ait.dsn.sle.frames module

class ait.dsn.sle.frames.AOSConfig(*args, **kwargs)

Bases: object

AOS frame configuration class.

This configuration contains information regarding the inclusion of optional AOS frame fields and a dictionary of virtual channel values to AOS data frame types.

get_data_field_indices()

Returns the slice-indices for the data field in AOS frame :return: Data field indices

get_data_field_type(vc_number)

Returns the data field type associated with a virtual

channel id. If the virtual channel id is undeclared, then None is returned.

Parameters

vc_number – THe virtual channel id number (int)

Returns

AOSDataFieldType enum value associated with virtual channel id

get_frame_error_control_field_indices()

Returns the slice-indices for the frame error control field if defined, otherwise None is returned :return: Frame error control field indices or None

get_frame_header_error_control_indices()

Returns the slice-indices for the Frame header control field if defined, otherwise None is returned :return: Frame header error control field indices or None

get_operational_control_field_indices()

Returns the slice-indices for the operational control field if defined, otherwise None is returned :return: Operation control field indices or None

get_transfer_frame_insert_zone_indices()

Returns the slice-indices for the transfer frame insert zone if defined, otherwise None is returned :return: Transfer frame insert zone indices or None

get_virtual_channel_count()

Returns the size of the virtual channel data field type map :return: size of virtual-channel data-field-type map

property transfer_frame_insert_zone_included

Returns true if Transfer Frame Insert Zone field is defined in AOS Frame, false otherwise :return: Flag indicating Transfer Frame Insert Zone field existence

class ait.dsn.sle.frames.AOSDataFieldType(value)

Bases: Enum

Enumeration for AOS Data Field types

B_PDU = 'B_PDU'

IDLE = 'IDLE'

M_PDU = 'M_PDU'

VCA_SDU = 'VCA_SDU'

class ait.dsn.sle.frames.AOSTransFrame(data=None, config=None)

Bases: BaseTransferFrame

Implementation of the AOS transfer frame.

The AOSTransFrame class decodes data packets to extract information from header, data-field, and trailer. An instance of AOSConfig guides the process by indicating which optional fields are included, as well as determining the type of the datafield via the virtual channel id.

decode(data)

Decode data as a AOS Transfer Frame

decode_dataField_BPDU(datafield)

Decodes the B_PDU datafield

Parameters

datafield – AOS datafield to be decoded

decode_dataField_Idle(datafield)

Decodes the IDLE datafield

Parameters

datafield – AOS datafield to be decoded

decode_dataField_MPDU(datafield)

Decodes the M_PDU datafield

Parameters

datafield – AOS datafield to be decoded

decode_dataField_VCASDU(datafield)

Decodes the VCA_SDU datafield

Parameters

datafield – AOS datafield to be decoded

decode_data_field(datafield)

Decode the data-field section of the data, using the virtual channel id which indicates that data field type

Parameters

datafield – Data-field section of the AOS frame

defaultConfig = <ait.dsn.sle.frames.AOSConfig object>

encode()

class ait.dsn.sle.frames.BaseTransferFrame(data=None)

Bases: dict

Transfer Frame interface “base” class

The BaseTransformFrame class provides Transfer Frame interface-agnostic methods and attributes for interfacing with Frames.

contains_data()

Returns True if frame contains data, False otherwise

Returns:

Boolean value indicating if frame contains data

property data_field

Returns the data portion of the transfer frame.

Returns

The frame data portion, including potential inner-dataframe headers

property is_idle_frame

Returns True if this frame is an Idle frame, as indicated by

the special Idle virtual channel ID, False otherwise. (Note: This is different from an M_PDU Idle data-field section)

Returns:

Boolean value indicating if this is an IDLE frame.

property master_channel_id

Returns Master Channel ID (integer)

property virtual_channel

Returns Virtual Channel ID (integer)

class ait.dsn.sle.frames.TMTransFrame(data=None)

Bases: BaseTransferFrame

decode(data)

Decode data as a TM Transfer Frame

encode()