Method and apparatus of controlling an operational status of an electronic device

1. A method of controlling an operational status of an electronic device, wherein the electronic device receives data through HDMI port, wherein the HDMI port has a clock channel for receiving a clock signal and at least one data channel for receiving data including at least audio and video information, comprising:

generating a checking result by counting a number of transitions of the received data in the data channel when the clock signal is detected and the electronic device is in a power saving mode, comprising:

generating a counting number for each time period by counting the number of transitions within each the time period;

comparing the counting number with a predetermined value; and

generating the checking result according to the result of comparison; and

determining whether to wake up the electronic device from the power saving mode according to the checking result.

2. The method of claim 1 , wherein the step of determining whether to wake up the electronic device from the power saving mode comprises:

waking up the electronic device when the checking result indicates that the previous counting number is equal to the predetermined value and the last counting number is smaller than the predetermined value.

3. The method of claim 2 , wherein the previous counting number is the second to the last counting number.

4. The method of claim 1 , the predetermined value is integer times of eight.

5. The method of claim 1 , each the time period is integer times of a clock cycle of the clock signal.

6. An apparatus of controlling an operational status of an electronic device, wherein the electronic device receives data through HDMI port, wherein the HDMI port has a clock channel for receiving a clock signal and at least one data channel for receiving data including at least audio and video information, comprising:

a check unit, coupled to the clock channel and the at least one data channel, for generating a checking result by counting a number of transitions of the received data in the data channel when the clock signal is detected and the electronic device is in a power saving mode, wherein the check unit generates a counting number for each time period by counting the number of transitions within each the time period; compares the counting number with a predetermined value; and then generates the checking result according to the result of comparison; and

a control unit, coupled to the check unit, for determining whether to wake up the electronic device from the power saving mode according to the checking result.

7. The apparatus of claim 6 , wherein the control unit wakes up the electronic device when the checking result generated by the check unit indicates that the previous counting number is equal to the predetermined value and the last counting number is smaller than the predetermined value.

8. The apparatus of claim 7 , wherein the previous counting number is the second to the last counting number.

9. The apparatus of claim 6 , the predetermined value is integer times of eight.

10. The apparatus of claim 6 , each the time period for which the check unit generates the counting number is integer times of a clock cycle of the clock signal.