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TCP / UDP Channels

Zeus exposes TCP and UDP transports as IChannel, so protocol and business code do not need to care whether the bytes came from a socket, serial port, or virtual channel.

TCP Client​

builder.AddTcpClient("plc", "192.168.1.10", 502);

Use the options overload for custom timeouts:

builder.AddTcpClient("plc", options =>
{
    options.Host = "192.168.1.10";
    options.Port = 502;
    options.ConnectTimeoutMilliseconds = 2000;
});

Port 502 is common for Modbus TCP. Other binary protocols can use the same channel and layer Custom Framing or a protocol package on top.

TCP Server​

AddTcpServer listens locally. It fits devices or lower-level controllers that connect to the host application.

builder.AddTcpServer("listener", localPort: 1502);

If localPort is 0, the OS assigns a temporary port:

var listener = (TcpServerChannel)app.Channels.Get("listener");
await app.StartAsync();
Console.WriteLine(listener.LocalEndPoint?.Port);

WriteAsync replies to the most recent client. Use BroadcastAsync to push to every connected client.

await listener.BroadcastAsync("SYNC"u8.ToArray());

UDP Client​

AddUdpClient sends to and receives from a fixed remote endpoint:

builder.AddUdpClient("sensor", "192.168.1.20", 1502);

Use options to bind a fixed local port:

builder.AddUdpClient("sensor", options =>
{
    options.Host = "192.168.1.20";
    options.Port = 1502;
    options.LocalPort = 1502;
});

UDP has no connection, delivery guarantee, ordering, or retransmission. Implement request timeouts and retries in the protocol layer when needed.

UDP Server​

builder.AddUdpServer("listener", localPort: 1502);

WriteAsync replies to the most recent remote endpoint. If no datagram has been received yet, Zeus cannot infer where to send the response.

JSON Examples​

{
  "channels": [
    { "name": "plc", "type": "tcp", "host": "192.168.1.10", "port": 502 },
    { "name": "listener", "type": "udp-server", "localAddress": "0.0.0.0", "localPort": 1502 }
  ]
}

If connection or send/receive fails, check the remote listener, firewall, and local port conflicts. During early development, replace the channel with Virtual Channel.