| 摘要 |
A system for controlling one or more handheld electronic devices (HEDs) each attached to the system by a respective universal serial bus (USB) output port 5. The system comprising a microcontroller 2, a bias circuit 3 and a switch 1. Wherein the microcontroller controls the bias circuit and the switch to selectively cause some or all of the attached HEDs to switch between a high-current charging state, a data-transmission state and a simulated disconnected state without the need for physically disconnecting HEDs from the system or resetting a device connected to the input port 4. Bias resistors may be used to cause HEDs to switch to a high-current charging state. The voltage across the USB output ports may be reduced to zero volts and the VBUS voltage removed to simulate disconnection of the HEDs. |
