USB_dewpoint v2: probe1 and ambient inverted? - by: fenriques

There's a weird behavior in USB_dewpoint v2 driver: both in manual and automatic mode when power is applied to an output (e.g. Channel 1), the ambient temperature goes up, the Channel 1 values remains stable and the Dewpoint increases.
That is strange because I would expect Channel 1 to increase, Ambient to stay (more or less) stable and Dewpoint stable.

Is it possible that values for Channel 1 and Ambient temperatures are inverted?
As a proof of this I tried to calculate dew point given temperature and humidity: using Humidity and Ambient (as it should be) I get a wrong dew point. Using Humidity and Channel 1 I get always the Dew Point shown by the driver.
Moreover as additional proof, in automatic mode, the heating never stops: Channel 1 doesn't increases, but Ambient increases and raises Dew point. So the gap between the two increases and power is always 100% and never stops.

My understanding is that as INDI driver just reads values from device, so it's not an INDI driver issue but a firmware issue (v 1705) on USB_dewpoint.
In fact dewpoint value is not calculated by the driver but read from the device.
Does anyone else experienced the same?

Thanks
Ferrante

PS: yes, I checked that I connected Ambient probe and Temp1 probe in the right positions on the device.

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This is the order of parameter read by the INdi driver in usb_dewpoint.h:
// Status response is like:
// ##22.37/22.62/23.35/50.77/12.55/0/0/0/0/0/0/2/2/0/0/4**

// Fields are in order:
// temperature ch 1
// temperature ch 2
// temperature ambient
// relative humidity
// dew point
// output ch 1
// output ch 2
// output ch 3
// calibration ch 1
// calibration ch 2
// calibration ambient
// threshold ch 1
// threshold ch 2
// auto mode
// outputs ch 2 & 3 linked
// aggressivity