Abstract: A computer system having four states of power management: a normal operating state, a standby state, a suspend state, and an off state. A control unit controls transitions between the various states. The standby state is characterized by devices, such as a video controller and a hard drive, being placed into a low-power mode transparent to the operating system and the applications executing on the computer system. The suspend state is characterized by executing code being interrupted and the state of the computer system being saved to a file on the hard drive in such a manner that system power may be removed after the state of the computer system is saved to the hard drive. Later, after system power is restored, the state of the computer system is resumed by reading from the hard drive and loading it in such a manner that the operating system and application programs are not adversely affected.

Abstract: A computer system having a CPU, a non-volatile storage device, a power management processor having a volatile power management configuration, and a power supply in circuit communication. Responsive to the AC power to the power supply being interrupted, the CPU restores the volatile power management configuration to said power management processor. The power management configuration comprises a value corresponding to a wake alarm and whether the power management processor responds to external events.

Abstract: A computer system having a CPU, a switch, a power supply, and power supply control logic for controlling the state of the power supply via a control signal. The power supply control logic comprises circuitry to interface control of the power supply between the CPU and the user via the switch. The power supply control logic further comprises a fault circuit that detects a fault condition in the power supply and negates the control signal, thereby clearing the fault condition in the power supply.

Abstract: A method of saving and restoring the state of a CPU operating code in protected mode on a computer system. The save method makes use of BIOS operating in shadow RAM located in a region where linear addresses equal physical addresses while saving the state of the CPU. The registers that cannot be directly saved to memory are determined by searching the system memory for data structures that correspond to the particular register. The restore method uses dummy page tables that point to the shadowed BIOS to allow the CPU to reenter protected mode without generating a protection fault.

Abstract: A suspend/resume computer system having a CPU, a non-volatile storage device, volatile registers and memory data, a power management processor, a backup suspend timer and a power supply in circuit communication. The power management processor controls the regulation of power to the CPU by the power supply. The suspend/resume system is controlled by an operating system having power management control. The backup suspend timer executes independently of the power management portion of the operating system. The backup suspend timer causes the system to suspend if the power management portion of the operating system ceases functioning and the system should otherwise be suspended.

Abstract: A computer system having at least three states of power management: a normal operating state, a standby state, and a suspend state. The standby state is characterized by devices, such as a video controller and a hard drive, being placed into a low-power mode transparent to the operating system and the applications executing on the computer system. The suspend state is characterized by executing code being interrupted and the state of the computer system being saved to a file on the hard drive in such a manner that system power may be removed after the state of the computer system is saved to the hard drive. Later, after system power is restored, the state of the computer system is resumed by reading from the hard drive and loading it in such a manner that the operating system and application programs are not adversely affected.

Abstract: A computer system having four states of power management: a normal operating state, a standby state, a suspend state, and an off state. The standby state is characterized by devices, such as a video controller and a hard drive, being placed into a low-power mode transparent to the operating system and the applications executing on the computer system. The suspend state is characterized by executing code being interrupted and the state of the computer system being saved to a file on the hard drive in such a manner that system power may be removed after the state of the computer system is saved to the hard drive. Later, after system power is restored, the state of the computer system is resumed by reading from the hard drive and loading it in such a manner that the operating system and application programs are not adversely affected. The normal operating state and the off state correspond to the typical on and off states of more conventional computer systems.

Abstract: A computer system having a CPU, a power management processor, a switch, a modem, a timer, an override circuit, a glitch circuit, and a power supply in circuit communication. The power supply has several power supply states, which are controlled by the power management processor responsive to the CPU, the switch, the modem, the timer, the glitch circuit, the override circuit, and the power management processor itself.

Abstract: A computer system having a suspend/resume capability in addition to the normal operating state and the off state. Closure events of single momentary pushbutton switch control changes between the normal operating state, the suspend state, and the off state, depending on the value of a flag. If the flag is set in a certain state, closure events of the switch cause the computer system to change back and forth between the normal operating state and the off state. If the flag is set in a different state, closure events of the switch cause the computer system to change back and forth between the normal operating state and the suspend state. The switch also controls the video subsystem of the computer system such that pressing the switch blanks the video display terminal giving the user instantaneous feedback of the switch press.

Abstract: A desktop computer system having the capability to suspend and resume the state of the computer system. The suspended system state is saved to the system hard file such that system power may be removed, effectively allowing a system suspend requiring no power from the power supply.

Abstract: A computer system having a CPU, a non-volatile storage device, a power management processor having a volatile power management configuration, and a power supply in circuit communication. The power management processor controls the regulation of power to the CPU by the power supply. Prior to causing the power supply to cease providing regulated power to the CPU, the power management processor interrupts the CPU via a system management interrupt. Responsive to being interrupted via the system management interrupt, the CPU performs tasks associated with the power supply imminently ceasing to provide regulated power to the CPU. Such tasks include writing data to non-volatile memory and refreshing an alarm value in the power management processor. The CPU can extend the period of time before the power management processor causes the power supply to cease providing regulated power to the CPU while the CPU performs the necessary tasks.

Abstract: A method of saving and restoring the state of a CPU operating code in protected mode on a computer system. The save method makes use of BIOS operating in shadow RAM located in a region where linear addresses equal physical addresses while saving the state of the CPU. The registers that cannot be directly saved to memory are determined by searching the system memory for data structures that correspond to the particular register. The restore method uses dummy page tables that point to the shadowed BIOS to allow the CPU to reenter protected mode without generating a protection fault.

Abstract: This invention relates to updating a display unit associated with a remote computer system communicating with a host computer system. Information, which is currently being displayed on the display unit and information to be displayed thereon are compared to determine any differences which exist therebetween. If the differences exceed a predetermined value, a update command is generated and transmitted by the host computer system to the remote computer system along with the information to be displayed if facilitate the updating of the display unit. If the differences do not exceed the predetermined value, it is determined which of a plurality change categories should be used to transmit the differences to the remote system in the most efficient manner. An update command, which is associated with the selected one of the plurality of change categories, and data representing the differences are then enqueued for transmission to the remote system to facilitate the updating of the display unit.

Abstract: This invention relates to updating a display unit associated with a remote computer system communicating with a host computer system. Information, which is currently being displayed on the display unit and information to be displayed thereon are compared to determine any differences which exist therebetween. If the differences exceed a predetermined value, an update command is generated and transmitted by the host computer system to the remote computer system along with the information to be displayed if facilitate the updating of the display unit. If the differences do not exceed the predetermined value, it is determined which of a plurality change categories should be used to transmit the differences to the remote system in the most efficient manner. An update command, which is associated with the selected one of the plurality of change categories, and data representing the differences are then enqueued for transmission to the remote system to facilitate the updating of the display unit.

Abstract: This invention relates to assigning disk drives associated with both a host computer and a remote computer coupled together by a communication link using normal DOS driver letters. DOS initialization of the host computer is postponed until a remote session is established with the remote computer and the remote computer provides information regarding the disk drives associated therewith. Upon receiving the disk drive information from the remote computer, the host completes its initialization and assigns drive letters associated with diskette drives associated with the host computer to diskette drives associated with the remote computer. Thus, host diskette drives are logically replaced by remote diskette drives. Any hard disk drives associated with the remote computer are assigned the next available drive letter on the host computer.

Abstract: A method and apparatus for powering down a computer system while saving the state of the system at power down is disclosed. The system maintains the capability to suspend the execution of an application program operating on the system at any point and resuming execution of the application program at that same point at a later time. The time at which the system may be powered down and then powered back up again is totally arbitrary and depends only upon the user of the system. At the time the system is powered off, the contents of all active registers as well as the states of all I/O devices in the system are stored in a special save area of system memory. This special save area is provided with power during the suspended time in order to retain the state of the system at the time it was powered down. By using this special save suspend area, the main memory area of the system is available to any application programs independently of the system save memory requirements.

Abstract: A method for creating on-line presentations on a computer display using a complier, a compressor, and a processor. The complier converts control commands in source code format into object code format in order to specify how the information in an on-line presentation is to be presented on the display. The complier also creates a file identifying the image data to be used in the presentation. This file contains the names of the display units describing the image data used to indicate which of the uncompressed image data is to be operated upon by the compressor. The compressor formats and compresses the displayable picture elements of text and graphic shapes which have been used to create the on-line presentation. The processor then loads and executes the object code of the control commands with its corresponding picture elements of image data to create the on-line presentation. The control commands are generated totally separate from the image data.

Abstract: A method and apparatus are disclosed for enabling a diskette drive system to distinguish between diskettes and verify that the diskette currently in the drive is the correct one. Each diskette contains a file allocation table for controlling the allocation and deallocation of storage space on the diskette. Each time that the file allocation table on a diskette is accessed, i.e., read or written, a cyclic redundancy check (CRC) value for the file allocation table is calculated and stored. When checking the validity of a diskette, i.e., that the correct diskette is in the drive, a CRC value for the file allocation table of the currently loaded diskette is calculated and compared to the most recently stored CRC value. If the most recently calculated CRC value does not match the most recently stored CRC value, then this is an indication that the wrong diskette is currently in the diskette drive. A warning is then provided to the system user to change diskettes before a read or a write operation will be commenced.