- HardwareGateGuardTests: only StringWriteGateTests may name a write path in HardwareGate/; the
allow-list is exactly the two Z-35162 (10.209.70.160) STRING tags; the opt-in, the (host, tag)
check and the AB_DIFF_ENDPOINT refusal are present. Proven red by a WriteAsync mutation.
- StringWriteGateTests: allow-list entries are (host, tag); any other endpoint is refused; skips
while AB_DIFF_ENDPOINT is set, like IntegrationWriteGate.
- AbCip.md #566: the close happened somewhere in the 16-60 s window; RST vs FIN not captured.
Claude-Session: https://claude.ai/code/session_01Ef2ozxS7QPanGT8uoATbTe
A. #566 on a real CompactLogix (Z-35162, read-only): a class-3 connection idled 60 s past its
16 s timeout is closed at the TCP level, not with CIP 0x0107/0x0203; the next request fails on
its write (Broken pipe -> BadConnection) in 9 ms and the one after reopens. The transport already
handles this, so no production behaviour changed; the shape is pinned offline by
CipConnectionTests.A_target_that_resets_an_idle_session_... (FakeEipServer.ResetAllConnections),
proven red with a reconnect-skipping mutation. The diagnostics-only exchange tap now also sees
Forward Open replies (granted RPIs).
B. Native STRING write through the driver on Program:ES03_TemperatureControl._StrTmp: write,
read back, restored byte-exact (user-approved). Array write NOT run: the census's unreferenced
DINT[32] _SEQ_EP arrays are aliased sequencer step registers (raw L5X grep), so none qualifies.
#567 still impossible (a 128 B array / 88 B STRING never fragments).
New env-gated harness: AbCip.IntegrationTests/HardwareGate (IdleConnectionEvidenceTests,
StringWriteGateTests). Docs: gate results (hw5 section + raw output), AbCip.md, CLAUDE.md.
Claude-Session: https://claude.ai/code/session_01Ef2ozxS7QPanGT8uoATbTe
Joseph Doherty