ThingSpeak

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Hello, I was working on a project to contol an LED connected to the Pi 4 using the subscribe feature in ThingSpeak MQTT. While I was able to publish data to ThingSpeak MQTT using the Pi 4 without any issues, I faced trouble while trying to subscribe to a channel in ThingSpeak MQTT to read data from a field to control an LED connected to the Pi. Initially, I had interfaced both the LED and a BMP180 sensor to the same Pi and wanted to publish data from the BMP180 to a ThingSpeak channel and subscribe to the channel to control my LED based on the temperature values (I ran seperate scripts on the Pi 4 for the Publish and subscribe simuntaneously). Though the publish part worked, the subscribe part did not. I thought this was because I was using the same device (the Pi) to publish and subscribe to the channel. So later, I installed the MQTT.fx app in my PC and used it to publish values to a new private ThingSpeak channel. I then used the Pi to subscribe to the same channel, receive values and control the LED that was interfaced to it. This did not work either. I am unable to receive messages from the ThingSpeak MQTT channel when I subscribe to it from the Pi 4. I double checked the Channel ID and API keys were correct. I'm using the Paho MQTT library for publish and subscribe to ThingSpeak MQTT. I used port 1883. I will share the python code I used to subscribe to the ThingSpeak MQTT channel. I have the following doubts: Please help me resolve the above issue. (highlighted) Is it possible to use the same device to publish and subscribe to ThingSpeak MQTT, as I did in the first case? If yes, how? Code I used to subscribe to the ThingSpeak MQTT channel using the R Pi 4: import paho.mqtt.client as mqttClient import time from gpiozero import LED import random def on_connect(client, userdata, flags, rc): if rc == 0: print("Connected to broker") global Connected Connected = True else: print("Connection failed") def on_message(client, userdata, message): print (message.payload) Connected = False broker_address= "mqtt.thingspeak.com" #Broker address port = 1883 #Broker port user = "pi_led" #Connection username password = "XXXXXXXXXXXXXXXXX"#Connection password - Used my MQTT API key from My Profile client = mqttClient.Client("Python") #create new instance client.username_pw_set(user, password=password)#set username and password client.on_connect= on_connect #attach function to callback client.on_message= on_message #attach function to callback client.connect(broker_address, port=port) #connect to broker client.loop_start() #start the loop while Connected != True:#Wait for connection time.sleep(0.1) channelID = "1304227" READapiKey = "YYYYYYYYYYYYYYYY" topic = "channels/" + channelID + "/subscribe/field/field1/" + READapiKey #led = LED(27) client.subscribe(topic, qos=0) try: while True: time.sleep(1) except KeyboardInterrupt: print ("exiting") client.disconnect() client.loop_stop()