Controlling power states of a computer

• US 6,125,449 A
• Filed: 04/03/1998
• Issued: 09/26/2000
• Est. Priority Date: 06/30/1997
• Status: Expired due to Fees

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Compaq Computer Corporation (HP Inc.)
• Inventors: D'Souza, Henry M., Kunkel, Larry W., Ali, Valiuddin, Bayramoglu, Gokalp, Taylor, Mark E.
• Primary Examiner(s): Ray, Gopal C.
• Application Number:
  US09/054,617
• Time in Patent Office: 907 Days
• Field of Search: 713/300, 713/324, 713/340, 713/321, 713/323, 713/310, 365/228, 361/679, 361/115, 327/198, 345/212, 307/66, 710/62, 710/63, 710/129, 710/260
• US Class Current: 713/310
• CPC Class Codes: G06F 1/26 Power supply means, e.g. regulation thereof for memories G11C

Abstract

Method and apparatus of controlling a power state of a computer, the computer being connected to a monitor having a power control button. The computer is connected to the monitor over a video cable, and activation of the power control button is communicated to the computer over a wire in the video cable. In response to the activation signal, a system management interrupt is generated to invoke an SMI handler to change the power state of the computer. The power states of the computer include an ON state, an intermediate power state (such as Sleep state), and a suspend state (such as Soft-Off state).

Claims

1. A method of controlling a power state of a computer, the computer being connected by a VGA cable to a monitor having a power control button, the method comprising:

receiving an activation signal over a dedicated wire in the VGA cable in response to actuation of the monitor power control button;

generating a system management interrupt in response to receipt of the activation signal; and

invoking a system management interrupt handler to change the power state of the computer, wherein the computer includes an ON state, an intermediate power state, and a suspend state.

2. A computer system, comprising:

a monitor having a power control button;

a power management controller coupled to the monitor, the power management controller being configured to change the power state of the computer system in response to actuation of the monitor power control button;

wherein the power management controller is coupled to the monitor over a video cable; and

wherein actuation of the monitor power control button is indicated by a signal transmitted over a dedicated wire of the video cable.

3. The computer system of claim 2, wherein the power management controller includes a bus device.

4. The computer system of claim 3, wherein the bus device includes a PCI-ISA bridge-chip.

5. The computer system of claim 4, wherein the bus device includes a PIIX4 PCI-ISA bridge chip.

6. The computer system of claim 2, wherein the power management controller includes a system management interrupt handler.

7. The computer system of claim 2, wherein the monitor includes a microcontroller configured to enable transmission of the actuation of the monitor power control button over the video cable.

8. The computer system of claim 7, further comprising:

a serial bus cable coupling the monitor and the power management controller, and

wherein the microcontroller is further configured to enable transmission of the actuation of the monitor power control button over either the video cable or the serial bus cable.

9. The computer system of claim 8, wherein the serial bus cable includes a Universal Serial Bus cable.

10. The computer system of claim 2, wherein the video cable includes a VGA cable.

11. The computer system of claim 2, wherein the power control button includes a sleep button.

12. The computer system of claim 2, wherein the computer includes at least two of the following states:

a suspend state, an intermediate power state, and an ON state.

13. The computer system of claim 12, wherein the suspend state includes a Soft-Off state.

14. The computer system of claim 2, wherein the power management controller is configured to determine the type of monitor, the power management controller enabling the control of the power state of the computer system only when the monitor is determined to be a power control monitor.

15. The computer system of claim 14, wherein the power management controller includes a BIOS routine.

16. The method of claim 2, wherein said video cable is a VGA video cable.

17. The method of claim 16, wherein said dedicated wire is wire 4 of VGA video cable.

18. A power management device for controlling a power state of a computer, the computer being connected to a monitor having a power control button, the power management controller comprising:

a detector coupled to the monitor to detect actuation of the power control button;

a controller configured to change the power state of the computer in response to actuation of the monitor power control button;

wherein the computer is coupled to the monitor over a video cable; and

wherein the detector receives an activation signal representing actuation of the monitor power control button over a dedicated wire of the video cable.

19. The power management device of claim 18, wherein the computer includes at least two of the following states:

a suspend state, an intermediate power state, and an ON state.

20. The power management device of claim 19, wherein the suspend state includes a Soft-Off state.

21. The method of claim 18, wherein said video cable is a VGA video cable.

22. The method of claim 21, wherein said dedicated wire is wire 4 of VGA video cable.

23. A system, comprising:

a monitor having a sleep button;

a video cable connected to the monitor, wherein the sleep button is actuated by communication over a dedicated line in the video cable; and

a computer connected to the video cable, the computer having a power management controller configured to change the power state of the computer in response to the sleep button being actuated by communication over the dedicated line in the video cable.

24. The method of claim 23, wherein said video cable is a VGA video cable.

25. The method of claim 24, wherein said dedicated wire is wire 4 of VGA video cable.

26. A computer system, comprising:

a monitor having a sleep button and a microcontroller, the microcontroller being connected to receive actuation of the sleep button;

a dedicated video cable line connected to the microcontroller, actuation of the sleep button being communicated over the dedicated video cable line;

a power management controller coupled to the dedicated video cable line, the power management controller being configured to transition the computer system to one of an ON state, Sleep state, and Soft-Off state in response to actuation of the sleep button; and

a mass storage device accessible by the power management controller.

27. A computer system, comprising:

a monitor;

a power control switch located on the monitor; and

a power management controller connected to the monitor to receive actuation of the power control switch, the power management controller being capable of placing the computer system into one of a sleep state and a suspend state.

28. The computer system of claim 27, wherein the power management controller places the computer system into the suspend state if the power control switch is actuated continuously for greater than a predetermined time period.

29. The computer system of claim 28, wherein the power management controller places the computer system into the sleep state if the power control switch is actuated for less than a predetermined time period.

30. The computer system of claim 27, wherein the suspend state includes a Soft-Off state.

31. The computer system of claim 27, wherein the power management controller includes a system management interrupt handler.

32. The computer system of claim 31, wherein the system management interrupt handler is configured to place the computer system into the Sleep state if the power control switch is actuated for less than a predetermined time period and into the suspend state if the power control switch is actuated for greater than the predetermined time period.

33. The computer system of claim 27, wherein the power control switch includes a Bezel power button.

34. A computer system, comprising:

a monitor;

a power control button located on the monitor;

a power controller that transitions the computer system to a low power state and sets a flag in non-volatile memory in response to a predefined event;

a routine that reads the state of the flag when the computer system is restarting from a power off condition to determine whether to transition the computer system in the low power state; and

wherein the predefined event includes actuation of the power control button.

35. The computer system of claim 34, wherein the predefined event includes actuation of the power button for more than a predetermined period of time.

36. The computer system of claim 35, wherein the power controller includes a power management component that is responsive to actuation of the power button for a predetermined period of time.

37. The computer system of claim 35, further comprising:

a timer that is started in response to actuation of the power button.

38. The computer system of claim 34, wherein the power controller includes an SMI handler invoked in response to the predefined event, the SMI handler setting the flag.

39. The computer system of claim 34, wherein the predetermined power state includes a Soft-Off state.

40. A method of controlling a power state of a computer, the computer being connected to a monitor over a video cable including wires, the monitor having a power control button, the method comprising:

receiving an activation signal representing actuation of the monitor power control button over a dedicated wire of the video cable; and

changing the power state of the computer in response to actuation of the monitor power control button.

41. The method of claim 40, wherein the power control button includes a sleep button.

42. The method of claim 40, wherein the computer includes a suspend state and an ON state.

43. The method of claim 42, wherein the suspend state includes a Soft-Off state.

44. The method of claim 40, wherein the computer includes an intermediate power state and an ON state.

45. The method of claim 44, wherein the intermediate state includes one of a Sleep state and a powered on suspend state.

46. The method of claim 40, wherein the computer includes a suspend state, an intermediate power state, and an ON state.

47. The method of claim 40, wherein said video cable is a VGA video cable.

48. The method of claim 47, wherein said dedicated wire is wire 4 of VGA video cable.