Firmware for Airgradient ONE v9

based on https://github.com/airgradienthq/arduino

Changes

• API URL hw.airgradient.com set to airgradient.internal
• sending measurements via HTTP disabled
• inital ping to server on startup is disabled
• HTTP config endpoint is only called once on startup, not on a schedule
• hardware watchdog reset after sending mqtt message
• RGB strip shows gradual changes in CO2 value by calculating hue dynamically
• added PlatformIO configuration

Using local config endpoint

A json object is expected at the webserver config endpoint. Here is an example configuration using Caddy:

http://airgradient.internal {
  respond /sensors/airgradient:SERIALNO/one/config `{"country": "DE", "pmStandard": "ugm3", "co2CalibrationRequested": false, "ledBarMode": "co2", "model": "onev9", "mqttBrokerUrl": "mqtt://user:password@mqtt-server:1883", "abcDays": -1, "ledBarTestRequested": false}` 200
  respond "request blocked" 403
}

replace SERIALNO with the serial number of your device

Updating

Use the update.sh script which downloads the newest version from the Airgradient GitHub repo and automatically pastes the aforementioned changes into the file

References

• Build instructions: https://www.airgradient.com/open-airgradient/instructions/pro-v9/
• Installation instructions: https://www.airgradient.com/blog/install-arduino-c3-mini/
• Source code: https://github.com/airgradienthq/arduino
• Detailed installation instructions with solution to compilation errors (patching the PMS Library is not needed anymore): https://www.cnx-software.com/2023/11/29/airgradient-one-kit-review-an-open-source-indoor-air-quality-monitor/
• Patched PMS Library code: https://www.airgradient.com/blog/patching-pms-library-for-plantower-pms5003t/