Dalam tutorial ini, kami akan menunjukkan cara menggunakan MQTT untuk bertukar data antara hape android dan board mikrokontroler ESP8266 menggunakan firmware MicroPython.
Diagram Progam
- hape android sebagai publisher akan mengirim pesan text dengan topic “sooko/lampu” dan dengan message “on” atau “off”
- board esp 8266 sebagai subscriber mensubsribe topic “sooko/lampu” sehingga akan menerima pesan “on” atau “off” dan mengubahnya menjadi logic hight atau low
- setelah pesan diterima si esp8266 akan ganti mempublish dengan topic “loger” dengan message “saya hidup”
- sehinnga hape telah mensubsribe “loger” akan menerima pesan “saya hidup”
Catatan : tutorial ini kompatibel dengan board ESP32 dan ESP8266 .
Requirements
Persyaratan yang kita butuhkan meliputi:
- Laptop terinstal python 3
- text editor untuk menulis kode (vscode,kate,nano,pycharm,etc)
- Install esptool untuk flash frimaware micropython ke board
pip install esptool - Install adafruit-ampy untuk mendownload progam ke board
pip install adafruit-ampy
Flash micropython firmware
- download micropython firmware dan jalankan pada terminal
esptool.py --port /dev/ttyUSB0 erase_flash esptool.py --port /dev/ttyUSB0 --baud 460800 write_flash --flash_size=detect 0 esp8266-20191220-v1.12.bin
Mulai Menulis Progam
1. buat file bernama wifi.py
import network
class Wifi(object):
station = network.WLAN(network.STA_IF)
state="not_connect"
def __init__(self, *args, **kwargs):
super(Wifi,self).__init__(*args, **kwargs)
def connect(self,ssid,password):
print("connecting. . . . .")
if self.station.isconnected() == True:
self.state="connected"
return
self.station.active(True)
self.station.disconnect()
self.station.connect(ssid, password)
print("connecting")
while self.station.isconnected() == False:
self.state="connecting"
pass
self.state="connected"
print(self.station.ifconfig())
def disconnect(self):
self.station.disconnect()
print("forget")
def isconnected(self):
return self.state2. buat file bernama mqtt.py
try:
import usocket as socket
except:
import socket
import ustruct as struct
from ubinascii import hexlify
class MQTTException(Exception):
pass
class MQTTClient:
def __init__(self, client_id, server, port=0, user=None, password=None, keepalive=0,
ssl=False, ssl_params={}):
if port == 0:
port = 8883 if ssl else 1883
self.client_id = client_id
self.sock = None
self.server = server
self.port = port
self.ssl = ssl
self.ssl_params = ssl_params
self.pid = 0
self.cb = None
self.user = user
self.pswd = password
self.keepalive = keepalive
self.lw_topic = None
self.lw_msg = None
self.lw_qos = 0
self.lw_retain = False
def _send_str(self, s):
self.sock.write(struct.pack("!H", len(s)))
self.sock.write(s)
def _recv_len(self):
n = 0
sh = 0
while 1:
b = self.sock.read(1)[0]
n |= (b & 0x7f) << sh
if not b & 0x80:
return n
sh += 7
def set_callback(self, f):
self.cb = f
def set_last_will(self, topic, msg, retain=False, qos=0):
assert 0 <= qos <= 2
assert topic
self.lw_topic = topic
self.lw_msg = msg
self.lw_qos = qos
self.lw_retain = retain
def connect(self, clean_session=True):
self.sock = socket.socket()
addr = socket.getaddrinfo(self.server, self.port)[0][-1]
self.sock.connect(addr)
if self.ssl:
import ussl
self.sock = ussl.wrap_socket(self.sock, **self.ssl_params)
premsg = bytearray(b"\x10\0\0\0\0\0")
msg = bytearray(b"\x04MQTT\x04\x02\0\0")
sz = 10 + 2 + len(self.client_id)
msg[6] = clean_session << 1
if self.user is not None:
sz += 2 + len(self.user) + 2 + len(self.pswd)
msg[6] |= 0xC0
if self.keepalive:
assert self.keepalive < 65536
msg[7] |= self.keepalive >> 8
msg[8] |= self.keepalive & 0x00FF
if self.lw_topic:
sz += 2 + len(self.lw_topic) + 2 + len(self.lw_msg)
msg[6] |= 0x4 | (self.lw_qos & 0x1) << 3 | (self.lw_qos & 0x2) << 3
msg[6] |= self.lw_retain << 5
i = 1
while sz > 0x7f:
premsg[i] = (sz & 0x7f) | 0x80
sz >>= 7
i += 1
premsg[i] = sz
self.sock.write(premsg, i + 2)
self.sock.write(msg)
#print(hex(len(msg)), hexlify(msg, ":"))
self._send_str(self.client_id)
if self.lw_topic:
self._send_str(self.lw_topic)
self._send_str(self.lw_msg)
if self.user is not None:
self._send_str(self.user)
self._send_str(self.pswd)
resp = self.sock.read(4)
assert resp[0] == 0x20 and resp[1] == 0x02
if resp[3] != 0:
raise MQTTException(resp[3])
return resp[2] & 1
def disconnect(self):
self.sock.write(b"\xe0\0")
self.sock.close()
def ping(self):
self.sock.write(b"\xc0\0")
def publish(self, topic, msg, retain=False, qos=0):
pkt = bytearray(b"\x30\0\0\0")
pkt[0] |= qos << 1 | retain
sz = 2 + len(topic) + len(msg)
if qos > 0:
sz += 2
assert sz < 2097152
i = 1
while sz > 0x7f:
pkt[i] = (sz & 0x7f) | 0x80
sz >>= 7
i += 1
pkt[i] = sz
#print(hex(len(pkt)), hexlify(pkt, ":"))
self.sock.write(pkt, i + 1)
self._send_str(topic)
if qos > 0:
self.pid += 1
pid = self.pid
struct.pack_into("!H", pkt, 0, pid)
self.sock.write(pkt, 2)
self.sock.write(msg)
if qos == 1:
while 1:
op = self.wait_msg()
if op == 0x40:
sz = self.sock.read(1)
assert sz == b"\x02"
rcv_pid = self.sock.read(2)
rcv_pid = rcv_pid[0] << 8 | rcv_pid[1]
if pid == rcv_pid:
return
elif qos == 2:
assert 0
def subscribe(self, topic, qos=0):
assert self.cb is not None, "Subscribe callback is not set"
pkt = bytearray(b"\x82\0\0\0")
self.pid += 1
struct.pack_into("!BH", pkt, 1, 2 + 2 + len(topic) + 1, self.pid)
#print(hex(len(pkt)), hexlify(pkt, ":"))
self.sock.write(pkt)
self._send_str(topic)
self.sock.write(qos.to_bytes(1, "little"))
while 1:
op = self.wait_msg()
if op == 0x90:
resp = self.sock.read(4)
#print(resp)
assert resp[1] == pkt[2] and resp[2] == pkt[3]
if resp[3] == 0x80:
raise MQTTException(resp[3])
return
# Wait for a single incoming MQTT message and process it.
# Subscribed messages are delivered to a callback previously
# set by .set_callback() method. Other (internal) MQTT
# messages processed internally.
def wait_msg(self):
res = self.sock.read(1)
self.sock.setblocking(True)
if res is None:
return None
if res == b"":
raise OSError(-1)
if res == b"\xd0": # PINGRESP
sz = self.sock.read(1)[0]
assert sz == 0
return None
op = res[0]
if op & 0xf0 != 0x30:
return op
sz = self._recv_len()
topic_len = self.sock.read(2)
topic_len = (topic_len[0] << 8) | topic_len[1]
topic = self.sock.read(topic_len)
sz -= topic_len + 2
if op & 6:
pid = self.sock.read(2)
pid = pid[0] << 8 | pid[1]
sz -= 2
msg = self.sock.read(sz)
self.cb(topic, msg)
if op & 6 == 2:
pkt = bytearray(b"\x40\x02\0\0")
struct.pack_into("!H", pkt, 2, pid)
self.sock.write(pkt)
elif op & 6 == 4:
assert 0
def check_msg(self):
self.sock.setblocking(False)
return self.wait_msg()3. buat file bernama main.py
import machine
from wifi import Wifi
Wifi().connect("Suko","sooko9999")
from mqtt import MQTTClient
import ubinascii
from machine import Pin
class Iot(object):
client_id = ubinascii.hexlify(machine.unique_id())
client=None
def __init__(self,*args,**kwargs):
super(Iot,self).__init__(*args,**kwargs)
try:
print('mqtt running')
self.client=MQTTClient(self.client_id,"mqtt.eclipse.org",keepalive=0)
self.client.connect()
self.client.set_callback(self.on_message)
self.client.subscribe(b"sooko/lampu")
while True:
self.client.wait_msg()
except:
print('mqtt stoped')
Wifi().disconnect()
machine.reset()
def on_message(self,topic,msg):
print(topic,msg)
if msg==b"on":
self.grenn_on()
self.client.publish(b"loger",b"saya hidup")
elif msg==b"off":
self.grenn_off()
self.client.publish(b"loger", b"saya mati")
def grenn_on(self):
Pin(2,Pin.OUT).value(0)
def grenn_off(self):
Pin(2,Pin.OUT).value(1)
Iot()Download progam ke board
Setelelah ketiga file diatas berhasil dibuat.saat nya kita medownload progam tadi ke dalam board esp8266 menggunakan adafruit-ampy
Menggunakan adafruit-ampy tulis perintah berikut pada terminal untuk mendownload file satu persatu
- ampy –port <port com anda> put wifi.py
- ampy –port <port com anda> put mqtt.py
- ampy –port <port com anda> put main.py