from machine import ADC, Pin
from time import sleep
import math

ADC_PIN = 26        # GP26 = ADC0 (mude se estiver em GP27/GP28)
VREF = 3.3
R_FIXED = 10000     # resistor fixo (10k)
R0 = 10000          # NTC 10k em 25°C
BETA = 3950         # Beta do NTC (ajuste se necessário)
T0 = 298.15         # 25°C em Kelvin

adc = ADC(Pin(ADC_PIN))

def calc_r_ntc(vout):
    return R_FIXED * (vout / (VREF - vout))


def r_to_celsius(r_ntc):
    inv_t = (1 / T0) + (1 / BETA) * math.log(r_ntc / R0)
    t_k = 1 / inv_t
    return t_k - 273.15

while True:
    raw = adc.read_u16()  # 0..65535
    vout = (raw / 65535) * VREF
    r_ntc = calc_r_ntc(vout)
    temp_c = round(r_to_celsius(r_ntc), 1)

    print("-> Valor analógico do sensor:", raw, "\n-> Temperatura:", temp_c, "°C\n")

    sleep(2)