- Thu Apr 04, 2019 8:14 am
#81557
Hi i figured out the problem.
the esp82xx connects at time of mesurement the vcc an voltagedivider at a0 . 10k up to internal reference and 10 k down ti gnd. so it works with an esp12x or esp8266 fine and perfect.
in case of use an nodemcu is " extern " an 100k pulldown connectet !
bacause that you get 2.9 volt istaed the in my case correct 3.25 volt
Its an right and legitim to korrect the value depends on the external part are connectet.
At nodemcu you can easely the mesured value by 0,9
example:
float vcc = ESP.getVcc() / 900.0; //normaly 1000.0 - nodemcu has a pulldown 100k at adc0 therefor 900 !!
lcd_left.setCursor(0,3);
lcd_left.print(vcc);
regards from jens