-09-25

The first example application we see is the Barometer. It's on of the simplest applications because it consists only of Inputs (the Sensors) and one Output (stream to BLE). No operations (called in this case "functions") are performed on the data in this case. Our small weather station is therefore composed by:

Altimeter / pressure sensor (LPS22HH)
Digital temperature sensor (STTS751)
Humidity sensor (HTS221)

Data are acquired, transmitted continuously via BLE and finally displayed real-time on the phone screen, as shown here below �?�

Eleon BORLINI · ‎2019-09-25

Btw quite low pressure, quite bad weather...

Bill Dempsey · ‎2019-09-29

With such a low reading on the barometer, did you remember to recalibrate it after soldering? I notice the ST parts always read very low after install. If you did recalibrate, what was your offset value? Can you elaborate on the method you use to calibrate post-solder?

Eleon BORLINI · ‎2019-09-30

Hi Bill, you have to consider the barometric formula for the pressure calculation, which takes into account the altitude above mean sea level. Regards

Bill Dempsey · ‎2019-09-30

Well that's a non-answer if I've ever seen one. I asked you specifically if you re-calibrated. Why not answer the question? What was your method? Sending me a link to Wikipedia shows you might not have done the work properly! That's a deferral. Bzzzzz.. Fail

Eleon BORLINI · ‎2019-09-30

Means that you have to consider that you are not at sea level and you have to take into account the altitude (usually the average sea-level pressure is 1013.25 mbar). Today in Milano-Agrate (165mt) is 1010 mbar avg-sea level. Applying the (simplified) formula, from the link above:

with the proper conversion you get about 990mbar value.

Regards