from machine import ADC
import time
import math

adc = ADC(26)


VCC = 3.3
R_REF = 10000
BETA = 3950
T0  = 298.15

def read_ntc_temperature():

    adc_value =  adc.read_u16()

    voltage = adc_value*(VCC/65535)



    if voltage == 0:
        return None

 
    resistance_ntc = R_REF*(VCC/voltage-1)


    if resistance_ntc<=0:
        return None


    temp_kelvin = 1/(1/T0+math.log(resistance_ntc/R_REF)/BETA)


    temp_celsius=temp_kelvin-273.15
    return temp_celsius


while True:
    temperature=read_ntc_temperature()
    if temperature is not None:
         print("Temperature:{:.2f} °C".format(temperature))
    else:
        print("Sensor error or invalid reading.")
    time.sleep(1)