SWEC 2016 IoT Workshop

Step 1: Connecting

About the Photon

https://www.particle.io/

With Particle's Photon series of hardware development kits, connectivity modules, and accessories, you can quickly and easily build Wi-Fi connected products. The Photon architecture sits at the heart of a huge range of IoT products, from smart home products to commercial sensor networks.

The Photons can be connected to a power shield for mobile usage. The correct way to connect them:

Particle Cloud

We have created Particle accounts for up to five groups in the SWEC IoT workshop. When x is your group number (1..5), your account on Particle (https://login.particle.io/login) is:

iot.swecx@gmail.com

The password for all accounts is

MethodPark19a

Two Particle Photons are connected with each account: SWEC-x (the one with the breadboard) and SWEC-xa.

Step 2: First LED

About I/Os

https://en.wikipedia.org/wiki/General-purpose_input/output

Install the free 'Particle' app

Toggling the on-board LED

Connect one (or both) of your photons to the power supply
Connect to your photon with the Particle App
The photon currently runs the tinker firmware, which allows you to access the individual pins with the Particle App
In the Paticle App: Set port 'D7' to 'digitalWrite' and then set it to 'HIGH'
This port is connected to the on-board LED

Step 3: One more LED

Adding the external LED

The photon package contains
a LED
a resistor
a small scetch on how to connect the LED
Never connect the LED without a resistor or it will get damaged
Test the LED using the Particle App

Write software to get the LED blinking

Web IDE: https://build.particle.io/build
Detailed description: https://docs.particle.io/guide/getting-started/examples/photon/#blink-an-leds

Step 4: A Photoresistor

What is a photoresistor?

A resistor that changes it's resistance depending on how much light hits its surface

Adding the photoresistor

The photon package also contains
a photoresistor
a second resistor
a small scetch on how to connect the photoresistor
Test the photoresistor using the Particle App

Step 5: Publishing to the photon cloud

Send your brightness into the photon cloud and read it with the Photon App
Documentation for clound-functions: https://docs.particle.io/reference/firmware/photon/#cloud-functions

Step 6: A temperature sensor

Add the temperature sensor and publish the temperture to the photon cloud
Documentation: http://diotlabs.daraghbyrne.me/3-working-with-sensors/DS18B20/

Step 7: Connecting your photons

Your Task

Use the particle cloud to communicate with your photons
One photon publishes some sensor data
e.g. temperature or brightness
The other photon listens to this data and reacts to it
e.g. enable the on-board LED when brightness drops

Publish/Subscribe in the photon cloud

See reference documentation: https://docs.particle.io/reference/firmware/p<hoton/#cloud-functions

Step 8: Getting connected with MQTT

What is MQTT?

https://en.wikipedia.org/wiki/MQTT:

MQTT is an ISO standard publish-subscribe-based "lightweight" messaging protocol for use on top of the TCP/IP protocol. It is designed for connections with remote locations where a "small code footprint" is required or the network bandwidth is limited. The publish-subscribe messaging pattern requires a message broker. The broker is responsible for distributing messages to interested clients based on the topic of a message.

Yor Task

Create new App and add the MQTT library
Connect to the MQTT server and send a hello-world message when connected
Subscribe to the buzzer and do something when the buzzer is pressed
e.g. toggle a LED

MQTT Server

Hostname: openhabpi
Port: 1883
No authentication
Suggested client name: The name of your photon

MQTT library

Callback to receive subscribed messages:

void mqtt_callback(char* topic, byte* payload, unsigned int length);

Constructor:

MQTT::MQTT(String server_url, int port, callback* callback_ptr);

Connecting to the server:

MQTT::connect(String client_name);

Connecting with credentials:

MQTT::connect(String client_name, String user_name, String password);

Publishing/Sending a message:

MQTT::publish(String topic, String payload);

Subscribing to a topic, that will then be received via the callback:

MQTT::subscribe(String topic);

Buzzer

Topic: buzzer
Payload: empty
The message is sent each time the buzzer is pressed

Step 9: Publish your temperture and brightness

Send your temperature and brightness to the MQTT server
topic: "swec/temperature", payload: "x/t"
topic: "swec/brightness", payload: "x/b"
x: your group id (1-5)
t: temperature in celsius, e.g. 30.0
b: brightness, 0=absolute dark, 1023=very bright
intervall: 200ms

Step 10: croud control

Control the Hue with your photons

methodpark/swec-iot