Ajax2MQTT

Note: this project is not affiliated with Ajax Systems.

This app takes messages from ajax security modules and sends them via MQTT, making possible to use Ajax devices in your Homeassistant or Homebridge, save telemetry to InfluxDB, etc.

It doesn’t use Ajax cloud services, doesn’t require internet connection and doesn’t expose any data outside of local network. However it requires special hardware module to interface Ajax wireless protocol (see Required Hardware section below). Setting this module up is trivial and doesn't require special skills or tools.

Supported devices

• uartBridge
• FireProtect
• FireProtect Plus
• MotionProtect (MotionProtect Plus)
• DoorProtect
• SpaceControl
• GlassProtect
• CombiProtect
• LeaksProtect

Required Hardware

• Ajax uartBridge to interface wireless Ajax devices. Costs about $30 (where to buy).
• USB-TTL adapter. Any cheap adapter will work fine, I am using this one. Costs about $1.
• Jumper wires with DuPont female-female connector. Sometimes they are included with usb-ttl adapter. Costs about another $1.
• Plastic enclosure box (optional). Minimal size is 60x60x15mm.

Connecting everything together

• Connect TX pin on bridge to RXD pin on USB-UART adapter
• Connect RX pin on bridge to TXD pin on adapter
• Connect GND pins together
• Connect +5V pins together
• Plug the adapter into USB port on your computer

Some tips:

• Note that transmitting pin on the board (TX) must be connected to receiving pin on the adapter (RX), and not the other way around. These two connections must be crossed: rx -> tx and tx -> rx.
• +5v pin on adapter may also be called VDD.
• TX and RX pins on adapter may have D letter (e.g. TXD and RXD).
• PCB parts without electronic components can be safely removed, so that the whole construction can fit into smaller enclosure. Just break empty parts away by perforated line.

Installation

The recommended installation method is with docker:

$ docker run \
    --name ajax2mqtt \
    --network=host \
    --restart=unless-stopped \
    --device=/dev/your-usb-ttl-adapter-address:/dev/ttyUSB0 \
    -e A2M_HASS_ENABLED=true \
    ingria/ajax2mqtt

The only line you need to change is /dev/your-usb-ttl-adapter-address.

For more complex setup, copy docker-compose.example.yaml to docker-compose.yaml and change environment variables there.

Available variables:

Name	Default value	Description
A2M_SERIAL_PORT	/dev/ttyUSB0 in docker, none in other environments	Path to usb ttl, e.g. /dev/ttyUSB0
A2M_MQTT_ADDRESS	mqtt://127.0.0.1	MQTT broker address
A2M_MQTT_PASSWORD	none	MQTT broker password
A2M_MQTT_USERNAME	none	MQTT broker username
A2M_MQTT_BASE_TOPIC	ajax2mqtt	Base topic to publish device states
A2M_HASS_ENABLED	false	Whether to enable homeassistant integration
A2M_HASS_BASE_TOPIC	homeassistant	Homeassistant base topic (used for last will and birth events)
A2M_LOG_LEVEL	error	Logging level

Integrations

MQTT communication is done with "integration" abstractions. Right now there are two: base and homeassistant, but it is possible to create more. Integration watches for device state and sends messages to MQTT broker. Also it listens for command topics and controls the physical devices.

Base integration

Base integration sends all state changes to ajax2mqtt/ID/state topic and subscribes to the following command topics:

• ajax2mqtt/ID/arm
• ajax2mqtt/ID/disarm
• ajax2mqtt/ID/allow_join
• ajax2mqtt/ID/disallow_join
• ajax2mqtt/ID/unpair device_id
• ajax2mqtt/ID/set_offline_threshold value

You may control the device via these topics or create your own integration based on these topics (e.g. use it in HomeBridge).

Homeassistant integration

This integration adds all your Ajax devices to Home Assistant, thanks to the MQTT discovery. If you don’t need this feature, you can set A2M_HASS_ENABLED config value to false.

License

The Unlicense License. Please see License File for more information.