> For the complete documentation index, see [llms.txt](https://docs.simplephysx.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.simplephysx.com/spx-development-guide/spx-core/communications/bacnet.md).

# BACnet

**YAML key:** `bacnet`

Expose BACnet/IP objects backed by SPX attributes (read/write mappings live under `objects.*.properties`).

## Minimal configuration

```yaml
attributes:
  room_temperature: 22.0
  fan_enable: 0

communication:
  - bacnet:
      host: 0.0.0.0
      port: 47808
      device:
        instance_id: 2001
        vendor_id: 999
        name: "SPX BACnet Simulator"
      objects:
        room_temp:
          type: analogInput
          instance: 2
          properties:
            presentValue:
              read: "#attr(room_temperature)"
            units: degreesCelsius
        fan_command:
          type: binaryOutput
          instance: 10
          priority: 8
          properties:
            presentValue:
              read: "#attr(fan_enable)"
              write: "#attr(fan_enable)"
              states:
                0: inactive
                1: active
            relinquishDefault: 0
```

## Notes

* Dependency: requires `bacpypes3` in the SPX Server environment.
* The full schema supports additional BACnet features (device metadata, schedules, alarms). See spx-examples for richer models.

## References

* Example models (spx-examples):
  * [`hvac_flexit_nordic__bacnet.yaml`](https://github.com/HammerHeads-Engineers/spx-examples/blob/develop/library/domains/building/controller/generic/hvac_flexit_nordic__bacnet.yaml)
  * [`fire_alarm_panel__bacnet.yaml`](https://github.com/HammerHeads-Engineers/spx-examples/blob/develop/library/domains/building/panel/generic/fire_alarm_panel__bacnet.yaml)

## Next steps on simplephysx.com

Explore the BACnet simulator workflow:

* [BACnet Simulator](https://www.simplephysx.com/bacnet-simulator)