Matter Cluster 92 — Smoke CO Alarm Cluster

Cluster Identity

Revision history

Shadow Path Format

Cluster 92 values in the device shadow use this format:

endpoint_id / 92 / attribute_id

Example:

{
  "1/92/0": 0
}

Cluster 92 Features

The FeatureMap attribute (1/92/65532) is a bitmap. Each bit set means the device implements that feature and the attributes and commands that depend on it.

Example: FeatureMap = 0 means no optional feature is enabled; 3 means every feature listed above is enabled.

Data Types

AlarmStateEnum

ContaminationStateEnum

EndOfServiceEnum

ExpressedStateEnum

MuteStateEnum

SensitivityEnum

Cluster 92 Attributes

Cluster 92 defines 14 attributes plus the global attributes. Conformance: M mandatory, O optional, a feature code means "mandatory when that feature is present", square brackets mean "optional when …".

Global attributes

Attribute Details

Attribute 0 / 0x0000 — ExpressedState

Path example:

1/92/0

Indicates the visibly- and audibly-expressed state of the alarm. When multiple alarm conditions are being reflected in the server, this attribute indicates the condition with the highest priority. Priority order of conditions is determined by the manufacturer and is supplied as a part of certification procedure. If the value of ExpressedState is not Normal, the attribute corresponding to the value must NOT be Normal.

Values (ExpressedStateEnum):

Example:

{
  "1/92/0": 0
}

Attribute 1 / 0x0001 — SmokeState

Path example:

1/92/1

Indicates whether the device's smoke sensor is currently triggering a smoke alarm.

Values (AlarmStateEnum):

Example:

{
  "1/92/1": 0
}

Attribute 2 / 0x0002 — COState

Path example:

1/92/2

No condensed specification text is available for COState; use the type, conformance and constraint below together with the cluster description above.

Values (AlarmStateEnum):

Example:

{
  "1/92/2": 0
}

Attribute 3 / 0x0003 — BatteryAlert

Path example:

1/92/3

Indicates whether the power resource fault detection mechanism is currently triggered at the device. If the detection mechanism is triggered, this attribute is set to Warning or Critical, otherwise it is set to Normal. The battery state must also be reflected in the Power Source cluster representing the device's battery using the appropriate supported attributes and events. If the sensor cannot operate in the set state, the ExpressedState attribute is set to Inoperative.

Values (AlarmStateEnum):

Example:

{
  "1/92/3": 0
}

Attribute 4 / 0x0004 — DeviceMuted

Path example:

1/92/4

Indicates the whether the audible expression of the device is currently muted. Audible expression is typically a horn or speaker pattern.

Values (MuteStateEnum):

Example:

{
  "1/92/4": 0
}

Attribute 5 / 0x0005 — TestInProgress

Path example:

1/92/5

Indicates whether the device self-test is currently activated. If the device self-test is activated, this attribute is set to True, otherwise it is set to False.

Example:

{
  "1/92/5": true
}

Attribute 6 / 0x0006 — HardwareFaultAlert

Path example:

1/92/6

Indicates whether the hardware fault detection mechanism is currently triggered. If the detection mechanism is triggered, this attribute is set to True, otherwise it is set to False. When this attribute is set to True, and the sensor cannot operate in this state, the ExpressedState attribute is set to Inoperative.

Example:

{
  "1/92/6": true
}

Attribute 7 / 0x0007 — EndOfServiceAlert

Path example:

1/92/7

Indicates whether the end-of-service has been triggered at the device. This attribute is set to Expired when the device reaches the end-of-service.

Values (EndOfServiceEnum):

Example:

{
  "1/92/7": 0
}

Attribute 8 / 0x0008 — InterconnectSmokeAlarm

Path example:

1/92/8

Indicates whether the interconnected smoke alarm is currently triggering by branching devices. When the interconnected smoke alarm is being triggered, this attribute is set to Warning or Critical, otherwise it is set to Normal.

Values (AlarmStateEnum):

Example:

{
  "1/92/8": 0
}

Attribute 9 / 0x0009 — InterconnectCOAlarm

Path example:

1/92/9

No condensed specification text is available for InterconnectCOAlarm; use the type, conformance and constraint below together with the cluster description above.

Values (AlarmStateEnum):

Example:

{
  "1/92/9": 0
}

Attribute 10 / 0x000A — ContaminationState

Path example:

1/92/10

Indicates the contamination level of the smoke sensor.

Values (ContaminationStateEnum):

Example:

{
  "1/92/10": 0
}

Attribute 11 / 0x000B — SmokeSensitivityLevel

Path example:

1/92/11

Indicates the sensitivity level of the smoke sensor configured on the device.

Values (SensitivityEnum):

Example:

{
  "1/92/11": 0
}

Attribute 12 / 0x000C — ExpiryDate

Path example:

1/92/12

Indicates the date when the device reaches its stated expiry date. After the ExpiryDate has been reached, the EndOfServiceAlert must start to be triggered. To account for better customer experience across time zones, the EndOfServiceAlert may be delayed by up to 24 hours after the ExpiryDate. Similarly, clients may delay any actions based on the ExpiryDate by up to 24 hours to best align with the local time zone.

Example:

{
  "1/92/12": 1
}

Attribute 13 / 0x000D — Unmounted

Path example:

1/92/13

No condensed specification text is available for Unmounted; use the type, conformance and constraint below together with the cluster description above.

Example:

{
  "1/92/13": true
}

Cluster 92 Commands

Cluster 92 has 1 client-to-server command and 0 responses.

AcceptedCommandList

The AcceptedCommandList attribute lists the command IDs the endpoint actually implements:

endpoint_id / 92 / 65529

{
  "1/92/65529": [
    0
  ]
}

Bridge Command Payload Format

The bridge accepts Matter commands in this structure:

{
  "message_id": "1",
  "command": "device_command",
  "args": {
    "endpoint_id": 1,
    "cluster_id": 92,
    "command_name": "SelfTestRequest",
    "payload": {},
    "timed_request_timeout_ms": 1000
  }
}

For Cluster 92, always use "cluster_id": 92. Payload keys are the command field names in lowerCamelCase. Octet-string fields are base64-encoded. timed_request_timeout_ms is required for timed commands and ignored otherwise.

Command: SelfTestRequest

Purpose

This command must initiate a device self-test. The return status indicates whether the test was successfully initiated. Only one SelfTestRequest may be processed at a time. When the value of the ExpressedState attribute is any of SmokeAlarm, COAlarm, Testing, InterconnectSmoke, InterconnectCO, the device must NOT execute the self-test, and returns status code BUSY.

Command Identity

Payload Fields

This command has no payload fields.

Bridge Command Example

{
  "message_id": "1",
  "command": "device_command",
  "args": {
    "endpoint_id": 1,
    "cluster_id": 92,
    "command_name": "SelfTestRequest",
    "payload": {}
  }
}

Cluster 92 Events

Event 0 — SmokeAlarm

This event is generated when SmokeState attribute changes to either Warning or Critical state.

Event 1 — COAlarm

Event 2 — LowBattery

This event is generated when BatteryAlert attribute changes to either Warning or Critical state.

Event 3 — HardwareFault

This event is generated when the device detects a hardware fault that leads to setting HardwareFaultAlert to True.

This event has no fields.

Event 4 — EndOfService

This event is generated when the EndOfServiceAlert is set to Expired.

This event has no fields.

Event 5 — SelfTestComplete

This event is generated when the SelfTest completes, and the attribute TestInProgress changes to False.

This event has no fields.

Event 6 — AlarmMuted

This event is generated when the DeviceMuted attribute changes to Muted.

This event has no fields.

Event 7 — MuteEnded

This event is generated when DeviceMuted attribute changes to NotMuted.

This event has no fields.

Event 8 — InterconnectSmokeAlarm

This event is generated when the device hosting the server receives a smoke alarm from an interconnected sensor.

Event 9 — InterconnectCOAlarm

Event 10 — AllClear

This event is generated when ExpressedState attribute returns to Normal state.

This event has no fields.

SmartphoneKey Notes

• Smoke/CO alarms report SmokeState, COState and ExpressedState. Treat ExpressedState (attribute 2) as the single summary value.
• Shadow paths follow endpoint/92/attribute; attribute values that the device reports as unreadable are written as n/a.
• Attribute IDs, command IDs and enum values on this page come from the CSA Matter 1.6.1 data model; descriptions are condensed from the specification text.