Onboard Apparatus Bus Switch for Stable USB Communication

The patent applies preliminary action by introducing a permission signal that is generated in advance before the control block's output signals are stable. This permission signal is used to control the bus switch, ensuring that the data terminal remains disconnected during the unstable period. The permission signal is cleared only after the control block's output becomes stable, allowing normal communication to commence. This preliminary control mechanism prevents communication errors without significantly delaying startup.

The patent applies dynamics by making the bus switch state dynamic rather than static. The bus switch transitions from a non-conduction state during startup to a conduction state once the permission signal is cleared, indicating that the control block's output has stabilized. This dynamic state change allows the system to adapt to different operational phases: protecting against communication errors during startup while enabling normal data transmission once stability is achieved, thus resolving the trade-off between reliability and productivity.