IoT Engineering

Hands-on of lesson 3

For slides and example code, see lesson 3

Note: Do not work on this repository right away.
Create your personal copy by clicking this GitHub Classroom link.

a) ESP8266 Wi-Fi, 15'

• Build and run the previous Wi-Fi related examples.
• Use the .ino link on each page to find the source.
• The examples are in the course repository.
• Make sure to use the ESP8266 board

b) ESP8266 NTP clients, 15'

• Build, run and compare the following NTP clients:
• The Web-based time client and built-in NTP client.
• Arduino > Examples > ESP8266WiFi > NTPClient.
• Bonus: Read the code of this low memory version.

c) ESP8266 TLS clients, 15'

• Build, run and compare the following TLS clients:
• Secure Wi-Fi client, with fingerprint, with CA check.
• Locate/download the CA certificate in your browser.
• Locate the SHA-1 fingerprint of the host certificate.
• Bonus: Try to change the host to another Website.

d) Dweet.io, 15'

• Dweet.io works without an account, data is public.
• Use your ESP8266 MAC address as THING_NAME.
• On the ESP8266, read the analog pin A0, then POST
  its value to /dweet/for/THING_NAME?a0=value
• Use cURL or your browser to read stored data from
  https://dweet.io/get/dweets/for/THING_NAME

e) ThingSpeak, 15'

• Get an account to create channels and get API keys.
• Add the Arduino library with Sketch > Include
• Library > Manage Libraries... > ThingSpeak > Install
• Try the example code File > Examples > ThingSpeak > ESP8266 > WriteMultipleFields.ino
• Make sure values arrive in your ThingSpeak channel.

f) Temperature sensor, 15'

• Design a connected temperature sensor as specified:
• Gets current time and date in ISO 8601 UTC format.
• Gets temperature & humidity from a DHT11 sensor.
• Connects to api.thingspeak.com port 443 with TLS.
  (And robustly reconnects, if disconnected.)
• Posts sensor values, timestamp every 30 seconds.

g) Homework, max. 3h

• Implement or finish the temp. sensor you designed.
• Post the IoT platform data feed URL to the Slack.
• Commit the Arduino code to the hands-on repo.
• Measure the temperature for at least 24 hours.

Submitting results

• Commit and push local changes to your repository.
• Want a review? Create an issue, mention me (@tamberg).

Tools

Git

On your computer

• In the hands-on repository fork for your class, in README.md, click the GitHub Classroom link.
• Once you accept the assessment, you get a personal, private repository URL for your USER_NAME:

  http://github.com/fhnw-iot-CLASS/fhnw-iot-work-03-USER_NAME

On your computer or Raspberry Pi

• Clone the repository

  $ cd ~
  $ git clone REPO_URL

• Add a file

  $ git add FILE

• Commit changes

  $ git commit FILE -m "Fixed all bugs"

• Push changes

  $ git push

Wiki

• IoT Engineering Wiki

Support

• IoT Engineering Slack