from machine import Pin, PWM
import time

pwm_pin=PWM(Pin(14))
pwm_pin.freq(50)

#0.5 ms for 0 degree
#2.5ms for 180 degree

while True: 
    # 25 to 125 for 0 to 180 degree

    for x in range(0,180,1):
        y=(((2.5-0.5)/(180-0)*x+0.5)/20*1023)
        pwm_pin.duty(int(y))
        time.sleep_ms(500)

    for x in range(180,0,-1):
        y=(((2.5-0.5)/(180-0)*x+0.5)/20*1023)
        pwm_pin.duty(int(y))
        time.sleep_ms(500)