M0LTE.Rig 0.2.1

M0LTE.Rig

Two abstractions over an amateur-radio transceiver, both dependency-free and capability-probed: IRigControl, the station-control (CAT) seam, and IRadioControl, the channel-sensing seam. Pick IRigControl for anything an operator drives (a logger, a digimode app); pick IRadioControl for anything that reacts to channel activity (a MAC layer, a CSMA gate). RigRadioControl bridges a live IRigControl into IRadioControl when you have the former and need the latter.

Station control - IRigControl

Get/set frequency and mode, PTT, SWR / RF-power metering, and receive-side DCD / signal-strength reads, all behind capability probes.

IRigControl rig = await RigctldRig.ConnectAsync();   // M0LTE.Rig.Hamlib
// IRigControl rig = await FlrigRig.ConnectAsync();  // M0LTE.Rig.Flrig

await rig.SetFrequencyAsync(14_074_000);
await rig.SetModeAsync(RigMode.PktUsb);

if (rig.Capabilities.HasFlag(RigCapabilities.SwrMeter))
{
    var swr = await rig.ReadSwrAsync();              // dimensionless ratio, 1.0 = perfect
}

if (rig.Capabilities.HasFlag(RigCapabilities.DcdRead))
{
    var busy = await rig.ReadDcdAsync();             // true = carrier present / channel busy
}

Channel sensing - IRadioControl

Push carrier-sense (DCD) edges, RSSI, and transmitter keying - what a MAC layer or CSMA gate wants, because a hardware carrier-sense edge leads the modem's decoded frame by a whole preamble.

IRadioControl radio = new RigRadioControl(rig, ownsRig: true);   // bridge from any IRigControl
// or a native implementation, e.g. M0LTE.Tait.Ccdi's TaitCcdiRadio

radio.CarrierSenseChanged += (_, e) => Console.WriteLine($"channel {(e.Busy ? "busy" : "clear")} at {e.At:O}");

if (radio.Capabilities.HasFlag(RadioCapabilities.RssiRead))
{
    Console.WriteLine($"{await radio.ReadRssiDbmAsync():F1} dBm");
}

A driver can also offer IRadioSideChannel - a small-datagram control plane the radio itself provides (Tait SDM over the radio's internal FFSK modem, for instance), riding the radio's own signalling modem rather than the audio-path modem/TNC. Because it bypasses the audio modem it is mode- and deviation-agnostic, which makes it the natural place to renegotiate the very link it sits beside. Drivers advertise the machinery via RadioCapabilities.SideChannel; consumers must still probe that it is enabled in the radio's programming before gating features on it.

Design

• IRigControl is the cross-backend common subset for CAT control. Everything a backend might lack is gated by RigCapabilities flags discovered at connect time; calling an unadvertised member throws NotSupportedException.
• IRadioControl is the cross-driver common subset for channel sensing, gated the same way by RadioCapabilities. The {RSSI-get, busy-get, PTT-set} subset has held across four implementations without an interface change; reserved flags (channel change, frequency, TX power) exist so richer radios can be described before the interface grows those members - that control belongs to IRigControl instead.
• RigMode wraps a canonical token (hamlib vocabulary: USB, LSB, CW, PKTUSB, ...) with pass-through for backend-native names (RigMode.From("DATA-U")) - mode vocabularies genuinely diverge across backends, so this is not a closed enum.
• Receive-side reads on IRigControl - ReadDcdAsync (true = carrier present / channel busy) and ReadSignalStrengthDbmAsync (dBm) - exist so RigRadioControl can serve IRadioControl's carrier-sense seam from any CAT rig.
• RigRadioControl is poll-synthesised, not push. CAT backends have no notification channel, so DCD is sampled by an owned loop and carrier-sense edges are synthesised from consecutive samples; edges shorter than the poll interval are invisible. A failed read fails open (ChannelBusy = null, so a CSMA gate never blocks on stale information) and backs off to a slower retry cadence until the rig self-heals. ownsRig: true hands the rig's lifetime to the adapter; the default false leaves it with the caller, and dispose best-effort unkeys anything the adapter left keyed.
• Errors are typed: RigConnectionException (link down - retry is sane), RigTimeoutException, RigCommandException (the backend said no; carries its native code), RigProtocolException (unparseable reply).
• Poll-only backends. Current IRigControl backends (rigctld, flrig) have no push channel; callers own their polling cadence. Native IRadioControl drivers (Tait CCDI) push real hardware edges instead.

This package is deliberately dependency-free - it does not pull in the rest of the AX.25 stack of any particular project. Implementations:

• M0LTE.Rig.Hamlib - IRigControl over hamlib's rigctld network protocol (any of hamlib's 200+ rigs, plus the many rigctld-protocol emulators).
• M0LTE.Rig.Flrig - IRigControl over flrig's XML-RPC server.
• M0LTE.Tait.Ccdi (repo) - a Tait TM8100/TM8200 CCDI driver implementing both seams natively: TaitCcdiRadio (IRadioControl with push carrier-sense and IRadioSideChannel) and TaitRigControl, a partial view (PTT + relative RF-power meter) demonstrating a backend that honestly advertises only a slice of the IRigControl surface.

AX.25-specific adapters over IRadioControl (per-frame RSSI tagging, feeding the AX.25 CSMA gate) live in packet-net/packet.net as Packet.Ax25.Radio.

Design and research notes live in packet.net, where this library was written: docs/research/rig-control-spike.md.

AGPL-3.0-licensed. Standalone; used by (among others) the Packet.NET stack.