Access Point

An Access Point object represents a controlled entry or exit, usually a reader at a door. It decides whether a presented credential is allowed through and records the result. Clients read it to see the latest access event and to set up how strictly it checks.

Typical uses

• A card reader at an office entrance
• An exit reader that counts people leaving a zone
• A turnstile that needs card and PIN together
• A door that locks out after repeated failed attempts

Key properties

Property	What it holds
Authentication_Status	Shows whether the point is ready, waiting for more factors, or otherwise busy.
Active_Authentication_Policy	Picks which entry of the policy list is in force right now.
Access_Event	The most recent access event, such as granted or denied for a stated reason.
Access_Event_Credential	The credential involved in the latest event.
Access_Doors	The Access Door objects this point operates. It reads as an empty array until your application reports a size for it.
Zone_To	The zone a person enters through this point.

How it behaves

Intrinsic reporting uses the ACCESS_EVENT algorithm, for both alarm-type events and ordinary transaction events. Each new access event is sent to the recipients listed in the Recipient_List of the object’s Notification Class.

With the CAS BACnet Stack

Enable it with the STACK_OPTION_OBJECT_TYPE_ACCESS_POINT build option, which also turns on the Access Credential type. Add each object with BACnetStack_AddObject; the stack does not serve its other property values on its own, so supply them through your property callbacks. The customer interface cannot arm access-event reporting: CASBACnetStackDLL.h has no setter for the ACCESS_EVENT algorithm. If your product needs it, contact Chipkin.

Related object types

Access Door, Access Zone, Access Credential

Properties

The properties ASHRAE 135-2024 clause 12.31 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	""
Status_Flags	BACnetStatusFlags	R	yes	no	Built by the stack from your callbacks.
Event_State	BACnetEventState	R	yes	no	0
Reliability	BACnetReliability	R	yes	no	0
Out_Of_Service	Boolean	R	yes	no	false
Authentication_Status	BACnetAuthenticationStatus	R	yes	no	0
Active_Authentication_Policy	Unsigned	R	yes	yes	0
Number_Of_Authentication_Policies	Unsigned	R	yes	no	0
Authentication_Policy_List	BACnetARRAY[N] of BACnetAuthenticationPolicy	O1	no	no	No default: the read fails.
Authentication_Policy_Names	BACnetARRAY[N] of CharacterString	O1	no	no	""
Authorization_Mode	BACnetAuthorizationMode	R	yes	no	0
Verification_Time	Unsigned	O	no	no	0
Lockout	Boolean	O2	yes	yes	false
Lockout_Relinquish_Time	Unsigned	O	yes	no	0
Failed_Attempts	Unsigned	O	no	no	0
Failed_Attempt_Events	BACnetLIST of BACnetAccessEvent	O	no	no	0
Max_Failed_Attempts	Unsigned	O3	no	no	0
Failed_Attempts_Time	Unsigned	O3	no	no	0
Threat_Level	BACnetAccessThreatLevel	O	yes	yes	0
Occupancy_Upper_Limit_Enforced	Boolean	O	no	no	false
Occupancy_Lower_Limit_Enforced	Boolean	O	no	no	false
Occupancy_Count_Adjust	Boolean	O	no	no	false
Accompaniment_Time	Unsigned	O	no	no	0
Access_Event	BACnetAccessEvent	R	yes	no	0
Access_Event_Tag	Unsigned	R	yes	no	0
Access_Event_Time	BACnetTimeStamp	R	yes	no	A date-time stamp with every octet X'FF' (no update yet).
Access_Event_Credential	BACnetDeviceObjectReference	R	yes	no	A reference to Access Credential instance 4194303 (none).
Access_Event_Authentication_Factor	BACnetAuthenticationFactor	O	no	no	A factor of format UNDEFINED with an empty value.
Access_Doors	BACnetARRAY[N] of BACnetDeviceObjectReference	R	yes	no	No default: the read fails.
Priority_For_Writing	Unsigned(1..16)	R	yes	no	0
Muster_Point	Boolean	O	no	no	false
Zone_To	BACnetDeviceObjectReference	O	no	no	A reference to Access Zone instance 4194303 (none).
Zone_From	BACnetDeviceObjectReference	O	no	no	A reference to Access Zone instance 4194303 (none).
Notification_Class	Unsigned	O4,6	no	no	0
Transaction_Notification_Class	Unsigned	O	no	no	0
Access_Alarm_Events	BACnetLIST of BACnetAccessEvent	O4,6	no	no	0
Access_Transaction_Events	BACnetLIST of BACnetAccessEvent	O4,6	no	no	0
Event_Enable	BACnetEventTransitionBits	O4,6	no	no	An empty bit string.
Acked_Transitions	BACnetEventTransitionBits	O4,6	no	no	An empty bit string.
Notify_Type	BACnetNotifyType	O4,6	no	no	0
Event_Time_Stamps	BACnetARRAY[3] of BACnetTimeStamp	O4,6	no	no	No default: the read fails.
Event_Message_Texts	BACnetARRAY[3] of CharacterString	O6	no	no	""
Event_Message_Texts_Config	BACnetARRAY[3] of CharacterString	O6	no	no	""
Event_Detection_Enable	Boolean	O4,6	no	no	false
Event_Algorithm_Inhibit_Ref	BACnetObjectPropertyReference	O6	no	no	No default: the read fails.
Event_Algorithm_Inhibit	Boolean	O6,7	no	no	false
Reliability_Evaluation_Inhibit	Boolean	O	no	no	false
Property_List	BACnetARRAY[N] of BACnetPropertyIdentifier	R	yes	no	Held by the stack.
Audit_Level	BACnetAuditLevel	O8	not in profile	not in profile	No default: the read fails.
Auditable_Operations	BACnetAuditOperationFlags	O8	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	""