This README is the one indexed from the repository at its latest ref, not from the tag for this version.

Crystal KNX

Constructs KNX standard datagrams that make it easy to communicate with devices on KNX networks.

Usage

require "knx"

knx = KNX.new
datagram = knx.read(bytes)
datagram.source_address.to_s
# => "2.3.4"

datagram.destination_address.to_s
# => "3/4/5"

datagram.data # Returns a byte array
# => [1]

# ...

request = knx.action("1/2/0", true)
bytes = request.to_slice

request = knx.action("1/2/3", 150)
bytes = request.to_slice

# Send byte_string to KNX network to execute the request
# Supports multicast, unicast and TCP/IP tunnelling

There is also support for KNX BAOS devices devices:

require "knx/object_server"

os = KNX::ObjectServer.new
datagram = os.read(bytes)

# Can return multiple values
datagram.data.size #=> 1

# Get the item index we are reading
datagram.data[0].id
# => 12

datagram.data[0].value # Returns bytes
# => Bytes[1]

# ...

request = os.action(1, true)
bytes = request.to_slice

# Send byte_string to KNX BAOS server to execute the request
# This protocol was designed to be sent over TCP/IP

and support for Tunnelling

require "knx/tunnel_client"

# connect to the interface
interface_ip = Socket::IPAddress.new("192.168.0.10", 3671)
udp_socket = UDPSocket.new
udp_socket.connect interface_ip.address, interface_ip.port

# determine our local IP address
local_ip = udp_socket.local_address

# configure the client
client = KNX::TunnelClient.new(control_ip)

is_connected = false
client.on_state_change do |connected, error|
  # we should maintain the connection
  if connected
    spawn do
      loop do
        break unless is_connected
        sleep 60.seconds
        # sends a connection state request
        client.query_state
      end
    end
  end
end

# send the data down the transport
client.on_transmit { |bytes| udp_socket.write bytes }

# we received a tunnelled request from the interface (forwarded broadcast packets)
client.on_message do |cemi|
  cemi.destination_address # => 1/2/55
  cemi.data # => Bytes (can process data based on the address)
end

# process any incoming data on the socket
spawn do
  message = Bytes.new(512)
  loop do
    bytes_read, client_addr = udp_socket.receive(message)
    client.process(message[0, bytes_read])
  end
end

# send any messages
client.status("1/2/55")

client.action("1/2/55", true)
client.action("2/2/55", 3)
client.action("1/3/55", 8.4)

License

MIT