US Patent 7447827 Multi-port bridge device

A bridge device electrically connected to a first AGP bus, a second AGP bus, and a PCI bus is provided. The bridge device has a first bridge, a second bridge, and a controller. The first bridge is electrically connected between the first AGP bus and the second AGP bus. The second bridge is electrically connected between the first AGP bus and the PCI bus. The controller is electrically connected to the first AGP bus, the first bridge, and the second bridge. As a configuration cycle corresponding to the first bridge being transmitted through the first AGP bus to the controller, the controller responds a preset message implying that the first bridge does not exist.