Radio CO₂ Monitor
This guide walks you through the Radio CO₂ Monitor project. At the end, you'll see a dashboard in Node-RED with CO2, temperature, humidity, ambient light and atmospheric pressure.
Block Diagram
Requirements
-
Either the CO₂ Monitor Kit or these individual components:
- 1x Core Module
- 1x Temperature Tag
- 1x Humidity Tag
- 1x Barometer Tag
- 1x CO₂ Module
- 1x Battery Module
- 1x Radio Dongle
-
One of the following:
- HARDWARIO Playground installed (recommended) See Playground Installation for details.
- Raspberry Pi with the HARDWARIO Raspbian distribution See Raspberry Pi Installation for details.
- HARDWARIO Firmware Tool installed See Firmware Flashing Tool for details.
Firmware Upload
You'll upload the firmware to the Core Module with HARDWARIO Playground.
Step 1: Connect the Core Module to your computer with a Micro USB cable
Step 2: Start HARDWARIO Playground
On the Firmware tab, select the hardwario/twr-radio-co2-monitor firmware and upload it to the Core Module. The firmware appears in the list only after you tick Show all.
Flashing Core Module R1 and R2 The older Core Module 1 and the newer Core Module 2 are flashed differently; see Core Module R1 and R2 comparison in the Hardware section.
Step 3: Disconnect the Micro USB cable from the Core Module and the computer
Your firmware is now uploaded.
Hardware Assembly
Watch this short video for a simple step-by-step demonstration:
Playing the video loads it from YouTube (Google).
Step 1: Start with the Battery Module
Check that there are no batteries in the Battery Module.
Step 2: Plug the CO2 Module onto the Battery Module
Step 3: Plug the Core Module onto the CO2 Module
Step 4: Plug the Temperature Tag into a socket on the CO2 Module
Step 5: Plug the Humidity Tag into a socket on the CO2 Module
Step 6: Plug the Barometer Tag into a socket on the CO2 Module
Step 7: Plug the Cover Module onto the Core Module
Playground Setup
If you use the new HARDWARIO Playground, open the Functions tab instead of http://localhost:1880/. Pairing now happens on the Devices tab, and you test communication on the Messages tab.
Step 1: Open Node-RED in your web browser
Step 2: You should see an empty workspace with Flow 1
Step 3: Import the following snippet into the flow (Menu >> Import) and click the Flow 1 tab
[{"id":"2fc604fc.3b6abc","type":"inject","z":"dfc861b.b2a02a","name":"List all gateways","topic":"gateway/all/info/get","payload":"","payloadType":"str","repeat":"","crontab":"","once":false,"x":560,"y":460,"wires":[["a2c10833.24d5d8"]]},{"id":"1e4502b8.2f63fd","type":"inject","z":"dfc861b.b2a02a","name":"Start node pairing","topic":"gateway/usb-dongle/pairing-mode/start","payload":"","payloadType":"str","repeat":"","crontab":"","once":false,"x":570,"y":580,"wires":[["795ff5a7.8e266c"]]},{"id":"3d844ce2.932864","type":"inject","z":"dfc861b.b2a02a","name":"Stop node pairing","topic":"gateway/usb-dongle/pairing-mode/stop","payload":"","payloadType":"str","repeat":"","crontab":"","once":false,"x":560,"y":640,"wires":[["5967c452.c838bc"]]},{"id":"f202b253.2705b","type":"inject","z":"dfc861b.b2a02a","name":"List paired nodes","topic":"gateway/usb-dongle/nodes/get","payload":"","payloadType":"str","repeat":"","crontab":"","once":false,"x":560,"y":520,"wires":[["f0aca138.0b2c3"]]},{"id":"349f02fd.890f6e","type":"inject","z":"dfc861b.b2a02a","name":"Unpair all nodes","topic":"gateway/usb-dongle/nodes/purge","payload":"","payloadType":"str","repeat":"","crontab":"","once":false,"x":560,"y":700,"wires":[["2f1c5bb6.53d6f4"]]},{"id":"cf61d75d.4ad8f8","type":"mqtt in","z":"dfc861b.b2a02a","name":"","topic":"#","qos":"2","broker":"67b8de4a.029d3","x":530,"y":400,"wires":[["a5cb0658.f5d658"]]},{"id":"a5cb0658.f5d658","type":"debug","z":"dfc861b.b2a02a","name":"","active":true,"console":"false","complete":"false","x":790,"y":400,"wires":[]},{"id":"a2c10833.24d5d8","type":"mqtt out","z":"dfc861b.b2a02a","name":"","topic":"","qos":"","retain":"","broker":"717f7c18.ba0a24","x":770,"y":460,"wires":[]},{"id":"f0aca138.0b2c3","type":"mqtt out","z":"dfc861b.b2a02a","name":"","topic":"","qos":"","retain":"","broker":"717f7c18.ba0a24","x":770,"y":520,"wires":[]},{"id":"795ff5a7.8e266c","type":"mqtt out","z":"dfc861b.b2a02a","name":"","topic":"","qos":"","retain":"","broker":"717f7c18.ba0a24","x":770,"y":580,"wires":[]},{"id":"5967c452.c838bc","type":"mqtt out","z":"dfc861b.b2a02a","name":"","topic":"","qos":"","retain":"","broker":"717f7c18.ba0a24","x":770,"y":640,"wires":[]},{"id":"2f1c5bb6.53d6f4","type":"mqtt out","z":"dfc861b.b2a02a","name":"","topic":"","qos":"","retain":"","broker":"717f7c18.ba0a24","x":770,"y":700,"wires":[]},{"id":"67b8de4a.029d3","type":"mqtt-broker","z":"","broker":"127.0.0.1","port":"1883","clientid":"","usetls":false,"compatmode":true,"keepalive":"60","cleansession":true,"willTopic":"","willQos":"0","willPayload":"","birthTopic":"","birthQos":"0","birthPayload":""},{"id":"717f7c18.ba0a24","type":"mqtt-broker","z":"","broker":"127.0.0.1","port":"1883","clientid":"","usetls":false,"compatmode":true,"keepalive":"60","cleansession":true,"willTopic":"","willQos":"0","willPayload":"","birthTopic":"","birthQos":"0","birthPayload":""}]
It looks like this:
The snippet adds buttons for the gateway and radio commands, which are sent over MQTT.
Step 4: Deploy the flow with the Deploy button in the top-right corner
Step 5: Open the debug tab
The debug tab shows all MQTT messages.
Step 6: Click the List all gateways button. The debug tab should show a response like this
You now have working Node-RED, MQTT, HARDWARIO Radio Dongle and HARDWARIO Gateway.
Radio Pairing
In this section, we'll establish a radio link between the Radio Dongle and the Radio CO2 Monitor.
In Node-RED, follow these steps:
Step 1: Click the Start node pairing button
Step 2: Insert the batteries into the Radio CO2 Monitor to send the pairing request (the red LED on the Core Module should also light up for about 2 seconds)
Step 3: Click the Stop node pairing button
You now have a radio link between the node (Radio CO2 Monitor) and the gateway (Radio Dongle).
Communication Test
In Node-RED, follow these steps:
Step 1: Switch to the debug tab on the right
Step 2: Test the device
Breathe on the temperature sensor on the Temperature Tag. The change in temperature triggers a radio transmission.
You should then see messages like these:
Radio communication is now verified.