W_B: Write binary

BA-Object reference

Structure

[BaObjRef] defines a bound connection between XFB and BACnet object. The binding occurs automatically.

Manual configuration attempts are not necessary and can result in system errors.

DeviceId

Device identifier

Double word (default value: 16#3FFFFF)

[DeviceId] comprises object type and object instance in a single identifier.

It is used to identify device object: local or remote. Local device object could also be identified by value 16#3FFFFF.

ObjectId

Object identifier

Double word (default value: 16#3FFFFF)

[ObjectId] comprises object type and object instance in a single identifier.

It is used to identify object within a device.

ItemId

Item identifier

Integer (default value: -1)

[ItemId] represents an item index in the functional view node object, which references the BACnet object.

[ObjectId] and [ItemId] together define an indirect access reference to the BACnet object.

Value -1 indicates that direct binding is used.

Value

Boolean (default value: False)

A virtual value calculated and assigned by the control program to update present value.

[Val] is used to update the Tracking value property, after which the BACnet object internally updates Present value with the written Tracking value.

[Val] will be written if [EnWrit] is True and any of the following:

• [Val] changes.
• [SetValid] changes.
• [RptWrit] is True.

Set valid value indication

Boolean (default value: True)

A value calculated and assigned by the control program that indicates whether [Val] is reliable.

[SetValid] maps to an error code that updates reliability if [EnWrit] is True and any of the following:

• [SetValid] changes.
• [Val] changes.
• [RptWrit] is True.

1 (True)

Reliability error code 0 (no fault)

0 (False)

Reliability error code 7 (unreliable - other)

Repeat write

Boolean (default value: False)

[RptWrit] forces a write of inputs [Val] and [SetValid] to the data point. The write operation is repeated with each program cycle for as long as [RptWrit] is True.

[RptWrit] will typically be calculated and set by the control program.

Note:
[RptWrit] must not be forced permanently to True by connecting to a block output that is always True. Doing so will cause a high level of communication traffic.

1 (True)

If [EnWrit] is True, [Val] and [SetValid] are written to the data point with each program cycle for as long as [RptWrit] is True.

0 (False)
default

No action

Present value

Boolean (default value: False)

The value of the present value property from the referenced BACnet object.

[PrVal] will deliver the last valid value if [Valid] = False.

Valid

Boolean (default value: False)

An indication of whether output pin [PrVal] is reliable.

1 (True)

[PrVal] is reliable.

• XFB can access the BACnet object.

AND

• Fault flag in state flag property = 0 (no fault)
  (Reliability = 0 (no error) or Reliability was not detected).

0 (False)

[PrVal] is not reliable.

• XFB cannot access the BACnet object.

OR

• Fault flag in state flag property = 1 (fault)
  (Reliability ≠ 0).

Error code indication

Integer (default value: 20)

The status of the last performance of the XFB read operation.

= 0

No error.

> 0

Error, see XFB error codes.

Error while writing

Integer (default value: 20)

The status of the last execution of the XFB write operation.

= 0

No error.

> 0

Error, see XFB error codes.