Abstract:
A method and a digital device for controlling a connection between a plurality of nodes through an interface are discussed. The method according to an embodiment includes receiving control information including identification information of a destination node and a connection command. During a connection state according to the connection command, the connection between the plurality of nodes is established and the plurality of nodes maintain the connection state until a disconnection command is detected. The method further includes transmitting, according to the control information, response information including identification information of a source node.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This Application is a Continuation of co-pending U.S. patent application Ser. No. 14/600,435 filed on Jan. 20, 2015, which is a Continuation of U.S. patent application Ser. No. 14/282,776 filed on May 20, 2014 (now U.S. Pat. No. 8,976,755 issued on Mar. 10, 2015), which is a Continuation of U.S. patent application Ser. No. 13/943,967 filed on Jul. 17, 2013 (now U.S. Pat. No. 8,817,812 issued on Aug. 26, 2014), which is a Continuation of U.S. patent application Ser. No. 13/034,981 filed on Feb. 25, 2011 (now U.S. Pat. No. 8,594,124 issued on Nov. 26, 2013), which is a Continuation of U.S. patent application Ser. No. 11/833,540 filed on Aug. 3, 2007 (now U.S. Pat. No. 7,899,021 issued on Mar. 1, 2011), which is a Continuation of U.S. patent application Ser. No. 11/451,444 filed on Jun. 13, 2006 (now U.S. Pat. No. 7,289,482 issued on Oct. 30, 2007), which is a Continuation of U.S. patent application Ser. No. 09/644,301 filed on Aug. 23, 2000 (now U.S. Pat. No. 7,068,674 issued on Jun. 27, 2006), which claims the benefit under 35 U.S.C. §119(a) to Korean Patent Application No. 10-1999-35030 filed on Aug. 23, 1999, all of which are hereby expressly incorporated by reference into the present application. 
    
    
     BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The present invention relates generally to a digital interface, and more particularly to a method of controlling connection between nodes in a digital interface. 
     Discussion of the Related Art 
       FIG. 1  illustrates a connection state of a conventional 1394 system connected between nodes. Referring to  FIG. 1 , the conventional digital interface includes first and second input plug control registers  21  and  22  for inputting/outputting connection information between nodes connected to a 1394 serial bus  10  in accordance with control signals of an application node (not illustrated), a first audio/video node  20  comprising a first input master plug register  23 , a third input plug control register  31  for inputting/outputting connection information between nodes connected to the 1394 serial bus  10  in accordance with control signals of the application node, a second audio/video node  30  comprising a second input master plug register  32 , a fourth input plug control register  41  for inputting/outputting connection information between nodes connected to the 1394 serial bus  10  in accordance with control signals of the application node, a third video/audio node  40  comprising a third input master plug register  42 , fifth and sixth plug control registers  51  and  52  for inputting/outputting connection information between nodes connected to the 1394 serial bus  10  in accordance with control signals of the application node, a fourth audio/video node  50  comprising a fourth input master plug register  53 , an output plug control register  61  for inputting/outputting connection information between nodes connected to the 1394 serial bus  10  in accordance with control signals of the application node, and a fifth audio/video node  60  comprising an output master plug register  62 . 
     The method of controlling connection between nodes for the conventional digital interface as constructed above will be explained in detail with reference to accompanying drawings. 
     The application node is allocated with a channel for transmitting isochronous data from the fifth audio/video node  60  to the first audio/video node  20  through a point-to-point connection or broadcast connection, and writes in the same format the output plug control register in the fifth audio/video node  60  and the input plug control register in the first audio/video node  20  in the output plug control register  61  and the second input plug control register  22 . 
     Thereafter, the application node writes “1” in an on-line bit of the output plug control register  61  in the fifth audio/video node  60  and an on-line bit of the second input plug control register  22  to transmit the isochronous data. 
     Also, the application node writes in the same format the output plug control register in a point-to-point connection counter or a broadcast connection counter of the output plug control register  61  in the fifth audio/video node  60 . 
     Then, the isochronous data is transmitted from the fifth audio/video node  60  to the first audio/video node  20  through the channel. 
     Thus, transmission of the isochronous data from the fifth audio/video node  60  to the second and fourth audio/video nodes  30  and  40  is performed through the above-described process. 
     According to the conventional method of controlling connection between nodes in a digital interface, however, since no command for connection the nodes to the digital interface is provided, the transmission/reception, reproduction and control of a data stream of a predetermined program cannot be smoothly performed. 
     SUMMARY OF THE INVENTION 
     Accordingly, the present invention is directed to a method of controlling connection between nodes in a digital interface that substantially obviates one or more of the problems due to limitations and disadvantages of the related art. 
     An object of the present invention is to provide a method of controlling connection between nodes in a digital interface whereby a first node that is a master node determines a second node as a master, and a point-to-point connection or a broadcast connection to another third node is controlled through the second node. 
     Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims thereof as well as the appended drawings. 
     To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described, the method of controlling connection between nodes in a digital interface comprises the steps of a first node that is a master having a display device determining a second node to be a master in accordance with a user selection and transmitting a connection command of a predetermined format for transmitting a data stream, and the second node determined as the master in accordance with the transmitted connection command of the predetermined format being allocated with a channel and a bandwidth from an isochronous resource manager (IRM), performing a point-to-point connection between the second node and the first node, and transmitting the data stream. 
     The connection command of the predetermined format may be composed of a subfunction region representing whether the connection is the point-to-point connection or a broadcast connection, a connection region representing whether to make or cut off the connection, a source node identification (ID) region representing a source node ID of the node which transmits the data stream, and a destination node ID region representing a destination node ID of the node which receives the data stream. 
     The subfunction region may be set to the broadcast connection from the second node to the first node or another node to enable the transmission of the data stream. 
     At the data stream transmitting step, the second node may transmit a response of a predetermined format which corresponds to the connection command of the predetermined format to the first node. 
     The format of the response may be the same as the format of the connection command. 
     The format of the response may further include a bandwidth region representing a bandwidth allocated from the source node, a source channel number region representing a source channel number allocated from the source node, an output plug control register number region representing an output plug control register (PCR) number of the source node, a destination channel number region representing a destination channel number of the destination node for receiving the data stream, and an input PCR number region representing an input PCR number of the destination node. 
     According to another aspect of the present invention, the first node that is the master having the display device determines the second node to be the master in accordance with the user selection to perform the point-to-point connection to a third node, and transmits the connection command of the predetermined format for transmitting the data stream. The second node is allocated with the channel and the bandwidth from the isochronous resource manager (IRM), and then performs the point-to-point connection between the second node itself and the third node to enable transmission of the data stream. 
     According to another aspect of the invention, the first node having the display device determines the second node to be the master in accordance with the user selection, and transmits the connection command of the predetermined format for transmitting the data stream to a third node, and the second node is allocated with the channel and the bandwidth from the IRM, and then performs the point-to-point connection between the second node itself and to the third node to enable transmission of the data stream. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention: 
       In the drawings: 
         FIG. 1  is a view illustrating a connection state of a conventional 1394 system connected between nodes. 
         FIG. 2  is a block diagram illustrating the construction of a system to which the method of controlling connection between nodes in a digital interface according to an embodiment of the present invention is applied. 
         FIGS. 3A and 3B  are views illustrating a connection command form according to the method of controlling connection between nodes in a digital interface according to an embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Reference will now be made in detail to the method of controlling connection between nodes in a digital interface according to a preferred embodiment of the present invention, examples of which are illustrated in the accompanying drawings. 
       FIG. 2  is a block diagram illustrating the construction of a system to which the method of controlling connection between nodes in a digital interface according to an embodiment of the present invention is applied. The system comprises a digital television (DTV)  101 , a set-top box (STB)  102 , and a digital video disk (DVD) player  103 , and a disk  104 . 
       FIGS. 3A and 3B  are views illustrating a connection command form according to the method of controlling connection between nodes in a digital interface according to an embodiment of the present invention. As shown in  FIG. 3A , the connection command is composed of a subfunction region representing whether the connection is a point-to-point connection or a broadcast connection, a connection region representing whether to make or cut off the connection, a source node identification (ID) region representing a source node ID of the node which transmits a data stream, and a destination node ID region representing a destination node ID of the node which receives the data stream, a bandwidth region representing a bandwidth allocated from the source node, a source channel number region representing a source channel number allocated from the source node, an output plug control register number region representing an output plug control register (PCR) number of the source node, a destination channel number region representing a destination channel number of the destination node for receiving the data stream, and an input PCR number region representing an input PCR number of the destination node. The subfunction region in  FIG. 3A  is illustrated in detail in  FIG. 3B . 
     The method of controlling connection between nodes in a digital interface as constructed above will be explained in detail with reference to the accompanying drawings. 
     First, if a user selects the DTV  101  or the STB  102  which are displayed on a screen in order to view a specified program received in the STB  102  through an IEEE 1394 cable as shown in  FIG. 2 , the DTV  101  transmits the connection command of a predetermined format as shown in  FIGS. 3A and 3B  to the STB  102  with the STB  102  determined as a master to transmit the data stream. 
     Specifically, before transmitting the connection command to the STB  102 , the DTV  101  writes “0x01” in the subfunction region of the connection command as shown in  FIGS. 3A and 3B  to record the point-to-point connection, “0x00” in the connection region to record making of the connection, the node ID of the STB  102  in the source node ID region, and its own ID in the destination node ID region, respectively. 
     The node IDs of the nodes displayed on the screen are connected to the IEEE 1394 cable, and are stored in the DTV  101  when the power is turned on or the bus is reset. 
     Then, the STB  102  transmits a response corresponding to the connection command to the DTV  101  in accordance with the connection command transmitted from the DTV  101 . 
     Here, the STB  102  may transmit a command identical to the connection command as the response. 
     Also, before transmitting the connection command to the DTV  101  as the response, the STB  102  may additionally write the bandwidth allocated from the isochronous resource manager in the bandwidth region, the channel number allocated from the isochronous resource manager in the source channel number region, its own output plug control register (PCR) number in the output PCR number region, the allocated channel number in the destination channel number region, and the input PCR number of the DTV  101  in the input PCR number region, respectively. 
     Thereafter, the STB  102  is allocated with the channel and bandwidth from the isochronous resource manager (not illustrated), sets its own output plug control register and the input plug control register of the DTV  101  for the point-to-point connection as shown in  FIG. 1 , and then transmits the data stream of the program to the DTV  101  to display the data stream on the screen. 
     Here, the DTV  101  writes “0x10”, which means the broadcast connection, in the subfunction region of the connection command, and transmits the connection command, so that the data stream of the program can be broadcast from the STB  102  to not only the DTV  101  itself but also other nodes connected to the IEEE 1394 cable. 
     If the display is completed, the DIV  101  transmits the connection command to the STB  102  after writing “×01” in the subfunction region of the connection command to record the point-to-point connection, “0x10” in the connection region to record cut-off of the connection, the node ID of the STB  102  in the source node ID region, and its own node ID in the destination node ID region, so that the point-to-point connection or the broadcast connection can be released. 
     Also, if a user selects the DVD player  103  among the DTV  101 , STB  102 , and DVD player  103  displayed on the screen as shown in  FIG. 2  to store the data stream of the program being viewed in the disk  104 , the DTV  101  transmits the connection command of a predetermined format as shown in  FIGS. 3A and 3B  to the DVD player  103  with the DVD player  103  determined as a master to store the data stream. 
     Specifically, before transmitting the connection command to the DVD player  103 , the DTV  101  writes “0x01” in the subfunction region of the connection command as shown in  FIGS. 3A and 3B  to record the point-to-point connection, “0x00” in the connection region to record the making of the connection, the node ID of the DTV  101  in the source node ID region, and the node ID of the DVD player  103  in the destination node ID region, respectively. 
     The node IDs of the nodes displayed on the screen are connected to the IEEE 1394 cable, and stored in the DTV  101  when the power is turned on or the bus is reset. 
     Then, the DVD player  103  transmits a response corresponding to the connection command to the DIV  101  in accordance with the connection command transmitted from the DTV  101 . 
     Here, the DVD player  103  may transmit a command identical to the connection command as the response. 
     Also, before transmitting the connection command to the DTV  101  as the response, the DVD player  103  may additionally write the bandwidth allocated from the isochronous resource manager in the bandwidth region, the channel number allocated from the isochronous resource manager in the source channel number region, the output plug control register (PCR) number of the DTV  101  in the output PCR number region, the channel number allocated from the isochronous resource manager in the destination channel number region, and its own input PCR number in the input PCR number region, respectively. 
     Thereafter, the DVD player  103  is allocated with the channel and bandwidth from the isochronous resource manager (not illustrated), sets its own input plug control register and the output plug control register of the DTV  101  for the point-to-point connection as shown in  FIG. 1 , and then receives the data stream outputted from the DTV  101  to store the data stream in the disk  104 . 
     Here, the DTV  101  writes “0x10”, which means the broadcast connection, in the subfunction region of the connection command, and transmits the connection command, so that the data stream of the program being viewed can be broadcast from itself to not only the DVD player  103  but also other nodes connected to the IEEE 1394 cable. 
     If the display is completed, the DTV  101  transmits the connection command to the DVD player  103  after writing “0x01” in the subfunction region of the connection command to record the point-to-point connection, “0x10” in the connection region to record cut-off of the connection, the node ID of the DTV  101  in the source node ID region, and the node ID of the DVD player  103  in the destination node ID region, so that the point-to-point connection or the broadcast connection can be released. 
     Also, if a user selects the STB  102  among the DTV  101 , STB  102 , and DVD player  103  displayed on the screen as shown in  FIG. 2  to store the data stream of the program being received from the STB  102  through the IEEE 1394 cable in the disk  104 , the DTV  101  transmits the connection command of a predetermined format as shown in  FIGS. 3A and 3B  to the STB  102  with the STB  102  determined as a master to store the data stream. 
     Specifically, before transmitting the connection command to the STB  102 , the DIV  101  writes “0x01” in the subfunction region of the connection command as shown in  FIGS. 3A and 3B  to record the point-to-point connection, “0x00” in the connection region to record the making of the connection, the node ID of the STB  102  in the source node ID region, and the node ID of the DVD player  103  in the destination node ID region, respectively. 
     The node IDs of the nodes displayed on the screen are connected to the IEEE 1394 cable, and stored in the DTV  101  when the power is turned on or the bus is reset. 
     Then, the STB  102  transmits a response corresponding to the connection command to the DTV  101  in accordance with the connection command transmitted from the DTV  101 . 
     Here, the STB  102  may transmit a command identical to the connection command as the response. 
     Also, before transmitting the connection command to the DTV  101  as the response, the STB  102  may additionally write the bandwidth allocated from the isochronous resource manager in the bandwidth region, the channel number allocated from the isochronous resource manager in the source channel number region, its own output plug control register (PCR) number in the output PCR number region, the allocated channel number in the destination channel number region, and the input PCR number of the DVD player  103  in the input PCR number region, respectively. 
     Thereafter, the STB  102  is allocated with the channel and bandwidth from the isochronous resource manager (not illustrated), sets its own output plug control register and the input plug control register of the DVD player  103  for the point-to-point connection as shown in  FIG. 1 , and then transmits the received data stream to the DVD player  103 . 
     Then, the DVD player  103  stores in the disk  104  the data stream of the program transmitted from the STB  102  through the point-to-point connection. 
     Here, the DTV  101  writes “0x10”, which means the broadcast connection, in the subfunction region of the connection command, and transmits the connection command, so that the data stream of the program received from the STB  102  is not only stored in the disk  104  through the DVD player  103  but also broadcast to other nodes connected to the IEEE 1394 cable. 
     If the display is completed, the DTV  101  transmits the connection command to the STB  102  after writing “0x01” in the subfunction region of the connection command to record the point-to-point connection, “0x10” in the connection region to record cut-off of the connection, the node ID of the STB  102  in the source node ID region, and the node ID of the DVD player  103  in the destination node ID region, so that the point-to-point connection or the broadcast connection can be released. 
     Meanwhile, if a user selects the DVD player  103  among the DTV  101 , STB  102 , and DVD player  103  displayed on the screen as shown in  FIG. 2  to reproduce through the DVD player  103  and view through the DTV  101  the data stream of the program stored in the disk  104 , the DTV  101  transmits the connection command of a predetermined format as shown in  FIGS. 3A and 3B  to the DVD player  103  with the DVD player  103  determined as a master to reproduce the data stream of the program stored in the disk  104  and transmit the data stream to the DTV  101  itself. 
     Specifically, before transmitting the connection command to the DVD player  103 , the DTV  101  writes “0x01” in the subfunction region of the connection command as shown in  FIGS. 3A and 3B  to record the point-to-point connection, “0x00” in the connection region to record the making of the connection, the node ID of the DVD player  103  in the source node ID region, and its own node ID in the destination node ID region, respectively. 
     The node IDs of the nodes displayed on the screen are connected to the IEEE 1394 cable, and stored in the DTV  101  when the power is turned on or the bus is reset. 
     Then, the DVD player  103  transmits a response corresponding to the connection command to the DTV  101  in accordance with the connection command transmitted from the DTV  101 . 
     Here, the DVD player  103  may transmit a command identical to the connection command as the response. 
     Also, before transmitting the connection command to the DTV  101  as the response, the DVD player  103  may additionally write the bandwidth allocated from the isochronous resource manager in the bandwidth region, the channel number allocated from the isochronous resource manager in the source channel number region, its own output plug control register (PCR) number in the output PCR number region, the allocated channel number in the destination channel number region, and the input PCR number of the DTV  101  in the input PCR number region, respectively. 
     Thereafter, the DVD player  103  is allocated with the channel and bandwidth from the isochronous resource manager, sets its own output plug control register and the input plug control register of the DTV  101  for the point-to-point connection as shown in  FIG. 1 , and then reproduces the data stream of the program stored in the disk  104  to transmit the reproduced data stream to the DTV  101 . 
     Then, the DTV  101  displays on the screen the data stream of the program transmitted from the DVD player  103  through the point-to-point connection. 
     Here, the DTV  101  writes “0x10”, which means the broadcast connection, in the subfunction region of the connection command, and transmits the connection command, so that the data stream of the program being reproduced and transmitted from the DVD player  103  can be not only displayed on the screen but also broadcast to other players connected to the IEEE 1394 cable. 
     If the display is completed, the DTV  101  transmits the connection command to the DVD player  103  after writing “0x01” in the subfunction region of the connection command to record the point-to-point connection, “0x10” in the connection region to record cut-off of the connection, the node ID of the DVD player  103  in the source node ID region, and its own node ID in the destination node ID region, so that the point-to-point connection or the broadcast connection can be released. 
     As described above, according to the method of controlling connection between nodes in a digital interface, one node among nodes connected to the digital interface, that is a master, determines another node to be the master, and controls a point-to-point connection or a broadcast connection among the nodes, so that the transmission/reception, reproduction, and control of the data stream of a certain program can be smoothly performed. 
     While the present invention has been described and illustrated herein with reference to the preferred embodiments thereof, it will be apparent to those skilled in the art that various modifications and variations can be made therein without departing from the spirit and scope of the invention. Thus, it is intended that the present invention covers the modifications and variations of this invention that come within the scope of the appended claims and their equivalents.