Vehicle ECU Bus Synchronization Using Count-Based Start Timing

A gateway ECU is introduced as an intermediary device between the central ECU and zone ECUs on different buses. The gateway receives control signals from the central ECU, determines whether they require synchronized execution across multiple buses, and if so, transmits the same control signal to multiple subordinate ECUs on different buses simultaneously. This intermediary mechanism ensures that zone ECUs on different buses execute operations at the same timing, resolving the transmission timing deviation problem while maintaining expanded connection coverage.

The communication system is segmented into multiple independent buses (first bus, second bus, etc.) that can operate in parallel. Instead of connecting all zone ECUs to a single overloaded bus, the system divides the network into multiple segments, each handling a subset of zone ECUs. This segmentation reduces the load on each individual bus, minimizing transmission delays while maintaining overall system connectivity. The gateway ECU coordinates between these segmented buses to ensure synchronized operation.

Count signals are transmitted periodically at fixed intervals with the highest transmission priority, creating a regular timing reference framework. Each count signal contains a monotonically increasing count value that serves as a synchronized timestamp. Subordinate ECUs use these periodic count signals to align their operation timing. The periodic nature of this high-priority signal transmission provides a simple yet effective mechanism for achieving precise timing synchronization without requiring complex dynamic priority management, as the priority structure is static and predictable.