Time Pattern Value
A Time Pattern Value object holds a time of day in which any field can be a wildcard. With the hour left as a wildcard, 00:30 means half past every hour; with the minute left as one, 07:xx means any time in the seven o’clock hour. Use it where a plain time would be too exact, such as in the rules of a schedule or a trigger.
Typical uses
Section titled “Typical uses”- Every quarter hour: minute 0, 15, 30, 45 of any hour
- Run a task in the first minute of every hour
- Time window rule for a scheduled action
- Match any time within a chosen hour
- A named recurring time clients can read
Key properties
Section titled “Key properties”| Property | What it holds |
|---|---|
| Present_Value | The time pattern. Each of hour, minute, second and hundredths is either a number or a wildcard that matches anything. |
| Priority_Array | Optional. Present only when the value is commandable; sixteen priority slots. |
| Relinquish_Default | Optional. The pattern used when every priority slot is empty. |
| Out_Of_Service | When true, Present_Value stops following its source and a client can write it for testing. |
How it behaves
Section titled “How it behaves”The object is not commandable unless you give it a priority array. The standard applies no event algorithm to it, so it reports faults only. COV notifications go out on any change to Present_Value or Status_Flags.
With the CAS BACnet Stack
Section titled “With the CAS BACnet Stack”Enable it with the STACK_OPTION_OBJECT_TYPE_TIME_PATTERN_VALUE build option and add each object with BACnetStack_AddObject. Serve Present_Value with the callback you register with BACnetStack_RegisterCallbackGetPropertyTime and, if clients may write it, the BACnetStack_RegisterCallbackSetPropertyTime callback. The object becomes commandable once you enable both PriorityArray and RelinquishDefault. The standard applies no event algorithm to this type and the stack serves no event state for it, so there is nothing to arm: BACnetStack_SetAlarmsAndEventsForObjectEnabled accepts the object but changes nothing a client can see. Call BACnetStack_UpdateValue whenever the value you serve changes, so COV, trend logs and alarms see it.
Related object types
Section titled “Related object types”Time Value, Date Pattern Value, DateTime Pattern Value
Properties
Section titled “Properties”The properties ASHRAE 135-2024 clause 12.47 defines for this object type.
How to read the table:
- Conformance is what the standard asks of every object of this type: R is required, W is required and writable by a client, O is optional. A digit after the letter marks a condition in the standard that decides when the property is present or writable, such as support for intrinsic reporting.
- Present by default: yes means the stack presents the property as soon as you add the object; no means it
is optional and you turn it on with
BACnetStack_SetPropertyEnabled. This is the stack’s starting setup, so it can differ from the conformance code. - Writable is whether a client can write the property by default. Change it with
BACnetStack_SetPropertyWritable. - not in profile means the stack does not offer this property for this object type.
- Value when your callback does not answer: “Held by the stack” means the stack stores and serves the value itself and does not ask your callbacks. Otherwise it is the value the stack answers when your callback declines or is not registered.
| Property | Datatype | Conformance | Present by default | Writable | Value when your callback does not answer |
|---|---|---|---|---|---|
| Object_Identifier | BACnetObjectIdentifier | R | yes | no | Held by the stack. |
| Object_Name | CharacterString | R | yes | no | "Object <type>,<instance>", such as "Object 0,1" for Analog Input 1. |
| Object_Type | BACnetObjectType | R | yes | no | Held by the stack. |
| Description | CharacterString | O | no | no | "" |
| Present_Value | TimePattern | R1 | yes | no (yes while Out_Of_Service is true) | No default: value-not-initialized. Once Priority_Array and Relinquish_Default are enabled, built by the stack from the priority array your callbacks serve. |
| Status_Flags | BACnetStatusFlags | R | yes | no | Built by the stack from your callbacks. |
| Event_State | BACnetEventState | O | no | no | 0 |
| Reliability | BACnetReliability | O | no | no (yes while Out_Of_Service is true) | 0 |
| Out_Of_Service | Boolean | O | no | no | false |
| Priority_Array | BACnetARRAY[16] of BACnetOptionalTimePattern | O2 | no | no | Built by the stack from your callbacks. |
| Relinquish_Default | Time | O2 | no | no | No default: value-not-initialized until a callback or a client write supplies one. |
| Reliability_Evaluation_Inhibit | Boolean | O3 | no | no | false |
| Property_List | BACnetARRAY[N] of BACnetPropertyIdentifier | R | yes | no | Held by the stack. |
| Event_Detection_Enable | Boolean | O4,5 | no | no | false |
| Notification_Class | Unsigned | O4,5 | no | no | 0 |
| Event_Enable | BACnetEventTransitionBits | O4,5 | no | no | An empty bit string. |
| Acked_Transitions | BACnetEventTransitionBits | O4,5 | no | no | An empty bit string. |
| Notify_Type | BACnetNotifyType | O4,5 | no | no | 0 |
| Event_Time_Stamps | BACnetARRAY[3] of BACnetTimeStamp | O4,5 | no | no | No default: the read fails. |
| Event_Message_Texts | BACnetARRAY[3] of CharacterString | O5 | no | no | "" |
| Event_Message_Texts_Config | BACnetARRAY[3] of CharacterString | O5 | no | no | "" |
| Current_Command_Priority | BACnetOptionalUnsigned | O2 | no | no | Built by the stack from your callbacks. |
| Value_Source | BACnetValueSource | O6,8,10 | no | no | No default: the read fails. |
| Value_Source_Array | BACnetARRAY[16] of BACnetValueSource | O7,9 | no | no | No default: the read fails. |
| Last_Command_Time | BACnetTimeStamp | O7,9 | no | no | No default: the read fails. |
| Command_Time_Array | BACnetARRAY[16] of BACnetTimeStamp | O9 | no | no | No default: the read fails. |
| Audit_Level | BACnetAuditLevel | O11 | not in profile | not in profile | No default: the read fails. |
| Auditable_Operations | BACnetAuditOperationFlags | O11 | not in profile | not in profile | No default: the read fails. |
| Audit_Priority_Filter | BACnetOptionalPriorityFilter | O11 | not in profile | not in profile | No default: the read fails. |
| Tags | BACnetARRAY[N] of BACnetNameValue | O | no | no | No default: the read fails. |
| Profile_Location | CharacterString | O | no | no | "" |
| Profile_Name | CharacterString | O | no | no | "" |