'''
ESP32analog input converter（analog to digital converter，abbreviationADC）Can be used as32~39foot，
The input voltage is between0V~3.6V、12bit sampling，The quantized value is between0~4095。
ADC.ATTN_11DB：11dB attenuation，Input voltage upper limit3.6V。
ADC.WIDTH_12BIT：12Bit（212，0~4095）
'''

from machine import Pin, ADC
from time import sleep

LDR = ADC(Pin(26, Pin.IN))
LDR.atten(ADC.ATTN_11DB)
led1 = Pin(22, Pin.OUT)
led2 = Pin(19, Pin.OUT)
led3 = Pin(4, Pin.OUT) 

while True:
    if LDR.read() < 2500:
        #led1.value(0)
        led1.off()
        led2.off()
        led3.off()
    elif LDR.read() < 3000 :
        #led1.value(1)
        led1.on()
        led2.off()
        led3.off()
    elif LDR.read() < 3500 :
        led1.on()
        led2.on()
        led3.off()
    elif LDR.read() < 4000 :
        led1.on()
        led2.on()
        led3.on()

    sleep(0.5)
    print(LDR.read())