The board ACK/NAKs every inbound packet; we were fire-and-forget, so
any corrupt arrival became a permanent state error (stuck-bright /
missed lamps at 62500, where ~6.5% of 4-byte lamp commands lose bytes
to RX-ISR overrun). Now a NAK control byte triggers a resend of the
most recent command packet, bounded by NakRetransmitLimit (default 2;
0 restores fire-and-forget).
Design notes: the wire has no sequence numbers, but every PC->RIO
command is idempotent (lamp state, analog request, reset), so resending
the latest command is safe even in the rare race where the NAK belonged
to an earlier packet. Single control-byte replies (our ACKs) never
participate. NakRetransmits counter surfaced in the mash summary.
6 new tests (retransmit, limit, budget reset, ACK no-op, control-byte
exclusion, disable switch); 281 green.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
- TargetFrameworks net48;net40. net48 keeps x64 + ViGEm + System.IO.Ports
package; net40 adds Microsoft.Bcl.Async + System.ValueTuple and uses the
in-box SerialPort.
- Compat/TaskCompat bridges Task.Run/Delay/WhenAny/WhenAll (TaskEx on
net40) and SemaphoreSlim.WaitAsync (net40 blocks briefly - trivial at
9600 baud).
- IReadOnlyList/IReadOnlyDictionary -> IList/IDictionary throughout
(net40 predates the IReadOnly* interfaces and the Bcl backport cannot
make arrays implement them).
- HashCode.Combine replaced with a manual combine (Bcl.HashCode has no
net40 build); Marshal.SizeOf<T> -> typeof form; ViGEmJoystickSink
gated #if !NET40. HidFeederJoystickSink stays on both flavors - it
will drive RioGamepadXP.sys on XP via the same contract.
Both TFMs build; 275 tests green on net48.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Prepares RioJoy.Core for the net40 (Windows XP) target, which has no
System.Memory, ValueTask, or System.Text.Json:
- IRioTransport and the whole protocol/framing layer now use byte[] +
Task (RioPacket.Payload, PacketParser/Builder, RioChecksum, replies,
AnalogReport, RioHidReport). At 9600 baud Span bought nothing; the
SerialPortTransport bridge copies disappear entirely.
- ConfigStore/OverlayTemplateStore switch to Newtonsoft 13 with the
same conventions (indented, PascalCase, string enums, null-skipping);
verified against the real STJ-written config.json and regions.json
(load + round-trip). System.Memory and System.Text.Json packages
dropped.
275 tests green.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Port the RIO wire protocol from legacy/riovjoy2.cpp into testable C#:
- Protocol/: command + length table, 7-bit checksum, packet builder, and a
streaming receive-side framing state machine (PacketParser) that mirrors the
legacy ReadCommBlock framing/resync (high-bit-mid-packet abort). Typed RIO->PC
decodes: AnalogReport (14-bit sign-extend), VersionInfo, CheckStatus; lamp-state
composition.
- Serial/: RioSerialLink drives an async receive loop with ACK/NAK reply policy
(legacy force-accept vs. opt-in VerifyInboundChecksum), the analog poll timer,
and the >5s reset-recovery watchdog. IRioTransport abstracts the COM port; the
SerialPort-backed transport does 9600 8N1 + DTR reset pulse, and acquire/release
is just create/dispose (foundation for native-game serial yield).
- tests/RioJoy.Core.Tests: 54 xUnit tests covering checksum, framing/resync,
builder round-trips, analog sign-extension + sentinel rejection, lamp combos,
and the read loop driven against an in-memory fake transport.
Hardware verification (version/check/analog against a cabinet) remains; it can't
be done off-device.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
CydandClaude Fable 5