| 摘要 |
<p>A computer system (20) includes a first power rail (38) having a first voltage level, such as 5 volts, and a second power rail (40) having a second voltage level, such as 3.3 volts. A PCI connector (30) receives a first type PCI card (50) having I/O buffers operable at the first voltage level or receives a second type PCI card (60) having adaptable I/O buffers operable at the first voltage level or the second voltage level. The PCI connector includes voltage I/O pins for supplying power to the I/O buffers. Sensing circuitry provides a sense signal having a first state when the first type PCI card is inserted and having a second state when the second type PCI card is inserted. Switching circuitry is responsive to the sense signal at the first state to provide the first voltage level on the voltage I/O pins and is responsive to the sense signal at the second state to provide the second voltage level on the voltage I/O pins. <IMAGE></p> |
