BACnet Support for Crystal Lang

it supports

• the IPv4 data link layer (BACnet/IP)
• the websocket data link layer (BACnet/SC)

Installation

Add the dependency to your shard.yml:

dependencies:
  bacnet:
    github: spider-gazelle/crystal-bacnet

Usage

Currently this implements the code required to parse and generate BACnet messages. It does not implement a client.

require "bacnet"

message = io.read_bytes(BACnet::IP4Message)
message.data_link.request_type # => BACnet::RequestTypeIP4::OriginalUnicastNPDU

if network = message.network
  network.destination.address # => 26001
  network.expecting_reply? # => true
  network.hop_count # => 255

  app_layer = message.application
  case app_layer
  when BACnet::ConfirmedRequest
    app_layer.segmented_message
    app_layer.max_segments
  when BACnet::ComplexAck
  # ...
  end

  # Objects associated with the request
  message.objects # => [] of BACnet::Object

  # Helpers for primitive objects exist, constructed objects require request context
  message.objects.each do |object|
    puts object.value unless object.context_specific
  end
end