Abstract:
An equipment control apparatus capable of improving the command communication efficiency, wherein the equipment control apparatus ( 1 ) is provided with a receiver ( 11 ) for receiving an operation code transmitted from an operation device ( 3 ), and a processing unit ( 14 ). When the receiver ( 11 ) receives the operation code, the processing unit ( 14 ) determines whether or not the target source equipment ( 2 ) is compatible with the pass through control of the operation code, and upon determining that the source equipment ( 2 ) is incompatible, the processing unit ( 14 ) stops transmitting the command for transferring the operation code to the source equipment ( 2 ).

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to a device controlling apparatus. More particularly, the present invention relates to a device controlling apparatus to which a plurality of source devices are connected and which controls the connected source devices using commands. 
       BACKGROUND ART 
       [0002]    HDMI (High-Definition Multimedia Interface) is one of multimedia interfaces. With this HDMI, CEC (Consumer Electronics Control) is standardized. This CEC involves bus communication, and various commands are defined in CEC. CEC allows individual vendors to prepare a certain range of commands on their own, apart from commands defined according to the HDMI standard. Using such CEC commands, a device controlling apparatus (i.e. sink device) controls each of a plurality of source devices (for example, audio-visual devices) connected through HDMI cables (see, for example, Non-Patent Literature 1). 
         [0003]    As described above, vendors of source devices can define their own commands. Therefore, there are cases where CEC-compliant source devices cannot interpret commands from connected sink devices. In view of the above background, methods for communicating vendor-specific commands between source devices and sink devices of different vendors have been proposed (see, for example, Patent Literature 1). 
       Citation List 
     Patent Literature 
       [0004]    PTL 1: Japanese Patent Application Laid-Open No.2007-97095 
       Non-Patent Literature 
       [0005]    Non-PTL 1: High-Definition Multimedia Interface Specification Version 1.3a 
       DISCLOSURE OF INVENTION 
     Problems to be Solved by the Invention 
       [0006]    Here, CEC is not an essential protocol of HDMI, and therefore there are cases where source devices are non-CEC-compliant. Further, there are cases where vendor-specific CEC commands are implemented in sink devices and source devices. In view of above, there are cases where sink devices cannot control source devices because the source devices do not make responses when receiving CEC commands. 
         [0007]    Further, the transmission rate of CEC is low at 400 bps, and therefore communication between devices that cannot be controlled by CEC commands interferes with communication between other connected devices and deteriorates communication efficiency. 
         [0008]    It is therefore an object of the present invention to provide a device controlling apparatus that can improve the communication efficiency of CEC commands. 
       Solution to Problem 
       [0009]    To achieve the above object, an aspect of the present invention that is a device controlling apparatus has: a receiver that receives an operation code transmitted from an operator; a decision processing section that, after the receiver receives the operation code, decides whether or not a target source device complies with pass-through control based on the operation code; and a stopping processing section that, after the decision processing section decides that the source device does not comply with the pass-through control based on the operation code, stops transmitting a command for forwarding the operation code, to the source device. 
       Advantageous Effects of Invention 
       [0010]    When the source device that does not comply with pass-through control is found, the above device controlling apparatus stops transmitting CEC commands to this source device to prevent CEC commands from being transmitted unnecessarily, and improves the communication efficiency of CEC commands. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0011]      FIG. 1  is a block diagram showing a configuration of a device controlling apparatus  1  according to an embodiment of the present invention; 
           [0012]      FIG. 2  is a flowchart showing processing in the device controlling apparatus  1  when a source device  2  is connected; 
           [0013]      FIG. 3  shows a message M 1  that is displayed on a display  13  shown in  FIG. 1 ; 
           [0014]      FIG. 4  is a sequence chart showing exchange of CEC commands in the CEC compliance/non-compliance check process; 
           [0015]      FIG. 5  is a flowchart showing the processing in the device controlling apparatus  1  after an operator (i.e. remote controller)  3  is operated; 
           [0016]      FIG. 6  is a sequence chart showing the first half of exchange of CEC commands in the CEC remote controller pass-through control compliance/non-compliance check process; 
           [0017]      FIG. 7  is a sequence chart showing the second half of exchange of CEC commands in the CEC remote controller pass-through control compliance/non-compliance check process; 
           [0018]      FIG. 8  is a flowchart showing an alternative example of the processing in the device controlling apparatus  1  after the operator (i.e. remote controller)  3  is operated; and 
           [0019]      FIG. 9  shows an alternative example of the message M 1  that is displayed on the display  13  shown in  FIG. 1 . 
       
    
    
     DESCRIPTION OF EMBODIMENTS 
       [0020]      FIG. 1  is a block diagram showing the configuration of a device controlling apparatus (i.e. sink device)  1  according to an embodiment of the present invention. Further,  FIG. 1  shows at least one source device  2  (in this figure, sources  2 A to  2 C are shown) and an operator  3 , as peripheral equipment of the device controlling apparatus  1 . The source device  2  and the operator  3  will be explained below before the device controlling apparatus  1  will be explained in detail. 
         [0021]    Each source device  2  enables HDMI (High-Definition Multimedia Interface) output and is, for example, a digital movie camera. Each source device  2  is connected with the device controlling apparatus  1  through an HDMI cable, and sends video signals to the device controlling apparatus  1  through this HDMI cable. 
         [0022]    With the present embodiment, the operator  3  is a remote controller that allows the user remotely control each source device  2  through the device controlling apparatus  1 , and has, for example, buttons to which various kinds of functions are assigned. When the user operates a button, the operator  3  generates the operation code assigned to the button that is operated, modulates an infrared signal by the generated operation code and then outputs the signal to the device controlling apparatus  1 . 
         [0023]    Next, the device controlling apparatus  1  will be explained. The device controlling apparatus  1  has a receiver  11 , an external interface (I/F)  12 , a display  13  and a processing section  14 . 
         [0024]    The receiver  11  receives as input light of the infrared signal outputted from the operator  3 , demodulates the received infrared signal and, by this means, acquires the operation code. The acquired operation code is sent to the processing section  14 . 
         [0025]    The external I/F  12  has a plurality of HDMI ports, and each port can be connected with one source device  2 . The external I/F  12  receives as input video signals sent from the source device  2  connected to each port. The external I/F  12  selects at least one of the input video signals, and outputs this signal to the display  13 . Further, the external I/F  12  selects the video signal that must be outputted to the display  13 , according to the setting from the processing section  14 . 
         [0026]    Additionally, the external I/F  12  receives CEC commands sent from the processing section  14  as control commands, sends the video signal to the source device  2  that is outputting signals, and sends the CEC commands sent from the source device  2  that is outputting video signals, to the processing section  14 . 
         [0027]    The display  13  displays an image according to the video signal from the external I/F  12 . Additionally, the display  13  displays messages according to message signals from the processing section  14 . 
         [0028]    The processing section  14  controls each section forming the device controlling apparatus  1 . Additionally, the processing section  14  controls the transmission of CEC commands. 
         [0029]    Next, processing in the device controlling apparatus  1  will be explained first with reference to  FIG. 2 .  FIG. 2  is a flowchart showing processing in the device controlling apparatus  1  when the source device  2  is connected. 
         [0030]    In  FIG. 2 , the processing section  14  decides whether or not the source device  2  is connected to any of the ports of the external I/F  12  (step S 201 ). Detecting +5V power of an HDMI connector is one specific method of making decisions in step S 201 . To be more specific, when the source device  2  is connected to a port of the external I/F  12 , the source device  2  that is connected supplies +5V power to the device controlling apparatus  1 . If +5V power is supplied to the port, the processing section  14  decides on “Yes” in step S 201 , the flow proceeds to step S 202 . If +5V power is not supplied, the processing section  14  returns to step S 201 , and waits until the source device  2  is connected. 
         [0031]    When the processing section  14  decides on “Yes” in step S 201 , the processing section  14  performs the CEC compliance/non-compliance check process (step S 202 ). The processing section  14  makes decisions in step S 202 , using a CEC command &lt;Report Physical Address&gt; sent immediately after a CEC-compliant device is connected. 
         [0032]    To be more specific, when the source device  2  is connected to a port of the external I/F  12 , the source device  2  acquires the physical address set in the port. Then, the connected source device  2  starts the processing for acquiring a logical address, and sends &lt;Report Physical Address&gt; for broadcasting the acquired physical address. Following the connection detection in step S 201 , if the processing section  14  can acquire &lt;Report Physical Address&gt; matching the physical address of the connected port, from the connected source device  2  within a certain period set in advance, the processing section  14  decides that the connected source device  2  is CEC-compliant. 
         [0033]    By contrast with this, if the processing section  14  cannot acquire &lt;Report Physical Address&gt; matching the physical address of the connected port, from the connected source device  2  within a certain period, the processing section  14  decides that the connected source device  2  is non-CEC-compliant. 
         [0034]    Based on the result of the above processings, the processing section  14  decides whether or not the connected source device  2  is CEC-compliant (step S 203 ). When deciding on “Yes,” the processing section  14  generates a message signal for notifying the user that the connected source device  2  is non-CEC-compliant, and sends the signal to the display  13 . When receiving the message signal, the display  13  displays its content M 1  for a certain period, as shown in  FIG. 3 , to notify the user that the connected source device  2  is non-CEC-compliant (step S 204 ). When step S 204  is finished, the processing section  14  finishes the processing of  FIG. 2 . 
         [0035]    Next, a specific example of the CEC compliance/non-compliance check process in step S 202 , will be explained with reference to  FIG. 4 .  FIG. 4  is a sequence chart showing exchange of CEC commands between the device controlling apparatus  1  and the source devices  2 A to  2 C in the CEC compliance/non-compliance check process. 
         [0036]    With the example of  FIG. 4 , the CEC compliance/non-compliance check process is performed with respect to the source devices  2 A to  2 C at substantially the same time. Here, assume that the source device  2 A alone is non-compliant. When the source devices  2 A to  2 C are connected to ports of the external I/F  12 , the source devices  2 A to  2 C each supply +5V power to the device controlling apparatus  1  (S 401 , S 403  and S 405  in the sequence). 
         [0037]    In the device controlling apparatus  1 , the processing section  14  starts the timer (not shown) of each port at the time +5V power from each of the source devices  2 A to  2 C is detected (S 402 , S 404  and S 406  in the sequence), and starts measuring predetermined periods T A , T B  and T C . When connection is established with the HDMI after +5V power is supplied, the CEC-compliant devices of the source device  2 A to  2 C send &lt;Report Physical Addresses&gt;, to the device controlling apparatus  1  (S 407  and S 409  in the sequence). As is clear from above, the source devices  2 B and  2 C are CEC-compliant, and, in the example of  FIG. 4 , send &lt;Report Physical Addresses&gt;. 
         [0038]    If &lt;Report Physical Addresses&gt; are received before the predetermined periods T A , T B  and T C  expire, the processing section  14  stops the measurement by the timers of the corresponding ports, and recognizes that the CEC-compliant devices are connected to the corresponding ports. 
         [0039]    By contrast with this, if &lt;Report Physical Addresses&gt; cannot be received before the predetermined periods T A , T B  and T C  expire, the processing section  14  recognizes that the non-CEC-compliant device is connected to the corresponding port. 
         [0040]    This concludes the CEC compliance/non-compliance check process. With the example of  FIG. 4 , the source device  2 A is non-CEC-compliant and does not send &lt;Report Physical Address&gt; within the predetermined period T A , and therefore the processing section  14  decides that the source device  2 A is non-CEC-compliant at the time the predetermined time T A  passes. 
         [0041]    Further, the CEC compliance/non-compliance check process is performed per port of the external I/F  12 . With the example of  FIG. 4 , although the CEC compliance/non-compliance check process is performed with respect to all source devices  2 A to  2 C at substantially the same time, there are cases where the CEC compliance/non-compliance check process is performed separately with respect to the source devices  2 A to  2 C. 
         [0042]    When the processing of  FIG. 2  explained above is finished, the user operates the operator  3  such that the processing section  14  sets up the external I/F  12  to output video signals from at least one source device  2 , to the display  13 . By this means, the display  13  receives the video signal from the set source device  2  through the external I/F  12 , and displays an image according to the received video signal. 
         [0043]    The processing for remotely controlling the source device  2  that is outputting a video signal (hereinafter, referred to as “target source device”) by the operator  3 , will be explained with reference to  FIG. 5 .  FIG. 5  is a flowchart showing the processing in the device controlling apparatus  1  after the operator  3  is operated. In  FIG. 5 , the processing section  14  decides whether or not the operator  3  has been operated (step S 501 ). To be more specific, if an operation code has not been received from the receiver  11 , the processing section  14  decides on “No” in step S 501 , returns to step S 501  and waits until the operation code is received. 
         [0044]    By contrast with this, if the operation code has been received from the receiver  11 , the processing section  14  decides on “Yes” in step S 501 . After making decisions as described above, the processing section  14  sends the CEC command &lt;User Control Pressed&gt; matching the operation code, to the target source device  2  through the external I/F  12 . Here, &lt;User Control Pressed&gt; is used to forward from the device controlling apparatus  1  of the sink device to the target source device  2 , the operation code sent from the operator  3 . 
         [0045]    According to the HDMI standard, if processing of the received CEC command is not executable, the target source device  2  returns the command &lt;Feature Abort&gt; to the device controlling apparatus  1 . The parameters of &lt;Feature Abort&gt; include [Feature Opcode], and, if &lt;User Control Pressed&gt; is not supported, Opcode of &lt;User Control Pressed&gt; is set as the value of [Feature Opcode]. Here, &lt;Feature Abort&gt; is used as a response to show whether the target source device  2  supports or cannot execute the requested CEC command at the moment. 
         [0046]    The processing section  14  receives &lt;Feature Abort&gt; through the external I/F  12 , and can confirm whether or not the target source device  2  supports &lt;User Control Pressed&gt;, based on information of &lt;Feature Abort&gt;. Using the processing of this &lt;Feature Abort&gt;, the processing section  14  performs the process of checking whether or not the target source device  2  complies with CEC remote controller pass-through control (step S 502 ). Based on the result of this check process, the processing section  14  decides whether or not the target source device  2  complies with CEC remote controller pass-through control (step S 503 ). 
         [0047]    For more detailed explanation of processings in steps S 502  and  503 , the processing section  14  counts the number of times &lt;Feature Abort&gt; is received, in response to &lt;User Control Pressed&gt; sent to the target source device  2 . The processing section  14  decides that the target source device  2  having received &lt;Feature Abort&gt; a predetermined number of times, as the device that does not comply with CEC remote controller pass-through control, that is, decides on “Yes” in step S 503 . 
         [0048]    When deciding on “No” in step S 503 , the processing section  14  returns to step S 501  and waits until the remote controller is operated again. By contrast with this, when deciding on “Yes” in step S 503 , first, the processing section  14  stops transmitting &lt;User Control Pressed&gt; to this target source device  2  that does not comply with CEC remote controller pass-through control, in response to subsequent operation codes. 
         [0049]    Following step S 504 , the processing section  14  generates a message signal for notifying the user that the target source device  2  is non-CEC-compliant, and sends the signal to the display  13 . When receiving the message signal, the display  13  shows its content M 1  for a certain period, as shown in  FIG. 3 , and notifies the user that the target source device  2  is non-CEC-compliant (step S 505 ). By this means, it is possible to remind of the user not to repeat operating the operator  3  in the same way. Further, in this case, the user operates the source device  2  or its attachment of a remote controller. 
         [0050]    Further, although not shown in  FIG. 5 , when the external I/F  12  and the target source device  2  are disconnected, the processing of  FIG. 5  is finished then. 
         [0051]    Next, a specific example of the process of checking CEC remote controller pass-through control compliance/non-compliance in step S 502 , will be explained with reference to  FIG. 6  and  FIG. 7 .  FIG. 6  and  FIG. 7  show the first half and the second half of a sequence chart of exchange of CEC commands between the device controlling apparatus  1  and the target source device  2  in the CEC remote controller pass-through control compliance/non-compliance check process. 
         [0052]    Further,  FIG. 6  and  FIG. 7  show cases where the target source device  2  is the source device  2 B. Furthermore, although, in  FIG. 6  and  FIG. 7 , the remote controller is illustrated to be operated a plurality of times in the CEC remote controller pass-through control compliance/non-compliance check process for ease of explanation, the actual processing undergoes the processing of step S 502  every time the remote controller is operated, and moves onto the processing of step S 501  to wait for the remote controller to be operated. 
         [0053]    First, in  FIG. 6 , when receiving an operation code from the operator  3  through the receiver  11  (S 601  in the sequence), the processing section  14  converts the received operation code into a CEC command, and sends &lt;User Control Pressed&gt; to the target source device  2 B through the external I/F  12  (S 602  in the sequence). 
         [0054]    The processing section  14  has a counter (not shown) for the process of checking whether or not the target source device  2 B complies with CEC remote controller pass-through control, and this value on the counter is incremented (S 604  in the sequence) every time &lt;Feature Abort&gt; is received from the target source device  2 B in response to &lt;User Control Pressed&gt; (S 603  in the sequence). 
         [0055]    By contrast with this, if &lt;Feature Abort&gt; is not received in response to &lt;User Control Pressed&gt;, the counter value is reset (S 611  in the sequence of  FIG. 7 ). 
         [0056]    These series of operations are repeated every time an operation code is received (S 605  in the sequence of  FIG. 6  to S 623  in the sequence of  FIG. 7 ). 
         [0057]    When the counter value exceeds the value that is set in advance (hereinafter, referred to as “reference value”), the processing section  14  decides that the target source device  2 B does not comply with CEC remote controller pass-through control (S 624  in the sequence). Further, with the example of  FIG. 7 , the reference value is set to C B =3. 
         [0058]    In the parameters of &lt;User Control Pressed&gt;, one [UI Command] is prepared for one operation code from the operator  3 . Although the reference value of the counter value is not set per operation code type with the examples of  FIG. 6  and  FIG. 7 , a method of preparing a counter per operation code type (per parameter of [UI Command]) and performing the CEC remote control pass-through control compliance/non-compliance check process (step S 502 ) per operation code type, is possible. 
         [0059]    In the above-described case where the source device  2  is controlled by the CEC commands, the device controlling apparatus  1  has the functions for checking the situation of responses from the source device  2  and deciding whether or the source device  2  is CEC compliant and does not execute CEC commands. When the source device  2  that cannot be controlled by the CEC commands is found thanks to this function, it is possible to notify the user that the source device  2  cannot be controlled by the CEC commands, and furthermore stop transmitting the CEC commands to the source device  2  to prevent the CEC commands from being transmitted unnecessarily, and improve the communication efficiency of CEC commands. 
         [0060]    Further, although, with the above explanation, the device controlling apparatus  1  receives an operation code from a remote controller which is illustrated as the operator  3 , it is equally possible to receive operation codes from a touch panel or keyboard mounted on the device controlling apparatus  1 . 
         [0061]    Furthermore, although, with the above explanation, the three source devices  2  are connected to the device controlling apparatus  1 , the number of source devices  2  to connect may be other than three. 
         [0062]    Still further, with the above explanation, if the CEC command &lt;Report Physical Address&gt; is not received in a certain period in the CEC compliance/non-compliance check process (step S 202  of  FIG. 2 ), the processing section  14  decides that the source device  2  is non-CEC-compliant. However, the present invention is not limited to this, and, if the CEC command &lt;Report Physical Address&gt; is not received in a certain period, the processing section  14  may transmit the CEC command &lt;Give Physical Address&gt; at least one more time to the source device  2  to check again whether or not the source device  2  complies with CEC. &lt;Give Physical Address&gt; is used to return the physical address of the source device  2 . Further, the CEC command for performing a check again is not limited to &lt;Give Physical Address&gt;, and may be a CEC command that is defined according to the HDMI standard and that makes responses mandatory. 
         [0063]    Further, with the above explanation, when the processing section  14  decides that the source device  2  does not comply with CEC remote controller pass-through control, the processing of  FIG. 5  is finished. However, the present invention is not limited to this, and, even if the source device  2  complies with CEC remote controller pass-through control, cases may be assumed depending on the time decisions are made in the processing section  14 , where &lt;Feature Abort&gt; is returned in response to &lt;User Control Pressed&gt; due to some factors. Assuming these cases, a method of finishing the processing of step S 505  and then returning processing to step S 501  after a certain period, may be adopted as shown in  FIG. 8 . 
         [0064]    Further, with the above explanation, the counter is provided to count the number of times &lt;Feature Abort&gt; is received in the CEC remote controller pass-through control compliance/non-compliance check process (step S 502  in  FIG. 5 ). However, the present invention is not limited to this, and each content of [Abort Reason] included as a parameter of &lt;Feature Abort&gt; may be counted. In addition, counters for the process of checking the CEC remote controller pass-through control compliance/non-compliance, may count the number of times ACK bit is not detected in response to &lt;User Control Pressed&gt;. 
         [0065]    Further, with the above explanation, when the source device  2  either does not comply with CEC or does not comply with CEC remote controller pass-through control, the message M 1  shown in  FIG. 3  is displayed on the display  13  as a method of providing notices to users. However, the present invention is not limited to this, and messages may vary between the non-CEC-compliant device and the device that does not comply with CEC remote controller pass-through control, or different display methods may be employed. 
         [0066]    Further, with the above explanation, the message M 1  shown in  FIG. 3  is displayed for a certain period after the CEC compliance/non-compliance check process (step S 202  of  FIG. 2 ) or the CEC remote controller pass-through control compliance/non-compliance check process (step S 502  of  FIG. 5 ). However, the present invention is not limited to this, and, after the message M 1  is displayed once, the message M 1  may be immediately displayed for a certain period every time the operator  3  receives the same operation. Further, the message M 1  may be displayed in, for example, the corner of the screen of the display  13  as shown in  FIG. 9  so as not to prevent images from being displayed. 
         [0067]    Furthermore, although, with the above explanation, notices to the user are provided by displaying the message M 1  on the display  13 , it is equally possible to provide notices to the user by a buzzer sound, speech guidance and so on. 
         [0068]    The disclosure of Japanese Patent Application No. 2008-126770, filed on May 14, 2008, including the specification, drawings and abstract, is incorporated herein by reference in its entirety. 
       INDUSTRIAL APPLICABILITY 
       [0069]    The device controlling apparatus according to the present invention provides an advantage of improving the communication efficiency of CEC commands, and is useful in, for example, display apparatuses that can serve as sink apparatuses. 
       REFERENCE SIGNS LIST 
       [0070]      1 . DEVICE CONTROLLING APPARATUS (SINK DEVICE) 
         [0071]      11  RECEIVER 
         [0072]      12  EXTERNAL I/F 
         [0073]      13  DISPLAY 
         [0074]      14  PROCESSING SECTION 
         [0075]      2  SOURCE DEVICE 
         [0076]      3  OPERATOR (REMOTE CONTROLLER)