from machine import Pin, ADC 
from utime import sleep
from picozero import Speaker       
import math   

led = Pin(4, Pin.OUT)
sensor_gas = ADC(26)              
buzzer = Speaker(1)
RL = 5000                         
R0 = 10000                        

m = -0.42                         
b = 1.92                        

while True:
    leitura = sensor_gas.read_u16()                         
    tensao = (leitura / 65535) * 3.3
    rs = (3.3 - tensao) * RL / tensao                      
    razao = rs / R0                                         
    ppm = 10 ** ((math.log10(razao) - b) / m)               
    print("Nivel de gas e fumaça:", ppm)   

    if ppm >= 30000:
        led.on ()
        buzzer.on ()
    
    else:
        led.off()
        buzzer.off()
    sleep(1)