Enhancement Request: Create console command for adjusting ADC multi-sampling settings.

[LucidEye]

Hello,

I am using several analog sensors for various agricultural monitors and data loggers. I am noticing that the data signal from the ESP32's built-in ADC is very noisy and has a lot of "jitter" in the returned data. I am aware of the issues and limitations with the built-in ADC, not truly linear, and quite noisy without filtering capacitors, but Espressif's own documentation recommends that BOTH the filtering capacitors AND multi-sampling be used whenever possible to get more "accurate" readings from the ADC and reduce the noise and jitter.
https://docs.espressif.com/projects/esp-idf/en/v4.3.3/esp32/api-reference/peripherals/adc.html#minimizing-noise

I was told in the Discord discussion that Tasmota does have multi-sampling implemented and enabled, however it is by default only set to 2-samples per reading. This setting can be found in the following file, lines 314-328:
https://github.com/arendst/Tasmota/blob/development/tasmota/tasmota_xsns_sensor/xsns_02_analog.ino

uint16_t AdcRead(uint32_t pin, uint32_t factor) { // factor 1 = 2 samples // factor 2 = 4 samples // factor 3 = 8 samples // factor 4 = 16 samples // factor 5 = 32 samples uint32_t samples = 1 << factor; uint32_t analog = 0; for (uint32_t i = 0; i < samples; i++) { analog += analogRead(pin); delay(1); } analog >>= factor; return analog; }

I was also informed that to change this setting requires an entire re-compile of the firmware? This really seems like a feature that is important enough that it should have a console command to expose this setting for easier adjustment. Is there such a command? If not I would like to request this as a feature enhancement if possible.

Thank you for any help or info on this.

[barbudor]

You pointed the right lines where factor defines the oversampling
But did you tried to look further to see value factor was set to ?

If you are using ADC_INPUT, the factor is set to 5 which means 32 readings
Not enough ?

[barbudor]

Stop
tasmota-4m is not for esp32

What exact device do you have and which binary are you running?

[LucidEye]

https://www.amazon.com/dp/B09Z7Q5LKQ?psc=1&ref=ppx_yo2ov_dt_b_product_details

[barbudor]

OK, so you need
http://ota.tasmota.com/tasmota32/tasmota32.bin

Same process but different url

[LucidEye]

Thanks again! Glad I caught your reply before flashing :-P

[LucidEye]

So just a quick follow-up. I still do not have the capacitors installed yet, but just with the multi-sampling set higher the signal is already much "cleaner"... less bounce and jitter.
Everything on the left of 17:00 is with the 2x multi-sampling, everything on the right is with the 32x multi-sampling...

So once I get the filter caps installed it should be even more of an improvement as the caps should attenuate most of the high-reading spikes.

Thank you so much once again :-)