private void EstablishConnection()
{
if (_oldConnected)
{
ConnectionChanged?.Invoke(_connectionContext, false);
_oldConnected = false;
}
if (_pollDevice == null)
{
Thread.Sleep(FailureRetryInterval);
_pollDevice = _master.ConnectDevice(_address, _port, _id);
return;
}
if (_pollDevice.IsConnected)
{
_retryCount = 0;
_failureCount = 0;
GoState(Connected);
return;
}
Thread.Sleep(FailureRetryInterval);
_failureCount++;
if (_failureCount > 2)
{
GoState(Disconnected);
}
}
/// <summary>
/// Start polling the specified slave.
/// Establish connection.
/// </summary>
/// <param name="master"></param>
/// <param name="address"></param>
/// <param name="port"></param>
/// <param name="id"></param>
/// <param name="register"></param>
/// <param name="offset"></param>
/// <param name="count"></param>
public ModbusDevicePollService(ModbusMaster master, string address, ushort port, byte id, Register register, int offset, int count)
{
_master = master;
_address = address;
_port = port;
_id = id;
_pollDevice = null;
_oldConnected = true;
_registerToPoll = register;
_pollOffset = offset;
_pollCount = count;
_traceId = $"ModbusDevicePollService({address}:{port}#{id})";
PollRetryInterval = TimeSpan.FromSeconds(0.1);
FailureRetryInterval = TimeSpan.FromSeconds(1);
PollRetries = 1;
}
public void Stop()
{
if (_pollingTask == null)
{
return;
}
var p = _pollingTask;
_pollingTask = null;
p?.Wait(TimeSpan.FromSeconds(10));
if (_pollDevice != null)
{
_pollDevice.Disconnect();
_pollDevice.Dispose();
_pollDevice = null;
}
}
public ConnectedSlave ConnectDevice(string address, ushort port, byte id)
{
var sock = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.IP);
try
{
sock.Connect(address, port);
if (!sock.Connected)
{
LastError = "Connect failed";
sock.Dispose();
return(null);
}
}
catch (Exception ex)
{
LastError = ex.Message;
Trace.TraceError("ModbusMaster: Could not connect to {0}:{1} id={2}" + Environment.NewLine + ex.Message,
address, port, id);
sock.Dispose();
return(null);
}
LastError = null;
var dev = new ConnectedSlave(this, sock, id);
dev.Disconnected += () =>
{
lock (ConnectedSlaveDevices)
{
ConnectedSlaveDevices.Remove(dev);
}
};
lock (ConnectedSlaveDevices)
{
ConnectedSlaveDevices.Add(dev);
}
Trace.TraceInformation("ModbusMaster: Connected to device {0}:{1} id={2}", address, port, id);
return(dev);
}
/// <summary>
/// Start polling already connected slave.
/// </summary>
/// <param name="slave"></param>
/// <param name="register"></param>
/// <param name="offset"></param>
/// <param name="count"></param>
public ModbusDevicePollService(ConnectedSlave slave, Register register, int offset, int count)
: this(slave.Master, slave.Address.ToString(), slave.Port, slave.Id, register, offset, count)
{
_pollDevice = slave;
_oldConnected = !_pollDevice.IsConnected;
}