Universal quick port-switching method and associated apparatus

1. A universal quick port-switching detecting apparatus, comprising:

a plurality of resistors, for receiving a plurality of ground signals from a plurality of video receiving ports of a video display device, respectively, wherein the ground signals are supplied through the plurality of video receiving ports, said receiving ports employing transition minimized differential signaling (TMDS) signals;

a voltage-dividing detecting circuit, coupled to the resistors, for generating a single predictable divided voltage; and

an analog-to-digital converter (ADC), coupled to the voltage-dividing detecting circuit, for generating a single digital output according to the single predictable divided voltage;

wherein the universal quick port-switching detecting apparatus simultaneously identifies, according to the single digital output, which one or ones of the video receiving ports are active while respective engines associated with the video receiving ports are inactive, and

wherein the respective engines are disposed in the video display device.

2. The apparatus as claimed in claim 1 , wherein the ADC is a successive approximation register analog-to-digital converter (SAR ADC).

3. The apparatus as claimed in claim 1 , wherein the voltage-dividing detecting circuit comprises a pull-up resistor coupled to a voltage supply.

4. The apparatus as claimed in claim 1 , wherein each of the resistors has a different resistance value.

5. The apparatus as claimed in claim 1 , wherein the receiving ports comprise a Video Graphic Array (VGA) port, a High-Definition Multimedia Interface (HDMI) port, a Digital Visual Interface (DVI) port, or a Display Port (DP) port.

6. The apparatus as claimed in claim 1 , wherein the resistors are precision resistors.

7. The apparatus as claimed in claim 2 , wherein the SAR ADC is provided in an integrated display controller.

8. The apparatus as claimed in claim 3 , wherein the resistors are coupled to the pull-up resistor.

9. A universal quick port-switching method, comprising steps of:

receiving a plurality of ground signals from a plurality of video receiving ports that are connected to respective video processing engines disposed in a video display device, respectively, wherein the ground signals are supplied through the plurality of video receiving ports, said receiving ports employing transition minimized differential signaling (TMDS) signals;

detecting a single predictable voltage generated using a plurality of resistors respectively connected between ground terminals of the video receiving ports and a common voltage source; and

determining, simultaneously and while the video processing engines are inactive, which one or ones of the receiving ports are active according to the single predictable voltage.

10. The method as claimed in claim 9 , wherein the receiving ports comprise a VGA port, an HDMI port, a DVI port, or a DP port.

11. The method as claimed in claim 9 , further comprising a step of performing analog-to-digital conversion on the predictable voltage using a SAR ADC to generate a digital output.

12. The method of claim 9 , wherein respective ones of the plurality of resistors have different values.

13. The method of claim 9 , wherein the predictable voltage results from two or more of the plurality of resistors being in parallel with one another.

14. The apparatus of claim 1 , wherein the predictable voltage results from two or more of the plurality of resistors being in parallel with one another.