Computer system with power control based on the operational status of terminals

• US 4,809,163 A
• Filed: 04/14/1987
• Issued: 02/28/1989
• Est. Priority Date: 05/18/1983
• Status: Expired due to Term

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Ohki, Masaru, Kuwahara, Yutaka, Hirosawa, Toshio
• Primary Examiner(s): Zache, Raulfe B.
• Assistant Examiner(s): Harrell, Robert B.
• Application Number:
  US07/038,307
• Time in Patent Office: 686 Days
• Field of Search: 379/252, 379/234, 379/379, 379/22, 364/491, 364/492, 364/493, 364/700, 364/200 MS File, 364/300 MS File, 364/900 MS File
• US Class Current: 713/323
• CPC Class Codes: G06F 1/26 Power supply means, e.g. regulation thereof for memories G11C
• CPC Class Codes: G06F 1/3215 Monitoring of peripheral devices

Abstract

A computer system as a processor which operates under control of an operating system stored in memory to execute programs in response to commands received from operator terminals. Power is supplied to the processor from a power control circuit, and a terminal status-monitoring circuit operating under its own power supply monitors the operational status of the operator terminals and causes power to be supplied to the processor from the power control circuit when any one of the operator terminals has been turned on. When all of the operator terminals have been turned off, a command is sent to the processor from the power control circuit to initiate termination processing after which power supply is removed from the processor.

Claims

1. A computer system, comprising:

a central computer which performs concurrently executing selected ones of plural programs;

a plurality of operator terminal means connected to said computer for exchanging commands and data required to request said computer to execute a selected one of said plural programs between said computer and each terminal means so as to receive and output data corresponding to results of execution of the selected one of said plural programs;

monitor means connected to said plurality of terminal means for detecting a first condition that at least one of the plurality of terminal means is in an operational status, and a second condition that all of the terminal means are in a non-operational status; and

control means connected to said monitor means and said computer and responsive to detection of said first condition for starting supply of power to said computer to turn on said computer and for thereafter instructing said computer to execute initialization processing for an operating system program included in said computer, and responsive to the detection of said second condition for instructing said computer to execute termination processing for the operating system program and for thereafter terminating the supply of power to said computer so as to turn off the computer.

2. A computer system according to claim 1, where in said control means includes means connected to said monitor means and responsive to detection of the second condition after starting of power supply to said computer and before completion of execution of the initialization processing by said computer for instructing said computer to execute to execute the termination processing, after completion of the execution of the initialization processing by said computer.

3. A computer system according to claim 1, wherein said control means includes means connected to said monitor means and responsive to another detection of the first condition after detection of the second condition and before completing execution of the termination processing by said computer for instructing said computer to execute the initialization processing after completion of the termination processing

4. A computer system according to claim 1, wherein said control means includes means connected to said monitor means and responsive to detection of the second condition after starting of power supply to said computer and before completion of execution of the initialization processing by said computer for instructing said computer to execute the termination processing, after completion of the execution of the initialization processing by said computer and responsive to another detection of the first condition after detection of the second condition and before completing execution of the termination processing by said computer for instructing said computer to execute the initialization processing after completion of the termination processing.

5. A computer system according to claim 1, wherein said monitor means includes:

a plurality of detect means, each corresponding to one of the plurality of terminal means, respectively, for detecting an operation status thereof and means connected to said plurality of detect means for detecting the first and second conditions in response to outputs of said plurality of detect means.

6. A computer system according to claim 5, wherein each detect means includes means connected to switch means provided in said corresponding terminal means for detecting the operation status thereof based on whether the switch means turns on or off, wherein said switch means is an operator power switch means for controlling power supply to said corresponding terminal means.

7. A computer system according to claim 6, wherein each terminal means comprises video data terminal means including keyboard means connected to a video display means.

8. A computer system according to claim 4, wherein said monitor means includes:

a plurality of detect means, each for a corresponding one of the plurality of terminal means, for detecting an operational status of the correspond terminal means and means connected to said plurality of detect means for detecting the first and second conditions in response to outputs of said plurality of detect means.

9. A computer system according to claim 8, wherein each detect means includes means connected to switch means provided in said corresponding terminal means for detecting the operation status thereof based upon whether the switch means turns on or off, wherein said switch means is an operator power switch means for controlling power supply to said corresponding terminal means.

10. A computer system according to claim 9, wherein each terminal means comprises video data terminal means including keyboard means connected to a video display means.

16. A computer system according to claim 1, wherein said control means includes a power supply means for supplying said power to said computer.

11. A computer system, comprising:

a central computer which performs concurrently executing selected ones of plural programs;

power supply means connected to said central computer for supplying power thereto;

a plurality of operator terminal means connected to said central computer for exchanging commands and data between said central computer and each terminal means so as to request said central computer to execute selected ones of said plural programs and so as to receive and output data corresponding to results of execution of the selected ones of said plural programs;

monitor means connected to said plurality of terminal means for monitoring an on or off operational status of said plurality of terminal means; and

control means connected to said monitor means and said power supply means for instructing said power supply means to start a supply of power to said central computer to turn on said central computer when said monitor means detects that any one of said plurality of terminal means is put into said on operational status and for instructing said power supply means to terminate the supply of power to said central computer when the monitor means detects that none of said terminal means is in said on operational status;

wherein said power supply means includes means connected to said control means and responsive to one command provided from said control means to effect starting of the supply of power for instructing said central computer to execute initialization processing for an operating system program include in said central computer after start of the supply of power, and responsive to another command provided from said control means to effect terminating of the supply of power instructing said central computer to execute termination processing for the operating system program before termination of the supply of power thereto.

12. A computer system according to claim 11, wherein each of said terminal means includes switch means to control said operational status, and said monitor means includes means for detecting whether or not said switch means provided in each of said plurality of terminal means is turned on in order to monitor the operational status of each terminal means.

13. A computer system according to claim 12, wherein said switch means comprises power switch means for controlling the supply of power to each terminal means from said power supply means.

14. A computer system according to claim 11, wherein said power supply means includes means connected to said control means and responsive to receipt of said another command to effect terminating of the supply of power after receipt of an instruction to effect starting of the supply of power and before completion of execution of the initialization processing by said central computer required by receipt of said one command to effect starting of the supply of power for providing said central computer with an instruction to effect execution of the termination processing, after completion of the execution of the initialization processing by said central computer.

15. A computer system according to claim 11, wherein said power supply means includes means connected to said control means and responsive to receipt of said one command from said control means to effect starting of the supply of power, after receipt of said another command to effect termination of the supply of power and before completion of executing the termination processing by said central computer required by receipt of said another command to effect termination of the supply of power, for providing said central computer with the command to effect execution of the initialization processing for the operating system program after completion of the termination processing by said central computer.

17. A method of automatically controlling on/off status of a main power supply to a central computer system including a plurality of terminal devices which can request processing, comprising the steps, performed entirely by a monitor circuit in computer system in an automatic manner of:

monitoring said plurality of term request processing;

detecting a power-on status of at least one of said plurality of terminal devices;

starting the power supply to said computer system in response to the detection of a power-on status of at least one of said plurality of terminal devices;

detecting a power-off status of all of said plurality of terminal devices;

terminating the power supply to all of said plurality of terminal devices in response to the detection of a power-off status of all of said plurality of terminal devices.

18. A method of automatically controlling on/off status of a main power supply to a central computer system including a plurality of terminal devices which can request processing, comprising the steps, performed entirely by a monitor circuit in said computer system in an automatic manner, of:

monitoring each of said plurality of terminal means

detecting a first condition that at least one of the plurality of terminal means is in an operational status;

starting a power supply to said computer in response to detection of said first condition;

instructing said computer to execute an initialization processing for an operating system program in said computer;

detecting a second condition that all of said plurality of terminal means are in a non-operational status;

instructing said computer to execute a termination processing for said operating system program in response to detection of said second condition;

terminating the power supply to said computer so as to turn off said computer after execution of said termination processing.