Hi all,
Building up to the new firmware release 0.9.11 we have added a small feature that we believe can be handy for testing and improving temperature and humidity readings.
You can introduce a custom offset for temperature and humidity readings for both, the sensors on the Urban Board, or external sensors via the auxiliary port.
To check the offset currently implemented:
SCK > control temp cal
Current temperature offset: -1.00 (degC)
SCK > control hum cal
Current humidity offset: 3.50 (rh)
Default offsets: These offsets are calibrated based on internal tests on each hardware version. You can always modify them to suit your needs, or revert back to the default with control temp cal clear or control hum cal clear.
To modify, you can issue the control temp cal command followed by a the offset to add in float notation (for instance -10.0):
Check the calibration and read the current value:
SCK > control temp cal
Temperature: cal
Current temperature offset: -1.00 (degC)
SCK > read temp
Temperature: 25.95 C
Modify the temperature offset by -10.0 degC. Note that for the previous reading, there was already an offset of -1.00 degC, so now the offset will be -11.0 degC:
SCK > control temp cal -10.00
Temperature: cal -10.00
SCK > control temp cal
Current temperature offset: -11.00 (degC)
SCK > read temp
Temperature: 15.96 C
To revert to the previous value:
SCK > control temp cal clear
Set default offset: -1.00 (degC)
SCK > control temp cal
Current temperature offset: -1.00 (degC)
SCK > read temp
Temperature: 26.09 C
This all applies to the humidity readings:
control hum cal
Current humidity offset: 3.50 (rh)
SCK > read hum
Humidity: 63.06 %
Finally, in addition to this, external SHT3X sensors on the auxiliary bus such as this one. The documentation is now available in: Using the Shell - Smart Citizen Docs
Hope this works for you! Currently merged on the master branch, but to be released shortly on 0.9.11. Feedback welcome!