Patent Publication Number: US-2012042352-A1

Title: Set top box and auto standby method thereof

Description:
BACKGROUND 
     1. Technical Field 
     The present disclosure relates to devices that process audio/video signals, and more particularly to a set top box and an auto standby method used in the set top box. 
     2. Description of Related Art 
     Set top boxes are a common way to control cable and satellite TV reception. Typically, set-top boxes can be manually put into a standby mode using a button on the box or on a remote control. However, manual operation of placing the set-top boxes in the standby mode makes it easy for users to forget, which results in wasted energy when the set-top box is not needed. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The details of the disclosure, both as to its structure and operation, can best be understood by referring to the accompanying drawings, in which like reference numbers and designations refer to like elements. 
         FIG. 1  is a schematic diagram illustrating one embodiment of an application environment of a set top box in accordance with an exemplary embodiment of the present disclosure. 
         FIG. 2  is a block diagram showing one embodiment of functional modules of the set top box of  FIG. 1 . 
         FIG. 3  is a flowchart of one embodiment of an auto standby method used in the set top box of  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  is a schematic diagram illustrating one embodiment of an application environment of a set top box  100  in accordance with an exemplary embodiment of the present disclosure. The set top box  100  communicates with a television (TV)  200  when in use. 
     The set top box  100  includes a memory  110 , one or more central processing units (CPUs)  120  electrically connected to the memory  110 , and a High-Definition Multimedia Interface (HDMI)  130  embedded in the set top box  100  and connected to the memory  110 . The TV  200  is coupled to the set top box  100  via an HDMI cable (not shown) plugged into the HDMI  130 . 
     It is understood that the memory  110  may include volatile memory and may also include non-volatile memory, such as one or more magnetic disk storage devices, flash memory devices, or other non-volatile solid state memory devices. In the embodiment, the memory  110  includes non-volatile memory. The one or more CPUs  120  run various software programs and/or sets of instructions stored in the memory  110  to perform various functions for the set top box  100  and to process data. The HDMI  130  is connected to the TV  200  by an I 2 C Bus to transmit the data therein. 
       FIG. 2  is a block diagram showing the functional modules of the set top box  100  of  FIG. 1 . In the present embodiment, the set top box  100  includes a transmitting module  10 , a reading module  20 , a determining module  30 , and a controlling module  40  stored in the memory  110 . Note the modules  10 - 40  may comprise computerized code in the form of one or more programs that are stored in the memory  110 . The computerized code includes instructions that are executed by the one or more CPUs  120  to provide corresponding functions for modules  10 - 40 . 
     The transmitting module  10  periodically transmits a connection request to the TV  200  via the HDMI  130  and the HDMI cable, to request a number of response signals from the TV  200 . In the present embodiment, the connection request may be transmitted at a predetermined time interval. Generally, when the TV  200  is in a working state, the TV  200  may feedback a number of response signals to the set top box  100 . In the present embodiment, the response signals may be extended display identification data (EDID), which are standard Video Electronics Standards Association (VESA) data and includes strings of parameters of the TV  200 , such as vendor information, maximum image size, color settings, manufacturers pre-setting, frequency range, name, and serial number, for example. Moreover, according to the I 2 C protocol, the EDID includes an acknowledgement (ACK) code when the TV  200  is in the working state. The EDID may be formatted to include a number of characters by placing the ACK code at a predetermined bit position in the EDID. In the present embodiment, when the TV  200  is in a working state, the predetermined bit position of the ACK code indicates a “1”. However, when the TV  200  is turned off or in a sleeping/standby state, the TV  200  may not respond to the connection request, and the predetermined bit position of the ACK code indicates a “0”. 
     The reading module  20  reads the response signals when the TV  200  is in a working state. When the reading module  20  does not receive the response signals in a predetermined time, that is, the TV  200  is turned off or in sleeping/standby state, the reading module  20  outputs an idle signal to the determining module  30 . In the present embodiment, the reading module  20  includes a time calculating unit  21  that continuously calculates an idle time period during the time the reading module  20  does not receive the response signals. Furthermore, when the idle time period is equal to the predetermined time, the reading module  20  outputs the idle signal to the determining module  30 . 
     The determining module  30  determines the state of the TV  200  according to the receipt of the response signals or the idle signal. In the present embodiment, the determining module  30  determines that the TV  200  is in working state when the reading module  20  receives the response signals, and determines that the TV  200  is turned off or in a sleeping/standby state when the reading module  20  receives the idle signal. In detail, the determining module  30  determines whether the ACK code is “1”, to determine the state of the TV  200 . That is, if the ACK code is “1”, the determining module  30  determines the TV  200  is in working state, if the ACK code is “0”, the determining module  30  determines the TV  200  is turned off or in a sleeping/standby state. Furthermore, the determining module  30  outputs a starting signal to the controlling module  40  after determining the TV  200  is in working state, otherwise the determining module  30  outputs a standby signal to the controlling module  40 . 
     The controlling module  40  controls the set top box  100  to remain in the working state if the starting signal is received, and places the set top box  100  in sleeping/standby state if the standby signal is received. As such, the set top box  100  can automatically go on standby. Note that the set top box  100  may be controlled by a software controller to switch between a working mode and a standby mode. The software controller may be, for example, a software or a control circuit, according to the starting signal or the standby signal input to the software controller. Specifically, when the set top box  100  is in the standby mode, the other functional modules (e.g. a video/audio processing module) except for the transmitting module  10 , the reading module  20 , the determining module  30 , and the controlling module  40  of the set top box  100  are placed in the sleeping/standby state. As such, in spite of the set top box  100  being in the standby mode, the memory  110  and the CPU  120  can still work while the other functional modules of the set top box  100  are on standby. 
     Furthermore, the memory  110  stored with the transmitting module  10 , the reading module  20 , the determining module  30 , and the controlling module  40  can be integrated in the set top box  100 , or independent from the set top box  100  and electronically connected to the set top box  100 . 
       FIG. 3  is a flowchart of one embodiment of an auto standby method used in the set top box  100 . Depending on the embodiment, additional steps may be added, others deleted, and the ordering of the steps may be changed. 
     In step S 301 , the set top box  100  periodically transmits a connection request to the TV  200 , to request a number of response signals from the TV  200 . In the present embodiment, the connection request may be transmitted at a predetermined time interval. Typically, when the TV  200  is in the working state, the TV  200  may feedback a number of response signals to the set top box  100 . However, when the TV  200  is turned off or in sleeping/standby state, the TV  200  may not respond. 
     In step S 303 , the set top box  100  reads the response signals when the TV  200  is in the working state. When the reading module  20  does not receive the response signals in a predetermined time, the set top box  100  outputs an idle signal to the determining module  30 . As mentioned previously, the time calculating unit  21  continuously calculates an idle time period during the time the set top box  100  does not receive the response signals. Also, when the idle time period is equal to the predetermined time, the set top box  100  outputs the idle signal. 
     In step S 305 , the set top box  100  determines the state of the TV  200  according to the response signals or the idle signal. In the present embodiment, the set top box  100  determines that the TV  200  is in the working state when receives the response signals, and determines that the TV  200  is turned off or in the sleeping/standby state when receives the idle signal. 
     In step S 307 , the set top box  100  outputs a starting signal or a standby signal according to state of the TV  200 . In the present embodiment, the set top box  100  outputs a starting signal after determining the TV  200  is in the working state, or the set top box  100  outputs a standby signal after determining the TV  200  is turned off or in the sleeping/standby state. 
     In step S 309 , the set top box  100  controls specific functional modules of the set top box  100  to remain in a working state according to the starting signal, or places the special functional modules in sleeping/standby state according to the standby signal. Thus, state of the set top box  100  can be set according to receipt of the response signal or the idle signal. Specifically, according to the present embodiment, when the set top box  100  is in the standby mode, the other functional modules (e.g. a video/audio processing module) except for the transmitting module  10 , the reading module  20 , the determining module  30 , and the controlling module  40  of the set top box  100  are placed in the sleeping/standby state. As such, in spite of the set top box  100  being in the standby mode, the memory  110  and the CPU  120  can still work while the other functional modules of the set top box  100  are on standby. 
     While various exemplary and preferred embodiments have been described, it is to be understood that the disclosure is not limited thereto. To the contrary, various modifications and similar arrangements (as would be apparent to those skilled in the art) are intended to also be covered. Therefore, the scope of the appended claims should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements.