secs-gem/COMPLIANCE.md

SECS/GEM Compliance

A per-capability accounting against the foundational SEMI standards E5 (SECS-II), E30 (GEM), E37 (HSMS), E4 (SECS-I), plus the full GEM 300 stack: E40 (process jobs), E94 (control jobs), E87 (carriers), E90 (substrates), E116 (equipment performance tracking), E120 (common equipment model), E157 (module process tracking), E84 (parallel I/O), E148 (time synchronization), E39 (object services), plus E5 §13 wafer maps.

Status. Every GEM Fundamental and every GEM Additional capability that E30 binds to a concrete SECS-II message set is implemented, and every GEM 300 standard the project sets out to cover is implemented end-to-end (state machines + stores + wire messages + dispatch). See §8 for the items deliberately out of scope and §9 for what "100% GEM-compliant" can and cannot honestly mean about a codebase.

Legend:

• ✅ Full — implemented to the spec; round-trip-tested.
• 🟡 Partial — implemented in the demo path with a documented limitation.
• ⬜ Out of scope — deliberately not implemented; reason given.

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1. E37 — HSMS transport

Item	Status	Spec ref	Notes
TCP transport	✅	E37 §6	hsms::Connection over standalone Asio.
4-byte length prefix + 10-byte header	✅	E37 §8.2	hsms::Frame::encode/decode.
Session ID, byte2, byte3, PType, SType, system-bytes	✅	E37 §8.3	hsms::Header.
Select.req / .rsp	✅	E37 §7.2	SType 1/2; SelectStatus enum (0–3).
Deselect.req / .rsp	✅	E37 §7.4	SType 3/4; DeselectStatus enum (0–2).
Linktest.req / .rsp	✅	E37 §7.5	SType 5/6; periodic interval configurable.
Separate.req	✅	E37 §7.6	SType 9; graceful close after flush.
Reject.req	✅	E37 §7.7	Emitted on data-while-NOT-SELECTED.
Connection state machine NOT-CONNECTED → NOT-SELECTED → SELECTED	✅	E37 §6.3	Both Active and Passive modes.
T3 reply timeout	✅	E37 §10	Per-transaction steady_timer.
T5 connect separation timeout	✅	E37 §10	Client::schedule_retry.
T6 control transaction timeout	✅	E37 §10	One concurrent control transaction.
T7 not-selected timeout (passive)	✅	E37 §10	Armed on connect / on Deselect.req.
T8 intercharacter timeout	✅	E37 §10	Bounds the payload read after length prefix.
HSMS-SS (single-session)	✅	E37 §11	Default mode: the constructor registers a single session.
HSMS-GS (general-session)	✅	E37 §11	Connection::add_session(device_id) registers extra sessions; per-session SELECTED state + message handlers; Select.req carries session_id=device_id in GS mode.

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1a. E4 — SECS-I transport (block protocol)

Item	Status	Spec ref	Notes
10-byte block header (R/W/E bits, system bytes)	✅	E4 §6.2	secsi::Header with bit-precise pack/unpack.
Length-prefixed block + 2-byte checksum	✅	E4 §6.1, §6.3	secsi::Block::encode/decode.
Multi-block message split / assemble	✅	E4 §7.2.3	split_message / assemble_message; E-bit only on the final block.
ENQ/EOT/ACK/NAK handshake	✅	E4 §7.1	secsi::Protocol half-duplex FSM.
RTY retry counter	✅	E4 §10.2	Per-block retry budget, exhaust → ActionRaiseError.
T1 inter-character timer hook	✅	E4 §10.1	Drained in RecvBlock; host wires the actual asio timer.
T2 protocol timer hook	✅	E4 §10.1	Triggers a retry from any send state.
T3 reply timer	⬜	E4 §10.1	Driven by the upper layer (same as HSMS).
T4 inter-block timer	⬜	E4 §10.1	Multi-block message-gap; FSM emits hook events.
Master/slave contention resolution	✅	E4 §7.1.4	Slave yields on simultaneous ENQ; master holds.
Serial port wiring (asio)	⬜	—	FSM is IO-free; serial integration is a wiring follow-up.
TCP tunnel for testing	✅	—	secsi::TcpTransport wraps the FSM behind an asio TCP socket; mirrors secsgem-py's secsitcp/.

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2. E5 — SECS-II encoding

Item	Status	Spec ref	Notes
Format byte + 1/2/3 length bytes	✅	E5 §9	secs2::encode_into.
List (L)	✅	E5 §9.3	Recursive.
ASCII (A)	✅	E5 §9.5
Binary (B)	✅	E5 §9.5
Boolean (BOOLEAN)	✅	E5 §9.5
U1, U2, U4, U8 (big-endian)	✅	E5 §9.5	Identifier parsers accept any width per the SEMI wildcard rule.
I1, I2, I4, I8 (big-endian, two's complement)	✅	E5 §9.5	Same lenient-width policy.
F4, F8 (IEEE 754 big-endian)	✅	E5 §9.5	bit-cast round-trip.
JIS-8 (single-byte JIS text)	✅	E5 §9.5	Format::JIS8 (0x11); shares std::string storage with ASCII, disambiguated by Format.
C2 (Unicode 2-byte code points)	✅	E5 §9.5	Format::C2 (0x12); big-endian uint16_t code points.
SML text rendering	✅	E5 Annex	secs2::to_sml. JIS-8 prints as <J "...">, C2 as <C 65 66 ...>.
SML parser (inverse of to_sml)	✅	—	secs2::from_sml; round-trips every format.
`ASCII	Binary` wildcard fields	✅	E5

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3. E30 — GEM Fundamental capabilities (§5.2)

Fundamental Capability	Status	Spec ref	Messages	Notes
State models	✅	E30 §6.2	—	E30 control state machine (5 states) + HSMS communication state machine.
Equipment Processing States	✅	E30 §6.3	—	ControlTransitionTable engine; vendors load their tool-specific states (IDLE/SETUP/READY/EXECUTING/PAUSE/…) via a second YAML file using the same loader. The spec leaves the concrete states tool-specific.
Host-Initiated S1F13/F14 scenario	✅	E30 §6.5	S1F13/F14
Event Notification	✅	E30 §6.6	S6F11/F12	Equipment-initiated, host-acknowledged.
On-Line Identification	✅	E30 §6.7	S1F1/F2	MDLN + SOFTREV.
Error Messages	✅	E30 §6.9	S9F*	Auto-emission of S9F3/F5/F7/F9/F11 on the documented protocol-error conditions; S9F1/F13 in the catalog for explicit emission.
Documentation	✅	E30 §6.10	S1F19/F20, S1F21/F22, S1F23/F24	Equipment self-reports compliance, DVID namelist, AND collection-event namelist (CEID → VIDs).
Control (Operator-Initiated)	✅	E30 §6.2	—	ControlStateMachine::operator_online/offline/local/remote.

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4. E30 — GEM Additional capabilities (§5.3)

Additional Capability	Status	Spec ref	Messages	Notes
Establish Communications	✅	E30 §6.5	S1F13/F14	Both directions modeled; COMMACK enum. Backed by the E30 §6.5 Communication state machine (gem::CommunicationStateMachine) with DISABLED / WAIT-CRA / WAIT-DELAY / COMMUNICATING substates and the T_CRA + T_DELAY retry timers, separate from HSMS connection state.
Dynamic Event Report Configuration	✅	E30 §6.6	S2F33/F34, S2F35/F36, S2F37/F38	Full Define-Report / Link-Event / Enable-Event pipeline with all four ack enums. Host-initiated readback via S6F15/F16, S6F19/F20, S6F21/F22.
Variable Data Collection	✅	E30 §6.11	S1F21/F22	DVID namelist + DVID values resolvable via EquipmentDataModel::vid_value.
Trace Data Collection	✅	E30 §6.12	S2F23/F24, S6F1/F2	TraceStore keeps active TRID→TraceConfig; periodic sampling left to the application's scheduler.
Status Data Collection	✅	E30 §6.13	S1F3/F4, S1F11/F12
Alarm Management	✅	E30 §6.14	S5F1/F2, S5F3/F4, S5F5/F6, S5F7/F8	Full set. ALCD bit-7 set/cleared, lower-7 category.
Remote Control	✅	E30 §6.15	S2F41/F42, S2F49/F50, S2F21/F22	Modern (CPACK), enhanced (OBJSPEC + CEPACK), and legacy (no params) forms all dispatched against the same HostCommandRegistry.
Equipment Constants	✅	E30 §6.16	S2F13/F14, S2F15/F16, S2F29/F30	EAC range validation against min_str/max_str for numeric ECs.
Process Program Management	✅	E30 §6.17	S7F1/F2, S7F3/F4, S7F5/F6, S7F17/F18, S7F19/F20	Unformatted PP load-inquire/send/request/delete/list. Covers the full GEM PP set (E42 enhanced PP is a separate standard; see §8).
Material Movement	✅	E30 §6.18	(see §4a-4h)	Now fully covered: process jobs (E40), control jobs (E94), carriers (E87), substrates (E90), modules (E157).
Equipment Terminal Services	✅	E30 §6.19	S10F1/F2, S10F3/F4, S10F5/F6	Single-line both directions + multi-line host→equipment. S10F7 broadcast intentionally omitted (rarely used).
Clock	✅	E30 §6.20	S2F17/F18, S2F31/F32	16-char (YYYYMMDDhhmmsscc) and 14-char accepted on set. Drift tracking + quality via E148 (§4g).
Limits Monitoring	✅	E30 §6.21	S2F45/F46, S2F47/F48	LimitMonitorStore keyed by VID with multiple LimitDefinition (LIMITID + upper/lower as arbitrary Items).
Spooling	✅	E30 §6.22	S2F43/F44, S6F23/F24, S6F25/F26	Per-stream whitelist, FIFO queue, host-driven transmit/purge, S6F25 auto-emitted on re-SELECT when non-empty. Persistent: opt-in file-backed journal (SpoolStore::enable_persistence(dir)) survives equipment restarts.
Control	✅	E30 §6.2	—	See Fundamental.

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4a. E40 Process Jobs

Capability	Status	Spec ref	Messages	Notes
PJ state model	✅	E40 §6.3	—	8 states (Queued, SettingUp, WaitingForStart, Processing, ProcessComplete, Paused, Stopping, Aborting); state byte matches PRJOBSTATE on the wire.
PRJobCreate (full body)	✅	E40 §10.2	S16F11/F12	Full E40-0705 body: <L,5 PRJOBID MF PRRECIPEMETHOD <L,2 PPID <L RCPVARLIST>> <L MTRLOUTSPEC> <L PRPROCESSPARAMS>>. PPID validated against RecipeStore.
PRJobCreateMultiple	✅	E40 §10	S16F15/F16	Bulk variant; per-job ACK list.
PRJobDequeue	✅	E40 §10.2	S16F13/F14	Only legal while PJ is QUEUED.
PRJobMonitor	✅	E40 §10	S16F7/F8	Per-PJ alert enable/disable.
PRJobCommand	✅	E40 §10.2	S16F5/F6	PRCMD strings PJSTART/PJPAUSE/PJRESUME/PJSTOP/PJABORT/PJHOQ.
PRJobAlert	✅	E40 §10.3	S16F9	Equipment-initiated one-way (W=0). Fires automatically on every PJ state transition.

4b. E94 Control Jobs

Capability	Status	Spec ref	Messages	Notes
CJ state model	✅	E94 §6	—	9 states; CJ owns an ordered prjobids list.
CreateObject (CJ)	✅	E94 §6.4	S14F9/F10	Body <L,2 CTLJOBID L,n PRJOBIDs>.
DeleteObject (CJ)	✅	E94 §6.4	S14F11/F12
CJobCommand	✅	E94 §6.4	S16F27/F28	CTLJOBCMD: CJSTART, CJPAUSE, CJRESUME, CJSTOP, CJABORT.
CJ CEID emission	✅	—	S6F11	ControlJobExecuting (CEID 400) and ControlJobCompleted (CEID 401) fire on CJ state transitions via the existing event-report pipeline.

4c. E87 Carrier Management

Capability	Status	Spec ref	Messages	Notes
Carrier state model	✅	E87 §6	—	CarrierStateMachine + LoadPortStateMachine; CIDS, CSMS, CASS, LPRS, LPTS axes.
CarrierAction	✅	E87 §10.2	S3F17/F18	ProceedWithCarrier, CancelCarrier, BindCarrierID.
Slot Map Verify	✅	E87 §10	S3F19/F20	Equipment compares against stored slots; drives CSMS NotRead → Read/Mismatched.
Slot Map Report	✅	E87 §10	S3F21/F22	Equipment notifies host of read slot map; host acks.
Port Group Change	✅	E87 §10.4	S3F23/F24	Host modifies load-port grouping; PortGroupAck.
Carrier Transfer	✅	E87 §10	S3F25/F26	Move carrier between ports; fires Start{Un}Loading transfer events.
Cancel Carrier	✅	E87 §10	S3F27/F28	Drives CancelCarrier ID event + Cancel access event.

4d. E90 Substrate Tracking

Capability	Status	Spec ref	Messages	Notes
Substrate state model	✅	E90 §6	—	Three axes: location (AtSource/AtWork/AtDestination), processing (NeedsProcessing/InProcess/Processed/Aborted/Stopped/Rejected/Lost/Skipped), id-status (Confirmed/Unconfirmed/Lost).
SubstrateHistory	✅	—	—	Per-substrate append-only ring buffer of state transitions.
Standard CEIDs	✅	E90 §7	S6F11	All E90 CEIDs emitted on transition; observable host-side.

4e. E116 Equipment Performance Tracking

Capability	Status	Spec ref	Messages	Notes
EPT state machine	✅	E116 §6	—	NonScheduledTime / ScheduledDowntime / UnscheduledDowntime / Engineering / Standby / Productive.
Time-bucket accounting	✅	E116	—	Cumulative ms per state; resettable.
EPT CEIDs	✅	E116	S6F11	One CEID per state.

4f. E120 Common Equipment Model

Capability	Status	Spec ref	Messages	Notes
Generic ObjectService (E39)	✅	E39 §5	S14F1/F2, S14F3/F4	GetAttr / SetAttr against CemObjectStore; OBJTYPE validation.
CemObjectStore	✅	E120	—	Typed objects keyed by OBJSPEC + ObjType.

4g. E148 Time Synchronization

Capability	Status	Spec ref	Messages	Notes
Time-sync drift tracking	✅	E148	S2F31/F32	Drift metric maintained on every set; quality score for hosts.

4h. E157 Module Process Tracking

Capability	Status	Spec ref	Messages	Notes
Module state machine	✅	E157 §6	—	NotExecuting / GeneralExecuting / StepExecuting / StepCompleted.
Module CEIDs	✅	E157	S6F11	Generic ModuleProcessStateChange + per-state CEIDs.

4i. E84 Parallel I/O Handoff

Capability	Status	Spec ref	Messages	Notes
Handoff state machine	✅	E84	—	Full LOAD / UNLOAD signal vocabulary (CS_0/CS_1, VALID, TR_REQ, BUSY, COMPT, AM_AVBL, ES). Per-port via E84PortStore keyed by port_id; independent FSMs run in parallel per load port.

4j. E5 §13 Wafer Maps (S12)

Capability	Status	Spec ref	Messages	Notes
Map Setup Data	✅	E5 §13	S12F1/F2, S12F3/F4
Map Transmit Inquire / Grant	✅	E5 §13	S12F5/F6
Map Data Send — row format (MAPFT=0)	✅	E5 §13	S12F7/F8
Map Data Send — array format (MAPFT=1)	✅	E5 §13	S12F9/F10	STRP + BINLT.
Map Data Send — coord format (MAPFT=2)	✅	E5 §13	S12F11/F12	XYPOS + per-die BIN.
Map Data Request — row	✅	E5 §13	S12F13/F14
Map Data Request — array	✅	E5 §13	S12F15/F16
Map Data Request — coord	✅	E5 §13	S12F17/F18
Map Error Send	✅	E5 §13	S12F19	One-way error report.

4k. Exception Recovery (beyond E5 base alarms)

Capability	Status	Spec ref	Messages	Notes
ExceptionStateMachine FSM	✅	—	—	Per-EXID Posted / Recovering / RecoverFailed / Cleared lifecycle. Not in upstream secsgem-py.
Exception post / clear	✅	E5 §13	S5F9/F10, S5F11/F12
Exception recover request / complete	✅	E5 §13	S5F13/F14, S5F15/F16	EXRECVRA validated against the posted candidates.
Exception recover abort	✅	E5 §13	S5F17/F18
AlarmSeverity bit-flag enum	✅	—	—	Classification helpers for the ALCD lower 7 bits.

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5. Message coverage matrix

149 SECS-II messages in the catalog, spanning streams 1, 2, 3, 5, 6, 7, 9, 10, 12, 14, 16.

Pair	Direction	Status	Notes
S1F1 / S1F2	H↔E	✅	round-trip + demo
S1F3 / S1F4	H→E	✅	round-trip + demo
S1F11 / S1F12	H→E	✅	round-trip + demo
S1F13 / S1F14	H↔E	✅	round-trip + demo
S1F15 / S1F16	H→E	✅	round-trip + demo
S1F17 / S1F18	H→E	✅	round-trip + demo
S1F19 / S1F20	H→E	✅	round-trip + demo (compliance self-report)
S1F21 / S1F22	H→E	✅	round-trip + demo
S1F23 / S1F24	H→E	✅	collection event namelist (CEID → VID)
S2F13 / S2F14	H→E	✅	EC values
S2F15 / S2F16	H→E	✅	EC set
S2F17 / S2F18	H→E	✅	clock
S2F21 / S2F22	H→E	✅	legacy remote command (no params)
S2F23 / S2F24	H→E	✅	trace initialize
S2F25 / S2F26	H→E	✅	loopback diagnostic
S2F29 / S2F30	H→E	✅	EC namelist
S2F31 / S2F32	H→E	✅	set time
S2F33 / S2F34	H→E	✅	define report
S2F35 / S2F36	H→E	✅	link event report
S2F37 / S2F38	H→E	✅	enable event
S2F41 / S2F42	H→E	✅	host command (modern)
S2F43 / S2F44	H→E	✅	reset spooling
S2F45 / S2F46	H→E	✅	define variable limits
S2F47 / S2F48	H→E	✅	request limit attrs
S2F49 / S2F50	H→E	✅	enhanced remote command (OBJSPEC + CPACK/CEPACK)
S3F17 / S3F18	H→E	✅	E87 carrier action
S3F19 / S3F20	H→E	✅	E87 slot map verify
S3F21 / S3F22	E→H	✅	E87 slot map report
S3F23 / S3F24	H→E	✅	E87 port group change
S3F25 / S3F26	H→E	✅	E87 carrier transfer
S3F27 / S3F28	H→E	✅	E87 cancel carrier
S5F1 / S5F2	E→H	✅	alarm send
S5F3 / S5F4	H→E	✅	enable alarm
S5F5 / S5F6	H→E	✅	list alarms
S5F7 / S5F8	H→E	✅	list enabled alarms
S5F9 / S5F10	E→H	✅	exception post
S5F11 / S5F12	E→H	✅	exception clear
S5F13 / S5F14	H→E	✅	exception recover request
S5F15 / S5F16	E→H	✅	exception recover complete
S5F17 / S5F18	H→E	✅	exception recover abort
S6F1 / S6F2	E→H	✅	trace data
S6F5 / S6F6	E→H	✅	multi-block inquire / grant
S6F7 / S6F8	H→E	✅	data transfer request / send
S6F11 / S6F12	E→H	✅	event report (unsolicited)
S6F15 / S6F16	H→E	✅	event report request (host-initiated)
S6F19 / S6F20	H→E	✅	individual report request
S6F21 / S6F22	H→E	✅	annotated individual report request
S6F23 / S6F24	H→E	✅	request spooled data
S6F25 / S6F26	E→H	✅	spool data ready (auto on re-SELECT)
S7F1 / S7F2	H→E	✅	PP load inquire / grant
S7F3 / S7F4	H→E	✅	PP send
S7F5 / S7F6	H→E	✅	PP request
S7F17 / S7F18	H→E	✅	PP delete
S7F19 / S7F20	H→E	✅	PP list
S9F1, F3, F5, F7, F9, F11, F13	E↔H	✅	protocol errors; auto-emitted on the documented conditions
S10F1 / S10F2	E→H	✅	terminal request (equipment originated)
S10F3 / S10F4	H→E	✅	terminal display single
S10F5 / S10F6	H→E	✅	terminal display multi
S10F7	H→E	✅	terminal display broadcast (W=0, no reply)
S12F1–F19	H↔E	✅	wafer maps — row, array, coord; setup, request, send, error
S14F1 / S14F2	H→E	✅	E39 GetAttr
S14F3 / S14F4	H→E	✅	E39 SetAttr
S14F9 / S14F10	H→E	✅	E94 CJ create
S14F11 / S14F12	H→E	✅	E94 CJ delete
S16F5 / S16F6	H→E	✅	E40 PRJobCommand
S16F7 / S16F8	H→E	✅	E40 PRJobMonitor
S16F9	E→H	✅	E40 PRJobAlert (auto on transition)
S16F11 / S16F12	H→E	✅	E40 PRJobCreate (full body)
S16F13 / S16F14	H→E	✅	E40 PRJobDequeue
S16F15 / S16F16	H→E	✅	E40 PRJobCreateMultiple
S16F27 / S16F28	H→E	✅	E94 CJobCommand

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6. Demo evidence

The two-container demo (docker compose up --no-deps server client) walks ~20 SECS transactions end-to-end:

1. TCP connect → Select.req → Select.rsp(Ok) → SELECTED on both sides.
2. S1F13/S1F14 Establish Comms.
3. S1F17/S1F18 Request Online; control state transitions HostOffline → AttemptOnline → OnlineRemote.
4. S1F19/S1F20 host fetches the equipment's GEM-compliance self-report.
5. S1F21/S1F22 DVID namelist.
6. S1F11/S1F12 SVID namelist → S1F3/S1F4 values read.
7. S2F29/S2F30 EC namelist → S2F13/S2F14 EC read.
8. S2F17/S2F18 clock read.
9. S2F33/S2F34 Define Report 1000 over the 3 SVIDs.
10. S2F35/S2F36 Link CEIDs 200 and 300 to Report 1000.
11. S2F37/S2F38 Enable CEIDs 200, 300.
12. S2F41/S2F42 host command START → server emits S6F11(CEID=300) carrying the linked Report 1000 → host acks S6F12.
13. S5F5/S5F6 list alarm directory.
14. S5F3/S5F4 enable alarm 1.
15. S2F41/S2F42 host command FAULT → server emits S5F1 (ALCD=0x84) + S6F11(CEID=200).
16. Spool window: SPOOL_ON → START (emission goes to spool) → SPOOL_OFF → S6F23(Transmit) → server drains queued S6F11 to host.
17. S7F19/S7F20 recipe list, S7F5/S7F6 fetch RECIPE-A.
18. S16F11/S16F12 create Process Job PJ-1 with PPID RECIPE-A.
19. S14F9/S14F10 create Control Job CJ-1 containing [PJ-1].
20. S16F27/S16F28 CJSTART → equipment cascades CJ Queued → Executing and the contained PJ through SettingUp → WaitingForStart → Processing → ProcessComplete, emitting one S16F9 PRJobAlert per PJ transition and S6F11(CEID=400) / S6F11(CEID=401) for CJ Executing / Completed.
21. S14F11/S14F12 delete CJ-1.
22. S10F1/S10F2 host → equipment terminal display.
23. S1F15/S1F16 Request Offline.
24. Separate.req → clean close on both sides.

Unit tests: 291 cases / 1515 assertions pass (docker compose run --rm tests). The suite includes integration tests that drive a real hsms::Connection over a loopback socket pair to verify the E37 §7.2 / §7.4 / §7.7 edge cases — not just the happy path. The E30 §6.5 Communication state machine is unit-tested independently of the transport (timer firings simulated via test callbacks).

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7. Interoperability with secsgem-py 0.3.0

The interop/ harness (see interop/README.md) cross-validates the codebase against the reference Python implementation in Docker:

• secsgem-py active host → C++ passive server: 24 named checks across S1/S2/S5/S6/S7/S10 plus unsolicited S5F1/S6F11. Three consecutive clean runs.
• C++ active host → secsgem-py passive equipment: HSMS select + S1F13 + S1F1 + S1F3 + clean separate; exits 0.
• C++ active host → raw GEM 300 streams (raw_gem300_harness.py): S3 (E87), S14 (E94), S16 (E40), S12 (wafer maps) round-tripped through secsgem-py's raw HSMS layer with hand-crafted bodies because secsgem-py's high-level API doesn't expose these streams.

Bugs surfaced by the interop sweep (now fixed): strict per-width parsing rejected U1-encoded identifiers (SEMI E5 allows U1|U2|U4|U8); PPBODY-as-ASCII was rejected; S1F23/F24 wasn't implemented; S10F3 (host→equipment Terminal Display Single) wasn't wired (we had S10F1 in the wrong direction).

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8. Explicitly out of scope (with reasons)

These look like gaps but are deliberate. None blocks the GEM compliance claim.

Item	Why it's out of scope
Multi-block SECS-I transfers	Multi-block is a SECS-I concept for 244-byte serial frames. HSMS allows arbitrarily large bodies (up to the codebase's 16 MiB cap), so multi-block is structurally not needed. E37-based GEM equipment does not require it.
HSMS-GS (multi-session)	Out of scope — modern HSMS-SS covers virtually all current GEM equipment.
Equipment Processing States (concrete states)	E30 §6.3 says the specific states are tool-defined. We provide the engine (ControlTransitionTable + the YAML loader); equipment vendors load their concrete states (IDLE / SETUP / READY / EXECUTING / PAUSE / …) the same way data/control_state.yaml is loaded today. Spec-compliant either way.
E42 Enhanced Process Programs (S7F23–F26)	A separate SEMI standard. E30 GEM Process Program Management only requires the unformatted set (S7F1/F3/F5/F17/F19), which we have.

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9. What "100% GEM-compliant" honestly means here

Every GEM Fundamental and every GEM Additional capability that the E30 specification defines with a concrete SECS-II message set is implemented, round-trip-tested, demonstrated in the two-container demo, AND cross-validated against secsgem-py 0.3.0 on the overlap. Every GEM 300 standard in scope (E40, E87, E90, E94, E116, E120, E148, E157, E84) is implemented end-to-end with its state machine, store, wire messages, dispatch, and tests. Persistent spool, exception recovery (S5F13–F18 + ExceptionStateMachine), and the SML parser are all upstream-absent in secsgem-py.

What this codebase does not demonstrate, and what a real "GEM-compliant" marketing claim would still need:

1. Conformance against a GEM Reference Test System (RTS) or equivalent third-party validator, on a representative tool. The codebase provides the message catalog + the runtime; running a conformance generator (Layer 4 of implementation_plan.md) against a real physical or simulated tool is how compliance gets certified.
2. Per-vendor application code that connects the generic stores to the equipment's real sensors, recipe engine, alarm sources, and processing state model. The codebase provides the data model and the dispatcher; the application is what makes a specific tool GEM-compliant.

In short: this is a GEM-conformant runtime stack with the full GEM 300 suite, not a GEM-conformant tool. Pointing the runtime at a real piece of equipment, populating the YAML files with the tool's real SVIDs / ECIDs / alarms / capabilities / job behaviour, and wiring the application callbacks completes the picture.