# PFES Engineering Discoveries

This register consolidates accepted architectural discoveries. Detailed evidence and citations will be added during knowledge migration.

## PFES-DISC-0001

## Discovery

Evidence should remain independent from interpretation.

## Status

Accepted architectural discovery; detailed evidence migration pending.

---

## PFES-DISC-0002

## Discovery

Provenance is part of the engineering artifact.

## Status

Accepted architectural discovery; detailed evidence migration pending.

---

## PFES-DISC-0003

## Discovery

Dependency closure is mandatory for firmware capability transplantation.

## Status

Accepted architectural discovery; detailed evidence migration pending.

---

## PFES-DISC-0004

## Discovery

Behavioral fidelity is more valuable than instruction coverage.

## Status

Accepted architectural discovery; detailed evidence migration pending.

---

## PFES-DISC-0005

## Discovery

Original vendor utilities may contain knowledge absent from extracted payloads.

## Status

Accepted architectural discovery; detailed evidence migration pending.

---

## PFES-DISC-0006

## Discovery

Engineering effort should follow topology rather than precede it.

## Status

Accepted architectural discovery; detailed evidence migration pending.

---

## PFES-DISC-0007

## Discovery

Firmware Engineering and Media Engineering are peer disciplines.

## Status

Accepted architectural discovery; detailed evidence migration pending.

---

## PFES-DISC-0008

## Discovery

Engineering-quality acquisition exceeds consumer-quality acquisition.

## Status

Accepted architectural discovery; detailed evidence migration pending.

---

## PFES-DISC-0009

## Discovery

Native firmware compatibility may avoid unnecessary capability transplantation.

## Status

Accepted architectural discovery; detailed evidence migration pending.

---

## PFES-DISC-0010

## Discovery

Tools resulting from analysis↔upgrade loops document payloads; PFES preserves the engineering system and judgment behind them.

## Status

Accepted architectural discovery; detailed evidence migration pending.

---

---

## PFES-DISC-0011

## Discovery

A firmware-analysis profile becomes substantially stronger engineering knowledge when the same profile produces a complete real-hardware media acquisition whose hashes agree with an independent reference.

## Status

Validated through multiple GDR-8163B firmware revisions and GCC-4244 B103.

---

## PFES-DISC-0012

## Discovery

Logical readiness is not equivalent to physical spindle motion. TEST UNIT READY must not be documented or modeled as a universal spindle-state sensor.

## Status

Validated by audible STOP UNIT behavior followed by GOOD TEST UNIT READY.

---

## PFES-DISC-0013

## Discovery

A useful reconstructed media image may contain synthetic regions, but engineering integrity requires those regions and their source policy to be explicit.

## Status

Adopted in the XGD1 media-profile schema.

## PFES-DISC-0014

## Discovery

Optical-drive command dispatch may be literal, table-driven, computed,
predecoded, or state-machine based. Direct opcode-compare scanners therefore
measure one representation, not command existence.

## Status

Partially corroborated across current analyzer families; GDR-8164B `0xAD`
resolution remains an open proof target.

---

## PFES-DISC-0015

## Discovery

Provenance-distinct firmware instances can remain engineering-distinct even
when their model, revision, or bytes overlap.

## Status

Validated as an analyzer retention requirement for GCC-4244N B103 and
GDR-8164B 0L06 lineages.

---

## PFES-DISC-0016 — READ(10) State-Handoff Closure

The GDR-8050L READ(10) natural handler assembles host LBA into `0x05EC`, writes
state `0x05F0=0x11` and phase `0x06F1=0x04`, and the phase-4 consumer later
copies the LBA into descriptor cell `0x06E4` and arms `0x06E0=0xF0`.

**Status:** Validated for state-handoff scope.

## PFES-DISC-0017 — Media-Window Delta Remains Model-Derived

The current 198,144-sector unlocked mapping is correct in live behavior and the
media profile, but no executed firmware path yet derives or selects it.

**Status:** Open Question.

## PFES-DISC-0018 — HL Timer Loop Interpretation

The GDR HL smoke reaches the handler before stalling in the loop at
`0x90006227..0x90006231`. This is not parser failure; it identifies a timer/MMIO
model boundary.

**Status:** Partially Corroborated.

## PFES-DISC-0019 — Unified Knowledge Graph Baseline

PFES now indexes 590 historical, analyzer, and emulator nodes and 2513 typed traceability edges. The graph preserves proof class and authority instead of flattening all statements into one truth table.

**Status:** Validated.
