from machine import Pin
from umqtt.simple import MQTTClient
import ujson
import network
import utime as time
import dht
# Device Setup
DEVICE_ID = "wokwi001"
# WiFi Setup
WIFI_SSID = "Wokwi-GUEST"
WIFI_PASSWORD = ""
# MQTT Setup
MQTT_BROKER = "broker.mqttdashboard.com"
MQTT_CLIENT = DEVICE_ID
MQTT_TELEMETRY_TOPIC = "iot/telemetry"
MQTT_CONTROL_TOPIC = "iot/control"
# DHT Sensor Setup
DHT_PIN = Pin(15)
# LED/LAMP Setup
RED_LED = Pin(12, Pin.OUT)
BLUE_LED = Pin(13, Pin.OUT)
FLASH_LED = Pin(2, Pin.OUT)
RED_LED.on()
BLUE_LED.on()
# Methods
def did_recieve_callback(topic, message):
print('\n\nData Recieved! \ntopic = {0}, message = {1}'.format(topic, message))
# device_id/lamp/color/state
# device_id/lamp/state
# lamp/state
if topic == MQTT_CONTROL_TOPIC.encode():
if message == ('{0}/lamp/red/on'.format(DEVICE_ID)).encode():
RED_LED.on()
elif message == ('{0}/lamp/red/off'.format(DEVICE_ID)).encode():
RED_LED.off()
elif message == ('{0}/lamp/blue/on'.format(DEVICE_ID)).encode():
BLUE_LED.on()
elif message == ('{0}/lamp/blue/off'.format(DEVICE_ID)).encode():
BLUE_LED.off()
elif message == ('{0}/lamp/on'.format(DEVICE_ID)).encode() or message == b'lamp/on':
RED_LED.on()
BLUE_LED.on()
elif message == ('{0}/lamp/off'.format(DEVICE_ID)).encode() or message == b'lamp/off':
RED_LED.off()
BLUE_LED.off()
elif message == ('{0}/status'.format(DEVICE_ID)).encode() or message == ('status').encode():
global telemetry_data_old
mqtt_client_publish(MQTT_TELEMETRY_TOPIC, telemetry_data_old)
else:
return
send_led_status()
def mqtt_connect():
print("Connecting to MQTT broker ...", end="")
mqtt_client = MQTTClient(MQTT_CLIENT, MQTT_BROKER, user="", password="")
mqtt_client.set_callback(did_recieve_callback)
mqtt_client.connect()
print("Connected.")
mqtt_client.subscribe(MQTT_CONTROL_TOPIC)
return mqtt_client
def create_json_data(temperature, humidity):
data = ujson.dumps({
"device_id": DEVICE_ID,
"temp": temperature,
"humidity": humidity,
"type": "sensor"
})
return data
def mqtt_client_publish(topic, data):
print("\nUpdating MQTT Broker...")
mqtt_client.publish(topic, data)
print(data)
def send_led_status():
data = ujson.dumps({
"device_id": DEVICE_ID,
"red_led": "ON" if RED_LED.value() == 1 else "OFF",
"blue_led": "ON" if BLUE_LED.value() == 1 else "OFF",
"type": "lamp"
})
mqtt_client_publish(MQTT_TELEMETRY_TOPIC, data)
# Application Logic
# Connect to WiFi
wifi_client = network.WLAN(network.STA_IF)
wifi_client.active(True)
print("Connecting device to WiFi")
wifi_client.connect(WIFI_SSID, WIFI_PASSWORD)
# Wait until WiFi is Connected
while not wifi_client.isconnected():
print("Connecting")
time.sleep(0.1)
print("WiFi Connected!")
print(wifi_client.ifconfig())
# Connect to MQTT
mqtt_client = mqtt_connect()
RED_LED.off()
BLUE_LED.off()
mqtt_client_publish(MQTT_CONTROL_TOPIC, 'lamp/off')
dht_sensor = dht.DHT22(DHT_PIN)
telemetry_data_old = ""
while True:
mqtt_client.check_msg()
print(". ", end="")
FLASH_LED.on()
try:
dht_sensor.measure()
except:
pass
time.sleep(0.2)
FLASH_LED.off()
telemetry_data_new = create_json_data(dht_sensor.temperature(), dht_sensor.humidity())
if telemetry_data_new != telemetry_data_old:
mqtt_client_publish(MQTT_TELEMETRY_TOPIC, telemetry_data_new)
telemetry_data_old = telemetry_data_new
time.sleep(0.1)