Computer system with unattended operation power-saving suspend mode

• US 5,926,404 A
• Filed: 11/12/1997
• Issued: 07/20/1999
• Est. Priority Date: 05/23/1995
• Status: Expired due to Term

• Current Assignee: Dell USA LP (Dell Technologies Inc.)
• Original Assignee: Dell USA LP (Dell Technologies Inc.)
• Inventors: Zeller, Charles P., Walker, James L., Witte, Kendall C.
• Primary Examiner(s): MOISE, EMMANUEL LIONEL
• Application Number:
  US08/968,383
• Time in Patent Office: 615 Days
• Field of Search: 364/707, 364/708.1, 364/492, 395/750, 395/375
• US Class Current: 713/321
• CPC Class Codes: G06F 1/3228 Monitoring task completion, e.g. by use of idle timers, stop commands or wait commands

Abstract

A portable computer is provided with enhanced power management capabilities. The portable computer includes a power management system which makes a determination as to whether the computer is "user attended" or "user unattended" based upon the position of the display screen in one embodiment. If the display screen is open, then the computer is regarded as being "user attended". In this case, a first timeout delay of I/O inactivity is applied before the computer is permitted to enter a power saving suspend mode. However, if the display screen is closed, then the computer is regarded as being "user unattended". Is this situation, a second timeout delay of I/O inactivity is applied before the computer is allowed to enter the power saving suspend mode. The second timeout delay is generally significantly shorter than the first timeout delay. This technique is found to significantly increase the reliability of I/O activities such as external communications with the computer when the computer is "user unattended".

Claims

1. A portable computer system comprising:

a processor;

a main memory coupled to the processor;

a plurality of power consuming devices coupled to the processor; and

power managing means, coupled to the processor, for determining if the computer system is presently user attended or user unattended, the power managing means powering down the computer system to a suspend state if the computer system is determined to be attended and a first the period of no input/output activity has expired, the power managing means powering down the computer system to the suspend state if the computer system is determined to be unattended and a second time period of no input/output activity has expired, the second time period being a non-zero time period.

2. The portable computer system of claim 1 further comprising first selecting means, coupled to the power managing means, for selecting the first time period.

3. The portable computer system of claim 1 further comprising second selecting means, coupled to the power managing means, for selecting the second time period.

4. The portable computer system of claim 1 wherein the second time period is fixed.

5. The portable computer system of claim 1 wherein said power managing means includes resume operation means for causing the computer system to change from the suspend state to an operational state when input/output activity occurs.

6. The portable computer system of claim 1 wherein one of the plurality of power consuming devices is an integral display screen which is movable from an open position to a closed position.

7. The portable computer system of claim 6 further comprising a display screen opened/closed indicator, the power managing means being coupled to the indicator to determine that the computer system is user attended when the indicator indicates that the display screen is in the open position and to determine that the computer system is user unattended when the indicator indicates that display screen is in the closed position.

8. The portable computer system of claim 1 wherein the first time period is greater than the second time period.

9. A portable computer system comprising:

a processor;

a system bus coupled to the processor;

a main memory coupled to the system bus;

a portable power source situated in the portable computer system to provide power thereto;

an integral panel display coupled to the system bus to permit the processor to display output to the user, the panel display being movable between an open position and a closed position; and

power managing means, coupled to the portable power source and the processor, for determining if the integral panel display is in the open position or the closed position, the power managing means powering down the computer system to a suspend state if the integral panel display is determined to be in the open position and a first time period of no input/output activity has expired, the power managing means powering down the computer system to the suspend state if the integral panel display is determined to be in the closed position and a second time period of no input/output activity has expired, the second time period being a non-zero time period.

10. The portable computer system of claim 9 further comprising a plurality of power consuming devices coupled to the power managing means.

11. The portable computer system of claim 9 wherein the portable power source comprises an electrical battery.

12. The portable computer system of claim 9 wherein the first time period is greater than the second time period.

13. The portable computer system of claim 9 further comprising first selecting means, coupled to the power managing means, for selecting the first time period.

14. The portable computer system of claim 9 further comprising second selecting means, coupled to the power managing means, for selecting the second time period.

15. The portable computer system of claim 9 wherein the second time period is fixed.

16. The portable computer system of claim 9 wherein said power managing means includes resume operation means for causing the computer system to change from the suspend state to an operational state when input/output activity occurs.

17. The portable computer system of claim 9 further comprising a display port for coupling the computer system to an external display.

18. The portable computer system of claim 17 wherein the power managing means includes external display testing means for determining if an external display is coupled to the display port.

19. The portable computer system of claim 18 wherein the power managing means powers down the computer system to the suspend state if the external display is determined to be coupled to the display port and the first time period of no input/output activity has expired.

20. A portable computer system comprising:

a plurality of power consuming devices; and

a power management circuit coupled to control the transfer of power to at least one of the power consuming devices, the power management circuit determine if the computer system is user unattended when the portable computer system is on, the power management circuit causing less power to be transferred to at least one of the power consuming devices after a first user-programmable time period of no input/output activity if the computer system is determined to be us attended, the power management circuit causing less power to be transferred to at least one of the power consuming vices after a second user-programmable time period of no input/output activity if the computer system is determined to be user unattended.

21. The portable computer system of claim 20 wherein the plurality of portable consuming devices comprises:

a processing unit;

a memory coupled to the processing unit; and

a display coupled to the processing unit.

22. A method of conserving power in a portable computer system, the portable computer system including power consuming devices which are coupled to a portable power supply, the method comprising the steps of:

determining if the portable computer system is presently user attended or us unattended;

powering down at least one of the power consuming devices to a suspend state if in the determining step the computer system is determined to be user attended and a first time period of no input/output activity has expired; and

powering down at least one of the power consuming devices to a state if in the determining step the computer system is determined to be user unattended and a second time period of no input/output activity has expired, the second time period being a non-zero time period.

23. The method of claim 22 wherein the first time period is greater than the second time period.

24. The method of claim 22 further comprising the step of selecting the first time period.

25. The method of claim 22 further comprising the step of selecting the second time period.

26. The method of claim 22 wherein the second time period is fixed.

27. The method of claim 22 further comprising the step of determining if input/output activity has commenced in the computer system.

28. The method of claim 27 further comprising the step of resuming fully powered up operation of the at least one of the power consuming devices when input/output activity commences in the computer system.

29. The method of claim 22 wherein the portable computer system includes an integral display screen which is movable between an open position and a closed position, the step of determining if the portable computer system is presently user attended or user unattended including testing the position of the integral display screen to find if the integral display screen is open or closed to indicate whether the portable computer system is user attended or user unattended, respectively.

30. The method of claim 22 wherein the portable computer includes a display port for coupling to an optional external display, the step of determining if the portable computer system is presently user attended or user unattended including testing to find if an external display is coupled to the display port, the presence of an optional external display indicating that the computer system is user attended, the absence of an optional display indicating that the computer system is user unattended.

31. A method of conserving power in a portable computer system, the portable computer system including an integral panel display which is movable from an open position to a closed position, the portable computer system including a portable power supply, the method comprising the steps of:

determining if the integral panel display is in the open position or the closed position;

powering down the portable computer system to a suspend state if in the determining step the integral panel display is in the open position and a first time period of no input/output activity has expired; and

powering down the portable computer system to the suspend state if in the determining step the integral panel display is in the closed position and a second time period of no input/output activity has expired, the second time period being a non-zero time period.

32. The method of claim 31 wherein the first time period is greater than the second time period.

33. The method of claim 31 further comprising the step of selecting the first time period.

34. The method of claim 31 further comprising the step of selecting the second time period.

35. The method of claim 31 wherein the second time period is fixed.

36. The method of claim 31 further comprising the step of determining if input/output activity has commenced in the computer system.

37. The method of claim 36 further comprising the step of resuming fully powered up operation of the computer system when input/output activity commences in the computer system.

38. The method of claim 31 wherein the portable computer includes a display port for coupling to an optional external display, the method further comprising the step of testing to find if an external display is coupled to the display port.

39. The method of claim 38 further comprising the step of powering down the portable computer system to a suspend state after a first time period has expired and both the integral panel display is in the closed position and an external display is coupled to the display port.

40. A method of cons power in a portable computer system, the method comprising:

initializing a time-out period to an attended time-out time upon system initialization;

determining if the portable computer system is attended or unattended;

determining if an I/O event has occurred;

setting the time-out period to the attended time-out time upon an I/O event if the portable computer system is attended;

setting the time-out period to an unattended time-out time upon an I/O event if the portable computer system is unattended, the unattended time-out time being a non-zero time;

determining if the time-out period has expired;

powering down the portable computer system to a suspend state if the time-out period has expired; and

powering up the portable computer system if an I/O event has occurred and the portable computer system is in the suspend state.

41. A method of conserving power in a portable computer system as recited in claim 40, the portable computer system including an integral display which is movable from an open position to a closed position, wherein the determining if the portable computer system is attended or unattended comprises:

determining that the portable computer system is attended if the integral display is in the open position.

42. A method of conserving power in a portable computer system as recited in claim 41, wherein the determining if the portable computer system is attended or unattended further comprises:

determining that the portable computer system is attended if the integral display is in the closed position and if an external display is coupled to the portable computer system; and

determining that the portable computer system is unattended if the integral display is in the closed position and if an external display is not coupled to the portable computer system.

43. A method of conserving power in a portable computer system as recited in claim 40, wherein the determining if the portable computer system is attended or unattended comprises detecting the presence of a user by a wave energy detection device for detecting at least one of the group consisting of electromagnetic waves and acoustic waves.

44. A method of conserving power in a portable computer system as recited in claim 40, wherein the determining if an I/O event has occurred comprises at least one of the group consisting of the following:

detecting a keystroke of a keyboard of the portable computer system;

detecting an alarm of a real time clock circuit of the portable computer system; and

detecting an incoming call on a modem of the portable computer system.

45. A method of conserving power in a portable computer system as recited in claim 44, wherein the determining if the portable computer system is attended or unattended comprises at least one of the following:

determining that the portable computer system is attended if a keystroke of a keyboard of the portable computer system is detected;

determining that the portable computer system is unattended if an alarm of a real time clock circuit of the portable computer system is detected; and

determining that the portable computer system is unattended if an incoming call on a modem of the portable computer system is received.

46. A method of conserving power in a portable computer system as recited in claim 40, wherein the powering down the portable computer system to a suspend state if the time-out period has expired comprises:

saving the state of the portable computer system; and

lowering power usage of the portable computer system.

47. A method of conserving power in a portable computer system as recited in claim 46, wherein the powering up the portable computer system if a user or communications I/O event has occurred and the portable computer system is in the suspend state comprises:

increasing power usage of the portable computer system; and

restoring the portable computer system to the saved state.

48. A method of conserving power in a portable computer system as recited in claim 40, wherein the initializing the time-out period to an attended time-out time upon system initialization comprises one of the group consisting of:

initializing the time-out period to an attended time-out time when the system is turned on; and

initializing the time-out period to an attended time-out time after the system is reset.

49. A method of conserving power in a portable computer system as recited in claim 40, the method further comprising:

powering down the portable computer system to a suspend state responsive to a hot-key input.

50. An apparatus for conserving power in a portable computer system, the comprising:

a computer-readable storage medium; and

an initialization module stored on the computer-readable storage medium, the initialization module for initializing a time-out period to an attended time-out time upon system initialization;

a determination module stored on the computer-readable storage medium, the determination module for detecting the occurrence of I/O events and for determining the attended/unattended state of the portable computer system;

a timer setting module stored on the computer-readable storage medium, the timer setting module for setting the time-out period to the attended time-out time upon an I/O event if the portable computer system is attended and for setting the time-out period to an unattended time-out time upon an I/O event if the portable computer system is unattended, the unattended time-out time being a non-zero time;

a time-out detection module stored on the computer-readable storage medium, the time-out detection module for determining if the time-out period has expired; and

a power management module stored on the computer-readable storage medium, the power management module for powering down the portable computer system to a suspend state if the time-out period has expired and for powering up the portable computer system if an I/O event has occurred and the portable computer system is in the suspend state.

51. An apparatus as recited in claim 50, the apparatus further comprising a hot-key module stored on the computer-readable storage medium, the hot-key module for causing the computer system to enter the suspend state without waiting for the time-out period to expire responsive to detecting a hot-key input.

52. An apparatus as recited in claim 50 wherein the computer-readable storage medium is a non-volatile memory;

and the modules are firmware modules stored within a basic input/output system.

53. An apparatus as recited in claim 50 wherein the apparatus is a computer system, the apparatus further comprising a portable power source and a plurality of power consuming devices coupled to the portable power source, the modules stored on the computer-readable storage medium managing the power received by the power consuming devices from the portable power source when the computer system is on.