public static KnxCEMI FromBytes(bool threeLevelGroupAssigning, byte[] cemiBytes)
{
var cemi = new KnxCEMI();
cemi.message_code = cemiBytes[0];
cemi.aditional_info_length = cemiBytes[1];
if (cemi.aditional_info_length > 0)
{
cemi.aditional_info = new byte[cemi.aditional_info_length];
Array.Copy(cemiBytes, 2, cemi.aditional_info, 0, cemi.aditional_info_length);
}
cemi.control_field_1 = cemiBytes[2 + cemi.aditional_info_length];
cemi.control_field_2 = cemiBytes[3 + cemi.aditional_info_length];
cemi.source_address = KnxHelper.GetIndividualAddress(new[] { cemiBytes[4 + cemi.aditional_info_length], cemiBytes[5 + cemi.aditional_info_length] });
cemi.destination_address =
KnxHelper.GetKnxDestinationAddressType(cemi.control_field_2).Equals(KnxHelper.KnxDestinationAddressType.INDIVIDUAL)
? KnxHelper.GetIndividualAddress(new[] { cemiBytes[6 + cemi.aditional_info_length], cemiBytes[7 + cemi.aditional_info_length] })
: KnxHelper.GetGroupAddress(new[] { cemiBytes[6 + cemi.aditional_info_length], cemiBytes[7 + cemi.aditional_info_length] }, threeLevelGroupAssigning);
var data_length = Math.Min(cemiBytes[8 + cemi.aditional_info_length], cemiBytes.Length - 10); // AR
if (data_length > 0)
{
cemi.apdu = new byte[data_length];
Array.Copy(cemiBytes, 10 + cemi.aditional_info_length, cemi.apdu, 0, data_length);
}
return(cemi);
}
/// <summary>
/// Send a byte array value as data to specified address
/// </summary>
/// <param name="address">KNX Address</param>
/// <param name="data">Byte array value</param>
public async void Action(string address, string type, object value)
{
byte[] asdu = DataPointTranslator.Instance.ToASDU(type, value);
var cemi = KnxCEMI.CreateActionCEMI(_messageCode, address, asdu);
var cemiBytes = cemi.ToBytes();
// header
var header = new byte[10];
header[00] = 0x06; /* 06 - Header Length */
header[01] = 0x10; /* 10 - KNXnet version (1.0) */
header[02] = 0x04; /* 04 - hi-byte Service type descriptor (TUNNELLING_REQUEST) */
header[03] = 0x20; /* 20 - lo-byte Service type descriptor (TUNNELLING_REQUEST) */
var totalLength = BitConverter.GetBytes(header.Length + cemiBytes.Length);
header[04] = totalLength[1];
header[05] = totalLength[0];
/* Connection Header (4 Bytes) */
header[06] = 0x04; /* 04 - Structure length */
header[07] = _channelId;
header[08] = _sequenceNo++;
header[09] = 0x00; /* 00 - Reserved */
var datagram = new byte[header.Length + cemiBytes.Length];
Array.Copy(header, datagram, header.Length);
Array.Copy(cemiBytes, 0, datagram, header.Length, cemiBytes.Length);
await _udpClient?.Send(datagram);
}
private void ProcessDatagramHeaders(byte[] datagram)
{
// HEADER
// TODO: Might be interesting to take out these magic numbers for the datagram indices
var knxDatagram = new KnxNetTunnelingDatagram
{
header_length = datagram[0],
protocol_version = datagram[1],
service_type = (ushort)((datagram[2] << 8) + datagram[3]),
total_length = datagram[4] + datagram[5]
};
var channelId = datagram[7];
if (channelId != _channelId)
{
return;
}
var sequenceNumber = datagram[8];
var process = sequenceNumber > _rxSequenceNo;
_rxSequenceNo = sequenceNumber;
if (process)
{
// TODO: Magic number 10, what is it?
var cemiBytes = new byte[datagram.Length - 10];
Array.Copy(datagram, 10, cemiBytes, 0, datagram.Length - 10);
var knxCEMI = KnxCEMI.FromBytes(_threeLevelGroupAssigning, cemiBytes);
if (knxCEMI.IsEvent)
{
Debug.WriteLine("KNX Event " + knxCEMI.destination_address + " " + BitConverter.ToString(knxCEMI.apdu));
this.KnxEvent?.Invoke(this, new KnxEventArgs()
{
Address = knxCEMI.destination_address,
Data = knxCEMI.apdu
});
}
else if (knxCEMI.IsStatus)
{
Debug.WriteLine("KNX Status " + knxCEMI.destination_address + " " + BitConverter.ToString(knxCEMI.apdu));
this.KnxStatus?.Invoke(this, new KnxEventArgs()
{
Address = knxCEMI.destination_address,
Data = knxCEMI.apdu
});
}
}
this.SendTunnelingAck(sequenceNumber);
}
public static KnxCEMI CreateStatusCEMI(byte messageCode, string destinationAddress)
{
KnxCEMI cemi = new KnxCEMI()
{
message_code = messageCode != 0x00 ? messageCode : (byte)0x11,
aditional_info_length = 0,
control_field_1 = 0xAC,
control_field_2 = KnxHelper.IsAddressIndividual(destinationAddress) ? (byte)0x50 : (byte)0xF0,
destination_address = destinationAddress,
apdu = new byte[] { 0x00 },
_isstatus = true
};
return(cemi);
}
public static KnxCEMI CreateActionCEMI(byte messageCode, string destinationAddress, byte[] asdu)
{
KnxCEMI cemi = new KnxCEMI()
{
message_code = messageCode != 0x00 ? messageCode : (byte)0x11,
aditional_info_length = 0,
control_field_1 = 0xAC,
control_field_2 = KnxHelper.IsAddressIndividual(destinationAddress) ? (byte)0x50 : (byte)0xF0,
destination_address = destinationAddress,
apdu = new byte[asdu.Length]
};
cemi.apdu[0] = (byte)(0x80 | (asdu[0] & 0x3f));
for (var i = 1; i < asdu.Length; i++)
{
cemi.apdu[i] = asdu[i];
}
return(cemi);
}