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BACnetStack_SetIntrinsicChangeOfStateAlgorithmBool

bool BACnetStack_SetIntrinsicChangeOfStateAlgorithmBool(
const uint32_t deviceInstance,
const uint16_t objectType,
const uint32_t objectInstance,
const bool alarmValue,
const uint32_t timeDelay,
const bool useTimeDelayNormal,
const uint32_t timeDelayNormal,
const bool enable);

Enables the Intrinsic Change of State Algorithm with a BOOLEAN primitive for an object.

The object must exist and have alarms and events enabled by BACnetStack_SetAlarmsAndEventsForObjectEnabled(…, enabled=true) - an Event Enrollment object carries its own and needs no such call; otherwise this returns false.

This function will enable the required properties and store the initial values in memory.

BACnet reference: ANSI/ASHRAE 135-2024 clause 13.3.2 (CHANGE_OF_STATE Event Algorithm).

Parameter Direction Description
deviceInstance in The instance number of the device that owns this object.
objectType, objectInstance in The object for alarms and events: one BACnet Object Identifier, carried as two parameters (see the API conventions).
alarmValue in The BOOLEAN Present_Value that puts the object into OFFNORMAL (135-2024 cl. 13.3.2 pAlarmValues). On a Binary Input or Binary Value it is stored as BACnetBinaryPV (true = active, false = inactive). Each call REPLACES the previous alarm value (on an Event Enrollment, the whole alarm-value list), so calling it again with the other value re-arms the object on that value.
timeDelay in How long, in seconds, an offnormal condition has to persist before the event state changes to offnormal.
useTimeDelayNormal in Whether to use a different time delay value for the timeDelayNormal, or just use the timeDelay value.
timeDelayNormal in How long, in seconds, a normal condition has to persist before the event state returns to normal.
enable in Initial inhibit state, inverted - NOT a remove. true arms the algorithm; false leaves it armed but INHIBITED through the object’s Event_Algorithm_Inhibit property (or Reliability_Evaluation_Inhibit for a fault algorithm). Both of those properties are made WRITABLE by BACnetStack_SetAlarmsAndEventsForObjectEnabled(), so a remote client can change the state afterwards. To genuinely remove an armed algorithm, disable the object with BACnetStack_SetAlarmsAndEventsForObjectEnabled(…, enabled=false). Recommended value: true

True on success; false if the device or object does not exist, the object type does not support this algorithm, or Alarm-and-Event support was not compiled (STACK_OPTION_ALARMS_AND_EVENTS).

Topic: Alarms and events. Declared in CASBACnetStackDLL.h.