Patent ID: 7457974

Claim:
A method for selectively providing a clock signal to a device, the method comprising: coupling a slave device to a master device, wherein the slave device is a PCI card that controls the motherboard, and wherein either the master clock signal or the internal clock signal controls a timing of a PCI bus in the PCI card, wherein the master device is a motherboard that comprises a processing unit, a memory, and a Peripheral Component Interconnect (PCI) controller; powering on the slave device while the master device is powered off, wherein the powered on slave device generates an internal clock signal; in response to the master device being powered on, disabling the internal clock signal and sending the slave device a master clock signal from the master device; asserting, by a PCI controller on the motherboard, a reset signal when the motherboard assumes a master role over the PCI card; asserting, by a power supply on the motherboard, a “power on” signal when the motherboard is powered on; outputting, from a first Boolean logic, a first logical signal that describes if the reset signal and the power on signal are asserted; and outputting, from a second Boolean logic that is coupled to the first Boolean logic, a second logical signal that is based on the first logical signal.