Hi,
I have managed to get this working using MQTT, After reading quite a bit of documentation and the sites that you provided I'm 99% happy with the results.
This is what I did to get it working.
- Install mosquitto on my Thingworx server.
- Install the TW_Download_MQ Telemetry Transport (MQTT) from the market place onto my Thingworx
- For the Raspberry PI I used this site as a Guide ( https://core-electronics.com.au/tutorials/getting-started-with-home-automation-using-mqtt.html )
- To see if anything was happening I used MQTTlens which helped alot.
- On the PI I ran this script to send data to the MQTT Broker.
# MQTT Publish Demo
# Publish two messages, to two different topics
import paho.mqtt.publish as publish
#client.connect("192.168.2.207", 1883, 60)
#publish.single("CoreElectronics/test", "Hello", hostname="test.mosquitto.org")
publish.single("Thingworx/Name", "Hello", hostname="192.168.2.207")
#publish.single("CoreElectronics/topic", "World!", hostname="test.mosquitto.org")
publish.single("Thingworx/Topic", "World!", hostname="192.168.2.207")
print("Done")
- This is useful but not nessary as the idea is to have that information sent from thingworx
- The Client on the other hand is the important part for the PI. (I will need to tweak this but in general its working)
- The client runs as a script and listens to the topics. In my case the topics are Thingworx/ Name , Topic and Color.
- When the messages comes in the sense hat shows the message.
# MQTT Client demo
# Continuously monitor two different MQTT topics for data,
# check if the received data matches two predefined 'commands'
import paho.mqtt.client as mqtt
from sense_hat import SenseHat
sense = SenseHat()
# The callback for when the client receives a CONNACK response from the server.
def on_connect(client, userdata, flags, rc):
print("Connected with result code "+str(rc))
# Subscribing in on_connect() - if we lose the connection and
# reconnect then subscriptions will be renewed.
#client.subscribe("CoreElectronics/test")
client.subscribe("Thingworx/Name")
cleint.subscribe("Thingworx/Topic")
client.subscribe("Thingworx/Color")
#client.subscribe("CoreElectronics/topic")
# The callback for when a PUBLISH message is received from the server.
def on_message(client, userdata, msg):
print(msg.topic+" "+str(msg.payload))
#sense.show_message(msg.payload) # placing this here will print all the messages on the sence hat screen which is not optimal
if msg.payload == "Hello":
print("Received message #1, do something")
# Do something
if msg.payload == "World!":
print("Received message #2, do something else")
# Do something else
if msg.payload =="red":
print("Recieved a message from the PI to ")
# Do Something here like print a message to the the sense hat screen
sense.show_message(msg.payload) # This is a better place to do something like set the screen to red/blue/clear etc.
# Create an MQTT client and attach our routines to it.
client = mqtt.Client()
client.on_connect = on_connect
client.on_message = on_message
#client.connect("test.mosquitto.org", 1883, 60)
client.connect("192.168.2.207", 1883, 60)
# Process network traffic and dispatch callbacks. This will also handle
# reconnecting. Check the documentation at
# https://github.com/eclipse/paho.mqtt.python
# for information on how to use other loop*() functions
client.loop_forever()
Now that that was working I can connect my thingworx server and test the theory.
Create a new thing and use the MQTT template.
Create 3 properties called Name Topic and Screen_Color
In configuration the Name must be the same as the property and the value that you want it to be set to must be the full path to the topic.
For example Name: Screen_Color Topic Thingworx/Color
By setting the properties here I can update the PI!
And the Message shows on the Sensehat!
