VirtualLink is a proposed USB-C alternate mode that allows the power, video, and data required to power virtual reality headsets to be delivered over a single USB-C cable and connector instead of set of three different cables as it was in older headsets. The standard is supported by Nvidia, AMD, HTC Vive, Oculus VR, Valve, and Microsoft. The VirtualLink Consortium is chaired by Rambod Jacoby representing NVIDIA.
- 4x DisplayPort balanced pair data path
- DisplayPort HPD (hot-plug detection pin) as a single wire.
- DisplayPort AUX signal as a balanced pair
- USB 3.1 signals
- A USB TX balanced pair for USB 3.0 data
- A USB RX balanced pair for USB 3.0 data
- I2C wire to control the USB Billboard interface, in case the cable is plugged into an unsupported interface.
- VBUS carrying power to HMD visor
- GND ground
Unlike most alt-mode; this will also remap A7, A6, B6, B7 to carry USB 3.0 signals, instead of the usual passive USB 2.0 signal. This means that one will not be able to extend the cable using a standard USB-C 3.0 cable, which has these pins mapped only for unshielded USB 2.0 signals. Also this will require the VirtualLink port to also detect the correct orientation of the USB-C plug to ensure that the USB 3.0 TX and RX lanes are correctly connected.
Testing the VirtualLink port showed a USB-C to 4x USB-A box worked fine. Other USB-C boxes like a camera card reader worked fine. The VirtualLink connection seems to be a carbon copy of the Apple USB-C seem on their MacBook machines. Evidently this more marketing than tangible hardware.