def do_connect():

        import network

        sta_if = network.WLAN(network.STA_IF)

        ap_if = network.WLAN(network.AP_IF)

        if ap_if.active():

                ap_if.active(False)

        if not sta_if.isconnected():

                print('connecting to network...')

        sta_if.active(True)

        sta_if.connect('MicroPython', '12345678') #wifi的SSID和密码

        while not sta_if.isconnected():

                pass

        print('network config:', sta_if.ifconfig())

        do_connect()

        gc.collect()

from simple import MQTTClient

from machine import Pin

import machine

import micropython

# ESP8266 ESP-12 modules have blue, active-low LED on GPIO2, replace

# with something else if needed.

led = Pin(2, Pin.OUT, value=1)

# Default MQTT server to connect to

SERVER = "183.230.40.39"

CLIENT_ID = "4070825"

TOPIC = b"micropython1"

username='76013'

password='micropythonespmp01'

state = 0

def sub_cb(topic, msg):

    global state

    print((topic, msg))

    if msg == b"on":

            led.value(0)

            state = 1

            print("1")

    elif msg == b"off":

            led.value(1)

            state = 0

            print("0")

    elif msg == b"toggle":

            # LED is inversed, so setting it to current state

            # value will make it toggle

            led.value(state)

            state = 1 - state

def main(server=SERVER):

    c = MQTTClient(CLIENT_ID, server,6002,username,password)

    # Subscribed messages will be delivered to this callback

    c.set_callback(sub_cb)

    c.connect()

    c.subscribe(TOPIC)

    print("Connected to %s, subscribed to %s topic" % (server, TOPIC))

    try:

            while 1:

                    #micropython.mem_info()

                    c.wait_msg()

    finally:

            c.disconnect()

import mqtt

mqtt.main()