WeMos D1 mini ADC temperature wrong

[Duvio]

PROBLEM DESCRIPTION

A clear and concise description of what the problem is.
When connecting an NTC thermistor to A0 with an external voltage divider on a WeMos D1 mini and selecting ADC temp for that pin in the module configuration, the calculated temperature is wrong. I suspect this is because this board already has an internal voltage divider.

REQUESTED INFORMATION

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• Device used (e.g., Sonoff Basic): _____
• Tasmota binary firmware version number used: 13.0.0
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TO REPRODUCE

Steps to reproduce the behavior:
3.3v ---- NTC thermistor ---- A0 ---- resistor ---- GND
The resistor is 10kO and the thermistor is 10kO at 25°C and b=3435.
In module configuration set the module to generic and afterwards A0 to ADC temp.

EXPECTED BEHAVIOUR

A clear and concise description of what you expected to happen.
The temperature to be displayed correctly.

SCREENSHOTS

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ADDITIONAL CONTEXT

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[sfromis]

If the calculated temperature is not what you'd want, it is up to you to use AdcParam to get it to be better. You may be right about the voltage divider, but that's not something you should expect Tasmota to fix for you.

[Duvio]

If the calculated temperature is not what you'd want, it is up to you to use AdcParam to get it to be better. You may be right about the voltage divider, but that's not something you should expect Tasmota to fix for you.

I already set the values using AdcParam correctly, the value shown is still wrong. Do you mean i have to manually factor in the voltage dividers and tweak the AdcParam accordingly?

[barbudor]

The Tasmota NTC is meant for a NTC connected exactly like in the schematic shown in the code of the analog driver (sorry, it's in the ino code as comment, not in the docs, PR welcomed) which how it is connected on the Shelly 1

Any other connection circuit may need adaptation.

[lalo-uy]

There is a problem in adc term code with wemos D1. The code for ESP8266 asume the adc input range of 1V and 3.3v for ESP32. That do not takes into account the wemos divider. I reported some months ago and patched my own code. In line 529 remove the ANALOG_V33 Rt = (double)Adc[idx].param1 * (ANALOG_RANGE * ANALOG_V33 - (double)adc) / ( double)adc; El El dom, 6 de ago. de 2023 a la(s) 10:51, Barbudor < ***@***.***> escribió:

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The Tasmota NTC is meant for a NTC connected exactly like in the schematic shown in the code of the analog driver (sorry, it's in the ino code as comment, not in the docs, PR welcomed) which how it is connected on the Shelly 1 Any other connection circuit may need adaptation. — Reply to this email directly, view it on GitHub <#19271 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ACXBW4K644KJMH35D44DNVDXT6OPFANCNFSM6AAAAAA3F5OJT4> . You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>