- The background probe reported the host Stopped whenever a read pass held
_gate past the probe deadline: contention is the connection being used,
not lost. A contended tick now gives no verdict (counted for tests); a
real probe failure still reports Stopped. A tick that races a teardown no
longer reopens a connection on an uninitialised driver.
- S7DriverProbe deserialised S7DriverOptions directly, whose Timeout is a
TimeSpan no config names, so "timeoutMs" was ignored and every handshake
waited the whole Test Connect budget. The handshake and test read are now
bounded by timeoutMs, capped by the caller's timeout.
Refs #742
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
A span's block is the union of its members' ranges, so one member that runs
past the DB's real end (or over-declares a STRING) made the CPU refuse the
whole block, and every neighbour within it was Bad on every poll. The
planner's stated invariant (a grouped read cannot fault where per-tag reads
would succeed) was false; the multi-var path already fell back, spans did not.
- A refused multi-member span hands its members back; they are read one at a
time for that pass, bypassing the multi-var pass.
- _noGroup remembers the members refused on their own (or every member when
none was) and keeps them out of later plans, so the rest group again. It is
cleared by every initialize publish. Non-refusal span failures are
unchanged (every member stamped).
- The once-per-tag refusal Warning memo (R07:H4) is now also cleared by the
publish, and shutdown resets the write-side Degraded owner, as documented.
- Live gate: MW10 + MD254 (2 bytes past the 256-byte M area) merged into one
refused block; MW10 keeps reading 4097 on every pass.
Refs #742
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
No read or write loop checked _plcDead between items: on a frozen-but-
established peer the first op blew its deadline and marked the handle dead,
and every remaining span / tag / write still went to the wire and could wait
its own deadline under _gate (a 20-span pass ~100 s), with Degraded and the
comms-loss watchdog's clock deferred until the pass ended.
- The span loop, the multi-var chunk loop, the per-tag loop and the write
loop stamp BadCommunicationError without I/O once _plcDead is set.
- A multi-var chunk that dies on a transport loss (socket / IO / timeout /
ConnectionError) marks the handle dead instead of falling back to one
doomed per-tag read per member. The framing class is deliberately excluded
there: snap7/S7.Net report a multi-var with one refused item as
ReadData(WrongNumberReceivedBytes) over a healthy stream.
- Live gate via an in-test freezable TCP proxy (counts request frames, not
seconds). Mutation shows S7.Net 0.20 already self-closes on a cancelled op,
so the gate pins the end-to-end property; the driver guard itself is proven
by the unit tests (an op that ignores its token keeps the socket open).
Refs #742
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
A deterministic PLC refusal (object does not exist, address out of range,
type inconsistent...) degraded driver health, and an all-refused driver (a
wrong DB number) sat Degraded with LastSuccessfulRead frozen, so the 90 s
comms-loss watchdog reconnected it forever against a reachable PLC.
- IsRefusal / IsAccessDenied classify over the whole exception chain. Live
probe on the snap7 fixture: S7.Net's READ paths raise the item error as a
BARE Exception ("Received error from PLC: ..."), its write paths as
PlcException(WriteData). The old PlcException-only match missed the read
shape entirely, so a real read access-denied was BadCommunicationError +
Degraded instead of the Faulted PUT/GET alert; the Test Connect probe had
the same blind spot.
- A refusal (read or write) is BadDeviceFailure with a once-per-tag Warning,
no health write and no reopen; it counts as answered, so it advances
LastSuccessfulRead and restores Healthy after a comms fault. An undecodable
buffer (S7ValueRangeException) also counts as answered.
- A write batch the CPU answered without a failure advances
LastSuccessfulRead and retires a Degraded the write side itself published.
- Tests that used ReadData as their generic "device fault" now use SendData
so their Degraded leg is still exercised.
Refs #742
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
Review m-2. A Calculation driver's own maxAllocBytesPerRun /
quarantineAfterConsecutiveTimeouts used to be clamped silently by
ScriptRunGuard. ResolveScripting now sanitizes the layered options
itself and returns the adjustments, and the factory logs one Warning
per clamped value, naming the driver. docs/ScriptEditor.md "Runtime
safety" gains the key table: defaults, the 1 MB allocation floor, the
1000 caps, NaN and disable semantics, and the per-driver override.
docs/Configuration.md has no Scripting section, so these keys have no
other home.
Refs #731#734
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
Overlapping InitializeAsync calls (the actor's fire-and-forget init plus a
retry tick) could leak an opened PLC connection and orphan a probe loop: no
gate guarded the lifecycle, only _gate for I/O.
- _lifecycleGate (the Modbus pattern) serialises Initialize / Reinitialize /
Shutdown / Dispose; teardown waits a bounded time, then tears down anyway.
- Every initialize and teardown starts a lifecycle generation. Health writes
(init, read/write passes, poll errors, shutdown) and the init publish carry
it and are dropped once it has moved on, so an abandoned init never
publishes over a later shutdown and a shutdown's final write never clobbers
a newer init. A superseded init disposes what it opened and throws.
- The init publish (options, tag tables, Plc, probe loop) happens under _gate;
the tag tables are built fresh and swapped by one reference write instead of
being cleared in place under live poll passes.
- Read/write passes re-check initialization under _gate, so a pass that waited
out a teardown cannot reopen a connection on a shut-down driver.
- The semaphores are no longer disposed: Dispose can race a running shutdown.
Refs #742
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
N1: a refusal of the DWORD-addressed request permanently settled the layout
as per-element, so a tag deployed before the online edit that creates its
BOOL array later read DWORD n and published byte 0 as Good. The native runtime
now keeps an explicit layout (Unsettled / Packed / PerElement) that ONLY a
reply type changes: 0xD3 settles packed (Bits[n/32], bit n%32), 0xC1 settles
per-element (Bits[n]). Refusals and comms faults leave it unsettled, so the
next read asks again. A reply whose type disagrees with the addressing it was
asked under is discarded and re-read once under the shown layout (it would be
some other element), also when an online edit re-types a settled array. A
scalar BOOL answered 0xD3 with no element bit, or not settled packed, is
refused BadTypeMismatch instead of decoding byte 0.
m1: the write-owned Degraded marker is set together with the CAS that installs
it, under one lock, so concurrent failing writes cannot leave it naming a
different instance (a good write then clears it); a refusal-only read batch
still keeps it write-owned.
m2/m3/m5: documented (breaker accounting of a superseded init; libplctag
throw-only NotImplemented assumption; the TypeMismatch write status word is
libplctag-only).
m4: test for a write on an unsettled layout (settles by a read first).
Refs #737
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
The init-time tag guards THREW: one mis-authored tag (DB1.DBZ0, DB1.DBW0 typed
Float64, T5 typed Int32, a writable Bool array) faulted the whole driver and the
actor retried the same init every 10 s forever, darkening every tag on the PLC.
Neither the editor nor the deploy gate checked any of it.
- S7AddressParser moves to S7.Contracts (same namespace) and a new
S7TagShapeRules there is the single authority on servable shapes.
- S7TagDefinitionFactory.FromTagConfig applies it, so the AdminUI editor, the
deploy gate (Inspect, with the specific reason) and the driver init refuse
the same tags. Init now skips a refused tag (ISkippedTagReporter) instead of
throwing; the throwing RejectUnsupportedTagConfigs is gone.
- New rules on top of the old guards: a narrow type at the wrong access width
(every read failed) and a Bool array not starting at bit 0 (U4: DB1.DBX0.3
silently read bit 0 of bytes 0..n).
- AdminUI test fixtures that used addresses the driver could never serve
(DB1.DBS0, a browse "SomeAddress", Int32/Float32 on DBW) now use real ones.
Refs #742
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
- I1: the poll engine belongs to a teardown generation. ShutdownAsync/Dispose
retire the current engine and install a fresh one in the same swap as the
device/tag tables, then dispose the retired one (possibly in the background
after a cancelled or over-budget shutdown). A subscription made after the
next InitializeAsync can no longer land in an engine whose late dispose tail
would dispose its CTS without cancelling it (a loop no UnsubscribeAsync could
find). Poll handles are generation-qualified (TwinCATPollHandle) because each
engine numbers handles from 1; SubscribeAsync re-homes a subscription that
raced a retirement.
- M1: a write's status feeds per-device health - Good clears that device's
comms fault and advances LastSuccessfulRead, a comms status degrades, a
refusal keeps the state.
- M2: a symbol-version re-arm bumps a per-registration epoch; an in-flight
retry that fails afterwards no longer re-imposes the backoff.
- M3: a re-arm restarts the refusal backoff at 30 s.
- M4: documented that PLC-not-in-RUN detection needs the probe.
- M5: WSTRING and multi-dimensional array encode-plan tests; the cancelled-
shutdown test asserts Unknown health and awaits its background teardown.
- M6: an infinity spelled as a string ('Infinity', '-inf') passes like a
float/double infinity; a finite overflow stays BadOutOfRange.
Refs #739
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
N1: linkDown is set only when NO reply arrived, i.e. a timeout, a transport exception or
a connect failure. A status the CNC returned proves it answered. EW_REJECT and every
unlisted rc map to BadCommunicationError, so a deterministic rc on one tag used to fail
every later tag of a reachable control on every poll. The comms-classed status still
degrades health. The coalescer already treated a returned refusal this way; it is
unchanged.
Tests: a returned EW_REJECT on tag 1 leaves tags 2 and 3 read and Good (red before). A
timeout still fails the rest without reading them (positive control).
Minors:
- m1: the _lifecycleLock doc now covers the health transitions it also guards.
- m2: the NoteFixedTreeFailed summary says a refusal credits the answer.
- m3: ReadAsync stamps a failed batch's exception with the generation the batch started
under, and HandlePollError degrades that generation only.
- m4: the fixed-tree "blip" absence check runs unconditionally under a wide budget, and
asserts that both ticks landed inside it.
- m5: direct unit cases for the coalescer link-down paths. A transport fault on the first
range fails the second range and the per-tag tag without reading them. A connect
failure costs one connect per batch. CncRelay.Up() retries the re-bind.
Refs #740
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
I1: the U11 Bits[n] -> Bits[n/32] rewrite was unconditional. The native
runtime now keeps the original element path until the first reply settles the
layout: 0xD3 confirms DWORD addressing (bit n%32); any other reply type (e.g.
a 0xC1 per-element BOOL array) or a refusal of the DWORD index falls back to
Bits[n] and re-reads, and a write settles the layout by a read first, so it can
never decode or write element n/32 of an element-addressed array.
I2: libplctag ErrorNoMatch/ErrorBadDevice no longer fold into NotFound (they
now read as BadConnection: comms, Degraded, LastSuccessfulRead preserved).
ErrorNotImplemented - and the native runtime's own pre-send refusals - raise
AbCipLocalRefusalException: BadNotSupported, no health, LastSuccessfulRead NOT
advanced, no backoff record, not reachable for the probe or Test Connect.
M1: the bit RMW's parent read/write status words follow the health contract
(refusal: per-tag Bad + Warning; comms: evict the parent + Degraded).
M2: device Unsupported read refusals return Refused (advance
LastSuccessfulRead); device write refusals call RecordWriteAnswered (not the
pre-send native type gate).
M3: a good write clears a Degraded a write comms fault recorded (a read-side
Degraded is still left for the read path).
M4: a superseded init throws AbCipInitializationSupersededException (not an
OCE); ShutdownAsync stamps Unknown only if no newer init published meanwhile.
M5: the sync-Dispose timing assert is 2 s against a 4 s probe read; the
unencodable-array test asserts health.
Refs #737
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
- IMPORTANT: a successful probe records the PLC's ADS state; a PLC not in Run
keeps the driver Degraded with 'PLC in {state}' while LastSuccessfulRead
still advances (the device answered). RecordDeviceAnswered never restores
Healthy while any device is out of Run.
- Health is per device, rolled up worst-of: a comms fault is remembered on the
device it was seen on and only that device answering clears it (device A
answering no longer clears device B's fault).
- Refused (non-comms) dead registrations back off 30 s doubling to 10 min and
are re-armed by a symbol-version change or retried by the reconnect replay;
comms-class failures keep the every-tick retry. A retry whose failure class
changes republishes the tag's status, once.
- Bit-RMW gates are kept across generations and teardowns (never cleared).
- ShutdownAsync honours its CancellationToken: it stops waiting, finishes the
bookkeeping and throws OperationCanceledException.
- Remarks on why a superseded InitializeAsync throws OperationCanceledException.
- REAL / LREAL values (scalar or array element) outside the target range are
OverflowException -> BadOutOfRange instead of being written as Infinity.
- String / array write encoding factored into AdsTwinCATClient.PlanStringWrite
/ PlanArrayWrite; the fake runs them so a driver-level test covers the real
encode path against a fake resolved symbol.
- Timing-fragile tests use condition waits / measured probe-tick windows; the
dispose-during-shutdown test asserts ordering with a 1 s bound.
Refs #739
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
Against focas-mock:
- H15: a local TCP relay in front of the shared mock takes "the CNC" away and brings it
back without stopping the fixture. A FIXED-only driver goes Degraded with
LastSuccessfulRead frozen and its value Bad, then returns to Healthy with Good values
(the positive control).
- H20: the mock answers cnc_rdalmmsg2 in the 80-byte legacy layout. Nineteen alarms
(1,520 B = 20 x 76) now decode as the 19 seeded alarms; the old length test gives 20,
verified red. A 3-alarm reply is the control.
Refs #740
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
I1: Task.WhenAll waits for the slowest device, so concurrency alone still let a device
that accepts TCP and then stalls cost (its tag count x call timeout) per batch. After the
first timeout, transport failure or comms-class status on a device, its remaining tags in
the batch now fail BadCommunicationError immediately, the same as the coalescer's
FailMembers, which now also stops after a failed range. FIXED: tags are still served
from the cache. A malformed address is BadNodeIdUnknown and does not count as a link
failure. Test: a 10-tag stalled device beside a healthy one completes in under 3 call
timeouts with the healthy value Good. The P9 test now also asserts per-client read
counts and that two reads overlapped across devices.
Minors:
- 1: a superseded init releases its table only if it was never published (flag).
- 2: a fixed-tree refusal credits LastSuccessfulRead; a value-path refusal after a comms
fault restores Healthy.
- 5: alarm/fixed/refusal health is reset inside the publish lock, after the generation
check.
- 6: FocasFixedTreeHealthTests wait on served-failure/refusal counters, not wall-clock.
- 8: data-path health writes (reads, coalescer, writes, poll errors, refusals) carry the
generation they started under and are dropped once a lifecycle call has moved on. Each
write is a check-and-set under the lifecycle lock.
Also adds a unit case where 20 vendor records with type 0 and empty messages stay vendor.
Refs #740
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
Integration cases (both transports, skipped when the fixture is unreachable):
- H10: a typo'd probe tag leaves the host Running and a cold data tag created
after many probe ticks still reads Good;
- H1/L4: a missing tag reads BadNodeIdUnknown every poll beside a Good sibling,
the driver stays Healthy and LastSuccessfulRead advances even when only the
refused tag is read;
- U10 (AB_SERVER_ALLOW_WRITES=1): an int[16] written to TestArray (DINT[16])
reads back element for element through a fresh driver; a 15-element write is
BadOutOfRange.
Not run here: the 10.100.0.35:44818 fixture was down during this lane (Wave 4).
Refs #737
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
F10 follow-through: removing IDisposable outright broke a synchronous
drv.Dispose() call site outside this lane (Runtime.Tests
AbCipAlmaNativeAlarmEndToEndTests). The sync Dispose() is back, but it starts
the same teardown as DisposeAsync and returns instead of parking the caller on
DisposeAsync().AsTask().GetAwaiter().GetResult(); a background fault is
logged. The runtime still takes the IAsyncDisposable path (preferred, never
both).
Refs #737
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
L4 evidence over the real native runtime and a fake CIP target: a renamed tag
that is the device's only lease holder is created once and Forward-Opened once
across five polls, with no Forward Close, every poll BadNodeIdUnknown and the
driver Healthy.
Refs #737
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
P11: AbCipUdtReadPlanner called AbCipUdtMemberLayout.TryBuild(parent.Members)
for every member reference on every poll - O(members^2) per parent per tick,
a dictionary allocation each time. GetOrBuild caches the layout (including a
"not groupable" verdict) in a ConditionalWeakTable keyed by the member list's
identity, which is immutable for the life of the tag table; a re-init's new
lists replace the entries and the old ones are collected with them.
Refs #737
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
U10 (user decision: implement array encode now): config, the AdminUI and
discovery all advertised array tags Operate-writable, but both runtimes encoded
a scalar - an int[] threw InvalidCastException (BadTypeMismatch AND Degraded),
a scalar wrote element 0 natively, and libplctag re-sent its whole last-read
buffer with element 0 patched (stale elements 1..n-1).
- AbCipArrayCodec encodes count elements little-endian at the element width,
CONVERTING each element (ScadaBridge writes int[] to INT arrays; overflow is
BadOutOfRange, unconvertible BadTypeMismatch, both before anything is sent).
- The driver checks the shape before any runtime exists: not a list ->
BadTypeMismatch, length != elementCount -> BadOutOfRange, BOOL/STRING/
structure element types -> BadNotSupported; and, before sending, a controller
buffer that is not width x count -> BadTypeMismatch. Refusals warn once and
write no health.
- Native: ONE Write Tag of count elements with the controller's type code (the
client fragments a large one); libplctag: the codec's bytes copied into the
elem_count-sized buffer, refused TooSmall if it does not fit.
- IAbCipTagRuntime.EncodeArray (default: NotSupportedException).
Real-controller proof is a hardware userGate (see the lane report recipe).
Refs #737
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
Native-subscribe isolation of an unknown symbol, LastSuccessfulRead advance
from pushes alone, a WORD bit write flipping exactly one bit (bit 16
refused), a whole-array REAL write round-trip (length mismatch refused) and a
STRING(80) write round-trip (overflow refused). Every writing case restores
the seed it touched. Skipped without the TwinCAT XAR fixture.
Refs #739
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
Against the focas-mock fixture: the fixed-tree loop is running and reads are in flight
while the driver re-initialises five times. No reader throws and reads keep returning
Good. After shutdown, a fresh driver still connects and reads.
Refs #740
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
U11: a scalar BOOL authored over Bits[n] requested element n and decoded
"any of bits 0-7 of the reply set", so Bits[n] read Good with the subscript
ignored. A Logix BOOL array is stored as DWORDs (0xD3) and its element segment
addresses them, so the native runtime now requests DWORD n / 32 and decodes bit
n % 32 when the controller answers 0xD3 (a plain BOOL reply still decodes its
byte). libplctag exposes no type code and so cannot say which DWORD it read: a
4-byte reply for such a tag is refused BadNotSupported (warned once) instead of
publishing a wrong value as Good. Real-controller proof is a hardware gate.
Refs #737
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
Applies the driver-lane health contract to the value path. Every non-Good read status used
to write Degraded on every poll, so one vacant macro (BadNoData), one EW_NUMBER address
(BadOutOfRange) or one fractional macro on an integer tag made a reachable CNC look sick
forever. Now:
- a comms-class status (BadCommunicationError / BadInternalError (EW_HANDLE) / BadTimeout)
still degrades, with LastSuccessfulRead preserved;
- any other non-Good status is a refusal: the tag reads Bad, one Warning is logged per tag
(re-armed when it next reads Good, cleared at init), driver state is untouched, and
LastSuccessfulRead advances because the CNC answered (CAS, since devices now read
concurrently);
- a write refused with NotSupportedException no longer degrades the driver.
Refs #740
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
The poll engine already builds a per-cycle batch; TwinCAT now forwards it as
OnDataChangeBatch, so DriverInstanceActor gets one message per poll cycle
instead of one per changed tag. Because the actor subscribes ONLY the batch
event of a batch-capable driver, every native-path data change (pushes, the
BadNodeIdUnknown / refusal / unavailable snapshots) is raised through a single
RaiseDataChange that fires both the per-tag event and a fresh one-item batch.
Refs #739
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
Program.cs binds ScriptingOptions from Scripting:* once, clamps every
numeric knob through ScriptingOptions.Sanitized (logging a Warning per
adjustment) and registers the one instance. It now reaches all three
script seams: RoslynVirtualTagEvaluator, the scripted-alarm engine
built in DriverHostActor (new trailing Props parameter, wired in
WithOtOpcUaRuntimeActors) and every Calculation driver (node options
as the base, per-driver config keys override one knob on a copy).
ScriptRunGuard sanitizes again in its ctor and computes the stuck
threshold with a saturating multiply, so an absurd
StuckOrphanQuarantineFactor can no longer throw OverflowException on
a refused run.
Refs #731#734
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
- Device and tag tables are build-and-swap: InitializeAsync builds a fresh
generation and publishes it by one swap under a lifecycle lock, then
releases the replaced generation; teardown swaps in empty tables. A
retained poll loop never sees a table mid-Clear (it used to read
_tagsByRawPath while a re-init only ever added to it), and each device
set is released by exactly one caller.
- A lifecycle generation makes an InitializeAsync overtaken by a shutdown
(or a newer init) release what it built instead of installing it - the
Lane A abandoned-init-overlaps-shutdown case.
- ShutdownAsync joins all probe loops together within 2 s (it awaited each
unbounded - a probe wedged in the blocking ADS Connect hung the actor's
teardown) in parallel with the poll-engine dispose, the whole bounded at
4.5 s; DisposeAsync may run concurrently and returns at once. A connect
that completes on a released device disposes its client.
- Releasing a generation disposes its native registrations, so a direct
re-init no longer leaves live notifications bound to dead DeviceStates.
- Connect gates and RMW semaphores are no longer disposed under in-flight
users (no kernel handle is ever allocated); a fault on a released device
is not recorded as driver health.
- The notification channel counts DropWrite overflows
(ITwinCATClient.DroppedNotificationCount); the probe tick warns with the
delta. A queued value whose registration was disposed is purged in the
client dispatch loop and dropped driver-side for any client.
Refs #739
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
H19: Format/InvalidCast/Overflow on a client value never touched the wire but
latched Degraded; a good write set Healthy and so undid a Degraded the poll
loop had just recorded for other tags (the batch read path is worst-wins for
exactly this reason).
- The three conversion failures map to BadTypeMismatch/BadOutOfRange with a
once-per-tag Warning and no health write (AbLegacy's rule).
- A good write (scalar or bit RMW) advances LastSuccessfulRead only - the
device answered - and leaves the state alone.
- A write comms fault (thrown, or a non-refusal status word, which used to
write no health at all) is Degraded with LastSuccessfulRead preserved and
never downgrades Faulted.
Refs #737
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
ParseAlarms took the 76-byte vendor layout whenever Length % 76 == 0, so a legacy 80-byte
reply of exactly 19 records (1,520 B = 20 x 76) decoded as 20 garbage vendor records.
The response block carries no record count (its 16-byte header is length/class/path/
command/rc/payload length), so the layout is chosen from what is known: the record count
the request asked for (a reply never holds more), then each layout's field invariants on
every record. For legacy records, the int32 type/axis/length must fit a short and the
length must be at most 64. For vendor records, the i16 length must be at most 64. If both
still fit, the layout whose declared lengths match the decoded text wins. Vendor stays the
default when both readings are equally plausible, and unambiguous lengths are unchanged.
Refs #740
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
H17: the .n read-modify-write hard-coded a DINT parent. On an INT or SINT host
(both legal in Logix, and reads of Flags.3 there already worked) the DINT
decode of a 2-byte buffer threw OutOfBounds, the generic catch evicted the BIT
tag's (non-existent) runtime and reported BadCommunicationError + Degraded.
The parent width now comes from the parent read's size (1 SINT / 2 INT /
4 DINT / 8 LINT; unknown keeps the DINT assumption). Narrow hosts use unsigned
arithmetic so a set top bit encodes without overflow; a bit past the host's
width is BadOutOfRange and a non-integer width BadTypeMismatch, both refused
before anything is written, warned once, no health write. A transport failure
in the RMW now evicts the parent runtime it actually used. Native end-to-end:
an INT host is written as ONE INT (type 0xC3, 2 bytes).
Refs #737
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
The handle-recycle loop disposed the device client with no gate. It could null a client a
concurrent EnsureConnectedAsync had just installed (orphaning a live two-socket session),
or dispose one a poll was mid-read on (ObjectDisposedException -> BadCommunicationError +
Degraded on every recycle interval).
The recycle now takes the device's ConnectGate, detaches the client, and disposes it via
SynchronizedFocasClient.DisposeWhenIdleAsync, which waits (bounded by the call timeout plus
slack) for ops that already hold the client. The gate stays held through the drain, so no
fresh session opens beside the old one.
SynchronizedFocasClient no longer disposes its call gate. Releasing a disposed semaphore
threw out of reads that had otherwise completed. Ops that reach a disposed client now get
ObjectDisposedException and are never run on the dead socket.
Refs #740
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
P8: on the native transport the bounded-parallel read window is also the cap
on services per Multiple Service Packet (the device's shared scheduler packs
whatever is queued, within the connection's request/reply byte budget), so the
default 8 cost a 1000-tag controller ~125 round trips per poll instead of ~10.
The effective window (AbCipDriver.ReadWindow) is now max(64, option) when the
native tag factory serves reads; libplctag and injected factories keep the
option exactly. Option doc + AdminUI help text updated (Razor: Wave 4 live
check).
P7 addendum: a work item now takes its window slot only after its runtime
exists. A cold create queues on its device's single-flight connect gate, and
holding a slot there let one dead device's backoff-expiry attempt occupy the
whole window for a full Timeout, stalling every other device's reads.
Refs #737
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
ReadAsync walked the whole batch sequentially, so one SLOW CNC (TCP-accept-then-stall,
the live 31i-B case) cost Timeout per tag per poll while no other device was read.
ReadAsync now resolves every reference against one table snapshot, buckets the rest by
device and reads the devices with Task.WhenAll; each device's tags still go in order on
its own serialised socket (the PMC coalescing pre-pass runs per device, first). Results
land at their own indices.
Also precomputes each device's fixed-tree key prefix (it was built per reference, twice
per poll).
Refs #740
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
Found by the H13 stress test (200 re-inits under a concurrent reader): a read
that resolved the device just before the table swap could cold-create a
runtime into the retired state after its teardown had disposed it (leaked
native handle / lease), and could hit a per-tag SemaphoreSlim the teardown had
disposed, which the generic catch reported as a comms fault (Degraded).
- DeviceState.Retire marks the state retired before disposing handles; each
handle is removed-then-disposed exactly once. A creator re-checks the flag
after its TryAdd (fenced, Dekker-paired with Retire) and disposes the orphan.
- A failure on a retired device is the teardown's doing: BadCommunicationError
for that one call, no evict, no health signal.
- Per-tag/RMW gates are no longer disposed (async-only waits hold no handle),
matching the ConnectGate rationale.
Refs #737
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
H10: the probe loop recorded EVERY exception - including the controller
answering NotFound for a typo'd or download-deleted Probe.ProbeTagPath - as a
Forward-Open failure. At a 5 s tick against a 30 s backoff cap ShouldAttempt
was never true again, so every cold or evicted data tag on a reachable device
read BadCommunicationError indefinitely and the host showed Stopped.
The probe now decides the backoff verdict and the host state separately:
- a device refusal (thrown or as a status word) is backoff success + host
Running + one Warning per device naming the probe tag; an initialised probe
runtime is kept so its lease is not re-opened every tick;
- a malformed probe tag name (AbCipTagConfigurationException) never reached
the device: no backoff signal, no host transition, one Warning;
- a genuine transport failure is unchanged (backoff failure, host Stopped).
Refs #737
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
FocasDataType.String was authorable on any address, but no area read returns text: PMC
fell through to a byte read, PARAM to Int32, MACRO to a double, and the String node
received a boxed number at Good.
One rule, FocasTagDefinitionFactory.DescribeDataTypeMismatch, now backs every path:
- FromTagConfig rejects the pair, so the driver skips + reports it (BadNodeIdUnknown,
never a Good number) and Inspect names the reason at deploy;
- FocasTagConfigModel.Validate refuses it on the typed fields;
- the AdminUI editor only offers String where it is readable and shows the rule's text
inline (kept visible for a loaded blob that already carries it);
- the CLI read/subscribe/probe/write commands refuse it at the boundary.
String stays valid on FIXED: paths (Identity/Program name/mode text) and is ignored on
ALARM: tags; an unparseable address keeps its own diagnosis.
Razor change (FocasTagConfigEditor.razor) needs the Wave 4 live check.
Refs #740
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
Array tags were advertised writable but every write threw InvalidCastException
in ConvertForWrite (reported BadTypeMismatch); STRING writes went through the
Beckhoff marshaller with no length check against STRING(n) and the host's
ANSI code page, which the read side deliberately avoids.
- Array write: TwinCATArrayCodec.ToWriteElements converts exactly ArrayLength
elements to the declared type (CLR lists convert - ScadaBridge writes int[]
to Int16 nodes; a length mismatch or out-of-range element is BadOutOfRange, a
scalar value BadTypeMismatch) before any wire traffic; the ADS client plans
the layout from the resolved PLC array (TwinCATTypeGuard.CheckArray, as the
read does), encodes with TwinCATArrayCodec.Encode - the exact inverse of
Decode - and writes the raw bytes (new ITwinCATClient.WriteArrayAsync).
- STRING / WSTRING write: encoded at the PLC's declared width by
TwinCATStringCodec.EncodeString/EncodeWString (Windows-1252 or UTF-8 per
target, NUL-padded, strict: an over-long value or unrepresentable character
is OverflowException -> BadOutOfRange) and written as raw bytes.
- TwinCAT CLI read/write gain --array-length (+ --separator) for the hardware
gate.
Refs #739
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
The fixed-tree loop swallowed every failure at Debug and never touched health, so a
driver serving only FIXED: tags (Identity/Axes/Program/Status, the typical FOCAS shape)
read Healthy on /hosts with every node Bad and the #527 watchdog could never fire.
The fixed tree is now a third health path beside the value and alarm paths, combined in
GetHealth (worst state, latest LastSuccessfulRead):
- an answered bootstrap / axis pass clears the device's failure and advances
LastSuccessfulRead;
- a transport failure degrades the driver once the device has been silent past the
same staleness budget that turns its values Bad (from its last answer, or from loop
start when it never answered), with LastSuccessfulRead frozen;
- a CNC refusal (non-OK rc) is not a comms loss: it clears the failure and credits nothing.
Refs #740
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
The bit write read and wrote the parent word as a 32-bit UDInt with no parent
check: a bit beyond a 16-bit parent was written into neighbouring bytes, and a
signed parent with its sign bit set read back >= 2^31, so the checked
conversion turned any bit write into BadOutOfRange.
The write now goes through ITwinCATClient.WriteBitAsync: the ADS client
resolves the parent symbol, checks the bit against it (TwinCATBitAccess.
CheckParent, as the notification path already did), reads exactly
parent.ByteSize raw bytes, flips one bit (TwinCATBitAccess.ApplyBitWrite) and
writes the bytes back by index group/offset or variable handle. A bit beyond
the parent is BadOutOfRange, a non-integer parent BadTypeMismatch, a short
parent read BadCommunicationError (never written back), all without a health
write. The per-parent RMW lock stays in the driver.
Refs #739
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
H1/L4: one classification (AbCipRefusals.IsDeviceRefusal) of the statuses
that prove the controller answered - NotFound, OutOfBounds, NotAllowed,
TooLarge, TooSmall, TypeMismatch, Unsupported - shared by the data path, the
Test-Connect probe (IsReachableStatus widened) and the native runtime.
- A refused read/write (thrown or as a status word) is per-tag Bad with a
once-per-tag Warning, keeps the runtime (no evict, so no lease/Forward-Open
churn for a sole lease holder), writes no Degraded and, since the device
answered, advances LastSuccessfulRead without touching the state.
- A refused cold create records the backoff as reachable, so siblings are no
longer throttled for up to 30 s by one Arr[999].
- The native runtime completes InitializeAsync on any refusal (it used to on
TypeMismatch/Unsupported only) and reports it on every later read.
- A refused READ of NotAllowed reads BadNotReadable, not BadNotWritable.
- Test Connect names the refusal ("probe tag refused: OutOfBounds").
0x1C/0x20/0xFF-0x2104 still fold into BadReply inside Driver.Ab.Transport
(Lane K follow-up); they remain comms faults until mapped there.
Refs #737
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
The capability matrix admits #0..99999 on 30i/31i/32i (and anything on Unknown), and
the FOCAS/2 request block has always carried 32-bit arguments, but WireFocasClient cast
every number to short: MACRO:99999 asked the CNC for #-31073 and published that variable
at Good under the authored tag. FocasWireClient's macro/parameter reads, WireMacro.Number
and WireParameter.DataNumber are now int; the request blocks come from MacroRequest /
ParameterRequest builders (byte-identical to the live 31i-B capture for #500).
Same class on PMC: a range whose last byte passes 65535 (Unknown series admits it) is now
refused BadOutOfRange instead of wrapping onto a different 16-bit address.
The wire client is in-process (the other end is the CNC itself), so this is not a
cross-repo contract change. Whether a real 30i honours cnc_rdmacro Arg1 > 32767 is the
hardware userGate.
Refs #740
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
CompleteRead logged a Warning for every non-Good status on every poll and
latched Degraded for all of them. Now a bad tag warns once per bad episode
(re-armed when it reads Good, and on re-initialise), a comms-class status
(BadCommunicationError / BadTimeout) degrades with LastSuccessfulRead
preserved, and any other status - the device answered and refused this tag -
advances LastSuccessfulRead with no state change. Read-path exception
handlers now go through MarkCommsFault, so they never downgrade Faulted.
Refs #739
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
Joseph Doherty