The resulting Wiegand protocol digital code is then sent to a host controller to determine whether to electrically unlock the door.

Each host controller provides one or more USB ports.

The root hub is built into to the host controller.

Pipes are connections from the host controller to a logical entity on the device named an endpoint.

The computer hardware that contains the host controller and the root hub has an interface for the programmer.

As for the open host controller, Intel plans to make the device's specification fully available to everyone, at no charge, as soon as it's complete.

Other circuits are designed to communicate through a serial port with a host controller in order to set switches on or off.

Up to 127 devices, including hub devices if present, may be connected to a single host controller.

A pipe is a connection from the host controller to a logical entity, found on a device, and named an endpoint.

They assumed the rather significant financial burden of designing a fast, reliable host controller, and released its specification to the world under a royalty-free license.