Depz.Sensor 0.2.1

Depz.Sensor (C# SDK)

A contract-first decode/encode SDK for the DEPZ sensor family. Every codec is a byte-exact port of the reference Python SDK, pinned to the shared golden vectors under contracts/vectors (dotnet test).

Documentation

Full docs live under docs/:

• Common guide — what it is, install, discovery, the mental model, transport/CRC, datasets, firmware parse, testing, extension points.
• API reference — every public type, generated from the /// summaries (per-sensor: SR04 · VL53L8CX · VL53L8CH · BNO086).
• Per sensor — SR04 (intro · guide), VL53L8CX (intro · guide), VL53L8CH (intro · guide), BNO086 (intro · guide).

Regenerate the API reference after changing source /// summaries:

python3 scripts/gen_api_md.py    # from packages/depz-sensor-sdk-csharp

Sensors

The DEPZ line exposes four distinct user-facing sensor types. The ToF is two separate silicon variants that share one wire/frame layout:

VL53L8CX vs VL53L8CH

VL53L8CX is the base ToF and the development default (it enumerates under the raw ST VID/PID until reprogrammed). VL53L8CH is a superset: same ranging engine plus CNH (compact new histograms), and it ships with its own production USB PID (0xED40, hinted vl53l8ch).

Because both variants stream the same ULD results-frame layout, a single decode path serves both:

• Vl53l8FrameDecoder — results-frame decode (distance/status/signal/…), shared by CX and CH. The only variant-visible difference is the frame-id footer offset (CX FW / ULD 2.1.0 = 12 bytes from end; CH FW / VL53LMZ 2.0.16 = 4). Select with Vl53l8FrameDecoder.ForVariant(Vl53l8Variant.Cx | .Ch).
• Vl53l8Advanced / MotionConfig — advanced DCI codecs (motion-indicator config, detection thresholds, xtalk margin). Shared by CX and CH.

Coverage today

Verifiable, golden-vector-backed codecs are implemented for all five sensors:

• SR04 — command encode + data/period/decay decode.
• VL53L4CD — register-bridge codecs, result decode, timing/tuning math and init block.
• VL53L8CX / VL53L8CH — framing → chunk reassembly → results-frame decode (shared), plus the advanced DCI codecs (shared). Exercised end-to-end by a recorded .depzrec replay.
• BNO086 — SHTP framing/reassembly, SH-2 control encode, input-report and gyro-integrated-RV decode.

Plus the shared foundation: CRC KATs, DEPZ framing encode/decode, USB identity table + discovery ordering, common commands (time-sync, sync-pin), .fwdepz image parse, and .depzdata dataset read.

Not-yet-implemented extension points

These are deliberately stubbed (clearly-named, throwing/TODO stubs) rather than faked, because they cannot be verified from golden vectors alone:

• CNH histogram decode (VL53L8CH-specific) — Vl53l8Cnh. The CH-only compact histogram block is not decoded yet; it is the CH extension point over the shared CX/CH frame decode. No fabricated implementation.
• Live VL53L8 ULD init/config — Vl53l8Uld. The firmware-download + register-bridge (DCI) init sequence only means anything against real silicon over the CDC link, so it is out of scope for the decode SDK.

Everything else in the table above is fully implemented and covered.

License

MIT. Open source — source and issue tracker: https://github.com/depz-ai/depz-sensor-sdk.