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

# ---- CONSTANTES (divisor simulado) ----
R1 = 100000
R2 = 27000
VREF = 3.3

# ---- OLED ----
i2c = I2C(0, scl=Pin(22), sda=Pin(21))
oled = ssd1306.SSD1306_I2C(128, 64, i2c)

# ---- ADC ----
adc = ADC(Pin(34))
adc.atten(ADC.ATTN_11DB)
adc.width(ADC.WIDTH_12BIT)

# ---- FILTRO EMA ----
class FiltroEMA:
    def __init__(self, alpha=0.15):
        self.alpha = alpha
        self.valor = None

    def filtrar(self, x):
        if self.valor is None:
            self.valor = x
        else:
            self.valor = self.alpha * x + (1 - self.alpha) * self.valor
        return self.valor

filtro = FiltroEMA()

# ---- LOOP ----
while True:
    raw = adc.read()
    vadc = (raw / 4095) * VREF
    vin = vadc * (R1 + R2) / R2
    vin_f = filtro.filtrar(vin)

    oled.fill(0)
    oled.text("BATERIA", 34, 0)
    oled.text("RAW: {}".format(raw), 0, 22)
    oled.text("V: {:.2f} V".format(vin_f), 0, 42)
    oled.show()

    time.sleep(0.3)