Pre-#150 a coalesced read failure recorded the FULL failed range as permanently prohibited. Healthy registers around the actual protected register stayed in per-tag mode forever (until ReinitializeAsync). The re-probe loop shipped in #151 retried the whole range as a single block, which would either succeed (clearing everything) or fail (changing nothing). Post-#150 the re-probe loop bisects multi-register prohibitions: - _autoProhibited refactored from Dictionary<key, DateTime> to Dictionary<key, ProhibitionState> where ProhibitionState carries LastProbedUtc + SplitPending. Multi-register prohibitions enter with SplitPending=true; single-register prohibitions enter with SplitPending=false (already minimal). - ReprobeLoopAsync delegates the per-pass work to RunReprobeOnceForTestAsync (also exposed for synchronous test driving). Each entry routes to BisectAndReprobeAsync (split-pending + multi-reg) or StraightReprobeAsync (single-reg / non-split-pending). - Bisection: split (start, end) at mid = (start+end)/2. Try (start, mid) and (mid+1, end) as separate coalesced reads. Each FAILED half re-enters the prohibition map with SplitPending = (its end > its start). SUCCEEDED halves vanish, freeing the planner to coalesce across them on the next scan. - Convergence: log2(span) re-probe ticks pin the prohibition to the actual single offending register(s). For a 100-register block with one protected address that's ~7 ticks. Tests (3 new ModbusCoalescingBisectionTests): - Bisection_Narrows_Multi_Register_Prohibition_Per_Reprobe — 11 tags 100..110 with protected address 105. After 4 re-probe passes the prohibition collapses from (100..110) → (100..105) → (103..105) → (105..105). - Bisection_Clears_When_Both_Halves_Are_Healthy — transient failure scenario; protection lifted before re-probe; both bisection halves succeed and the parent vanishes entirely. - Bisection_Splits_Into_Two_When_Both_Halves_Still_Fail — TwoHoleTransport with protected addresses 102 + 108 in the same coalesced range. After bisection both halves still fail (each contains one of the protected addresses); the prohibition map grows to 2 entries. 236 + 3 = 239 unit tests green. Solution build clean.
8.6 KiB
8.6 KiB