MQTT Workshop for Wemos D1

This is a simple workshop that shows how to use MQTT on the famous Wemos D1.

We will build up a publisher that has a DS18B20 as digital temperature sensor and a receiver that will print the reading on a I²C LCD and switch on the light up the built-in LED if the temperature rises above 30 °C.

You need...

Software

Arduino IDE and the following libraries:

• Arduino core for ESP8266 WiFi chip
• WiFiManager
• PubSubClient for MQTT
• OneWire
• DallasTemperature
• hd44780

Hardware

• 2x Wemos D1
• 1x Maxim DS18B20 (OneWire temperature sensor)
• 1x 4,7 kOhm Resistor
• 1x HD44780 16x02 LCD with Maxim I2C expander
• Breadboards, Jumper Wires

Hardware Setup

Temperature Publisher

Temperature Receiver

Software Setup

1. Install MQTT-Temperature-Publisher on the Wemos with the DC18B20
2. Install MQTT-Temperature-Receiver on the Wemos with the LCD

Resources

• Brief overview over MQTT
• JavaFX based MQTT Client

License

Hell yeah, it's Open Source!