Merge remote-tracking branch 'origin/master' into fix/trx-skip-reporting

.github/workflows/v2-ci.yml

@@ -1,7 +1,6 @@
 # CI for the v2 branch — runs on every push + PR to the v2-akka-fuse / master
-# branches. Layered into two jobs:
-#   build           dotnet restore + build (fast feedback on compile errors)
-#   unit-tests      the WHOLE solution minus the env-gated tiers (self-maintaining)
+# branches. One job restores and builds once, then tests the WHOLE solution
+# minus the env-gated tiers (self-maintaining).
 #
 # Skips E2E (Category=E2E) and LiveIntegration (needs a real gateway/PLC/VPN) — both
 # are env-gated tiers with no hosted-runner fixtures. (The skip-gated *.IntegrationTests
@@ -20,38 +19,35 @@ on:
     branches: [v2-akka-fuse, master]
   workflow_dispatch: {}
 
+# #707: one active run per repository across push/PR triggers. Gitea 1.26 supports
+# workflow concurrency; newer pending runs can supersede an older pending run.
+concurrency:
+  group: lmxopcua-v2-ci
+  cancel-in-progress: false
+
 env:
   DOTNET_NOLOGO: "1"
   DOTNET_CLI_TELEMETRY_OPTOUT: "1"
 
 jobs:
 
-  build:
+  unit-tests:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
       - uses: actions/setup-dotnet@v4
         with:
           dotnet-version: 10.0.x
-      # #606: code-reviews/README.md must be regenerated from the per-module findings.md
-      # files; --check exits non-zero on drift without writing (see REVIEW-PROCESS.md section 5).
+      # #606: regenerated review summary must remain in sync with module findings.
       - name: code-reviews README drift check
         run: python3 code-reviews/regen-readme.py --check
+      - name: TRX skip guard fixtures
+        run: python3 scripts/ci/test-assert-not-all-skipped.py
+      # #707: bound project workers and avoid concurrent NuGet restore work.
       - name: dotnet restore
-        run: dotnet restore ZB.MOM.WW.OtOpcUa.slnx
+        run: dotnet restore ZB.MOM.WW.OtOpcUa.slnx --disable-parallel -m:2
       - name: dotnet build
-        run: dotnet build ZB.MOM.WW.OtOpcUa.slnx --no-restore --configuration Release
-
-  unit-tests:
-    needs: build
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v4
-      - uses: actions/setup-dotnet@v4
-        with:
-          dotnet-version: 10.0.x
-      - name: dotnet restore
-        run: dotnet restore ZB.MOM.WW.OtOpcUa.slnx
+        run: dotnet build ZB.MOM.WW.OtOpcUa.slnx --no-restore --configuration Release -m:2
       # #606: the runner's size is the context every timing-sensitive failure needs and the log never
       # recorded it (load average included: the two Gitea runners may be running jobs side by side).
       - name: runner capacity
@@ -69,14 +65,15 @@ jobs:
       # are unreachable, so they run harmlessly here (and are counted by the skip-gate below).
       - name: dotnet test (whole solution, minus E2E + LiveIntegration)
         # #606: Akka TestKit time dilation for the Runtime + ControlPlane actor suites (read by their
-        # harnesses, tests/Server/*/Harness/TestTimeFactor.cs). This leg runs every test assembly at once
-        # on the runner, and their 2–8 s presence budgets — sized on an idle dev box — failed in a long
+        # harnesses, tests/Server/*/Harness/TestTimeFactor.cs). Their 2–8 s presence budgets
+        # — sized on an idle dev box — failed in a long
         # tail, a different test per run. Dilation only stretches waits: a presence wait still fails if
         # the message never comes, and absence windows get longer (stricter). Local runs stay at 1.
         env:
           AKKA_TEST_TIMEFACTOR: "3"
         run: >
-          dotnet test ZB.MOM.WW.OtOpcUa.slnx --configuration Release --no-restore
+          dotnet test ZB.MOM.WW.OtOpcUa.slnx --configuration Release --no-build
+          -m:1 -p:TestTfmsInParallel=false --settings scripts/ci/ci.runsettings
           --filter "Category!=E2E&Category!=LiveIntegration"
           --logger "trx" --results-directory artifacts/trx
       # 07/S-2 fail-on-skip: a whole-solution run that executed ZERO tests is a masked outage

docs/drivers/S7.md

@@ -198,15 +198,53 @@ Timers are **read-only** this phase; a write attempt returns `BadNotWritable`.
 ### Counter read
 
 **Address**: `C{n}` (e.g. `C0`, `C10`). **DataType must be `Int32`**. The OPC UA node is
-a scalar `Int32` whose value is the current **count** (raw word from the PLC).
+a scalar `Int32` containing the unsigned **raw big-endian word**, widened to `Int32`:
+`(bytes[0] << 8) | bytes[1]`. `S7.Net`'s `Counter.FromByteArray` performs no BCD
+reinterpretation; for example, bytes `01 23` surface as `291`. This describes the
+current decoder, not verified agreement with a PLC's displayed count.
 Counters are **read-only** this phase; a write attempt returns `BadNotWritable`.
 
-> **Known limitation — Counter BCD encoding on S7-300/400**: `S7.Net`'s
-> `Counter.FromByteArray` returns the raw big-endian word without BCD decode.
-> On **classic S7-300/400** the C-area word is BCD-encoded (0–999), so the
-> surfaced value can differ from the actual count on that hardware. S7-1200/1500
-> use IEC/DB counters (plain integers) where the raw word is correct. BCD
-> reinterpretation for legacy C-area is a live-hardware-gated follow-up.
+The S7comm ReadVar **C-area response encoding remains unverified on hardware**.
+PLC instruction representations do not by themselves establish network encoding:
+Siemens documents a binary current value for [L: Load counter](https://docs.tia.siemens.cloud/r/en-us/v21/stl-s7-300-s7-400/stl-mnemonic-s7-300-s7-400/counter-operations-s7-300-s7-400/l-load-counter-s7-300-s7-400)
+and separate `CV` and `CV_BCD` outputs for [S_CD](https://docs.tia.siemens.cloud/r/en-us/v21/lad-s7-300-s7-400/counter-operations-s7-300-s7-400/simatic-counters-s7-300-s7-400/s_cd-assign-parameters-and-count-down-s7-300-s7-400?contentId=reR_xapFX_Ike2opHIvfzg).
+
+IEC counter values stored in DB memory use the **DB address and declared integer
+type**, a different read path from `C{n}`. CPU family alone does not select the
+counter kind or prove its wire representation. In particular, Siemens also lists
+legacy SIMATIC counters for S7-1500 in its [instruction comparison (pages 23–24)](https://cache.industry.siemens.com/dl/files/777/109986777/att_1322640/v1/s7_1500_compare_table_en.pdf?download=true).
+The driver has no counter encoding selector; hardware-faithful counter support
+requires independent raw-response evidence before any interpretation change.
+
+### Counter evidence follow-up (#616)
+
+The existing `S7_1500SpanReadTests` exercises the python-snap7 profile's synthetic
+raw words (`C0 = 4711`, `C7 = 31337`). These are outside the classic SIMATIC count
+range `0..999` documented by S_CD. These expectations describe raw-word handling;
+they do not establish classic counter count semantics. The recorded device-0 run cannot prove nonzero
+numbering. The nonzero test is environment-gated, but its options remain
+`CpuType = S71500`, rack `0`, slot `0`: setting `S7_TIMER_NUMBER_ADDRESSING=1`
+does not configure a classic CPU or make the profile a classic counter gate.
+
+Before claiming hardware validation or closing #616:
+
+- Prepare a separate target-specific semantic gate with the actual CPU type,
+  rack, slot and TSAP/connection settings. Keep the synthetic raw-word profile
+  as its own evidence of the existing decoder contract.
+- Record CPU model/order number, firmware, endpoint, connection settings and
+  driver/S7netplus plus simulator versions where applicable.
+- Observe independent PLC-side current counts and binary/BCD reference outputs
+  for valid classic counts such as `123`, a second distinguishing count (`42`
+  or `999`), and zero. Record the instruction/counter kind and DB reference
+  addresses; do not derive reference values from the driver's output.
+- Capture the actual two-byte S7comm C-area responses alongside those references.
+  Do not infer response bytes from a simulator seed or expected BCD value.
+- Verify several distinct nonzero timer/counter numbers against their independent
+  PLC values and captured requests/responses, and verify the read-only contract.
+
+The raw-byte/count and nonzero-numbering gates remain open. Password/protection
+support inherited from #303/#632 is a separate follow-up, not evidence supplied
+by these counter checks.
 
 ### Deferrals (not yet implemented)
 

scripts/ci/README.md

@@ -0,0 +1,53 @@
+# Whole-solution CI
+
+The `v2-ci` workflow restores, builds and tests in one job so the test step uses
+that job's Release binaries. Restore disables parallel package work; restore and
+build use at most two MSBuild workers. Testing uses one MSBuild worker, disables
+parallel target-framework runs and loads `ci.runsettings`: one VSTest process and
+two xUnit collection workers with conservative scheduling. Assemblies that disable
+parallelization keep that setting.
+
+The workflow retains the E2E/LiveIntegration exclusions, includes SlowUnit, keeps
+Akka's test time factor at three, and requires at least 12,000 executed tests.
+Runner capacity and TRX files remain available for diagnosing failures. These
+limits reduce contention; they do not prove every timing failure has one cause.
+There are no automatic test retries or changed assertion deadlines.
+
+Gitea 1.26 supports the repository-wide `lmxopcua-v2-ci` concurrency group. Only
+one run is active; an active run is not cancelled, but a newer pending run may
+supersede an older pending run. The group does not serialize other repositories
+using the same host.
+
+To reproduce the bounded test leg after restore and Release build:
+
+```bash
+AKKA_TEST_TIMEFACTOR=3 dotnet test ZB.MOM.WW.OtOpcUa.slnx \
+  --configuration Release --no-build -m:1 -p:TestTfmsInParallel=false \
+  --settings scripts/ci/ci.runsettings \
+  --filter "Category!=E2E&Category!=LiveIntegration" \
+  --logger trx --results-directory artifacts/trx
+MIN_EXECUTED=12000 bash scripts/ci/assert-not-all-skipped.sh artifacts/trx/*.trx
+```
+
+The guard uses the existing TRX `Counters/@executed` value for the aggregate
+floor. Its `skipped` diagnostic counts individual `Results/UnitTestResult`
+records whose outcome is `NotExecuted`, using the document's XML namespace.
+Some VSTest reports set summary `notExecuted` to zero even when these records
+are present. Skip records are counted per file, including repeated runs; they
+are not a count of unique test methods and do not affect the executed floor.
+For malformed XML, the diagnostic retains the old summary-counter fallback;
+this guard does not add XML validation to its existing gate policy.
+
+Run the deterministic script fixtures without building or running the solution:
+
+```bash
+python3 scripts/ci/test-assert-not-all-skipped.py
+```
+
+Verified hosted baseline: [Gitea run 975](https://gitea.dohertylan.com/dohertj2/lmxopcua/actions/runs/975)
+completed successfully on 2026-10-13 for commit
+`76bdca90e94e814e06ef10b78271e2b492b2ba32` (merged by PR #711).
+Restore, Release build, README drift check, the serialized whole-solution test
+step, the 12,000-test floor and TRX upload all passed. The floor counted
+14,630 executed tests across 62 TRX files. This baseline predates the individual
+skip-reporting correction; its printed zero skip diagnostic is not skip evidence.

scripts/ci/assert-not-all-skipped.sh

@@ -33,12 +33,31 @@ for f in "$@"; do
     exit 2
   fi
   seen=$((seen + 1))
-  # The trx <Counters .../> element in <ResultSummary> carries executed + notExecuted counts.
+  # Keep the executed-counter floor unchanged; notExecuted is only a fallback
+  # for malformed XML that this guard historically accepted.
   counters="$(grep -oE '<Counters[^>]*/?>' "$f" | head -1)"
   ex="$(printf '%s' "$counters" | grep -oE 'executed="[0-9]+"' | grep -oE '[0-9]+' || true)"
   ne="$(printf '%s' "$counters" | grep -oE 'notExecuted="[0-9]+"' | grep -oE '[0-9]+' || true)"
   ex="${ex:-0}"
   ne="${ne:-0}"
+  # VSTest can emit notExecuted="0" despite individual NotExecuted results.
+  # Count direct Results/UnitTestResult records in the document's namespace,
+  # excluding foreign elements, nested records and escaped diagnostic text.
+  ne="$(python3 - "$f" "$ne" <<'PY'
+import sys
+import xml.etree.ElementTree as ET
+
+try:
+    root = ET.parse(sys.argv[1]).getroot()
+except ET.ParseError:
+    # Skip reporting must not introduce a new malformed-XML gate failure.
+    print(sys.argv[2])
+else:
+    namespace = root.tag.split("}", 1)[0] + "}" if root.tag.startswith("{") else ""
+    results = root.findall(f"{namespace}Results/{namespace}UnitTestResult")
+    print(sum(result.get("outcome") == "NotExecuted" for result in results))
+PY
+)"
   total_executed=$((total_executed + ex))
   total_skipped=$((total_skipped + ne))
   echo "  $(basename "$f"): executed=${ex} skipped=${ne}"

scripts/ci/ci.runsettings

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+<RunSettings>
+  <!-- #707: project scheduling is also bounded by dotnet test -m:1. -->
+  <RunConfiguration>
+    <MaxCpuCount>1</MaxCpuCount>
+  </RunConfiguration>
+  <xUnit>
+    <!-- Preserve each assembly's parallelization opt-out; bound enabled collections. -->
+    <MaxParallelThreads>2</MaxParallelThreads>
+    <ParallelAlgorithm>conservative</ParallelAlgorithm>
+  </xUnit>
+</RunSettings>

scripts/ci/test-assert-not-all-skipped.py

@@ -0,0 +1,108 @@
+#!/usr/bin/env python3
+"""Deterministic subprocess checks for the TRX executed-floor guard."""
+import os
+from pathlib import Path
+import subprocess
+import tempfile
+import unittest
+
+
+SCRIPT = Path(__file__).with_name("assert-not-all-skipped.sh")
+NS = "http://microsoft.com/schemas/VisualStudio/TeamTest/2010"
+
+
+def trx(executed, outcomes, summary_skipped=0, namespace=NS, extra=""):
+    declaration = f' xmlns="{namespace}"' if namespace else ""
+    results = "".join(f'<UnitTestResult outcome="{outcome}"/>' for outcome in outcomes)
+    return (f'<TestRun{declaration}><Results>{results}{extra}</Results>'
+            f'<ResultSummary><Counters total="{len(outcomes)}" executed="{executed}" '
+            f'notExecuted="{summary_skipped}"/></ResultSummary></TestRun>')
+
+
+class SkipGuardTests(unittest.TestCase):
+    def setUp(self):
+        self.directory = tempfile.TemporaryDirectory(prefix="trx-skip-fixtures-")
+        self.addCleanup(self.directory.cleanup)
+        self.root = Path(self.directory.name)
+
+    def write(self, name, content):
+        path = self.root / name
+        path.write_text(content, encoding="utf-8")
+        return path
+
+    def run_guard(self, *paths, minimum=None):
+        env = os.environ.copy()
+        env.pop("MIN_EXECUTED", None)
+        if minimum is not None:
+            env["MIN_EXECUTED"] = str(minimum)
+        return subprocess.run(["bash", str(SCRIPT), *map(str, paths)], env=env,
+                              text=True, capture_output=True, check=False)
+
+    def assert_report(self, result, status, executed, skipped, files=1):
+        self.assertEqual(status, result.returncode, result.stdout + result.stderr)
+        self.assertIn(f"files={files} executed={executed} skipped={skipped} ", result.stdout)
+
+    def test_mixed_results_ignore_zero_summary_skip_counter(self):
+        # A summary-only skip count misses the three actual NotExecuted records.
+        path = self.write("mixed.trx", trx(827, ["Passed"] * 827 + ["NotExecuted"] * 3))
+        result = self.run_guard(path)
+        self.assert_report(result, 0, 827, 3)
+        self.assertIn("mixed.trx: executed=827 skipped=3", result.stdout)
+
+    def test_all_skipped_fails_default_floor_but_report_only_passes(self):
+        path = self.write("all-skipped.trx", trx(0, ["NotExecuted"] * 188))
+        self.assert_report(self.run_guard(path), 1, 0, 188)
+        self.assert_report(self.run_guard(path, minimum=0), 0, 0, 188)
+
+    def test_zero_tests_fails_default_floor_but_report_only_passes(self):
+        path = self.write("zero.trx", trx(0, []))
+        self.assert_report(self.run_guard(path), 1, 0, 0)
+        self.assert_report(self.run_guard(path, minimum=0), 0, 0, 0)
+
+    def test_agreeing_summary_and_outcomes_are_not_double_counted(self):
+        path = self.write("agreeing.trx", trx(1, ["Passed", "NotExecuted"], 1))
+        self.assert_report(self.run_guard(path), 0, 1, 1)
+
+    def test_outcomes_are_authoritative_when_summary_overstates_skips(self):
+        path = self.write("overstated.trx", trx(1, ["Passed", "NotExecuted"], 9))
+        self.assert_report(self.run_guard(path), 0, 1, 1)
+
+    def test_namespace_path_and_exact_outcome_exclude_decoys(self):
+        extra = ('<Other><UnitTestResult outcome="NotExecuted"/></Other>'
+                 '<foreign:UnitTestResult xmlns:foreign="urn:other" outcome="NotExecuted"/>'
+                 '<Output><Message>&lt;UnitTestResult outcome="NotExecuted"/&gt;</Message></Output>')
+        content = trx(2, ["Passed", "Failed", "NotExecuted", "notexecuted"], extra=extra)
+        # Prefixes on Results/UnitTestResult must work just like the default namespace.
+        content = content.replace('<TestRun ', f'<TestRun xmlns:t="{NS}" ')
+        content = content.replace('<Results>', '<t:Results>').replace('</Results>', '</t:Results>')
+        content = content.replace('<UnitTestResult ', '<t:UnitTestResult ')
+        path = self.write("namespaced.trx", content)
+        self.assert_report(self.run_guard(path), 0, 2, 1)
+
+    def test_unnamespaced_results_remain_supported(self):
+        path = self.write("legacy.trx", trx(1, ["Passed", "NotExecuted"], namespace=""))
+        self.assert_report(self.run_guard(path), 0, 1, 1)
+
+    def test_executed_counter_controls_aggregate_floor_at_boundary(self):
+        # Counters retain authority even when result records disagree with executed.
+        mixed = self.write("floor.trx", trx(12000, ["Passed", "NotExecuted"]))
+        skipped = self.write("skipped.trx", trx(0, ["NotExecuted"]))
+        self.assert_report(self.run_guard(mixed, skipped, minimum=12000), 0, 12000, 2, 2)
+        self.assert_report(self.run_guard(mixed, skipped, minimum=12001), 1, 12000, 2, 2)
+
+    def test_missing_arguments_and_file_keep_exit_two(self):
+        self.assertEqual(2, self.run_guard().returncode)
+        self.assertEqual(2, self.run_guard(self.root / "missing.trx").returncode)
+
+    def test_missing_counters_keeps_existing_exit_one(self):
+        path = self.write("no-counters.trx", '<TestRun><Results/></TestRun>')
+        self.assertEqual(1, self.run_guard(path, minimum=0).returncode)
+
+    def test_malformed_xml_keeps_summary_fallback_and_gate_status(self):
+        path = self.write("malformed.trx", '<TestRun><Counters executed="2" notExecuted="3"/>')
+        self.assert_report(self.run_guard(path, minimum=2), 0, 2, 3)
+        self.assert_report(self.run_guard(path, minimum=3), 1, 2, 3)
+
+
+if __name__ == "__main__":
+    unittest.main(verbosity=2)

src/Drivers/ZB.MOM.WW.OtOpcUa.Driver.S7/S7Driver.cs

@@ -1465,7 +1465,7 @@ public sealed class S7Driver
     {
         // AREA precedence first (before the DataType switch): a Timer (T{n}) decodes its 2-byte
         // S5TIME word to a duration in SECONDS via S7.Net's Timer.FromByteArray (returns double);
-        // a Counter (C{n}) decodes its 2-byte word to a COUNT via Counter.FromByteArray (returns
+        // a Counter (C{n}) exposes its 2-byte RAW WORD via Counter.FromByteArray (returns
         // ushort, surfaced as a non-negative int to match the tag's Int32 type). Routing on Area
         // here is essential: a Timer tag is typed Float64, so letting it fall to the Float64 arm
         // below would ReadDoubleBigEndian over a 2-byte block = garbage/throw. Boxed explicitly so
@@ -1474,11 +1474,12 @@ public sealed class S7Driver
             return (object)global::S7.Net.Types.Timer.FromByteArray(block);
         if (addr.Area is S7Area.Counter)
         {
-            // NOTE: S7.Net Counter.FromByteArray returns the RAW big-endian word ((bytes[0]<<8)|bytes[1]),
-            // NOT a BCD decode. On classic S7-300/400 the C-area word is BCD (0-999), so on that hardware
-            // this raw value can differ from the displayed count; S7-1200/1500 use IEC/DB counters (plain
-            // ints), where it is correct. Surfacing S7.Net's value verbatim is the faithful choice; BCD
-            // reinterpretation for legacy C-area counters is a live-hardware-gated follow-up.
+            // S7.Net Counter.FromByteArray returns the raw big-endian word ((bytes[0]<<8)|bytes[1]),
+            // without BCD reinterpretation. This preserves the raw value, not a verified PLC count:
+            // S7comm C-area response encoding still needs independent raw bytes and PLC-side
+            // count/binary/BCD references (#616). CPU family alone does not prove that encoding.
+            // IEC counter integers in DB memory take the DB type codec, not this C-area path;
+            // S7-1500 also has legacy SIMATIC counters. See docs/drivers/S7.md for the evidence gate.
             return (object)(int)global::S7.Net.Types.Counter.FromByteArray(block);
         }
 

tests/Drivers/ZB.MOM.WW.OtOpcUa.Driver.Historian.Gateway.Tests/GatewayCeilingPagingTests.cs

@@ -197,8 +197,6 @@ public sealed class GatewayCeilingPagingTests : IDisposable
     [InlineData(L - 1, 5000u)]
     [InlineData(L, 5000u)]
     [InlineData(L + 1, 5000u)]
-    [InlineData(Ceiling - 17, 5000u)]
-    [InlineData(Ceiling - 16, 5000u)]
     [InlineData(Ceiling + 1, 5000u)]
     [InlineData(L - 2, 0u)]
     [InlineData(L - 1, 0u)]

tests/Drivers/ZB.MOM.WW.OtOpcUa.Driver.S7.IntegrationTests/S7_1500/S7_1500SpanReadTests.cs

@@ -27,7 +27,15 @@ namespace ZB.MOM.WW.OtOpcUa.Driver.S7.IntegrationTests.S7_1500;
 ///         areas: <b>PASSED</b> — 4 passed, 0 failed, 1 skipped (the device number-addressing test,
 ///         see below). The Timer/Counter batch was served by 4 requests for 7 tags: one DB1 span,
 ///         one 3-item multi-var carrying only the scalars, and one 2-byte area read apiece for
-///         <c>T0</c> (decoded 456.0 s from S5TIME <c>0x2456</c>) and <c>C0</c> (decoded count 4711).
+///         <c>T0</c> (decoded 456.0 s from S5TIME <c>0x2456</c>) and <c>C0</c> (surfaced raw word 4711).
+///     </para>
+///     <para>
+///         <b>Counter evidence limit.</b> The profile's C0=4711 and C7=31337 are synthetic raw
+///         words, outside classic SIMATIC counts 0..999. The device-0 record proves the fixture's
+///         raw-word decode and batching exclusion, not classic count semantics or nonzero
+///         addressing. BuildOptions retains S71500/rack 0/slot 0; a target-specific semantic gate
+///         still needs independent PLC counts and binary/BCD references paired with captured
+///         C-area bytes, CPU model/firmware and connection settings (docs/drivers/S7.md, #616).
 ///     </para>
 ///     <para>
 ///         <b>What the layout buys.</b> The ten tags are positioned so the planner's rules produce a
@@ -73,11 +81,12 @@ namespace ZB.MOM.WW.OtOpcUa.Driver.S7.IntegrationTests.S7_1500;
 ///         returns TM bytes 0..1, and it takes <c>start 80</c> (= 10 × 8) to reach the timer seeded
 ///         at TM byte 10. Device <b>0</b> is the single fixed point of the two conventions
 ///         (<c>0 &gt;&gt; 3 == 2 × 0 == 0</c>), so it is the only device this fixture can pin a
-///         VALUE for, and that is what the mixed batch uses. The spec-correct <c>2 × N</c> cells
+///         VALUE for, and that is what the mixed batch uses. The profile's <c>2 × N</c> cells
 ///         are seeded too and
 ///         <see cref="Timer_and_counter_decode_the_seeded_values_at_their_device_numbers"/> asserts
 ///         them — skipped unless <c>S7_TIMER_NUMBER_ADDRESSING=1</c> declares the endpoint a real
-///         CPU. The device-number offset arithmetic itself stays unit-covered
+///         CPU. This flag is an operator declaration, not hardware evidence.
+///         The device-number offset arithmetic itself stays unit-covered
 ///         (<c>S7ScalarBlockTests</c>, <c>S7SpanReadParityTests</c>).
 ///     </para>
 ///     <para>
@@ -240,7 +249,7 @@ public sealed class S7_1500SpanReadTests(Snap7ServerFixture sim)
             snapshot.StatusCode.ShouldBe(0u, $"'{name}' must be Good");
 
         // (a) Correct decode off real wire. A Timer surfaces as the S5TIME word's duration in
-        // seconds (double) and a Counter as the raw count (int) — two different areas, two
+        // seconds (double) and a Counter as the raw word (int) — two different areas, two
         // different values, two different CLR types, so a read that reached the wrong area or
         // decoded through the wrong arm cannot pass.
         byName["TC_Timer"].Value.ShouldBe(TimerCounterLayout.Device0TimerSeconds);
@@ -280,15 +289,19 @@ public sealed class S7_1500SpanReadTests(Snap7ServerFixture sim)
 
     /// <summary>
     ///     Verifies a Timer and a Counter at NON-zero device numbers decode their seeded values —
-    ///     the assertion the shared fixture cannot serve.
+    ///     the raw-word assertion the shared fixture cannot serve.
     /// </summary>
     /// <remarks>
     ///     Skipped unless <c>S7_TIMER_NUMBER_ADDRESSING=1</c> declares the endpoint a device
     ///     number-addressing CPU, because python-snap7's server is not one: it resolves the TM/CT
     ///     request address as a bit address, so <c>T5</c> reads TM byte 0 rather than TM byte 10
-    ///     (measured 2026-08-17 — see the type remarks). Set the variable alongside
-    ///     <c>S7_SIM_ENDPOINT</c> when pointing this suite at a real S7 CPU seeded to match
-    ///     <c>Docker/profiles/s7_1500.json</c>'s TM/CT areas.
+    ///     (measured 2026-08-17 — see the type remarks). The flag only enables this test;
+    ///     BuildOptions still selects S71500, rack 0, slot 0 and the profile's raw C7 word 31337.
+    ///     It does not configure a classic CPU or prove classic 0..999 count semantics. A separate
+    ///     target-specific gate needs valid counts, independent PLC binary/BCD references and
+    ///     captured C-area bytes, plus CPU model/firmware and connection settings (#616).
+    ///     See docs/drivers/S7.md for the evidence checklist. The skip message below retains the
+    ///     historical fixture instructions; enabling the flag alone does not satisfy this gate.
     /// </remarks>
     [Fact]
     public async Task Timer_and_counter_decode_the_seeded_values_at_their_device_numbers()
@@ -408,12 +421,13 @@ public sealed class S7_1500SpanReadTests(Snap7ServerFixture sim)
     /// <summary>
     ///     The Timer/Counter layouts. Two sets: a mixed batch that provokes all three read shapes at
     ///     once (block span, multi-var, per-tag Timer/Counter), and a device-numbered pair only a
-    ///     real CPU can serve. Addresses map 1:1 to the TM0 / CT0 seeds in
+    ///     device number-addressing endpoint can serve. These synthetic raw-word expectations
+    ///     do not prove classic counter semantics. Addresses map 1:1 to the TM0 / CT0 seeds in
     ///     <c>Docker/profiles/s7_1500.json</c>.
     /// </summary>
     private static class TimerCounterLayout
     {
-        /// <summary>Declares the endpoint a real S7 CPU, which addresses TM/CT by device number.</summary>
+        /// <summary>Operator opt-in for nonzero TM/CT addressing; does not change CPU options or prove encoding.</summary>
         public const string RealCpuEnvVar = "S7_TIMER_NUMBER_ADDRESSING";
 
         /// <summary>
@@ -425,7 +439,7 @@ public sealed class S7_1500SpanReadTests(Snap7ServerFixture sim)
         /// <summary>T0's seed 0x2456 — S5TIME base 2 (×1 s) over BCD 456.</summary>
         public const double Device0TimerSeconds = 456.0d;
 
-        /// <summary>C0's seed — the raw big-endian count word.</summary>
+        /// <summary>C0's synthetic raw big-endian word 4711; not a classic 0..999 count reference.</summary>
         public const int Device0CounterCount = 4711;
 
         /// <summary>
@@ -441,7 +455,7 @@ public sealed class S7_1500SpanReadTests(Snap7ServerFixture sim)
             new("TC_Lone_I16",   "DB1.DBW600", S7DataType.Int16),
             new("TC_Lone_Mk",    "MW10",       S7DataType.UInt16),
             // Timer tags are typed Float64 (decoded to seconds) and Counter tags Int32 (decoded to
-            // a count) — the init guard rejects any other typing. Writable:false is mandatory, not
+            // a raw word) — the init guard rejects any other typing. Writable:false is mandatory, not
             // stylistic: S7TagDefinition defaults Writable to TRUE and the same guard rejects a
             // writable Timer/Counter outright (they are read-only this phase).
             new("TC_Timer",      "T0",         S7DataType.Float64, Writable: false),

tests/Server/ZB.MOM.WW.OtOpcUa.ControlPlane.Tests/Communication/CentralCommunicationActorTests.cs

@@ -1,6 +1,9 @@
 using System.Diagnostics.CodeAnalysis;
 using Akka.Actor;
 using Akka.Cluster.Tools.PublishSubscribe;
+using Akka.Event;
+using Akka.TestKit;
+using Akka.TestKit.Xunit2;
 using Microsoft.EntityFrameworkCore;
 using Shouldly;
 using Xunit;
@@ -680,7 +683,7 @@ public class CentralCommunicationActorTests : ControlPlaneActorTestBase
 
     /// <summary>Counts contact loads and fails the first <c>failFirst</c> of them.</summary>
     private sealed class CountingDbFactory(
-        IDbContextFactory<OtOpcUaConfigDbContext> inner, int failFirst = 0)
+        IDbContextFactory<OtOpcUaConfigDbContext> inner, int failFirst = 0, Action<int>? onLoad = null)
         : IDbContextFactory<OtOpcUaConfigDbContext>
     {
         private int _calls;
@@ -689,7 +692,9 @@ public class CentralCommunicationActorTests : ControlPlaneActorTestBase
 
         public OtOpcUaConfigDbContext CreateDbContext()
         {
-            if (Interlocked.Increment(ref _calls) <= failFirst)
+            var call = Interlocked.Increment(ref _calls);
+            onLoad?.Invoke(call);
+            if (call <= failFirst)
                 throw new InvalidOperationException("ConfigDb unreachable at boot");
             return inner.CreateDbContext();
         }
@@ -747,31 +752,51 @@ public class CentralCommunicationActorTests : ControlPlaneActorTestBase
     [Fact]
     public void Bootstrap_retries_stop_once_the_gate_is_published()
     {
-        // The provider throws on PreStart (call 1) and on the first load's resolve (call 2), which
-        // schedules a 1 s retry. A manual refresh then publishes while that retry is still PENDING;
-        // stop-on-publish must cancel it. Without the cancel the timer fires, loads again and
-        // republishes (loads == 3, publications == 2).
+        // Freeze time only for this fact: the cluster harness and every other retry test retain
+        // their real scheduler. gRPC mode needs neither cluster membership nor pub-sub here.
+        using var local = new TestKit(@"akka {
+            loglevel = INFO
+            scheduler.implementation = ""Akka.TestKit.TestScheduler, Akka.TestKit""
+        }");
+        var scheduler = (TestScheduler)local.Sys.Scheduler;
+        var loads = local.CreateTestProbe();
+        var barrier = local.CreateTestProbe();
+        local.Sys.EventStream.Subscribe(barrier.Ref, typeof(UnhandledMessage));
         var inner = NewInMemoryDbFactory();
         SeedGrpcCluster(inner, "C1", ("host-a:4053", "host-a", 4056, true, false));
-        var factory = new CountingDbFactory(inner);
+        var factory = new CountingDbFactory(inner, onLoad: n => loads.Ref.Tell(n));
         var psk = new RecordingPskProvider();
         var calls = 0;
 
+        // PreStart and the first contact load fail resolution. The latter registers a retry.
         IMeshPskProvider? PskFactory() =>
             Interlocked.Increment(ref calls) <= 2 ? throw new InvalidOperationException("race") : psk;
 
-        var actor = Sys.ActorOf(CentralCommunicationActor.Props(
+        var actor = local.Sys.ActorOf(CentralCommunicationActor.Props(
             factory, GrpcMode(), () => null, () => new RecordingDialer(), PskFactory,
             bootstrapRetryInterval: TimeSpan.FromSeconds(1)));
+        // A mailbox barrier also waits for PreStart to register the zero-delay periodic tick.
+        var marker = new object();
+        actor.Tell(marker);
+        barrier.ExpectMsg<UnhandledMessage>(TimeSpan.FromSeconds(5)).Message.ShouldBeSameAs(marker);
+        scheduler.Advance(TimeSpan.Zero);
+        loads.ExpectMsg(1, TimeSpan.FromSeconds(5));
+        local.AwaitCondition(() => Volatile.Read(ref calls) == 2, TimeSpan.FromSeconds(5));
 
-        // Positive control: the failed first resolve happened, so a retry is pending.
-        AwaitCondition(() => Volatile.Read(ref calls) >= 2, TimeSpan.FromSeconds(5));
-        Thread.Sleep(100);
-        actor.Tell(new CentralCommunicationActor.RefreshContacts());
-        AwaitCondition(() => psk.KnownClusterPublications.Count >= 1, TimeSpan.FromSeconds(5));
+        // This mailbox marker is handled after the failed ContactsLoaded handler returns.
+        // Unlike observing the provider call alone, it proves retry registration is complete.
+        actor.Tell(marker);
+        barrier.ExpectMsg<UnhandledMessage>(TimeSpan.FromSeconds(5)).Message.ShouldBeSameAs(marker);
 
-        Thread.Sleep(2500);
+        local.EventFilter.Info(contains: "Known-cluster gate published").ExpectOne(
+            TimeSpan.FromSeconds(5), () => actor.Tell(new CentralCommunicationActor.RefreshContacts()));
+        loads.ExpectMsg(2, TimeSpan.FromSeconds(5));
 
+        // Cross the pending retry deadline, leaving the 60-second periodic tick untouched.
+        // LoadContactsFromDb uses Task.Run, so observe its boundary for the original absence
+        // budget rather than asserting before a mistakenly retained retry can start its read.
+        scheduler.Advance(TimeSpan.FromMilliseconds(2500));
+        loads.ExpectNoMsg(TimeSpan.FromMilliseconds(2500));
         factory.Calls.ShouldBe(2);
         psk.KnownClusterPublications.Count.ShouldBe(1);
     }