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

# i2C OLED
i2c = I2C(scl=Pin(22), sda=Pin(21), freq=400000)
oled = ssd1306.SSD1306_I2C(128, 64, i2c)

# ADC config
adc = ADC(Pin(34))  # ADC on pin 34
adc.atten(ADC.ATTN_11DB)

while True:
    # Read ADC
    adc_value = adc.read()
    # Convert to voltage
    voltage = adc_value / 4095.0 * 3.6
    
    # Show voltage in screen
    oled.fill(0)
    oled.text("Voltage:", 0, 0)
    oled.text("{:.2f} V".format(voltage), 0, 20)
    oled.show()

    utime.sleep(5)