Computing device with flexibly configurable expansion slots, and method of operation
View Patent ↗A computing device that allows for a flexible allocation of bandwidth among peripheral devices using a peripheral bus is disclosed. The computing device includes a peripheral bus and at least two slots. The computing device may be used with a single peripheral card or multiple peripheral cards. In a multi-card configuration the invention allows the bandwidth on the peripheral bus to be shared by all the cards. In a single-card configuration, the computing device allows available bandwidth on the peripheral bus to be used by a single card. The device is particularly useful with PCI express compliant expansion cards, such as graphics adapters.
1. A method of operating a computing device comprising a peripheral bus having at least 2n data lines; a first expansion slot for receiving peripheral cards comprising 2n data line interconnects, and operable in a first mode using n of said 2n data lines, and in a second mode using 2n of said 2n data lines, said first expansion slot comprising a first set of n connectors, interconnected with n of said 2n data lines; and a second set of n connectors; a second expansion slot for receiving peripheral cards comprising 2n data line interconnects, and operable in a first mode using n of said 2n data lines, and in a second mode using 2n of said 2n data lines, said second expansion slot comprising a first set of n connectors, interconnected with n further ones of said 2n data lines; and a second set of n connectors, wherein each of the second set of n connectors of the first expansion slot is interconnected with one of the second set of n connectors of said second expansion slot; said method comprising:
disconnecting said second set of n connectors of said first expansion slot from said second set of n connectors of said second expansion slot; and
initializing peripheral cards in said first and second expansion slots, to each operate in its first mode to use n of said 2n data lines.
2. A motherboard operable in first and second modes of operation, said motherboard comprising:
a bus interface, interconnected to a peripheral bus having at least 2n data lines;
a first expansion slot for receiving peripheral cards, said first expansion slot comprising a first set of n connectors, interconnected with n of said 2n data lines, and a second set of n connectors; a second expansion slot for receiving peripheral cards said second expansion slot comprising a first set of n connectors, interconnected with n of said 2n data lines, and a second set of n connectors;
a bus switch selectively connecting each of said second set of n connectors of said first expansion slot to a corresponding one of said second set of n connectors of said second expansion slot in said second mode, and disconnecting each of said second set of n connectors of said first expansion slot from a corresponding one of said second set of n connectors of said second expansion slot in said first mode, thereby allowing peripheral cards comprising 2n data line interconnects received in said first and second expansion slots to each train to use n of said 2n data lines in said first mode.
3. The motherboard of claim 2 , wherein said bus switch is connected between n connectors of said first expansion slot and n connectors of said second expansion slot.
4. The motherboard of claim 3 , further comprising a reset control circuit operable to, in said first mode, reset a peripheral card in said second expansion slot, after initialization of a peripheral card in said first expansion slot, to train each of said first and second peripheral cards to use n of said 2n data lines.