Abstract:
A restarter is capable of recovering from a hung base unit from a remote location. The restarter includes a communication controller circuit connected to a network to receive a control command transmitted from a terminal unit; a detection circuit for achieving control command detection when a first control command is received by the communication controller circuit; and a switch which is subjected to on/off control exercised according to a detection output from the detection circuit. The switch is serially connected to a power supply line between a power input end of the base unit and a power supply end of the base unit. When a first control command is transmitted from the terminal unit, the switch is controlled during a predetermined period so that the status of the switch changes from ON to OFF and then back to ON in accordance with the detection output from the detection circuit.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     The present application claims priority from Japanese Patent Application No. JP 2004-352245 filed on Dec. 6, 2004, the disclosure of which is hereby incorporated by reference herein.  
       BACKGROUND OF THE INVENTION  
       [0002]     The present invention relates to a restarter that is used for recovery when a base unit hangs up.  
         [0003]     AV (Audio and Visual) and other electronic devices having a network function have been increasingly used. When an electronic device having a network function is used, it is possible to control its operation from a remote location and obtain information according to operation results at the remote location.  
         [0004]     When, for instance, an AV device having a network function is used in a hotel or other location away from home, it is possible to view or listen to content that is prepared at home. When, for instance, a monitor camera having a network function is used, it is possible to exercise remote control to change the orientation of the monitor camera or the degree of zooming and precisely display a target on a monitor screen.  
         [0005]     Related techniques are disclosed, for example, in Japanese Patent Laid-Open No. Hei 11-24801 or No. 2003-241861.  
         [0006]     However, the software executed by an electronic device having a network function may hang up for some reason or other in a situation where the device is controlled from a remote location. In such an instance, it is necessary to bring the hung software to a forced end. The electronic device cannot be used until the hung software is forcibly terminated.  
       SUMMARY OF THE INVENTION  
       [0007]     The present invention clears the above-mentioned trouble from a remote location and makes it possible to use the network function again.  
         [0008]     According to an embodiment of the present invention, there is provided a restarter which is connectable to a base unit that transmits desired data to a terminal unit via a network. The restarter includes a communication controller circuit connected to the network to receive a control command transmitted from the terminal unit; a detection circuit for achieving control command detection when a first control command is received by the communication controller circuit; and a switch which is subjected to on/off control that is exercised according to an output from the detection circuit.  
         [0009]     In this restarter, the switch may be serially connected to a power supply line between a power input end of the base unit and a power supply end of the base unit, and when a first control command is transmitted from the terminal unit, the switch may be controlled during a predetermined period so that the status of the switch changes from ON to OFF and then back to ON in accordance with the output from the detection circuit.  
         [0010]     Even when the base unit hangs up while the terminal unit is used at a remote location, the present invention makes it possible to restart the base unit from the currently used terminal unit and achieve recovery from the hangup.  
         [0011]     Further, since the base unit is turned off, turned back on, and then restarted, all components are properly initialized as is the case where the power is turned off and then back on during normal use. Therefore, the restart and the operation performed after the restart are proper. Furthermore, since the restarter can be constructed as a stand-alone unit and works when it is connected to a power supply line for the base unit, it is effective for an existing base unit. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0012]      FIG. 1  is a schematic diagram illustrating the present invention;  
         [0013]      FIG. 2  is a schematic diagram illustrating an AV device having a network function;  
         [0014]      FIG. 3  is a schematic diagram illustrating an embodiment of the present invention; and  
         [0015]      FIG. 4  is a schematic diagram illustrating another embodiment of the present invention.  
     
    
     DETAILED DESCRIPTION  
       [0000]     (1) Outline of an AV Device Having a Network Function  
         [0016]      FIG. 1  shows a typical use of an AV device that permits the user to freely view or listen to content, which is prepared at home, no matter whether the user is at home or at a remote location away from home.  FIG. 2  shows the outline of a typical configuration of the AV device. The AV device includes a base unit  100  and a portable monitor (portable display unit)  200 .  
         [0017]     The base unit  100  is installed, for instance, at home to supply various video signals and audio signals to the portable monitor  200 . The portable monitor  200  is a terminal for receiving video and audio from the base unit  100  and viewing or listening to the received video and audio at home or at a remote location. The reference numeral  200 A denotes a portable monitor for use at home. The reference numeral  200 B denotes a portable monitor for use at a remote location such as a hotel.  
         [0018]     As shown in  FIG. 2 , the base unit  100  incorporates a tuner circuit  101  for receiving a TV broadcast and is connected to an external AV device such as a DVD player  400 . Further, the base unit  100  includes a transceiver circuit  111  and a communication controller circuit  112 .  
         [0019]     The transceiver circuit  111  wirelessly connects the base unit  100  to portable monitor  200 A, and complies, for instance, with the IEEE (Institute of Electrical and Electronics Engineers) 802.11 standard. The communication controller circuit  112  establishes a connection to portable monitor  200 B through the Internet  600 . The communication controller circuit  112  is an LSI (Large Scale Integration) for connecting the base unit  100  to the Internet  600  for the purpose of establishing network communication. The communication controller circuit  112  analyzes packets that are transmitted/received in accordance with the TCP/IP (Transmission Control Protocol/Internet Protocol), and exercises control over data selection, transmission, and reception.  
         [0020]     The base unit  100  includes a microcomputer  120 . The microcomputer  120  controls the operations of various components of the base unit  100 . It has a nonvolatile memory (not shown) for storing various data. A commercial AC voltage is supplied to a power supply circuit  133  via a power plug  131  and a main power switch  132 . A predetermined DC voltage is then derived from the supplied commercial AC voltage and supplied to various circuits as their operating voltage.  
         [0021]     The communication controller circuit  112  is connected to the Internet  600 , for instance, via a broadband router  501 , an ADSL (Asymmetric Digital Subscriber Line)  502 , and an ISP (Internet Service Provider)  503 .  
         [0022]     The portable monitor  200  includes a transceiver circuit  211  and a communication controller circuit  212 . The transceiver circuit  211  makes a pair with the transceiver circuit  111  of the base unit  100  to wirelessly connect the base unit  100  to the portable monitor  200 . The communication controller circuit  212  of the portable monitor  200  is identical with the communication controller circuit  112  of the base unit  100 .  
         [0023]     The portable monitor  200  also includes an LCD (Liquid Crystal Display)  213  and a speaker  214 , which are used for video/audio output, and a touch panel  215 . The touch panel  215  is used to exercise remote control over the base unit  100  from the portable monitor  200 . The touch panel  215  is transparent and laid over a display surface of the LCD  213 . The reference numeral  216  denotes a hardware-based operating control section, which includes, for instance, a menu button and channel selector buttons.  
         [0024]     Further, the portable monitor  200  includes a microcomputer  220  for controlling the operations of various components of the base unit  100  and portable monitor  200 . The portable monitor  200  operates from a rechargeable battery (not shown).  
         [0000]     (2) Operations of the Base Unit  100  and Portable Monitor  200   
         [0025]     When the status of the power switch  132  for the base unit  100  is changed from OFF to ON, A DC voltage is output from the power supply circuit  133  and supplied to various circuits as their operating voltage. This causes the microcomputer  120  to start up a predetermined program. When the program starts up, various sections are initialized in accordance with the data stored in the nonvolatile memory of the microcomputer  120 . Therefore, the base unit  100  is subsequently in the steady state.  
         [0026]     When the menu button, which is included in the operating control section  216  of the portable monitor  200 , is pressed, the microcomputer  220  displays a menu on the LCD  213 . When the touch panel  215  is operated while the menu is displayed, the LCD  213  switches from the menu screen to various setup screens.  
         [0027]     If, for instance, the menu screen is manipulated to select a setup screen for specifying whether the connection between the base unit  100  and portable monitor  200  is to be established wirelessly or through the Internet, the setup screen opens. When a connection method is selected from the setup screen, the result of selection is stored in the nonvolatile memory (not shown) of the microcomputer  220 .  
         [0028]     The portable monitor  200  can access the base unit  100  as described below and use the content supplied from the base unit  100 .  
         [0000]     (2-1) When the Portable Monitor  200  is Used at Home  
         [0029]     This is a case where the base unit  100  is wirelessly connected to the portable monitor  200 . In this case, when an operating control button or icon displayed on the LCD  213  of portable monitor  200 A is operated, a control command (including data as needed) is formulated by portable monitor  200 A in accordance with the operation performed and wirelessly transmitted to the base unit  100  via the transceiver circuit  211 .  
         [0030]     In the base unit  100 , the control command transmitted from portable monitor  200 A is received by the transceiver circuit  111  and supplied to the microcomputer  120 . Consequently, the base unit  100  is controlled in accordance with the operation performed with portable monitor  200 A. For example, the broadcast on a target TV channel is received or the base unit  100  remotely controls the DVD player  400  to perform a reproduction operation. The video and audio signals obtained in this manner are wirelessly transmitted to portable monitor  200 A via the transceiver circuit  111 .  
         [0031]     In portable monitor  200 A, the video and audio signals transmitted from the base unit  100  are received by the transceiver circuit  211  and supplied to the LCD  213  and speaker  214 . The LCD  213  and speaker  214  then output target video and audio. Consequently, portable monitor  200 A allows the user to view or listen to the content prepared in the base unit  100 .  
         [0000]     (2-2) When the Portable Monitor  200  is Used at a Remote Location  
         [0032]     This is a case where the base unit  100  is connected to the portable monitor  200  through the Internet. In this case, portable monitor  200 B must be connected to the Internet via the communication controller circuit  212 . When an operating control button or icon displayed on the LCD  213  of portable monitor  200 B is operated, a control command is formulated by the microcomputer  220  in accordance with the operation performed and transmitted to the Internet  600  via the communication controller circuit  212  together with an IP address for designating the base unit  100 .  
         [0033]     In the base unit  100 , the control command transmitted from portable monitor  200 B is supplied to the microcomputer  120  via the communication controller circuit  112 . The base unit  100  is then controlled in accordance with the operation performed with portable monitor  200 B. Further, the target video signal and audio signal are transmitted, in the form of stream data, to the Internet  600  via the communication controller circuit  112  together with an IP address for designating portable monitor  200 B.  
         [0034]     In portable monitor  200 B, the video and audio signals transmitted from the base unit  100  are obtained from the communication controller circuit  212 . The LCD  213  and speaker  214  then output target video and audio. As a result, the content prepared at home can be viewed or listened to at a remote location through the Internet.  
         [0000]     (3) Restarter  
         [0000]     (3-1) Restarter Configuration  
         [0035]     The microcomputer  120  in the base unit  100  may hang up for some reason or other. In such an instance, it is necessary to bring the hung microcomputer  120  to a forced end as described earlier.  
         [0036]     In  FIG. 3 , the reference numeral  300  denotes a restarter for brining the hung microcomputer  120  to a forced end and restarting it from the portable monitor  200 .  
         [0037]     The restarter  300  includes a power plug  301 , a normally-open switch  302 , and an outlet  303 . The normally-open switch  302  is serially connected to a power supply line between the power plug  301  and outlet  303 . The power plug  301  is connected, for instance, to a wall outlet (not shown) to receive a commercial AC voltage supply. The power plug  131  of the base unit  100  is connected to the outlet  303 .  
         [0038]     The restarter also includes a communication controller circuit  312 , a microcomputer  313 , and a relay  314 . The communication controller circuit  312  is identical with communication controller circuits  112  and  212 . It is connected to a modular jack  311  and to the microcomputer  313 .  
         [0039]     The microcomputer  313  is connected to the portable monitor  200  via the communication controller circuit  312  and the Internet  600 . The microcomputer  313  exchanges various control commands with the portable monitor  200 . Further, the microcomputer  313  detects and determines the control commands as described later.  
         [0040]     The relay  314  is driven in accordance with an output from the microcomputer  313 . For example, a normally-open contact of the relay  314  is used as the normally-open switch  302 . The commercial AC voltage supplied to the power plug  301  is forwarded to a power supply circuit  320 . A predetermined DC voltage is derived from the commercial AC voltage and supplied to various circuits as their operating voltage. The modular jack  311  is connected to the router  501  through a LAN (Local Area Network) cable  351 .  
         [0041]     A unique IP address is assigned to the restarter  300 . This IP address is stored in the nonvolatile memory (not shown) of the microcomputer  313 .  
         [0000]     (3-2) Operation of the Restarter  300   
         [0042]     In the steady state, the microcomputer  313  drives the relay  314  to turn ON its switch  302 . Consequently, the commercial AC voltage supplied to the power plug  301  is supplied to the power plug  131  of the base unit  100  via the switch  302  and outlet  303 .  
         [0043]     Therefore, when the power switch  132  of the base unit  100  is ON, the process described under (2) is performed in the base unit  100  so that the base unit  100  and portable monitor  200  can be used.  
         [0000]     (3-2-1) Recovering from a Hung Base Unit  100  from a Remote Location  
         [0044]     If the base unit  100  hangs up for some reason while the portable monitor  200  is used at a remote location, the menu button  216  of the currently used portable monitor  200  should be operated to display a menu on the LCD  213 . “Restart base unit” should then be chosen from the menu.  
         [0045]     The microcomputer  220  then generates a control command that issues instructions for restarting the base unit  100 . This control command is transmitted from the portable monitor  200  to the Internet  600  with the IP address of the restarter  300  specified. The control command is received by the restarter  300  and output from the communication controller circuit  312 . Further, the microcomputer  313  detects or determines that the control command invokes a restart.  
         [0046]     As a result, the microcomputer  313  does not drive the relay  314  for a predetermined period τ. The switch  302  is OFF during this period τ. Therefore, the base unit  100  is OFF during the period τ so that the software executed by the base unit  100  comes to a forced end.  
         [0047]     When the period τ elapses, the microcomputer  313  drives the relay  314 , thereby turning ON the switch  302 . Therefore, the base unit  100  is turned back ON. Thus, preinstalled software starts up as is the case where the power switch  132  of the base unit  100  is turned ON.  
         [0048]     When the software starts up, various components are initialized in accordance with the data stored in the nonvolatile memory of the microcomputer  120 . Therefore, the base unit  100  is subsequently in the steady state so that the portable monitor  200  can access the base unit  100 .  
         [0049]     Even if the base unit  100  hangs up while the portable monitor  200  is used at a remote location, it is possible to restart the base unit  100  from the currently used portable monitor  200 , which is at a remote location, and recover from the hung base unit  100 .  
         [0000]     (3-2-2) Turning OFF the Base Unit  100  from a Remote Location  
         [0050]     When the base unit  100  is not going to be used for a prolonged period of time although the portable monitor  200  is used at a remote location, the menu button  216  of the portable monitor  200  should be operated to display a menu on the LCD  213 . “Turn OFF base unit” should then be chosen from the menu.  
         [0051]     The portable monitor  200  then generates a control command that issues instructions for turning OFF the power. This control command is transmitted to the Internet  600  with the IP address of the restarter  300  specified. The control command is received by the restarter  300  and output from the communication controller circuit  312 . Further, the microcomputer  313  detects or determines that the control command turns OFF the power. Consequently, the microcomputer  313  does not drive the relay  314 . Thus, the switch  302  is subsequently OFF.  
         [0052]     The commercial AC voltage supply to the base unit  100  is then shut off so that the base unit  100  is OFF. Since the base unit  100  can be turned OFF from a remote location, it is possible to minimize the power consumption.  
         [0000]     (3-2-3) Turning ON the Base Unit  100  from a Remote Location  
         [0053]     When the base unit  100  is to be turned ON after it was turned OFF from a remote location as described under (3-2-2), the menu button  216  of the portable monitor  200  should be operated to display a menu on the LCD  213 . “Turn ON base unit” should then be chosen from the menu.  
         [0054]     The portable monitor  200  then generates a control command that issues instructions for turning ON the power. This control command is transmitted to the Internet  600  with the IP address of the restarter  300  specified. The control command is received by the restarter  300  and output from the communication controller circuit  312 . Further, the microcomputer  313  detects or determines that the control command turns ON the power. Consequently, the microcomputer  313  drives the relay  314 . Thus, the switch  302  is subsequently ON.  
         [0055]     Then, the base unit  100  is energized again, and preinstalled software starts up as is the case where the power switch  132  is turned ON. As a result, the base unit  100  is in the steady state as is the case where the period τ is elapsed as described under (3-2-1), and the portable monitor  200  can access the base unit  100 .  
         [0056]     Even when the base unit  100  is turned OFF for the purpose of minimizing the power consumption, it can be turned back ON from a remote location and used as the base unit  100  as described above.  
         [0000]     (4) Conclusion  
         [0057]     Even if the base unit  100  hangs up while the portable monitor  200  is used at a remote location, the restarter  300  described above enables the currently used portable monitor  200  to recover from the hung base unit  100  by restarting it.  
         [0058]     Further, since the base unit  100  is turned off, turned back on, and then restarted, all components are properly initialized as is the case where the power is turned off and then back on during normal use. Therefore, the restart and the operation performed after the restart are proper. Furthermore, since the restarter  300  can be constructed as a stand-alone unit as shown in  FIG. 3  and works when it is connected to the power supply line for the base unit  100 , it is effective for an existing base unit  100 .  
         [0000]     (5) Another Embodiment of the Restarter  300   
         [0059]      FIG. 4  illustrates a configuration in which the restarter  300  is constructed as a restarter circuit  310  and incorporated in the base unit  100 . As is the case described under (3), this configuration also includes the communication controller circuit  312 , microcomputer  313 , relay  314 , and power supply circuit  320 . Communication controller circuits  122  and  312  are connected to a modular jack  113  via a hub circuit  315  and further connected to the router  501 .  
         [0060]     As is the case described under (3), the portable monitor  200  can therefore recover from a hung base unit  100  from a remote location, turn OFF the base unit  100  from a remote location, and turn ON the base unit  100  from a remote location.  
         [0000]     (6) Other  
         [0061]     The base unit  100  and portable monitor  200 , which have been described above, can be interconnected through a home LAN. Even if the base unit  100  hangs up in a situation where the above configuration is employed, the portable monitor  200  can restart the base unit  100 .  
         [0062]     It should be understood by those skilled in the art that various modifications, combinations, sub-combinations, and alterations may occur depending on design requirements and other factors insofar as they are within the scope of the appended claims or the equivalents thereof.