BACnet.Protocol (bacstack v0.0.1)

This module is mostly used for basic decoding of BACnet frames (Protocol Data Units - PDU).

This module handles decoding of BVLL (and delegates specifics), NPCI and NSDU. APDU is completely covered by BACnet.Protocol.APDU.

For BACnet Virtual Link Layer (BVLL), it will handle it and delegate, once it determines it is a BVLC function. BVLC function codes such as distribute broadcast, original broad- and unicast and forwarded NPDU are handled by this module directly. Currently only BVLL type 0x81 (BACnet/IPv4) is implemented.

For Network Protocol Control Information (NPCI), it will handle all decoding associated with it and handle field handling.

For Network Service Data Unit (NSDU), it will handle all decoding associated with the regular BACnet types, excluding reserved and vendor proprietary.

For Application Data Unit (APDU), see the BACnet.Protocol.APDU module.

See also the following modules:

Summary

Types

apdu()

BACnet Application Data Units (APDU).

bvlc()

BACnet Virtual Link Control (BVLC), used in BACnet/IP.

Functions

decode_bvll(bvll_type, bvlc_function, data)

Decodes the BVLL header of a BACnet/IP packet.

decode_npci(data)

Decodes the NPCI header of a BACnet packet.

decode_npdu(npci, data)

Decodes the NPDU of a BACnet packet.

decode_nsdu(data)

Decodes the NSDU of a BACnet packet.

Types

apdu()

@type apdu() ::
  BACnet.Protocol.APDU.ConfirmedServiceRequest.t()
  | BACnet.Protocol.APDU.UnconfirmedServiceRequest.t()
  | BACnet.Protocol.APDU.ComplexACK.t()
  | BACnet.Protocol.APDU.SimpleACK.t()
  | BACnet.Protocol.APDU.SegmentACK.t()
  | BACnet.Protocol.APDU.Abort.t()
  | BACnet.Protocol.APDU.Error.t()
  | BACnet.Protocol.APDU.Reject.t()

BACnet Application Data Units (APDU).

bvlc()

@type bvlc() ::
  BACnet.Protocol.BvlcForwardedNPDU.t()
  | BACnet.Protocol.BvlcFunction.t()
  | BACnet.Protocol.BvlcResult.t()
  | :distribute_broadcast_to_network
  | :original_broadcast
  | :original_unicast

BACnet Virtual Link Control (BVLC), used in BACnet/IP.

Functions

decode_bvll(bvll_type, bvlc_function, data)

@spec decode_bvll(non_neg_integer(), non_neg_integer(), binary()) ::
  {:ok, {bvlc_size :: non_neg_integer(), bvlc :: bvlc(), rest :: binary()}}
  | {:error, term()}

Decodes the BVLL header of a BACnet/IP packet.

decode_npci(data)

@spec decode_npci(binary()) ::
  {:ok, {BACnet.Protocol.NPCI.t(), rest :: binary()}} | {:error, term()}

Decodes the NPCI header of a BACnet packet.

decode_npdu(npci, data)

@spec decode_npdu(BACnet.Protocol.NPCI.t(), binary()) ::
  {:ok,
   {type :: :network | :apdu,
    BACnet.Protocol.NetworkLayerProtocolMessage.t() | binary()}}
  | {:error, term()}

Decodes the NPDU of a BACnet packet.

For network messages, it decodes the NSDU. For application messages, it simply returns the APDU for further processing.

decode_nsdu(data)

@spec decode_nsdu(binary()) ::
  {:ok, BACnet.Protocol.NetworkLayerProtocolMessage.t()} | {:error, term()}

Decodes the NSDU of a BACnet packet.