Low-power-consumption monitor standby system

A cathode ray tube monitor for a computer system and configured for power management in response to signals from a host computer system, said monitor comprising:

• detector means for detecting absence of at least one of HSYNC and VSYNC signals conveyed to said monitor by a host computer;
• and
• power level control means for shutting down power-using circuitry in said cathode ray tube monitor in response to absence of one of the HSYNC and VSYNC signals, said power-using circuitry not including said detector means, circuitry for carrying said signals from said host computer system to said detector means, and said power control means;
• said detector means including a control circuit capable of detecting different combinations of the SYNC signals being absent and said power level control means is configured to operate in three power modes in response to the different combinations of the SYNC signals being absent, a first mode having all circuits on, a second mode having all power circuits selectively operable by said power level control means off save a cathode heater remaining on, and a third mode having all power circuits selectively operable by said power level control means off.

A method for saving power for a video display monitor comprising steps of:

• detecting periods of inactivity at user input apparatus;
• providing power level signals to said video display monitor by interrupting VSYNC and HSYNC signals to said video display monitor in different combinations in response to a different periods of inactivity;
• sensing said power level signals at said video display monitor;
• shutting down power circuits in said video display monitor except a cathode heater in response to one of said power level signals;
• and
• shutting down all power circuits in said video display monitor in response to another of said power level signals.

In a general-purpose computer system having a CPU, a memory, input apparatus, a monitor, and a video adapter for providing color, VSYNC, and HSYNC signals to the monitor, a power management system for managing power usage by the monitor, comprising:

• a timer for detecting periods of inactivity of the input apparatus, the timer including control routines executed by the CPU;
• an interrupter circuit configured to interrupt at least one of the signals provided by the video adapter to the monitor in response to the detection of said periods of inactivity, the interrupter circuit including the CPU signalling the video adapter to disable one of the signals provided to the monitor;
• and
• a power manager circuit associated with the monitor configured to selectively power circuits in the monitor in response to interruption of one of the signals provided by the video adapter to the monitor,
• the power management system causing the CPU to disable the signals in different combinations in response to different periods of input activity.

In a general-purpose computer system having a CPU, a memory, input apparatus, a monitor, and a video adapter for providing color, VSYNC, and HSYNC signals to the monitor, a power management system for managing power usage by the monitor, comprising:

• a timer for detecting periods of inactivity of the input apparatus, the timer including an add-in time-out controller, the add-in time out controller including circuitry for detecting periods of inactivity of input apparatus,
• an interrupter circuit configured to interrupt at least one of the signals provided by the video adapter to the monitor in response to the detection of said periods of inactivity, the interrupter comprises more than one switch operable in more than one line carrying one of the signals provided by the video adapter to the monitor, and the time-out controller interrupts the signals provided by the video adapter to the monitor in different combinations in response to different periods of inactivity of the input apparatus;
• and
• a power manager circuit associated with the monitor configured to selectively power circuits in the monitor in response to interruption of one of the signals provided by the video adapter to the monitor.

In a general-purpose computer system having a CPU, a memory, input apparatus, a monitor, and a video adapter for providing color, VSYNC, and HSYNC signals to the monitor, a power management system for managing power usage by the monitor, comprising:

• a timer for detecting periods of inactivity of the input apparatus;
• an interrupter circuit configured to interrupt at least one of the signals provided by the video adapter to the monitor in response to the detection of said periods of inactivity;
• and
• a power manager circuit associated with the monitor configured to selectively power circuits in the monitor in response to interruption of one of the signals provided by the video adapter to the monitor, the power manager circuit including circuitry for monitoring the incoming signals provided by the video adapter, and for reducing power use by circuitry other than the power manager in response to interruption of one or both of the HSYNC and the VSYNC signals, the circuitry other than the power manager including a filament heater.

A general-purpose computer configured to signal a monitor to assume alternate power-using states, the general-purpose computer comprising:

• a CPU;
• a memory connected to the CPU for storing data and instruction routines;
• input apparatus coupled to the CPU for a user to provide input to the computer;
• a video adapter coupled to the CPU for providing signals for a display on a monitor, the signals including at least one color signal, and HSYNC, and VSYNC signals;
• a timer for detecting periods of inactivity of the input apparatus and to provide different control signals in response to different periods of inactivity;
• and
• an interrupter circuit for interrupting the signals provided by the video adapter for the monitor in different combinations in response to the different control signals.

A cathode ray tube monitor for receiving color, HSYNC, and VSYNC signals from a computer, comprising:

• a detector configured to detect absence of one of the signals received from the computer;
• and
• a power manager circuit configured to reduce power consumption by power-using circuitry in the monitor in response to the detection of the absence of one of the signals received from the computer;
• the power manager circuit providing power at different power levels, including full power, off, and at least one intermediate level.

A cathode ray tube monitor for receiving color, HSYNC, and VSYNC signals from a computer, comprising:

• a detector configured to detect absence of one of the signals received from the computer;
• and
• a power manager circuit configured to reduce power consumption by power-using circuitry in the monitor in response to the detection of the absence of one of the signals received from the computer;
• the cathode ray tube monitor being operable in a first power mode providing full power to all power-using circuitry in response to all signals present, a second power mode imposing power off to all power-using circuitry in the monitor other than the detector, the power manager, and a filament heater, and a third mode imposing power off to all power-using circuitry in the monitor other than the detector and the power manager.

A method for saving power in operation of a computer system sending color, HSYNC, and VSYNC signals to a monitor, comprising the steps of:

• sensing periods of inactivity of input apparatus of the computer system;
• interrupting one of the signals to the monitor in response to a period of inactivity of the input apparatus;
• detecting the absence of the signal at the monitor;
• and
• reducing power to a filament heater in the monitor in response to a first period of inactivity of the input apparatus, and suspending power to the filament heater in response to a second period of inactivity.

A method for saving power in operation of a computer system sending color, HSYNC, and VSYNC signals to a monitor, comprising the steps of:

• sensing periods of inactivity of input apparatus of the computer system;
• interrupting one of the signals to the monitor in response to a period of inactivity of the input apparatus;
• detecting the absence of the signal at the monitor;
• and
• reducing power to power-using circuitry in the monitor in response to the absence of the signal at the monitor;
• power being provided in three states to the power-using circuitry in the monitor, a first state providing full power to all of the power-using circuits in the monitor, a second state suspending power to power-using circuitry in the monitor except a filament heater, and a third state suspending power to power-using circuitry in the monitor including the filament heater.

In a computer configured to provide color, HSYNC, and VSYNC signals to a video monitor, a method for signalling the video monitor to assume an alternative power-using state, comprising the steps of:

• detecting a period of inactivity of input apparatus coupled to the computer;
• and
• interrupting one of the signals to the monitor in response to a period of inactivity as a command to the monitor to assume an alternative power-using state;
• the signals to the monitor being interrupted in a first combination in response to a first period of inactivity of the input apparatus, and in a second combination in response to a second period of inactivity, as commands to the monitor to assume alternative power-using states.