BACnetStack_AddCalendarObject

bool BACnetStack_AddCalendarObject(
  const uint32_t deviceInstance,
  const uint32_t calendarObjectInstance);

Adds a Calendar object whose Date_List and Present_Value the stack maintains.

Hands a Calendar object to the stack: from now on the stack holds its Date_List and derives its Present_Value - TRUE if the device’s current Local_Date matches any Date_List entry, FALSE if not (135-2024 cl. 12.9.5). The Date_List starts empty. Populate it with the BACnetStack_AddCalendar*Entry functions below; clients read it with ReadProperty. Present_Value is re-derived every BACnetStack_Tick() and on every read, and a change is reported to COV subscribers.

IMPORTANT: the stack holds no Local_Date. Enable it on the Device object with BACnetStack_SetPropertyEnabled() and serve it, normally from the host clock, with CallbackGetPropertyDate (objectType device, propertyIdentifier LocalDate 56). While it cannot be read, Present_Value is not re-derived: it keeps its last derived value, FALSE before the first.

Opt-in: a Calendar that is only added with BACnetStack_AddObject() keeps being served by your CallbackGetPropertyBool (Present_Value) and other callbacks. Calling this again for a Calendar that is already stack-held keeps its Date_List.

Date_List is read-only to BACnet clients by default. To let clients change it with WriteProperty, AddListElement and RemoveListElement, make it writable with BACnetStack_SetPropertyWritable() (Date_List, property identifier 23). The stack then accepts every BACnetCalendarEntry form (cl. 12.9.6).

A Schedule’s calendar-reference special event (BACnetStack_AddScheduleExceptionEventWithCalendarReference()) matches through the referenced Calendar’s Date_List only when that Calendar is stack-held.

Note

Requires the STACK_OPTION_OBJECT_TYPE_CALENDAR build option.

See also: BACnetStack_ObjectExists(), BACnetStack_RemoveObject()

BACnet reference: ANSI/ASHRAE 135-2024 clause 12.9 (Calendar Object Type).

Parameters

Parameter	Direction	Description
deviceInstance	in	The device instance that owns the Calendar object.
calendarObjectInstance	in	The Calendar object instance. It must already exist (BACnetStack_AddObject(deviceInstance, 6, N)).

Returns

True on success; false if the device or Calendar object does not exist, the instance is out of range, or Calendar support was not compiled.

Topic: Schedules, calendars, trend logs and other object configuration. Declared in CASBACnetStackDLL.h.