Per-port event queues

The TCU keeps one event FIFO for each configured local output port. Events carry the label of their time point, so one label can select simultaneous events from several ports.

Connections

• Input: resolved OperationEvent values inserted during atomic time point enqueue.

• Output: the matching events for a due label and occupancy for enqueue checks.

• Owner: TcuCycleModel::events_; these queues share the TCU edge with the timer and timing queue.

Matching a label

When a time point is due, the TCU collects the leading events with that label from each port queue. Their IDs must match the time point’s manifest exactly. Other ports remain idle; later labels stay queued.

After condition evaluation and device validation, all events for the label leave their queues together. A false condition produces ConditionCancelled instead of sending that event to the device.

event_capacity limits queued entries per output port. firing_width limits events per output port at one time point. See enqueue checks.

Objects and state

Object or member	Representation	Role
events_	vector<deque<OperationEvent>>	One FIFO per configured local output port.
OperationEvent::label and id	time point and member identities	Matches queued members to the timing-head manifest.
TimingConfig::event_capacity and firing_width	bounds	Storage and same-point output limits per port.

C++ API.

Reset and errors

A missing or extra member, duplicate ID, stale epoch or orphan event preceding the timing head faults the complete time point before output. Reset empties every port queue. No partial dequeue is committed after failed validation.

Implementation and tests

Source: tcu.cpp and tcu.hpp.

CTest: control.admission, control.atomic.

The tests check simultaneous output on several ports and capacity before triggering. Failed validation must leave every event in the time point queued.