from machine import Pin, UART
import time

led = Pin(25, Pin.OUT)        
uart = UART(0, baudrate=15200) 

while True:
    if uart.any():
        choice = uart.read()
        if choice == 'o'
            led.value(1)
        elif choice == 'c'
            led.value(0)
           
    time.sleep(0.2)