Power management system for a computer

A power-managed computer system with telephony capabilities comprising:

• a central processing unit having a normal power mode and a reduced power mode, said central processing unit being a contributor to general system activity;
• at least one peripheral coupled to said central processing unit and contributing to said general system activity, said at least one peripheral having a normal power mode and a reduced power mode;
• a telephony interface for transmitting or receiving a telephonic signal, said telephony interface including a port for coupling said telephony interface to a telephone system network;
• a power management means for determining telephony interface activity and for monitoring said general system activity, said power management means being operative to put at least one of said central processing unit and said peripheral in a reduced power mode in the absence of both a predetermined level of telephony interface activity and a predetermined level of general system activity, and said power management means being operative to return said at least one of said central processing unit and said peripheral to its normal power mode when at least one of said telephony interface activity and said general system activity is greater than respective said predetermined levels of activity;
• telephone circuitry for allowing said computer system to function as a telephone and capable of transmitting or receiving a telephonic signal;
• telephone interface software for managing said telephone circuitry, said telephone interface software providing an off-hook identifier to indicate said telephony interface activity to said activity detection logic in said power management means such that said activity detection logic interprets said off-hook signal as activity within said computer and prevents said computer system from being placed in a reduced power mode;
• and
• an enablement register in said power management means capable of being arranged to disable said power management means from shutting down power to said computer.

A method for managing power in a computer system having general system activity and telephony interface activity, said method comprising the steps of:

• monitoring both general system activity and telephony interface activity of said computer system running in a normal power mode;
• determining a level of general system activity and a level of telephony interface activity by sampling an off-hook identifier;
• placing said computer system in a reduced power mode in the absence of both a predetermined level of telephony interface activity and a predetermined level of general system activity as determined by said monitoring, whereby said computer system is prevented from being placed in a reduced power mode when said telephony interface activity is greater than said predetermined level of telephony interface activity, wherein said computer system includes:
• telephone circuitry for allowing said computer system to function as a telephone and capable of transmitting or receiving a telephonic signal, and telephone interface software for managing said telephone circuitry, said telephone interface software providing said off-hook identifier, and
• a power management unit for shutting down power to said computer system after a predetermined amount of time;
• and
• setting an enablement register in said power management unit in order to disable said power management unit from shutting down power to said computer.

A method for preventing the shutting down of power within a computer system, said computer system having telephone circuitry for allowing said computer system to function as a telephone and capable of transmitting or receiving a telephonic signal, a power source providing power for said computer system and said telephone circuitry, and a power management unit for shutting down the power to said computer system after a predetermined amount of time, said power management unit including activity detection logic for detecting activity within said computer system, the method comprising the steps of:

• enabling said power management unit of said computer system such that if no activity is detected by said activity detection logic said power management unit will shut down power to said computer system;
• enabling said telephone circuitry such that said computer system functions as a telephone, said telephone circuitry being in an off-hook state when said computer system functions as a telephone;
• determining whether said telephone circuitry is in an off-hook state;
• and
• wherein when it is determined that said telephone circuitry is in an off-hook state, preventing said power management unit from shutting down power to said computer system, such that said power source still provides power to said computer system and said telephone circuitry while said telephone circuitry is in an off-hook state.

A power-managed computer system with telephony capabilities comprising:

• a bus system;
• a central processing unit coupled to said bus system, said central processing unit having a normal power mode and at least one power saving mode;
• a telephony interface coupled to said bus system for transmitting or receiving a telephonic signal, said telephony interface including a port for coupling said telephony interface to a telephone system network, said telephony interface includes a modem for transmitting or receiving said telephonic signal, such that said modem provides an off-hook signal that is arranged to indicate said telephony interface activity;
• and
• a power management unit coupled to said bus system and responsive to bus system activity and to telephony interface activity, said power management unit being operative to cause said central processing unit to be in said power saving mode when both said bus system activity and said telephony interface activity are less than a predetermined level of activity and said power management unit being operative to maintain said central processing unit in a power mode greater than said power saving mode when at least one of said bus system activity and said telephony interface activity is greater than said predetermined level of activity.

A power-managed computer system with telephony capabilities comprising:

• a bus system;
• a central processing unit coupled to said bus system, said central processing unit having a normal power mode and at least one power saving mode;
• a telephony interface coupled to said bus system for transmitting or receiving a telephonic signal, said telephony interface including a port for coupling said telephony interface to a telephone system network;
• a power management unit coupled to said bus system and responsive to bus system activity and to telephony interface activity, said power management unit being operative to cause said central processing unit to be in said power saving mode when both said bus system activity and said telephony interface activity are less than a predetermined level of activity and said power management unit being operative to maintain said central processing unit in a power mode greater than said power saving mode when at least one of said bus system activity and said telephony interface activity is greater than said predetermined level of activity;
• activity detection logic in said power management unit for detecting said bus system activity and said telephony interface activity within said computer system;
• and
• sensing logic for determining the status of said telephonic signal and for generating an off-hook signal arranged to indicate said telephony interface activity to said activity detection logic in said power management unit such that said activity detection logic interprets said off-hook signal as activity within said computer and prevents said computer system from being placed in a reduced power mode.