CanKit.Pro.Uds 1.2.3

CanKit.Pro.Uds

Experimental Unified Diagnostic Services (UDS, ISO 14229-1:2020) client for CanKit.Pro. Sits directly on top of CanKit.Pro.IsoTp's IIsoTpChannel, so anything that speaks ISO-TP (virtual loopback, PCAN, SocketCAN, Vector, Kvaser, ZLG, ControlCAN, ...) can be driven with the same client.

Status: published on nuget.org since 1.2.0. The public surface is stable for the services listed below; the shape of SendRawAsync, timing options and NRC-mapping types may still shift in a future major version.

Service coverage (SRS FR-UDS-001..012)

Quick start

using CanKit.Core;
using CanKit.Abstractions.API.Can.Definitions;
using CanKit.Pro.IsoTp;
using CanKit.Pro.Uds;
using IsoTpFactory = CanKit.Pro.IsoTp.IsoTp;

using var bus = CanBus.Open(
    "virtual://demo/0",
    cfg => cfg.SetProtocolMode(CanProtocolMode.Can20).Baud(500_000));

var endpoint = IsoTpEndpoint.Normal(txCanId: 0x7E0, rxCanId: 0x7E8);
using var isoTp = IsoTpFactory.Open(bus, endpoint);
using var uds = UdsClient.Create(isoTp, new UdsClientOptions
{
    P2ClientMax = TimeSpan.FromMilliseconds(50),
    P2StarClientMax = TimeSpan.FromSeconds(2),
});

await uds.DiagnosticSessionControlAsync(UdsSessionType.Extended);
using var _ = uds.StartTesterPresentKeepAlive();

byte[] vin = await uds.ReadDataByIdentifierAsync(0xF190);
await uds.SecurityAccessAsync(
    requestSeedLevel: 0x01,
    computeKey: seed => YourAlgorithm.ComputeKey(seed));

// One-shot download (FR-UDS-012): negotiate maxNumberOfBlockLength, chunk the payload,
// walk the block-sequence counter (0x01..0xFF, wraps to 0x00), close with RequestTransferExit.
await uds.DownloadAsync(
    dataFormatIdentifier: 0x00,                            // no compression / no encryption
    addressAndLengthFormatIdentifier: 0x44,                // 4-byte address, 4-byte size
    memoryAddress: new byte[] { 0x00, 0x10, 0x00, 0x00 },
    memorySize:    new byte[] { 0x00, 0x00, 0x02, 0x00 }, // 512 bytes
    data: firmwareChunk);

Design notes

• One client = one tester ↔ ECU relationship. Requests are serialized through an internal SemaphoreSlim so at most one UDS transaction is on the wire (ISO 14229-1 §7.3).
• The client never buffers responses; each ReceiveAsync is a bounded wait derived from the active timing budget (P2 first, then P2* after every 0x78).
• Stray or mismatched responses received while a request is pending are silently discarded; the wait continues inside the same budget so a chatty ECU cannot extend a P2 window.
• Transport-layer failures (ISO-TP timeout, overflow, WFTmax, etc.) are re-thrown as their original IsoTpException subclasses so callers can distinguish "ECU said no" from "wire broken".

Documentation

• Requirements: docs/requirements/SRS-CanKit.Pro.md §4.3.1
• Architecture: docs/architecture/arc42-CanKit.Pro.md §6.5 (e) — UDS request/response with NRC 0x78

Install

dotnet add package CanKit.Pro.Uds

# plus a CanKit adapter for the hardware you actually talk to, e.g.
dotnet add package CanKit.Adapter.Virtual   # loopback, no hardware

Dependencies: CanKit.Abstractions, CanKit.Pro.Actor, CanKit.Pro.IsoTp, CanKit.Pro.RawCan, CanKit.Pro.Reliability.

Part of CanKit.Pro — higher CAN protocol layers built on top of CanKit, which is consumed as a NuGet package rather than forked.

License

MIT — see LICENSE. CanKit itself is a separate project licensed under Apache-2.0; see THIRD-PARTY-NOTICES.md.