Patent ID: 8806086

Claim:
A serial port connection circuit for selectively connecting either a baseboard management controller (BMC) or an input/output (I/O) chip to a serial port, the serial port connection circuit comprising: a first data transmission unit connected to the BMC; a second data transmission unit connected to the I/O chip; a third data transmission unit connected to the first data transmission unit, the second data transmission unit, and the serial port; and a fourth data transmission unit connected to the BMC, the I/O chip, and the serial port; wherein the first, second, third, and fourth data transmission units are all multiple selectors, and the serial port is selectively connected to either the BMC or the I/O chip by the first, second, third, and fourth data transmission units; and wherein the serial port is connected to the BMC via the first data transmission unit and the third data transmission unit connected in series and further via the fourth transmission unit, and is connected to the I/O chip via the second data transmission unit and the third data transmission unit connected in series and further via the fourth transmission unit.