Referring to FIG. 5C, USB peripheral device 510 is coupled to receptacle 524a and USB host device 512′ to receptacle 524b. In one embodiment, USB host device 512′ may be an Apple product. Operation of USB system 580 may be similar to USB system 550 in FIG. 5B. In one embodiment, head unit 502 may send USB command signals to control circuit 506, which in turn may send control signals to first, second, and third signal repeaters 518, 516, and 514. Host signal path may be established between head unit 502 and USB peripheral device 510 through USB host port 526, USB hub 504, downstream port 520a, and first signal repeater 518, in which head unit 502 acts as a USB host. Concurrently and individually, peripheral signal path may be established between USB peripheral/OTG port 522 of head unit 502 and the Apple product 512′ after the CarPlay? mode is enabled through third signal repeater 514, and second signal repeater 516, in which the Apple product 512′ acts as a USB host and head unit 502 a USB peripheral. In one embodiment, there may be two USB hosts, head unit 502 (to host signal path and USB device 510) and the Apple product or USB host device 512′ (to peripheral signal path and head unit 502) in USB system 580.

In one alternative embodiment (not shown), when head unit 502 detects both receptacles 524a and 524b are coupled to Apple products or USB host devices, head unit 502 may select one of the USB host devices for CarPlay? mode operation, or may offer the user an opportunity to select which USB host device is to be operated in CarPlay? mode.