PyCon 2017 IoT Tutorial

The Internet of Things with MicroPython and Friends

Welcome! This repo is mainly here to provide info on how to get setup for the tutorial.

Please note: If your laptop is running a firewall or VPN you will need to disable these for the tutorial to work. We will only be connecting to the wifi network provided by your board, not the internet. Additionally, please make sure to bring a power supply for your laptop - we will be using your laptop to power the hardware and it wont work if you're just running off battery power.

You will be learning to program in micropython using the ESP8266 microcontroller with the WeMos D1 mini development board. Phew! Basically the WeMos is the blue part of the picture below and the ESP is the silver & black part with the weird wave form looking thing (its an antenna). The WeMos gives us some nice extras, like a reset button and a mini USB connection to power and communicate with the board. When I talk about 'the board' I'm referring to the WeMos.

We will be creating a Thing to connect to the Internet that monitors temperature and humidity (the light blue boxy thing beneath the WeMos). There will be blinking LEDs, sensing and communicating, and discussions of basic security for IoT networks. There will also be snacks, I'm told.

Setup Instructions

Here are some instructions to help you get setup for the tutorial. If you run into problems please file an issue / check existing issues or send me a message.

The equipment you will need:

• A computer with wifi and an available USB (3) port. We will use the USB port to power the WeMos. You can also use a USB charging brick instead of a USB port. Please bring the power cable for your laptop as well.

• A web browser. Chrome preferred, Firefox or Windows Edge will also work. The webrepl client behaves a little finicky depending on browser, particularly for copy and paste. These 3 worked well.

Programs to install:

I recommend you create a top-level directory i.e. pycon2017 to keep track of the various repos to clone for this tutorial.

• Clone this repo

• Clone the webrepl client. This is a web interface we will use to program the ESP8266.

cd pycon2017
git clone https://github.com/micropython/webrepl.git

• Install the Mosquitto MQTT broker We will be using Mosquitto to transfer messages using the MQTT protocol.
  • MacOS: brew install mosquitto
  • Windows: Download the Mosquitto Install Files and place in C:\Program Files (x86)\mosquitto
  • Linux: You probably know better than me, check the Mosquitto website

This tutorial has some helpful tips on installing and testing Mosquitto, such as:

1. Start the mosquitto service

• MacOS: brew services start mosquitto
• Windows: cd to the directory where you installed mosquitto and type mosquitto

2. In another terminal/command window, setup a test subscriber. Remember you need to be in the mosquitto directory on Windows for this to work:
   mosquitto_sub -h 127.0.0.1 -i testSub -t debug

3. In another terminal/command window, setup a test publisher and send some messages. You should see these show up in your subscriber terminal
   mosquitto_pub -h 127.0.0.1 -i testPublish -t debug -m 'Hello World'

• Install mqtt-spy for visualization of MQTT messages. Once you have mosquitto setup (see below) you can test out mqtt-spy following the getting started instructions. Version 0.5.3 of mqtt-spy is available in this repo under the "tools" directory

• Time permitting, we will be going over TLS/SSL which involves generating and using certificates and key files. While not mandatory, if you want to generate these files during the tutorial you can the shell scripts under "tools" in this repo for Linux and MacOS and refer to "Linux-MacOS_SSL_Client_Certs_RockingD_Labs.pdf". For Windows, install openssl and follow the instructions in the "Windows Mosquitto SSL Configuration.pdf" under tools from steves-internet-guide. Micropython doesn't presently support SSL certificate verification, so we will just be using this on localhost; it's not a big deal if you can't get this to work.

• Optionally, install the driver for the ESP8266. We won't be using this to connect to the ESP, but if you wanted to have a backup option or are just curious you can add this driver. I've verified that the firmware we are using (see firmware/ in this repo) works with the Mac driver

  • MacOS
  • Windows
  • Linux