ISO 16484-5:2017/Amd 1:2020

INTERNATIONAL ISO
STANDARD 16484-5
Sixth edition
2017-05
AMENDMENT 1
2020-04
Building automation and control
systems (BACS) —
Part 5:
Data communication protocol
AMENDMENT 1
Systèmes d'automatisation et de gestion technique du bâtiment —
Partie 5: Protocole de communication de données
AMENDEMENT 1
Reference number
ISO 16484-5:2017/Amd.1:2020(E)
©
ISO 2020

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ISO 16484-5:2017/Amd.1:2020(E)

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© ISO 2020
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Published in Switzerland
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ISO 16484-5:2017/Amd.1:2020(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national
standards bodies (ISO member bodies). The work of preparing International Standards is normally
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the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all
matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. International Standards are drafted in accordance
with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see
www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 205, Building environmental design, in
collaboration with the European Committee for Standardization (CEN) Technical Committee CEN/TC
247, Building Automation, Controls and Building Management, in accordance with the Agreement on
technical cooperation between ISO and CEN (Vienna Agreement).
A list of all parts in the ISO 16484 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
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ISO 16484-5:2017/Amd.1:2020(E)
(This foreword is not part of the standard. It is merely informative and does not contain requirements necessary for
conformance to the standard.)
FOREWORD

The purpose of this addendum is to add several independent substantive changes to the BACnet standard. The changes
are summarized below.

135-2016bd-1. Add Staging Object Type.
135-2016be-1. Add Lighting BIBBS and Device Profiles.
135-2016bi -1. Add Audit Reporting.
135-2016bi -2. Change DeviceCommunicaitonControlService for Audit Reporting.
135-2016bi -3. Modify Logging Objects to Allow for Extremely Large Logs.
135-2016bk -1. Expand the reserved range of BACnetPropertyIdentifier.
135-2016bl - 1. Clarify Result(-) response for failed WritePropertyMultiple requests.
135-2016bl - 2. Clarify ReadPropertyMultiple response on OPTIONAL when empty.
135-2016bl - 3. Clarify Out_Of_Service.
135-2016bm-1. Reduce allowed range for Usage Timeout.
135-2016bm-2. Specify design choices for MS/TP devices.
125-2016bm-3. Handle unwanted MS/TP frames in IDLE state.
135-2016bn-1. Make SCHED BIBBs consistent on supported datatypes, and add BOOLEAN.
135-2016bn-2. Clarify COV and COVP related BIBBs.
135-2016bn-3. Clock is required for support of AE-ACK-A.
135-2016bp-1. Make rules for POST consistent with rules for PUT.
135-2016bp-2. Make 'type' consistent at all levels and introduce 'effectiveType'.
135-2016bp-3. Fully specify the behavior of "includes".
135-2016bp-4. Remove the path syntax from the 'select' query parameter.
135-2016bp-5. Resolve conflicting statements about configuring external authorization servers.
135-2016bp-6. Remove incorrect table for callback formats.
135-2016bp-7. Allow plain text POSTs for primitive data.
135-2016bp-8. Allow extended error numbers.
135-2016bp-9. Add new error numbers.
135-2016bp-10. Add formal definition for JSON equivalent to XML's .
135-2016bp-11. Specify 'name' safety check for setting data.
135-2016bp-12. Specify how to evaluate relative paths for collections of links.
135-2016bp-13. Allow proprietary categories for the 'metadata' query.
135-2016bq-1. Fix the Absentee_Limit property of the Access Credential object type.
135-2016bq-2. Ensure that the denied or granted access event is generated last.

In the following document, language to be added to existing clauses of EN ISO 16484-5 and Addenda is indicated
through the use of italics, while deletions are indicated by strikethrough. Where entirely new subclauses are proposed to
be added, plain type is used throughout.

The use of placeholders like X, Y, Z, X1, X2, etc., should not be interpreted as literal values of the final standard. These
placeholders will be assigned actual numbers/letters only with incorporation of this addendum into the standard for
republication.

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ISO 16484-5:2017/Amd.1:2020(E)
Building automation and control systems (BACS) —
Part 5:
Data communication protocol
AMENDMENT 1
135-2016bd-1 Add a Staging Object Type

Rationale

The Staging object type provides a way for BACnet devices to map analog values onto multiple Binary Value, Binary
Output, or Binary Lighting Output objects.

A common use case is in lighting applications, where a level, identified by a numeric value, sets the appropriate values of
multiple binary outputs (on or off).

Support of this new object type is excluded from all data sharing BIBBs for life safety and access control.



[Insert new Clause 12.X]

12.X Staging Object Type
The Staging object type defines a standardized object whose properties represent the externally visible characteristics of a
staged value. A "Staging" maps a numeric value onto multiple discrete ranges that define individual “stages” (Nstages).
Each Staging object is associated with a collection of references to binary valued objects (N ). Each Staging object
references
may therefore control Binary Output, Binary Value, or Binary Lighting Output objects. Every stage specifies an arbitrary
combination of ACTIVE/INACTIVE values to be written to these referenced objects. Stages are defined by a limit, a
deadband, and the collection of values for the referenced objects.

Figure 12-X shows a typical Staging object application with four stages (Nstages =4) and two referenced binary objects
(N = 2).
references

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ISO 16484-5:2017/Amd.1:2020(E)
Bit cleared -> INACTIVE
Bit set -> ACTIVE
Max_Pres_value = Stages[4].Limit
Stages[4].Values =
Stage 4
Stages[3].Limit
STAGE Stage 33 Stages[3].Values =
Stages[2].Limit
STAGE Stage 22 Stages[2].Values =
Stages[1].Limit
Stages[1].Values =
STAGE Stage 11
Min_Pres_Value
Target_References[1]={Device 2222, Binary Output 5}
Target_References[2]={Device 3333, Binary Output 27}

Figure 12-X. Typical Staging Application (Nstages =4, Nreferences = 2)


Present_Value > (Stages[2].Limit + Stages[2].Deadband)
Present_Value
Present_Stage = 3
Stage 3
Stages[2].Deadband
Stages[2].Limit
Stages[2].Deadband
Stage 2
Present_Value < (Stages[2].Limit - Stages[2].Deadband)
Present_Stage = 2
t
Present_Stage: 2 3 2 3 2

Figure 12-X2. Stage Limits incorporate hysteresis through the use of a Deadband around each Limit


Stages are defined by limits with a symmetrical deadband. A deadband greater than zero is used to prevent unwanted
oscillation when the Present_Value is close to a limit. As the Present_Value increases, if it rises above the limit for a
stage plus the deadband for that stage, the Present_Stage transitions to that stage+1. Similarly, as the Present_Value
decreases, it must fall below the limit for a stage minus the deadband for that stage before Present_Stage transitions to
that stage. The deadband is allowed to be zero (0.0).

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Present_Value

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ISO 16484-5:2017/Amd.1:2020(E)
1)
Present_Value
Write 18.0
18.0
Stages
Read
Limit Deadband Values
[4] 40.0 1.0 0 1 1 1 1 1
18.0 is in Stage 2
[3] 30.0 1.0 0 1 1 0 0 0
2)
[2] 20.0 1.0 1 1 1 0 0 0
Present_Stage
[1] 10.0 1.0 1 0 0 0 0 0
2
Target_References
Values Bit Binary PV to Write
Device 7, Binary Output, 62 Bit(0) = 1 ACTIVE
[1]
Device 28, Binary Output, 47 Bit(1) = 1 ACTIVE
[2]
Device 17, Binary Output, 49 Bit(2) = 1 ACTIVE
[3]
Device 6, Binary Output, 116 Bit(3) = 0 INACTIVE
[4]
(local), Binary Output, 6 Bit(4) = 0 INACTIVE
[5] Priority_For_Writing
Device 112, Binary Output, 7 Bit(5) = 0 INACTIVE 8
[6]
To: Object Identifier Property Identifier Property Value Priority
3)
Device 7 WriteProperty Binary Output, 62 Present_Value ACTIVE 8
Device 28 WriteProperty Binary Output, 47 Present_Value ACTIVE 8
Initiate
Device 17 WriteProperty Binary Output, 49 Present_Value ACTIVE 8
WriteProperty
Requests
Device 6 WriteProperty Binary Output, 116 Present_Value INACTIVE 8
(local) (WriteProperty) Binary Output, 6 Present_Value INACTIVE 8
Device 112 WriteProperty Binary Output, 7 Present_Value INACTIVE 8

Figure 12-X3. Pipeline of operations when Present_Value is written


Staging objects may optionally support intrinsic reporting to facilitate the reporting of fault conditions. Staging objects
that support intrinsic reporting shall apply the NONE event algorithm.

The object and its properties are summarized in Table 12-X and described in detail in this clause.

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ISO 16484-5:2017/Amd.1:2020(E)
Table 12-X. Properties of the Staging Object Type
Property Identifier Property Datatype Conformance Code
Object_Identifier BACnetObjectIdentifier R
Object_Name CharacterString R
Object_Type BACnetObjectType R
Present_Value REAL W
Present_Stage Unsigned R
1
Stages BACnetARRAY[N] of BACnetStageLimitValue R
1
Stage_Names BACnetARRAY[N] of CharacterString O
Status_Flags BACnetStatusFlags R
Event_State BACnetEventState R
Reliability BACnetReliability R
Out_Of_Service BOOLEAN R
Description CharacterString O
Units BACnetEngineeringUnits R
2
Target_References BACnetARRAY[N] of BACnetDeviceObjectReference R
Priority_For_Writing Unsigned(1.16) R
Default_Present_Value REAL O
Min_Pres_Value REAL R
Max_Pres_Value REAL R
3
COV_Increment REAL O
4,5
Notification_Class Unsigned O
4,5
Event_Enable BACnetEventTransitionBits O
4,5
Acked_Transitions BACnetEventTransitionBits O
4,5
Notify_Type BACnetNotifyType O
4,5
Event_Time_Stamps BACnetARRAY[3] of BACnetTimeStamp O
5,6
Event_Message_Texts BACnetARRAY[3] of CharacterString O
5
Event_Message_Texts_Config BACnetARRAY[3] of CharacterString O
4,5
Event_Detection_Enable BOOLEAN O
Reliability_Evaluation_Inhibit BOOLEAN O
Property_List BACnetARRAY[N] of BACnetPropertyIdentifier R
7,8,9
Value_Source BACnetValueSource O
Tags BACnetARRAY[N] of BACnetNameValue O
Profile_Location CharacterString O
Profile_Name CharacterString O
1
The array size of this property is Nstages.
2
The array size of this property is N .
references
3
This property is required if the object supports COV reporting.
4
These properties are required if the object supports intrinsic reporting.
5
These properties shall be present only if the object supports intrinsic reporting.
6
This property, if present, is required to be read-only.
7
This property is required if the object supports the value source mechanism.
8
This property shall be present only if the object supports the value source mechanism.
9
This property shall be writable as described in Clause 19.5.

12.X .1 Object_Identifier
This property, of type BACnetObjectIdentifier, is a numeric code that is used to identify the object. It shall be unique
within the BACnet device that maintains it.
12.X .2 Object_Name
This property, of type CharacterString, shall represent a name for the object that is unique within the BACnet device that
maintains it. The minimum length of the string shall be one character. The set of characters used in the Object_Name
shall be restricted to printable characters.
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ISO 16484-5:2017/Amd.1:2020(E)
12.X .3 Object_Type
This property, of type BACnetObjectType, indicates membership in a particular object type class. The value of this
property shall be STAGING.
12.X .4 Present_Value
This property, of type REAL, indicates the current value, in engineering units, of the Staging object. If Present_Value is
written with a value less than Min_Pres_Value, then it shall be clamped to Min_Pres_Value. If Present_Value is written
with a value greater than Max_Pres_Value, then it shall be clamped to Max_Pres_Value.

Whenever Present_Value is changed, the new value shall be compared with the 'Limit' values for the entire Stages array
using the following algorithm:


ops = current Present_Stage
npv = new Present_Value

//check if value should remain in the current stage
If (ops != 0) then
upperBound = Stages[ops].Limit + Stages[ops].Deadband
if (ops > 1) then
 lowerBound = Stages[ops-1].Limit - Stages[ops-1].Deadband
else
 lowerBound = Min_Pres_Value
endif
if (npv <= upperBound AND npv >= lowerBound) then
 Present_Value = npv
 exit algorithm //no change to current stage, stop algorithm
endif
endif

// calculate the new stage
Present_Stage = Nstages
for (i=1 to Nstages-1, step +1)
if npv <= (Stages[i].Limit) then
 Present_Stage = i
 exit for //found the correct stage, stop iteration
endif
next i

Present_Value = npv

Figure 12-X4. Pseudocode Algorithm for Evaluating Present_Value and Present_Stage

12.X.4.1 Writing to Referenced Objects
Changes to Present_Stage shall cause a write of ACTIVE or INACTIVE to the corresponding object’s Present_Value for
each Target_References array element. For each bit (Index = 0 to N -1) in the Stages[Present_Stage].Values
references
bitstring, if the bit is set (1), an ACTIVE value shall be written, or if clear (0), then an INACTIVE value shall be written
to the Target_References[Index +1] object's Present_Value.

Writes to Present_Value that subsequently trigger writing to referenced objects due to reevaluation of Present_Stage, are
not expected to wait until the reference writes occur before returning a Result(+) or Result(-) for the write to
Present_Value. Subsequently if any write to a referenced object fails, Reliability shall be changed to
COMMUNICATION_FAILURE. The COMMUNICATION_FAILURE shall remain in effect until all reference writes
have been completed successfully. How a particular implementation handles other failures during writing to referenced
objects shall be a local matter except that Reliability shall indicate a value other than NO_FAULT_DETECTED.

The order of evaluation of references and any referenced object write delay shall be a local matter.
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ISO 16484-5:2017/Amd.1:2020(E)
12.X.5 Present_Stage
This property, of type Unsigned, shall indicate the array index (1 to Nstages) that corresponds to the current active stage or
0 meaning that the Present_Stage has not yet been initialized. Upon device restart, or when the Stages property is written
to any of its elements, or the size of the Stages array changes, Present_Stage shall be set to 0 temporarily and then
Present_Value shall be reevaluated as described in Clause 12.X.4.1.

Attempts to read Present_Stage when it is internally set to 0 shall return a Result(-) with an 'Error Class' of PROPERTY
and an 'Error Code' of VALUE_NOT_INITIALIZED.
12.X.6 Stages
This property, of type BACnetARRAY[N] of BACnetStageLimitValue, is an array representing the stages by limit,
desired present values for the objects referenced by Target_References, and deadband. The size of the array is N ,
stages
where Nstages shall be greater than 1. BACnetStageLimitValue is a tuple consisting of the following fields:

Limit REAL
Values BIT STRING
Deadband REAL

The 'Limit' values for all elements shall be strictly ascending, such that:

for Index=1 to Nstages-1
{
  lowerbound = (Stages[Index].Limit + Stages[Index].Deadband)
  upperbound = (Stages[Index+1].Limit - Stages[Index+1].Deadband)
  lowerbound <= upperbound
}

If any of the stages do not meet this criterion, then the Reliability property shall have a value of
CONFIGURATION_ERROR.

- 1)
The bits in 'Values' correspond to references in the Target_References array, such that bit (Index = 0 to Nreferences
corresponds to Target_References[Index + 1], etc. The length of the 'Values' bitstring shall be Nreferences bits.

The 'Deadband' shall be zero or positive. A negative value for 'Deadband' shall cause the value of Reliability to be
CONFIGURATION_ERROR.

If the size of the Stages array is increased, then the new array elements, for which no initial value is provided, shall be
initialized to contain 'Limit' = 0.0, 'Deadband' = 0.0, and 'Values' = {0…0}, and the value of Reliability shall be set to
CONFIGURATION_ERROR.

If the size of the Stages array is less than 2, then the Reliability property shall have a value of
CONFIGURATION_ERROR.

If Reliability has the value CONFIGURATION_ERROR, then Present_Value shall be set to Min_Pres_Value and
Present_Stage to 1.

].Limit becomes smaller than Present_Value, then Present_Value shall be set to Stages[N ].Limit.
If Stages[Nstages stages

If the Stages property is written, the value of Present_Stage shall be reevaluated and corresponding writes of new values
to Target_References’ objects shall be triggered.

If the size of this array is changed, the size of the Stage_Names array shall also be changed to the same size.
12.X.7 Stage_Names
This property, of type BACnetARRAY[N] of CharacterString, is an array representing a name for each stage. The
number of array elements in Stage_Names shall be the same as the number of array elements in the Stages property.
Stage_Names[1] shall correspond to the name for Present_Stage=1. Stage_Names[2] shall correspond to the name for
Present_Stage=2, etc.

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ISO 16484-5:2017/Amd.1:2020(E)
If the size of this array is changed, the size of the Stages array shall also be changed to the same size. If the size of
Stage_Names is increased, then it shall be a local matter what the uninitialized array elements contain.
12.X.8 Status_Flags
This property, of type BACnetStatusFlags, represents four Boolean flags that indicate the general "health" of a Staging
object. Three of the flags are associated with the values of other properties of this object. A more detailed status could be
determined by reading the properties that are linked to these flags. The relationship between individual flags is not
defined by the protocol. The four flags are
{IN_ALARM, FAULT, OVERRIDDEN, OUT_OF_SERVICE}
where:

IN_ALARM Logical FALSE (0) if the Event_State property has a value of NORMAL, otherwise logical
TRUE (1).

FAULT Logical TRUE (1) if the Reliability property does not have a value of
NO_FAULT_DETECTED, otherwise logical FALSE (0).

OVERRIDDEN Always logical FALSE (0).

OUT_OF_SERVICE Logical TRUE (1) if the Out_Of_Service property has a value of TRUE, otherwise logical
FALSE(0).

If the object supports event reporting, then this property shall be the pStatusFlags parameter for the object's event
algorithm. See Clause 13.3 for event algorithm parameter descriptions.
12.X.9 Event_State
The Event_State property, of type BACnetEventState, is included in order to provide a way to determine whether this
object has an active event state associated with it (see Clause 13.2.2.1). If the object supports event reporting, then the
Event_State property shall indicate the event state of the object. If the object does not support event reporting, then the
value of this property shall be NORMAL.

12.X.10 Reliability
The Reliability property, of type BACnetReliability, provides an indication that the properties of the Staging object are in
a consistent state and that Target_References are being reliably written. See Clauses 12.X.4.1, 12.X.6, and 12.X.17.

Table 12-X2 summarizes scenarios when Reliability has a value other than NO_FAULT_DETECTED.

Table 12-X2. Reliability Scenarios
Scenario Reliability Value See Clause
Communication error when writing COMMUNICATION_FAILURE 12.X.4.1
Non-communication-related failure when writing Local Matter 12.X.4.1
'Limit' values out of order CONFIGURATION_ERROR 12.X.6
'Deadband' is negative CONFIGURATION_ERROR 12.X.6
Stages array size is increased CONFIGURATION_ERROR 12.X.6
Min_Pres_Value is >=
CONFIGURATION_ERROR 12.X.17
(Stages[1].Limit - Stages[1].Deadband)

12.X.11 Out_Of_Service
The Out_Of_Service property, of type BOOLEAN, is an indication whether (TRUE) or not (FALSE) the Present_Value
property is controllable by software local to the BACnet device.

When Out_Of_Service is TRUE:
a) changes to the Present_Value property are decoupled from the Target_References. This means that the
objects referenced by Target_References shall not be updated;
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ISO 16484-5:2017/Amd.1:2020(E)
b) the Present_Value property and the Reliability property, if capable of taking on values other than
NO_FAULT_DETECTED, shall be writable to allow simulating specific conditions or for testing purposes;
c) other functions that depend on the state of the Present_Value or Reliability properties shall respond to
changes made to these properties, as if those changes had occurred while the object was in service;

Restrictions on writing to the Present_Value property by software local to the BACnet device do not apply to local human-
machine interfaces.

When Out_Of_Service becomes FALSE, it shall trigger updating of referenced objects as described in Clause 12.X.4.1.
12.X.12 Description
This property, of type CharacterString, is a string of printable characters whose content is not restricted.
12.X.13 Units
This property, of type BACnetEngineeringUnits, indicates the measurement units of this object. See the
BACnetEngineeringUnits ASN.1 production in Clause 21 for a list of engineering units defined by this standard.
12.X.14 Target_References
This property, of type BACnetARRAY[N] of BACnetDeviceObjectReference, is an array representing references to
Binary Output, Binary Value, or Binary Lighting Output objects. The size of the array is N . The
references
Target_References array elements [Index = 1 to Nreferences] shall correspond to the bit(Index - 1) of all 'Values' bitstrings
of the Stages property.

If the property is restricted to referencing objects within the containing device, an attempt to write to a reference to an
object outside the containing device into this property shall cause a Result(-) to be returned with an error class of
PROPERTY and an error code of OPTIONAL_FUNCTIONALITY_NOT_SUPPORTED. Uninitialized
Target_References array elements shall be given the instance number 4194303. A Target_References array element
whose instance number is equal to 4194303 shall be considered uninitialized and shall be ignored in all operations that
may use that reference.

If the size of this array is changed, the size of the 'Values' bitstrings of the Stages property shall also be changed to the
same size. If the bitstring length is increased, added bits shall be cleared (0).
12.X.15 Priority_For_Writing
This property defines the priority at which the referenced properties are commanded. It corresponds to the 'Priority'
parameter of the WriteProperty service. It is an unsigned integer in the range 1-16, with 1 being considered the highest
priority and 16 the lowest. See Clause 19.2.
12.X.16 Default_Present_Value
This optional property, of type REAL, defines the value to be used for Present_Value upon device restart. Upon restart
Default_Present_Value shall be copied to Present_Value and cause the reevaluation of Present_Value as described in
Clause 12.X.4.
12.X.17 Min_Pres_Value
This property, of type REAL, represents the minimum value for Present_Value. Min_Pres_Value shall always be strictly
less than the quantity (Stages[1].Limit - Stages[1].Deadband).

If a change to Min_Pres_Value, Stages[1].Limit, or Stages[1].Deadband violates this rule, then the Reliability property
shall have a value of CONFIGURATION_ERROR. If a change to Min_Pres_Value causes it to be greater than
Present_Value, then Present_Value shall be written with Min_Pres_Value.
12.X.18 Max_Pres_Value
This read-only property, of type REAL, represents the maximum value for Present_Value. This value shall be defined as
the ‘Limit’ of the last entry of the Stages property array (i.e., Stages[N ].Limit).
stages

If the size of the Stages array is zero, then Max_Pres_Value shall be equal to Min_Pres_Value.
12.X.19 COV_Increment
This property, of type REAL, shall specify the minimum change in Present_Value that will cause a COV notification to
be issued to subscriber COV-clients. This property is required if COV reporting is supported by this object.
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ISO 16484-5:2017/Amd.1:2020(E)
12.X.20 Notification_Class
This property, of type Unsigned, shall specify the instance of the Notification Class object to use for event-notification-
distribution.
12.X.21 Event_Enable
This property, of type BACnetEventTransitionBits, shall convey three flags that separately enable and disable the
distribution of TO_OFFNORMAL, TO_FAULT, and TO_NORMAL notifications (see Clause 13.2.5). A device is
allowed to restrict the set of supported values for this property but shall support (T, T, T) at a minimum.
12.X.22 Acked_Transitions
This read-only property, of type BACnetEventTransitionBits, shall convey three flags that separately indicate the
acknowledgment state for TO_OFFNORMAL, TO_FAULT, and TO_NORMAL events (see Clause 13.2.2.1.5). Each
flag shall have the value TRUE if no event of that type has ever occurred for the object.
12.X.23 Notify_Type
This property, of type BACnetNotifyType, shall convey whether the notifications generated by the object should be
Events or Alarms. The value of the property is used as the value of the 'Notify Type' service parameter in event
notifications generated by the object.
12.X.24 Event_Time_Stamps
This read-only property, of type BACnetARRAY[3] of BACnetTimeStamp, shall convey the times of the last
TO_OFFNORMAL, TO_FAULT, and TO_NORMAL events (see Clause 13.2.2.1). Timestamps of type Time or Date
shall have X'FF' in each octet, and Sequence Number timestamps shall have the value 0 if no event of that type has ever
occurred for the object.
12.X.25 Event_Message_Texts
This read-only property, of type BACnetARRAY[3] of CharacterString, shall convey the message text values of the last
TO_OFFNORMAL, TO_FAULT, and TO_NORMAL events (see Clause 13.2.2.1). If a particular type of event has yet
to occur, an empty string shall be stored in the respective array element.
12.X.26 Event_Message_Texts_Config
This property, of type BACnetARRAY[3] of CharacterString, contains the character strings which are the basis for the
'Message Text' parameter for the event notifications of TO_OFFNORMAL, TO_FAULT, and TO_NORMAL events,
respectively, generated by this object. The character strings may optionally contain proprietary text substitution codes to
incorporate dynamic information such as date and time or other information.
12.X.27 Event_Detection_Enable
This property, of type BOOLEAN, indicates whether (TRUE) or not (FALSE) intrinsic reporting is enabled in the object
and controls whether (TRUE) or not (FALSE) the object will be considered by event summarization services.

This pr
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