Abstract:
This invention relates to an electronic device including a lock switch which defines activation permission of the power supply of the electronic device, and a unit which receives an activation instruction from software and invalidates the received activation instruction when the lock switch permits activation.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
         [0001]    This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2002-328409, filed Nov. 12, 2002, the entire contents of which are incorporated herein by reference.  
         BACKGROUND OF THE INVENTION  
         [0002]    1. Field of the Invention  
           [0003]    The present invention relates to an electronic device and, more particularly, to an electronic device capable of preventing, by software, activation of the electronic device from software.  
           [0004]    2. Description of the Related Art  
           [0005]    Recently, the use of electronic devices which generate electromagnetic waves that influence other electronic devices tends to be inhibited in taking off/landing an airplane or in a hospital or the like. Even a portable personal computer must be powered off in taking off/landing an airplane.  
           [0006]    Even if the user powers off an electronic device at this request, the electronic device may be erroneously powered on (e.g., the panel may be erroneously opened to power on the electronic device by a panel switch). Also, the electronic device may be powered on by a function installed for convenience (e.g., the electronic device is powered on by an ON signal from a modem or timer). The user may be held responsible in such case.  
           [0007]    To solve this problem, a technique of attaching a power supply lock switch to an electronic device and even if the panel switch is erroneously turned on or a power ON signal is output from a modem or timer, invalidating the switch or signal by hardware is disclosed (Jpn. Pat. Appln. KOKAI Publication No. 2002-99359 (p. 4, FIG. 1).  
           [0008]    According to the conventional technique, the power supply switch, the panel switch, or an ON signal from the modem or timer is invalidated by hardware. However, the electronic device is activated (including wakeup: this also applies to the following description) by another factor.  
           [0009]    For example, the electronic device has a function of temporarily activating it and performing hibernation (resume) when the battery becomes low. In this case, a conventional electronic device cannot prevent activation.  
           [0010]    Such activation function can be permitted/inhibited via a user interface in an OS (Operating System). In the OFF or suspend state, activation setting cannot be done. The user must temporarily activate the electronic device and inhibit the setting via the user interface in the OS.  
         BRIEF SUMMARY OF THE INVENTION  
         [0011]    According to the embodiment of the present invention, there is provided an electronic device comprising: means for inhibiting activation of the electronic device; means for holding information representing whether activation is inhibited by the inhibiting means; and means for executing activation or activation inhibition of the electronic device on the basis of the information stored in the storage means when an activation instruction is generated in the electronic device.  
           [0012]    According to the embodiment of the present invention, there is provided an electronic device comprising: means for inhibiting activation of the electronic device; and means for, when an activation instruction is generated from software which runs in the electronic device, deciding whether activation of the electronic device is inhibited by the inhibiting means, and when activation is inhibited, inhibiting activation of the electronic device. 
       
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING  
       [0013]    The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate presently preferred embodiments of the invention, and together with the general description given above and the detailed description of the preferred embodiments given below, serve to explain the principles of the invention.  
         [0014]    [0014]FIG. 1 is a block diagram showing the internal system of a personal computer having a lock switch according to an embodiment of the present invention; and  
         [0015]    [0015]FIG. 2 is a flow chart for explaining EC operation of the PC according to the embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0016]    A notebook type personal computer according to a preferred embodiment of the present invention will be described below with reference to the several views of the accompanying drawing.  
         [0017]    [0017]FIG. 1 shows the internal system of a personal computer having a lock switch according to the embodiment of the present invention. The computer system shown in FIG. 1 is a battery-drivable notebook type personal computer (to be referred to as a PC hereinafter). The personal computer comprises a power supply controller (PSC)  22  which controls power supplied from a battery (not shown). The power supply controller (PSC)  22  supplies various power supply voltages from a voltage output terminal  22 A to respective parts of the system.  
         [0018]    In addition to the power supply controller (PSC)  22 , as shown in FIG. 1, the PC system comprises a PCI bus  2 , ISA bus  3 , CPU module  11 , main memory  12 , VGA controller  10 , I/O controller  15 , PCI interface bridge (PCI I/F)  17 , HDD  18 , embedded controller (EC)  21 , keyboard controller (KBC)  23 , and keyboard (KB)  24 .  
         [0019]    The CPU module  11  executes operation control of the whole system and data processing. The CPU module  11  incorporates a CPU, a cache, and a memory controller for controlling the main memory  12 .  
         [0020]    The main memory  12  is used as the main storage of the system. The main memory  12  stores an operating system, an application program to be processed, and user data created by the application program.  
         [0021]    The VGA controller  10  controls an LCD  9  used as the display monitor of the system, and an external CRT.  
         [0022]    The I/O controller  15  is a gate array for controlling various I/O devices in the PC. The I/O controller  15  controls devices connected to various I/O connectors such as a serial port  26 , parallel port  27 , and USB port  28  which are formed on the back surface of the PC main body.  
         [0023]    The PCI interface bridge (PCI I/F)  17  is a gate array implemented by a 1-chip LSI. The PCI I/F  17  incorporates a bridge function which connects the PCI bus  2  and ISA bus  3  in two ways. The PCI I/F  17  further incorporates an IDE controller for controlling the HDD  18 . The PCI I/F  17  is connected to a real time clock (RTC)  6 .  
         [0024]    The real time clock (RTC)  6  has a function of shifting the PC main body in the sleep or OFF state to the ON state at a predetermined time designated by the user. The PCI I/F bridge  17  detects the predetermined time, and supplies an activation (including wakeup: this also applies to the following description) request to the embedded controller (EC)  21 .  
         [0025]    The PCI I/F bridge  17  detects whether a modem  7  has received a ringing signal upon termination, and if so, outputs an activation request to the EC  21 .  
         [0026]    In response to this activation request, the embedded controller (EC)  21  supplies a power supply request to the power supply controller  22 , shifting the PC main body to the ON state.  
         [0027]    The embedded controller (EC)  21  manages the power supply state of the PC main body in cooperation with the power supply controller (PSC)  22 . The embedded controller (EC)  21  and power supply controller (PSC)  22  keep receiving operating power even if the PC main body is powered off and shifts to the sleep state or OFF state. The embedded controller (EC)  21  has a function of controlling the power supply controller (PSC)  22  in response to detection of generation of an activation factor, and notifying a system BIOS of the generated activation factor as a power management event.  
         [0028]    The power supply controller (PSC)  22  is connected to a lock switch  31  and power supply switch  32 . In normal operation, when the power supply switch  32  is pressed, the power supply controller (PSC)  22  supplies an operating voltage to each part of the PC main body. The PC main body in the sleep or OFF state shifts to the ON state.  
         [0029]    The system shown in FIG. 1 comprises the lock switch  31  which prevents the PC main body from operating due to an external factor or erroneously in a situation in which the operation of the PC main body is unpreferable.  
         [0030]    In an unlocked state in which the lock switch  31  is not turned on, if either the power supply switch  32  or lock switch  31  is pressed, the power supply controller (PSC)  22  is instructed to supply power. The power supply controller (PSC)  22  supplies power to each part of the PC, shifting the PC main body in the sleep or OFF state to the ON state. Similarly, if the PCI I/F bridge  17  detects a device activation factor for the real time clock (RTC)  6 , modem  7 , or the like, the PCI I/F bridge  17  outputs an activation request to the EC  21 . The EC  21  outputs a power supply request to the power supply controller (PSC)  22 . The power supply controller (PSC)  22  supplies power to each part of the PC, shifting the PC main body in the sleep or OFF state to the ON state.  
         [0031]    To the contrary, when the lock switch  31  is turned on to set a locked state, no power supply request is supplied to the power supply controller  22  even if either the lock switch  31  or power supply switch  32  is pressed. The PC main body maintains the sleep or OFF state. Even if a device activation factor for the real time clock (RTC)  6 , modem  7 , or the like is detected and the EC  21  receives an activation request from the PCI I/F bridge  17 , no power supply request is output to the power supply controller  22 , and the PC main body maintains the sleep or OFF state.  
         [0032]    Even upon reception of another software factor such as an activation request accompanied by hibernation which is performed in correspondence with a low-battery state, no ON signal is supplied to the power supply controller  22  when the lock switch  31  is in the locked state. The PC main body maintains the sleep or OFF state.  
         [0033]    The EC  21  comprises a register  33 . The register  33  stores information representing the locked/unlocked state of the lock switch  31 . The EC  21  decides the locked/unlocked state of the lock switch  31  on the basis of information stored in the register  33 .  
         [0034]    EC operation of the PC according to the embodiment of the present invention will be explained with reference to the flow chart of FIG. 2.  
         [0035]    Operation when an activation request is output in the sleep or OFF state of the PC will be described.  
         [0036]    The EC  21  decides whether activation requests based on software and hardware factors have been issued (S 1 ). As for activation requests to the EC  21  from the RTC  6  and a device connected to the PCI bus  2 , the PCI I/F bridge  17  detects the activation requests from the RTC  6  and the device connected to the PCI bus  2 , and requests activation of the EC  21 .  
         [0037]    If YES in S 1 , the EC  21  decides whether the lock switch  31  is in the locked state (S 2 ).  
         [0038]    If YES in S 2 , the EC  21  invalidates the received activation request (S 3 ), and returns to processing in S 1 . That is, the EC  21  invalidates all activation requests based on hardware and software factors on the basis of the state of the lock switch. System activation can, therefore, be completely prevented.  
         [0039]    If NO in S 2 , the EC  21  permits the power supply controller  22  to supply power, and power is supplied to each part of the PC (S 4 ).  
         [0040]    The EC  21  permits the PCI I/F bridge  17  to activate the CPU (S 5 ), and then the system is activated (S 6 ).  
         [0041]    In the PC according to the embodiment of the present invention, the EC  21  decides the state of the lock switch and invalidates an activation request. Activation based on all hardware and software factors can be prevented.  
         [0042]    The present invention is not limited to the above embodiment, and can be variously modified without departing from the spirit and scope of the invention in practical use.  
         [0043]    Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.