> For the complete documentation index, see [llms.txt](https://docs.cybus.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.cybus.io/connectors/shop-floor-connectors/bacnet/bacnetendpoint.md).

# BACnet Endpoint Properties

## `objectType` (string, enum, required)

Identifier of the BACnet object type of this endpoint

This element must be one of the following enum values:

* `analog-input`
* `analog-output`
* `analog-value`
* `binary-input`
* `binary-output`
* `binary-value`
* `multi-state-input`
* `multi-state-output`
* `multi-state-value`
* `accumulator`
* `pulse-converter`
* `trend-log`
* `trend-log-multiple`
* `event-log`
* `integer-value`
* `large-analog-value`
* `positive-integer-value`
* `characterstring-value`
* `octetstring-value`
* `bitstring-value`
* `date-value`
* `time-value`
* `datetime-value`
* `date-pattern-value`
* `time-pattern-value`
* `datetime-pattern-value`
* `calendar`
* `schedule`
* `lighting-output`
* `binary-lighting-output`
* `channel`
* `life-safety-point`
* `life-safety-zone`
* `access-point`
* `access-zone`
* `access-door`
* `access-user`
* `access-rights`
* `access-credential`
* `credential-data-input`
* `lift`
* `escalator`
* `elevator-group`
* `staging`
* `group`
* `global-group`
* `structured-view`
* `event-enrollment`
* `alert-enrollment`
* `notification-class`
* `notification-forwarder`
* `command`
* `loop`
* `program`
* `averaging`
* `load-control`
* `network-port`
* `network-security`
* `device`
* `file`

Example: `"analog-input"`

## `objectInstance` (integer, required)

Integer number to describe the concrete object instance that should be accessed. ASHRAE 135 §20.2.14 bounds the instance to 22 bits (0-4194303).

Example: `1`

Additional restrictions:

* Maximum: `4194303`

## `property` (string, required)

BACnet property name (e.g., 'present-value', 'status-flags', 'units', 'priority-array', 'object-name'). 'present-value' is the most common for I/O objects.

Example: `"present-value"`

## `interval` (integer)

Polling interval in milliseconds. Default 1000. Set this conservatively for legacy controllers (Trend IQ4, Andover) at 5000-15000 ms to avoid TSM exhaustion on the shared process iid pool.

Default: `1000`

Example: `1000`

Additional restrictions:

* Minimum: `100`

## `cronExpression` (string)

The Cron expression used to poll the endpoint. (For examples, see: <https://github.com/node-cron/node-cron>)

Examples: `"1,2,4,5 * * * *"`, `"1-5 * * * *"`, `"*/2 * * * *"`, `"* * * January,September Sunday"`

## `priority` (integer)

Write priority per ASHRAE 135 §19.2 / Table 19-1 (1-16). 1 = highest (life-safety), 6 = critical equipment control, 8 = manual operator override, 16 = lowest / relinquish to default. Default 15; set explicitly for any commandable output. Writing NULL at any priority relinquishes that level. Operators competing at the same priority overwrite each other silently.

Example: `16`

Additional restrictions:

* Minimum: `1`
* Maximum: `16`

## `propertyTag` (integer)

Application tag (ASHRAE 135 §20.2.1) — forces the data type for writes when the device's expectation differs from JS-side type inference. Standard tags 0-12: 0=NULL, 1=BOOLEAN, 2=UNSIGNED\_INT, 3=SIGNED\_INT, 4=REAL, 5=DOUBLE, 6=OCTET\_STRING, 7=CHARACTER\_STRING, 8=BIT\_STRING, 9=ENUMERATED, 10=DATE, 11=TIME, 12=OBJECT\_IDENTIFIER. Tags 13-15 are reserved by ASHRAE. Omit for reads.

Example: `4`

Additional restrictions:

* Maximum: `12`


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