from machine import Pin, ADC, PWM, I2C
from time import sleep
import ssd1306

#DO_PIN = Pin(16, Pin.IN)
gas_sensor = ADC(Pin(32))
buzzer = PWM(Pin(23, Pin.OUT))
i2c = I2C(0, scl=Pin(14), sda=Pin(12))
oled_width = 128
oled_heigth = 64
display = ssd1306.SSD1306_I2C(oled_width, oled_heigth, i2c)

gas_sensor.atten(ADC.ATTN_11DB)
gas_sensor.width(ADC.WIDTH_12BIT)
flag = 3000

def set_buzzer(freq, periodo):
    buzzer.freq(freq)
    buzzer.duty(50)
    sleep(periodo)

while True:
    gas_val = gas_sensor.read()
    display.fill(255)
    if(gas_val > flag):
        print("A concentração de gás está alta!")
        set_buzzer(300,0.1)
    else:
        set_buzzer(1,0)

    display.setTextSize(1)
    display.text("Quantidade gás: " + str(gas_val), 0,55, 0)
    display.show()