Share the Alamo gateway request budget

[onehouse] / doc / m31.rst

diff --git a/doc/m31.rst b/doc/m31.rst
index 69c1703f637f9d5f8be85027710d8e29b2400ef2..b0305e346d0131f7b048553666a695c89d404b16 100644 (file)
--- a/doc/m31.rst
+++ b/doc/m31.rst
@@ -33,10 +33,10 @@ load. The conservative sixteen-module limit includes the host.
 ***************
 
 ``NewTCPClient`` supplies a caller-owned, serialized connection through
-``Client``. Connect selects the configured unit and has a two-second
-timeout. A request has a one-second write deadline and a two-second
-response deadline, both measured from its start. Caller deadlines and
-cancellation can stop it earlier. Each response must match the
+``Client``. Connect selects the configured unit and has a one-second
+timeout. Each write has a one-second deadline. Each response has a
+two-second deadline measured after the request write. Caller deadlines
+and cancellation can stop it earlier. Each response must match the
 transaction, unit, function, length, and write acknowledgement.
 Supported functions are 01, 02, 03, 05, 15, and 16. No external Modbus
 package is required.
@@ -122,3 +122,9 @@ cancellation, duplicate replay, and failed feedback or result sends.
 They do not verify electrical simultaneity, contact timing, hardware
 interlocks, or physical pulse width. Local motor protection remains
 necessary when network commands control moving equipment.
+
+A caller cancellation interrupts blocked transport work through its
+deadline. A timeout caused only by that interruption is a context stop
+for the runner. A joined independent transport or cleanup failure stays
+a failure. Operation timeouts while the worker context is active remain
+device failures and enter reconnect recovery.