Device Management¶

Service Base¶

Service handler registration and dispatch per ASHRAE 135-2016.

type bac_py.services.base.ConfirmedHandler = Callable[[int, bytes, BACnetAddress], Awaitable[bytes | None]]¶

type bac_py.services.base.UnconfirmedHandler = Callable[[int, bytes, BACnetAddress], Awaitable[None]]¶

class bac_py.services.base.ServiceRegistry[source]¶

Bases: object

Registry for BACnet service request handlers.

Maps service choice numbers to handler coroutines for both confirmed and unconfirmed services.

register_confirmed(service_choice, handler)[source]¶

Parameters:

service_choice (int) – Confirmed service choice number.
handler (TypeAliasType) – Async handler coroutine.

Return type:

None

register_unconfirmed(service_choice, handler)[source]¶

Parameters:

service_choice (int) – Unconfirmed service choice number.
handler (TypeAliasType) – Async handler coroutine.

Return type:

None

async dispatch_confirmed(service_choice, request_data, source)[source]¶

Dispatch an incoming confirmed request to its handler.

Parameters:

service_choice (int) – Confirmed service choice number.
request_data (bytes) – Raw service request bytes.
source (BACnetAddress) – Source address of the request.

Return type:

bytes | None

Returns:

Service ACK data for ComplexACK, or None for SimpleACK.

Raises:

BACnetRejectError – If no handler is registered for the service.

async dispatch_unconfirmed(service_choice, request_data, source)[source]¶

Dispatch an incoming unconfirmed request to its handler.

If no handler is registered for service_choice, the request is silently ignored (per Clause 5.4.2 – no reject/abort is sent for unconfirmed services).

Parameters:

service_choice (int) – Unconfirmed service choice number.
request_data (bytes) – Raw service request bytes.
source (BACnetAddress) – Source address of the request.

Return type:

None

has_confirmed_handler(service_choice)[source]¶

Check whether a confirmed service handler is registered.

Parameters:: service_choice (int) – Confirmed service choice number.
Return type:: bool
Returns:: True if a handler is registered.

has_unconfirmed_handler(service_choice)[source]¶

Check whether an unconfirmed service handler is registered.

Parameters:: service_choice (int) – Unconfirmed service choice number.
Return type:: bool
Returns:: True if a handler is registered.

Common Types¶

Shared BACnet service data types per ASHRAE 135-2016 Clause 21.

class bac_py.services.common.BACnetPropertyValue(property_identifier, property_array_index=None, value=b'', priority=None)[source]¶

Bases: object

BACnetPropertyValue per Clause 21.

BACnetPropertyValue ::= SEQUENCE {
    propertyIdentifier  [0] BACnetPropertyIdentifier,
    propertyArrayIndex  [1] Unsigned OPTIONAL,
    value               [2] ABSTRACT-SYNTAX.&Type,
    priority            [3] Unsigned (1..16) OPTIONAL
}

The value field contains raw application-tagged bytes.

Parameters:

property_identifier (PropertyIdentifier)
property_array_index (int | None)
value (bytes)
priority (int | None)

property_identifier: PropertyIdentifier¶

property_array_index: int | None¶

value: bytes¶

priority: int | None¶

encode()[source]¶

Encode BACnetPropertyValue.

Return type:: bytes
Returns:: Encoded bytes for this property value sequence.

classmethod decode_from(data, offset=0)[source]¶

Decode BACnetPropertyValue from data at a given offset.

Parameters:

data (memoryview | bytes) – Raw bytes containing encoded property value data.
offset (int (default: 0)) – Byte offset to start decoding from.

Return type:

tuple[BACnetPropertyValue, int]

Returns:

Tuple of (decoded BACnetPropertyValue, new offset).

Raises:

BACnetRejectError – If priority is outside the 1–16 range.

Errors¶

BACnet protocol error types per ASHRAE 135-2016 Clause 18.

exception bac_py.services.errors.BACnetBaseError[source]¶

Bases: Exception

Base exception for BACnet protocol errors.

exception bac_py.services.errors.BACnetError(error_class, error_code, error_data=b'')[source]¶

Bases: BACnetBaseError

BACnet Error-PDU received (Clause 18).

Contains error class and code per the specification.

Parameters:

error_class (ErrorClass)
error_code (ErrorCode)
error_data (bytes)

Return type:

None

exception bac_py.services.errors.BACnetRejectError(reason)[source]¶

Bases: BACnetBaseError

BACnet Reject-PDU received (Clause 18.9).

Indicates a syntax or protocol error in the request.

Parameters:: reason (RejectReason)
Return type:: None

exception bac_py.services.errors.BACnetAbortError(reason)[source]¶

Bases: BACnetBaseError

BACnet Abort-PDU received (Clause 18.10).

Indicates the transaction was aborted.

Parameters:: reason (AbortReason)
Return type:: None

exception bac_py.services.errors.BACnetTimeoutError[source]¶

Bases: BACnetBaseError

Request timed out after all retries exhausted.

Device Management¶

Device management services per ASHRAE 135-2016 Clause 16.

DeviceCommunicationControl (Clause 16.1), ReinitializeDevice (Clause 16.4), TimeSynchronization (Clause 16.7), and UTCTimeSynchronization (Clause 16.8).

class bac_py.services.device_mgmt.DeviceCommunicationControlRequest(enable_disable, time_duration=None, password=None)[source]¶

Bases: object

DeviceCommunicationControl-Request (Clause 16.1.1).

DeviceCommunicationControl-Request ::= SEQUENCE {
    timeDuration  [0] Unsigned16 OPTIONAL,
    enable-disable [1] ENUMERATED,
    password      [2] CharacterString (1..20) OPTIONAL
}

Parameters:

enable_disable (EnableDisable)
time_duration (int | None)
password (str | None)

enable_disable: EnableDisable¶

time_duration: int | None¶

password: str | None¶

encode()[source]¶

Encode DeviceCommunicationControl-Request service parameters.

Return type:: bytes
Returns:: Encoded service request bytes.

classmethod decode(data)[source]¶

Decode DeviceCommunicationControl-Request from service request bytes.

Parameters:: data (memoryview | bytes) – Raw service request bytes.
Return type:: DeviceCommunicationControlRequest
Returns:: Decoded DeviceCommunicationControlRequest.
Raises:: BACnetRejectError – If a parameter is out of range.

class bac_py.services.device_mgmt.ReinitializeDeviceRequest(reinitialized_state, password=None)[source]¶

Bases: object

ReinitializeDevice-Request (Clause 16.4.1).

ReinitializeDevice-Request ::= SEQUENCE {
    reinitializedStateOfDevice  [0] ENUMERATED,
    password                    [1] CharacterString (1..20) OPTIONAL
}

Parameters:

reinitialized_state (ReinitializedState)
password (str | None)

reinitialized_state: ReinitializedState¶

password: str | None¶

encode()[source]¶

Encode ReinitializeDevice-Request service parameters.

Return type:: bytes
Returns:: Encoded service request bytes.

classmethod decode(data)[source]¶

Decode ReinitializeDevice-Request from service request bytes.

Parameters:: data (memoryview | bytes) – Raw service request bytes.
Return type:: ReinitializeDeviceRequest
Returns:: Decoded ReinitializeDeviceRequest.
Raises:: BACnetRejectError – If the password is out of range.

class bac_py.services.device_mgmt.TimeSynchronizationRequest(date, time)[source]¶

Bases: object

TimeSynchronization-Request (Clause 16.7.1).

TimeSynchronization-Request ::= SEQUENCE {
    date  Date,
    time  Time
}

Both fields are APPLICATION-tagged (not context).

Parameters:

date (BACnetDate)
time (BACnetTime)

date: BACnetDate¶

time: BACnetTime¶

encode()[source]¶

Encode TimeSynchronization-Request service parameters.

Return type:: bytes
Returns:: Encoded service request bytes.

classmethod decode(data)[source]¶

Decode TimeSynchronization-Request from service request bytes.

Parameters:: data (memoryview | bytes) – Raw service request bytes.
Return type:: Self
Returns:: Decoded request instance.

class bac_py.services.device_mgmt.UTCTimeSynchronizationRequest(date, time)[source]¶

Bases: TimeSynchronizationRequest

UTCTimeSynchronization-Request (Clause 16.8.1).

Same structure as TimeSynchronizationRequest but uses UnconfirmedServiceChoice.UTC_TIME_SYNCHRONIZATION (9).

Parameters:

date (BACnetDate)
time (BACnetTime)

Object Management¶

Object management services per ASHRAE 135-2016 Clause 15.3-15.4.

CreateObject (Clause 15.3), DeleteObject (Clause 15.4).

class bac_py.services.object_mgmt.CreateObjectRequest(object_type=None, object_identifier=None, list_of_initial_values=None)[source]¶

Bases: object

CreateObject-Request (Clause 15.3.1.1).

CreateObject-Request ::= SEQUENCE {
    objectSpecifier  [0] CHOICE {
        objectType        [0] BACnetObjectType,
        objectIdentifier  [1] BACnetObjectIdentifier
    },
    listOfInitialValues  [1] SEQUENCE OF BACnetPropertyValue OPTIONAL
}

Parameters:

object_type (ObjectType | None)
object_identifier (ObjectIdentifier | None)
list_of_initial_values (list[BACnetPropertyValue] | None)

object_type: ObjectType | None¶

object_identifier: ObjectIdentifier | None¶

list_of_initial_values: list[BACnetPropertyValue] | None¶

encode()[source]¶

Encode CreateObject-Request service parameters.

Return type:: bytes
Returns:: Encoded service request bytes.

classmethod decode(data)[source]¶

Decode CreateObject-Request from service request bytes.

Parameters:: data (memoryview | bytes) – Raw service request bytes.
Return type:: CreateObjectRequest
Returns:: Decoded CreateObjectRequest.
Raises:: ValueError – If the objectSpecifier CHOICE tag is unrecognized.

class bac_py.services.object_mgmt.DeleteObjectRequest(object_identifier)[source]¶

Bases: object

DeleteObject-Request (Clause 15.4.1.1).

DeleteObject-Request ::= SEQUENCE {
    objectIdentifier  BACnetObjectIdentifier
}

The objectIdentifier is APPLICATION-tagged.

Parameters:: object_identifier (ObjectIdentifier)

object_identifier: ObjectIdentifier¶

encode()[source]¶

Encode DeleteObject-Request service parameters.

Return type:: bytes
Returns:: Encoded service request bytes.

classmethod decode(data)[source]¶

Decode DeleteObject-Request from service request bytes.

Parameters:: data (memoryview | bytes) – Raw service request bytes.
Return type:: DeleteObjectRequest
Returns:: Decoded DeleteObjectRequest.

List Element¶

List element services per ASHRAE 135-2016 Clause 15.1-15.2.

AddListElement (Clause 15.1), RemoveListElement (Clause 15.2).

class bac_py.services.list_element.AddListElementRequest(object_identifier, property_identifier, list_of_elements, property_array_index=None)[source]¶

Bases: _ListElementRequest

AddListElement-Request (Clause 15.1.1.1).

Parameters:

object_identifier (ObjectIdentifier)
property_identifier (PropertyIdentifier)
list_of_elements (bytes)
property_array_index (int | None)

class bac_py.services.list_element.RemoveListElementRequest(object_identifier, property_identifier, list_of_elements, property_array_index=None)[source]¶

Bases: _ListElementRequest

RemoveListElement-Request (Clause 15.2.1.1).

Parameters:

object_identifier (ObjectIdentifier)
property_identifier (PropertyIdentifier)
list_of_elements (bytes)
property_array_index (int | None)

File Access¶

Atomic file access services per ASHRAE 135-2016 Clause 14.

AtomicReadFile (Clause 14.1), AtomicWriteFile (Clause 14.2).

class bac_py.services.file_access.StreamReadAccess(file_start_position, requested_octet_count)[source]¶

Bases: object

Stream access parameters for AtomicReadFile-Request.

Parameters:

file_start_position (int)
requested_octet_count (int)

file_start_position: int¶

requested_octet_count: int¶

class bac_py.services.file_access.RecordReadAccess(file_start_record, requested_record_count)[source]¶

Bases: object

Record access parameters for AtomicReadFile-Request.

Parameters:

file_start_record (int)
requested_record_count (int)

file_start_record: int¶

requested_record_count: int¶

class bac_py.services.file_access.AtomicReadFileRequest(file_identifier, access_method)[source]¶

Bases: object

AtomicReadFile-Request (Clause 14.1.1.1).

AtomicReadFile-Request ::= SEQUENCE {
    fileIdentifier    BACnetObjectIdentifier,
    accessMethod      CHOICE {
        streamAccess  [0] SEQUENCE {
            fileStartPosition      INTEGER,
            requestedOctetCount    Unsigned
        },
        recordAccess  [1] SEQUENCE {
            fileStartRecord        INTEGER,
            requestedRecordCount   Unsigned
        }
    }
}

Parameters:

file_identifier (ObjectIdentifier)
access_method (StreamReadAccess | RecordReadAccess)

file_identifier: ObjectIdentifier¶

access_method: StreamReadAccess | RecordReadAccess¶

encode()[source]¶

Encode AtomicReadFile-Request service parameters.

Return type:: bytes
Returns:: Encoded service request bytes.

classmethod decode(data)[source]¶

Decode AtomicReadFile-Request from service request bytes.

Parameters:: data (memoryview | bytes) – Raw service request bytes.
Return type:: AtomicReadFileRequest
Returns:: Decoded AtomicReadFileRequest.
Raises:: ValueError – If the access method CHOICE tag is unrecognized.

class bac_py.services.file_access.StreamReadACK(file_start_position, file_data)[source]¶

Bases: object

Stream access result for AtomicReadFile-ACK.

Parameters:

file_start_position (int)
file_data (bytes)

file_start_position: int¶

file_data: bytes¶

class bac_py.services.file_access.RecordReadACK(file_start_record, returned_record_count, file_record_data)[source]¶

Bases: object

Record access result for AtomicReadFile-ACK.

Parameters:

file_start_record (int)
returned_record_count (int)
file_record_data (list[bytes])

file_start_record: int¶

returned_record_count: int¶

file_record_data: list[bytes]¶

class bac_py.services.file_access.AtomicReadFileACK(end_of_file, access_method)[source]¶

Bases: object

AtomicReadFile-ACK (Clause 14.1.1.2).

AtomicReadFile-ACK ::= SEQUENCE {
    endOfFile       BOOLEAN,
    accessMethod    CHOICE {
        streamAccess  [0] SEQUENCE {
            fileStartPosition  INTEGER,
            fileData           OCTET STRING
        },
        recordAccess  [1] SEQUENCE {
            fileStartRecord      INTEGER,
            returnedRecordCount  Unsigned,
            fileRecordData       SEQUENCE OF OCTET STRING
        }
    }
}

Parameters:

end_of_file (bool)
access_method (StreamReadACK | RecordReadACK)

end_of_file: bool¶

access_method: StreamReadACK | RecordReadACK¶

encode()[source]¶

Encode AtomicReadFile-ACK service parameters.

Return type:: bytes
Returns:: Encoded service ACK bytes.

classmethod decode(data)[source]¶

Decode AtomicReadFile-ACK from service ACK bytes.

Parameters:: data (memoryview | bytes) – Raw service ACK bytes.
Return type:: AtomicReadFileACK
Returns:: Decoded AtomicReadFileACK.
Raises:: ValueError – If the access method CHOICE tag is unrecognized.

class bac_py.services.file_access.StreamWriteAccess(file_start_position, file_data)[source]¶

Bases: object

Stream access parameters for AtomicWriteFile-Request.

Parameters:

file_start_position (int)
file_data (bytes)

file_start_position: int¶

file_data: bytes¶

class bac_py.services.file_access.RecordWriteAccess(file_start_record, record_count, file_record_data)[source]¶

Bases: object

Record access parameters for AtomicWriteFile-Request.

Parameters:

file_start_record (int)
record_count (int)
file_record_data (list[bytes])

file_start_record: int¶

record_count: int¶

file_record_data: list[bytes]¶

class bac_py.services.file_access.AtomicWriteFileRequest(file_identifier, access_method)[source]¶

Bases: object

AtomicWriteFile-Request (Clause 14.2.1.1).

AtomicWriteFile-Request ::= SEQUENCE {
    fileIdentifier    BACnetObjectIdentifier,
    accessMethod      CHOICE {
        streamAccess  [0] SEQUENCE {
            fileStartPosition  INTEGER,
            fileData           OCTET STRING
        },
        recordAccess  [1] SEQUENCE {
            fileStartRecord    INTEGER,
            recordCount        Unsigned,
            fileRecordData     SEQUENCE OF OCTET STRING
        }
    }
}

Parameters:

file_identifier (ObjectIdentifier)
access_method (StreamWriteAccess | RecordWriteAccess)

file_identifier: ObjectIdentifier¶

access_method: StreamWriteAccess | RecordWriteAccess¶

encode()[source]¶

Encode AtomicWriteFile-Request service parameters.

Return type:: bytes
Returns:: Encoded service request bytes.

classmethod decode(data)[source]¶

Decode AtomicWriteFile-Request from service request bytes.

Parameters:: data (memoryview | bytes) – Raw service request bytes.
Return type:: AtomicWriteFileRequest
Returns:: Decoded AtomicWriteFileRequest.
Raises:: ValueError – If the access method CHOICE tag is unrecognized.

class bac_py.services.file_access.AtomicWriteFileACK(is_stream, file_start)[source]¶

Bases: object

AtomicWriteFile-ACK (Clause 14.2.1.2).

AtomicWriteFile-ACK ::= CHOICE {
    fileStartPosition  [0] INTEGER,
    fileStartRecord    [1] INTEGER
}

Parameters:

is_stream (bool)
file_start (int)

is_stream: bool¶

file_start: int¶

encode()[source]¶

Encode AtomicWriteFile-ACK service parameters.

Return type:: bytes
Returns:: Encoded service ACK bytes.

classmethod decode(data)[source]¶

Decode AtomicWriteFile-ACK from service ACK bytes.

Parameters:: data (memoryview | bytes) – Raw service ACK bytes.
Return type:: AtomicWriteFileACK
Returns:: Decoded AtomicWriteFileACK.

Private Transfer¶

Private transfer services per ASHRAE 135-2016 Clause 16.2-16.3.

ConfirmedPrivateTransfer (Clause 16.2), UnconfirmedPrivateTransfer (Clause 16.3).

class bac_py.services.private_transfer.ConfirmedPrivateTransferRequest(vendor_id, service_number, service_parameters=None)[source]¶

Bases: object

ConfirmedPrivateTransfer-Request (Clause 16.2.1.1).

ConfirmedPrivateTransfer-Request ::= SEQUENCE {
    vendorID          [0] Unsigned,
    serviceNumber     [1] Unsigned,
    serviceParameters [2] ABSTRACT-SYNTAX.&TYPE OPTIONAL
}

Parameters:

vendor_id (int)
service_number (int)
service_parameters (bytes | None)

vendor_id: int¶

service_number: int¶

service_parameters: bytes | None¶

encode()[source]¶

Encode ConfirmedPrivateTransfer-Request service parameters.

Return type:: bytes
Returns:: Encoded service request bytes.

classmethod decode(data)[source]¶

Decode ConfirmedPrivateTransfer-Request from service request bytes.

Parameters:: data (memoryview | bytes) – Raw service request bytes.
Return type:: Self
Returns:: Decoded request instance.

class bac_py.services.private_transfer.ConfirmedPrivateTransferACK(vendor_id, service_number, result_block=None)[source]¶

Bases: object

ConfirmedPrivateTransfer-ACK (Clause 16.2.1.2).

Uses the same wire format as the request, but the context-2 tagged block carries vendor-defined result data rather than request service-parameters.

Parameters:

vendor_id (int)
service_number (int)
result_block (bytes | None)

vendor_id: int¶

service_number: int¶

result_block: bytes | None¶

encode()[source]¶

Encode ConfirmedPrivateTransfer-ACK service parameters.

Return type:: bytes
Returns:: Encoded service ACK bytes.

classmethod decode(data)[source]¶

Decode ConfirmedPrivateTransfer-ACK from service ACK bytes.

Parameters:: data (memoryview | bytes) – Raw service ACK bytes.
Return type:: ConfirmedPrivateTransferACK
Returns:: Decoded ConfirmedPrivateTransferACK.

class bac_py.services.private_transfer.UnconfirmedPrivateTransferRequest(vendor_id, service_number, service_parameters=None)[source]¶

Bases: ConfirmedPrivateTransferRequest

UnconfirmedPrivateTransfer-Request (Clause 16.3.1.1).

Same structure as ConfirmedPrivateTransfer-Request.

Parameters:

vendor_id (int)
service_number (int)
service_parameters (bytes | None)

Virtual Terminal¶

Virtual terminal services per ASHRAE 135-2020 Clause 17.

VT-Open (Clause 17.1), VT-Close (Clause 17.2), VT-Data (Clause 17.3).

class bac_py.services.virtual_terminal.VTOpenRequest(vt_class, local_vt_session_identifier)[source]¶

Bases: object

VT-Open-Request (Clause 17.1.1).

VT-Open-Request ::= SEQUENCE {
    vtClass                    BACnetVTClass,
    localVTSessionIdentifier   Unsigned8
}

Parameters:

vt_class (VTClass)
local_vt_session_identifier (int)

vt_class: VTClass¶

local_vt_session_identifier: int¶

encode()[source]¶

Encode VT-Open-Request service parameters.

Return type:: bytes

classmethod decode(data)[source]¶

Decode VT-Open-Request from service request bytes.

Return type:: VTOpenRequest
Parameters:: data (memoryview | bytes)

class bac_py.services.virtual_terminal.VTOpenACK(remote_vt_session_identifier)[source]¶

Bases: object

VT-Open-ACK (Clause 17.1.2).

VT-Open-ACK ::= SEQUENCE {
    remoteVTSessionIdentifier  Unsigned8
}

Parameters:: remote_vt_session_identifier (int)

remote_vt_session_identifier: int¶

encode()[source]¶

Encode VT-Open-ACK service parameters.

Return type:: bytes

classmethod decode(data)[source]¶

Decode VT-Open-ACK from service request bytes.

Return type:: VTOpenACK
Parameters:: data (memoryview | bytes)

class bac_py.services.virtual_terminal.VTCloseRequest(list_of_remote_vt_session_identifiers)[source]¶

Bases: object

VT-Close-Request (Clause 17.2.1).

VT-Close-Request ::= SEQUENCE {
    listOfRemoteVTSessionIdentifiers  SEQUENCE OF Unsigned8
}

Parameters:: list_of_remote_vt_session_identifiers (list[int])

list_of_remote_vt_session_identifiers: list[int]¶

encode()[source]¶

Encode VT-Close-Request service parameters.

Return type:: bytes

classmethod decode(data)[source]¶

Decode VT-Close-Request from service request bytes.

Return type:: VTCloseRequest
Parameters:: data (memoryview | bytes)

class bac_py.services.virtual_terminal.VTDataRequest(vt_session_identifier, vt_new_data, vt_data_flag)[source]¶

Bases: object

VT-Data-Request (Clause 17.3.1).

VT-Data-Request ::= SEQUENCE {
    vtSessionIdentifier  Unsigned8,
    vtNewData            OCTET STRING,
    vtDataFlag           BOOLEAN
}

Parameters:

vt_session_identifier (int)
vt_new_data (bytes)
vt_data_flag (bool)

vt_session_identifier: int¶

vt_new_data: bytes¶

vt_data_flag: bool¶

encode()[source]¶

Encode VT-Data-Request service parameters.

Return type:: bytes

classmethod decode(data)[source]¶

Decode VT-Data-Request from service request bytes.

Return type:: VTDataRequest
Parameters:: data (memoryview | bytes)

class bac_py.services.virtual_terminal.VTDataACK(all_new_data_accepted, accepted_octet_count=None)[source]¶

Bases: object

VT-Data-ACK (Clause 17.3.2).

VT-Data-ACK ::= SEQUENCE {
    allNewDataAccepted  BOOLEAN,
    acceptedOctetCount  Unsigned OPTIONAL
}

accepted_octet_count is present only when all_new_data_accepted is False.

Parameters:

all_new_data_accepted (bool)
accepted_octet_count (int | None)

all_new_data_accepted: bool¶

accepted_octet_count: int | None¶

encode()[source]¶

Encode VT-Data-ACK service parameters.

Return type:: bytes

classmethod decode(data)[source]¶

Decode VT-Data-ACK from service request bytes.

Return type:: VTDataACK
Parameters:: data (memoryview | bytes)

Write Group¶

WriteGroup service per ASHRAE 135-2020 Clause 15.11.

WriteGroup is an unconfirmed service for writing channel values via group addressing.

class bac_py.services.write_group.GroupChannelValue(channel, value, overriding_priority=None)[source]¶

Bases: object

A single channel value in a WriteGroup change list.

GroupChannelValue ::= SEQUENCE {
    channel             [0] Unsigned16,
    overridingPriority  [1] Unsigned (1..16) OPTIONAL,
    value               ABSTRACT-SYNTAX.&TYPE
}

Parameters:

channel (int)
value (bytes)
overriding_priority (int | None)

channel: int¶

value: bytes¶

overriding_priority: int | None¶

encode()[source]¶

Encode a single GroupChannelValue.

Return type:: bytes

classmethod decode(data, offset)[source]¶

Decode a single GroupChannelValue starting at offset.

Return type:

tuple[GroupChannelValue, int]

Returns:

Tuple of (decoded value, new offset).

Parameters:

data (memoryview)
offset (int)

class bac_py.services.write_group.WriteGroupRequest(group_number, write_priority, change_list)[source]¶

Bases: object

WriteGroup-Request (Clause 15.11.1).

WriteGroup-Request ::= SEQUENCE {
    groupNumber    [0] Unsigned32,
    writePriority  [1] Unsigned (1..16),
    changeList     [2] SEQUENCE OF GroupChannelValue
}

Parameters:

group_number (int)
write_priority (int)
change_list (list[GroupChannelValue])

group_number: int¶

write_priority: int¶

change_list: list[GroupChannelValue]¶

encode()[source]¶

Encode WriteGroup-Request service parameters.

Return type:: bytes

classmethod decode(data)[source]¶

Decode WriteGroup-Request from service request bytes.

Return type:: Self
Parameters:: data (memoryview | bytes)