Changed Callback

Missing functions in IoT

• MQTT broker should be globally reachable
• GUI to easily visualize sensor measurements
• GUI elements to easily control actuators
• GUI should be accessible through a WEB interface
• GUI should be accessible through smart phone app

Cayenne functionality

• MQTT broker is accessible at mqtt.mydevices.com
  
  
• Supplies GUI

Signing up for Cayenne

Sign up at
https://mydevices.com/cayenne/signup

Cayenne Start

Cayenne Doc

You find the documentation at

https://mydevices.com/cayenne/docs/intro

Contains short introductory video clips, information of Cayenne on Raspberry Pi and Arduino but also how to use Cayenne on any device.

Pointers to the Cayenne MQTT Libraries and their API

Installing Cayenne on the Raspberry PI

Installing Cayenne on the Raspberry Pi manually

Register your Controller Single Board Computers

Run Cayenne on the Arduino

Basic Arduino Sketch for the Arduino

Cayenne Credentials

Cayenne network layers

The Cayenne credentials are integrated into the MQTT topic string

Value and units are integrated into the payload string

Cayenne and Python

This falls under “bring your own thing” !

Having a look at the Arduino sketch you can see that it uses the

Arduino Cayenne C++ library.

Cayenne MQTT libraries are available in

• C, C++
• Python
• Java

Cayenne and Micropython

The Python Cayenne Client library depends on the Eclipse Paho MQTT library

Micropython uses its own, stripped down “umqtt” (micro mqtt) library

such that the standard Cayenne Client does not work on Micropython

but …

The Python Cayenne Client is Open Source and can be adapted to umqtt, which is what I did for you.

The adapted Client library uses the same API as the original one,

which means that the example programs work unchanged.

The Cayenne Client

When creating a Cayenne Client Class it

• Initializes its internal variables
• Checks if the OLED display is connected and if yes, initializes it
• The Cayenne Client has has a begin method which
• Connects to WiFi
• Connects to the Cayenne MQTT broker at mqtt.mydevices.com
• Subscribes to commands send by Cayenne
• Displays its internal state on the OLED display

The code to connect to Cayenne

Connecting to Cayenne

The empty Cayenne dashboard