FC09 — Event Groups and multi-event synchronization
This deterministic card implements two distinct protocols on one genuine FreeRTOS EventGroup:
- a priority-3 coordinator waits for ALL independent readiness bits;
- coordinator, worker A and worker B cross a three-party
xEventGroupSync()barrier.
READY (0x01, 0x02) and SYNC (0x10, 0x20, 0x40) masks are disjoint.
The partial mask cannot release either protocol. Every participant receives a
return value containing SYNC_ALL, while the group value becomes zero after
the barrier's automatic clear.
make task1 host-test check-abi sim check-determinism
The test links upstream FreeRTOS V11.3.0 event_groups.c, uses finite
timeouts, records eleven commit-last events and prints a stable digest from
three clean Hazard3 processes.
Interactive views: A2 structure, A4 participant topology, A5 execution flow, A6 mask/state machine, A7 runtime evidence and A8 synchronization patterns.
Source basis: FreeRTOS Kernel Book, Chapter 9.