docs(phase4): Modbus Int64/UInt64, FOCAS fail-fast+scaling, Historian Total+dead-letter cap

2026-06-16 05:47:04 -04:00
parent 88d9e3b1a8
commit f9b38c0a61
4 changed files with 58 additions and 8 deletions
@@ -116,3 +116,4 @@ is reproduced in [docs/v2/driver-specs.md §2](../v2/driver-specs.md).
 - **Wrong-endian readings are silently plausible.** A byte-order misconfiguration produces a wrong number, not a Bad quality code — surface byte-order mismatches as data-validation alerts, not status codes (see [docs/v2/driver-specs.md §2](../v2/driver-specs.md)).
 - **`WriteOnChangeOnly` + write-only tags** — the suppression cache is only invalidated by a read that returns a divergent value. A tag that is never subscribed/polled never refreshes its cache entry, so a re-asserted value can be suppressed indefinitely. Subscribe every tag that needs deterministic re-writes, or leave the option off.
 - **Auto-prohibited ranges** are visible via `GetAutoProhibitedRanges` and logged on first occurrence / on clear — use them to find protected register holes in a device's map.
+- **Int64 / UInt64 OPC UA node DataType** — tags declared with `DataType: Int64` or `DataType: UInt64` advertise the correct OPC UA scalar type (`Int64` / `UInt64`) on their node. Values outside the 32-bit range are preserved end-to-end; the wire codec (4-register read/write) was already correct before this fix.