At+adc wrong values?


#1

Im having trouble reading voltage on my q24Plus module. Im using a PTC thermistor through a voltage divider and AUXV0 (pin 33) as input. When I read the voltage with at+adc? I get three values, the first is about 5500, which should be the battery voltage. But I know the VBATT is 3,9V. The last value is about 2450 which should be my AUXV0 value, but when I measure voltage with a multimeter I get 1,78V input to AUXV0. If I calculate the voltage with ADCvalue / 1024, I get too high voltages. How can this be? I also think the ADC is changing values even if the input voltage is stable. Isnt the ADC any good? I´m thinking of perhaps building a separate microcontroller with ADC to calculate temerature, but the best solution should be to be able to use the q24 for that…