Packet.Agw 0.25.0

Packet.Agw

AGW (AGWPE / SV2AGW) client for talking to LinBPQ, direwolf, SoundModem, and XRouter.

Packet.Agw dials an AGW server over TCP, registers your callsign, and opens AX.25 connected-mode sessions — each exposed as a plain .NET Stream. AGW (SV2AGW's PE+ protocol) is the canonical interop interface for software AX.25 stacks, so this is the easy way to drive a packet TNC from C# without owning the radio layer yourself. Part of Packet.NET, a .NET amateur-radio / AX.25 packet stack.

Install

dotnet add package Packet.Agw

Quick start

Connect to an AGW server, register a callsign, open a connected-mode session, and read/write it like any other stream:

using System.Text;
using Packet.Agw;

// Dial the AGW listener (LinBPQ / direwolf / SoundModem default to port 8000).
await using var client = await AgwClient.ConnectAsync("127.0.0.1", port: 8000);

// Register the callsign the server should route inbound frames to.
await client.RegisterCallsignAsync("N0CALL");

// Open an AX.25 connected-mode session (sends SABM, awaits the connect-ack).
await using AgwSession session = await client.OpenSessionAsync(from: "N0CALL", to: "Q0PDN");

// AgwSession is a Stream: write bytes to send I-frames, read bytes from the remote.
await session.WriteAsync(Encoding.ASCII.GetBytes("ports\r"));

var buffer = new byte[256];
int n = await session.ReadAsync(buffer);          // 0 == remote disconnected (EOF)
Console.WriteLine(Encoding.ASCII.GetString(buffer, 0, n));

await session.DisconnectAsync();

Writes larger than the per-frame cap (~256 bytes) are split into multiple data frames automatically. The default PID is 0xF0 ("no layer 3"); set session.DefaultPid to override (e.g. 0xCF for NET/ROM L3). client.GetPortInfoAsync() returns the server's configured radio ports.

Key types

• AgwClient — connect-initiator over one TCP connection; ConnectAsync / FromStream, RegisterCallsignAsync, OpenSessionAsync, GetPortInfoAsync. Pumps a keepalive ping so idle servers (BPQ closes at ~20s) don't drop you.
• AgwSession — one connected-mode session as a Stream; Read/Write, DefaultPid, DisconnectAsync, DisconnectedTask.
• AgwFrame — one frame on the wire (36-byte header + body); ToBytes, Parse, TryReadDataLength.
• AgwFrameStream — low-level frame I/O over any duplex byte Stream; use it directly for raw frame access.
• AgwCommandKind — the AGW command-kind ASCII letters (C connect, D data, d disconnect, X register, G port-info, ...).

See also

• Source & issues
• Packet.Ax25 — the AX.25 frame + session layer
• Packet.Kiss — the KISS-TNC alternative when you own the radio layer

AGPL-3.0-licensed. Part of the Packet.NET stack.