from machine import Pin, ADC, I2C
from time import sleep
from math import log
import ssd1306



led = Pin(22, Pin.OUT)
button = Pin(12, Pin.IN, Pin.PULL_DOWN)
sensor = ADC(32)

i2c = I2C(0)
display = ssd1306.SSD1306_I2C(128, 64, i2c)


BETA=3950
T0 = 25

def init_display():
    display.fill(0)
    display.text('Temperature', 20, 0, 1)
    display.text('Sensor', 40, 8, 1)
    display.text('_______________________', 1, 16, 1)
    display.text('Push the button', 5, 32, 1)
    

while True:
    button_state = button.value()
    if button_state == 1:
        
        led.value(1)
        val_d = sensor.read()
        val_a = val_d *3.3/4095
        
        k=val_a/(3.3-val_a)
        
        T = 1 / (log(1 / (4095. / val_d - 1)) / BETA + 1.0 / (T0+273.15)) - 273.15
        
        #Possiamo scrivere T in funzione della tensione misurata (che compare nella costante k)
        #T = 1 / (log(k) / BETA + 1.0 / (T0+273.15)) - 273.15;

        #Calcolo della T a partire da una calibrazione statica 
        T2=(2.495-val_a)/0.034
      
        print('ADCout=', val_d,  '\tVm=', round(val_a,2),' V', '\tT = ', round(T,2), '°C', '\tT2=', round(T2,2), '°C')
        
        init_display()
        
        display.text('T = '+str(round(T,2))+' C', 25, 50, 1)
        display.show()

        led.value(0)
        sleep(1)
    else:
        led.value(0)
        init_display()
        display.show()