MQTT on foojay.io - Friends of OpenJDK

Sending sensor data from Raspberry Pi Pico to HiveMQ Cloud

Wed, 05 Jan 2022 11:42:42 +0000

In the previous two posts in this series, we used Java on the Raspberry Pi mini-computer to send sensor data to HiveMQ Cloud, and visualize it on a dashboard.

“Part 1: MQTT on Raspberry Pi, Send Sensor Data to HiveMQ Cloud with Java and Pi4J”
“Part 2: Using MQTT and Raspberry Pi to Visualize Sensor Data on a TilesFX Dashboard”

Now we are going to add some more data to our messaging system with another member of the Raspberry Pi family: the Pico, and add this new data to the JavaFX dashboard from part 2.

MQTT on Raspberry Pi (Part 2)

Wed, 22 Dec 2021 14:58:21 +0000

In the previous post we started our discovery of HiveMQ Cloud with Java on the Raspberry Pi. We created an application to send measurements of various sensors to the HiveMQ Cloud MQTT broker. Using an online websocket client we verified the transition of the messages, and could see the data being published to this online message queue.

Now we will take the next step and subscribe to these topics to receive the data in a dashboard, created with JavaFX.

MQTT on Raspberry Pi: Sensor Data to HiveMQ Cloud with Java and Pi4J

Wed, 15 Dec 2021 09:54:37 +0000

A few years ago I did my first experiments with an MQTT server (Mosquitto) running on a Raspberry Pi to connect an Arduino and Raspberry Pi for the drumbooth of my son . The full process is described in my book “Getting Started with Java on the Raspberry Pi” .

In this series of articles we are going to take a different approach with an online MQTT-compatible service: HiveMQ Cloud . The biggest advantage: no need for an always-on server we must manage ourselves. Yes, Mosquitto runs on a inexpensive Raspberry Pi, but still we require to keep it up-and-running if we use it as the “central hub” to distribute data.