MXPA01000270A - Network connection recognizing method and network-connected terminal device - Google Patents

Abstract

When a plurality of apparatuses are connected to a specified network, and when an apparatus connected to the network is to be recognized in order to simplify a recognition work required as when bus-resetting the apparatus connected to the network, after identifying the object apparatus, specified data obtained from the identified object apparatus is compared with specified data previously collected and stored and, when they match, the apparatus is judged to be a previously-connected apparatus to use, as the apparatus data, the data on the apparatus collected when previously connected to thereby recognizing it.

Description

DESCRIPTION OF A METHOD FOR THE RECOGNITION OF A NETWORK CONNECTION AND TERMINAL DEVICE FOR THE CONNECTION OF NETWORK FIELD OF THE ART The present invention relates to a method for recognizing a suitable network connection for recognizing a device connected by a bus line, for example, the IEEE (The Institute of Electrical and Electronics Engineers) (scheme 1394, and a terminal device for network connection for which this method for network recognition has been applied.

BACKGROUND OF THE ART AV devices capable of transmitting information to each other through a network using a serial data bus of the IEEE 1394 scheme have been developed. In this network, an AV device connected to the network can be controlled using a default command (AV / C) Apply Transaction Instruction). In the following description, this instruction refers to an AV / C instruction. The details of the AV / C instruction will be described later. As with conventional AV devices connected via the bus line of the IEEE 1394 scheme, there are digital video camera devices and digital video tape recorders and playback devices, for example, a standard scheme called DV. In other words, two engraving and reproduction devices are prepared and connected by means of a bus line that conforms to the 1394 scheme of the IEEE. The digital video data is reproduced from a device that is transmitted by this bus line and recorded by the other device. In this way, by connecting AV devices via the bus line of the IEEE 1394 scheme, large data capacity such as real-time digital video data and video data editing or the like can be efficiently transmitted and conducted. The data that can be transmitted by means of the bus line of the IEEE 1394 scheme are not limited to the digital video data described above, but various types of other digital data can be transmitted. Various data managed by means of AV devices can be transmitted. In other words, a large number of devices (for example, 63 devices) can be connected to a network by means of the bus line of the 1394 scheme of the IEEE. Among a large number of devices, video data, audio data, and control data can be transmitted. For example, it becomes possible to connect an IRD (Integrated Receiver Decoder) that serves as a receiving device for receiving digital satellite transmission to a digital video tape recorder and playback device referred to as a DVCR (Digital Video Cassette Recorder) using a magnetic tape as a recording medium by means of the bus line of the IEEE 1394 scheme, and recorded video data received by the IRD, using the DVCR. In addition, it becomes possible to connect a digital audio disc recording and playback device using a magnetic optical disc called MD (Mini Disc) as a recording medium to the same bus line, and record the audio data received by the IRD, by using the audio disc recording and playback device (MD device). In the case where in addition to a large number of devices are connected to a network, a device for controlling transmission data within the network in the IEEE 1394 scheme provides all the devices in the network with individual nodes IDs, and controls the source transmission and receiving destination through the ID nodes. As a result, it is possible to transmit data een specific devices in the network. In addition to the measurement of the IDs of the nodes described above, the device for controlling transmission data in the network needs to discriminate the type of each of the connected devices and control the efficiency according to the discriminated type. For example, in the case of a device corresponding to an instruction such as the instruction described above AV / C, it is necessary to transmit to a predetermined instruction or as prescribed in the schema, transmit data concerning the function contained in each device, and collect the transmitted data. The work of arranging the ID node and discrimination of the type of device is carried out when the bus line included in the network is restored. The bus line is restored when there is an alteration in the devices connected to the bus line, also when a new network is formed. In the case where the configuration of the network is altered at any time, there is a possibility to reset the bus frequently. In the case where the number of devices connected to the bus line included in the network is large as described above, there is a problem that a heavy load is thrown towards the data collection work of all the devices and the time required for the process is also long. DECLARATION D3 THE INVENTION An object of the present invention is to simplify the discrimination work of a device at the moment of resetting the bus or the like, in the case where a network of the 1394 scheme of the IEEE or similar is formed. A fiinvention is a method for recognizing a network connection for the recognition of a device connected to a predetermined network, including: a recognition recognition device step of a device connected to the network; a step of acquiring predetermined data acquired from the recognition device; and a comparison step of comparing the predetermined data obtained from the recognition device with the predetermined data previously collected and stored, wherein when in the comparison step of the predetermined data obtained from the recognition device it has coincided with the predetermined data previously collected and stored, the data concerning a device corresponding to the stored predetermined data is used as data concerning the recognition device. Therefore, through the. comparison of predetermined data transmitted from the recognition device with the stored data, making a judgment of the coincidence of the device to be a previously connected device, and using data concerning the previously collected and stored device, it is unnecessary to collect data concerning the device from the device.

A second invention is the method for recognizing a network connection of the first invention, wherein the predetermined data is an identifier capable of identifying each device individually. By doing this, a device can be discriminated simply by using an identifier. A third invention is the method for recognizing a network connection of the first invention, including a collection step of data collection data concerning the device when the predetermined data obtained from the recognition device has not coincided with the predetermined data previously collected and stored. By doing this, the data collection step concerning the device is executed only for a device newly connected to the network. In addition, the time and process required for data collection can be reduced. A fourth invention is the method for recognizing a network connection of the third invention, wherein the data collection step includes: a step of sending a request instruction to send an instruction to request a unit type or a type of subunit pari the device; and a discrimination discrimination step of the unit type or subunit type of the device based on the response of the device. By doing this, it is certainly possible to know the type of unit or type of subunit implemented in the device. A fifth invention is the method for recognizing a network connection of the fourth invention, wherein the data collection step further includes: a step of sending a corresponding instruction type to send an instruction corresponding to the discriminated type; and a step to determine the type of device to determine the type of device based on the response obtained by the step of sending a corresponding type of instruction. By doing this, it becomes possible to discriminate the device connected to the network more undoubtedly by the step of sending the corresponding type of instruction and step to determine the type of device. A sixth invention is the method for the recognition of a network connection of the first invention, wherein the recognition step of recognition device of a device connected to the network is carried out when a bus line formed in the network is re-established. net. By doing this, it becomes possible to conduct the data collection of each device at the time of re-establishing the bus, for example, in the case where the network configuration is changed, with a reduced load in a short time. A seventh invention is the method for recognizing a network connection of the first invention, including the data erasing step of erasing the stored predetermined data when predetermined data previously collected and stored does not match any of the predetermined data obtained from the recognition device. By doing this, the storage of predetermined data of the concerned devices that have been disconnected from the network is erased. In addition, data that is not required for the control of devices in the network are efficiently erased. An eighth invention is the method for recognizing a network connection of the first invention, including the data erasing step of erasing data concerning a device corresponding to predetermined data stored when the predetermined data previously collected and stored does not match any of the predetermined data obtained from the recognition device. By doing this, the storage of the data concerning the devices that have been disconnected from the network is erased. In addition, data that is not required to control devices in the network is efficiently erased.

A ninth invention is a terminal device for the network connection connected to a predetermined network, the terminal device for the network connection includes: A storage section for storing data concerning a device connected through the network; and A control section that serves as a response to the recognition of a device connected via the network, to compare predetermined data transmitted from the device with data stored in the storage section, causing data concerning devices that do not coincide in the comparison that is transmitted, and causing data storage of the storage section to be discharged, when a device that does not match predetermined stored data in the storage section is recognized, therefore, data concerning the device is obtained. In this way it becomes possible to collect only the data concerning the connected devices again efficiently and simply. Once an invention is a terminal device for network connection connected to a predetermined network, the terminal device for network connection includes: The device for recognizing means for recognizing a device connected to the network; The acquisition data of means for obtaining predetermined data from the recognition device; and comparing means for comparing the predetermined data obtained from the recognition device with predetermined data previously collected and stored, wherein when in the comparison of means the predetermined data obtained from the recognition device coincides with the predetermined data previously collected and stored. , the data concerning a device corresponding to the stored predetermined data are used as data concerning the recognition device. Therefore, by comparing predetermined data transmitted from the recognition device with stored data, a judgment is made of the coincidence of the device that is going to be a previously connected device, and using data concerning the device previously collected and stored, It makes it unnecessary to collect data concerning the device of the device. In this way, the load required for the collection of data from the devices connected to the network can be reduced. In addition, a terminal device capable of shortening the time required for the process is obtained. An eleventh invention is the terminal device for the network connection of the tenth invention, wherein the predetermined data is an identifier capable of identifying each of the devices individually. By doing this, a device can be discriminated simply by using an identifier. A twelfth invention is the terminal device for the network connection of the tenth invention, which includes: the output instruction means for generating and outputting a first instruction to ask for a device connected via the network about a type of unit or type of subunit; and the means of discrimination to receive a response to the first instruction, and to discriminate a type of unit or a type of device suburban based on the response. By doing this, it is certainly possible to know the type of unit or type of subunit implemented in the connected device. A thirteenth invention is the terminal device for the network connection of the twelfth invention, including: the output instruction means for generating and outputting a second instruction corresponding to a unit type or a subunit type of the device; and the receiving means for receiving a response to the second instruction from the device. By doing so, it becomes possible to discriminate the device connected to the network more undoubtedly by the generation of the first instruction and the second instruction in the instruction output means. A fourteenth invention is the terminal device for the network connection of the tenth invention, wherein the means for recognition for the device lead the process to recognize a device connected to the network when the means for recognition of the device have detected the reestablishment of a Bus line formed in the network. By doing this, it becomes possible to conduct the data collection of each of the connected devices at the time of re-establishing the bus, for example, in the case where the network configuration is changed so that the terminal device is connected, with a load reduced in a short time.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a block diagram showing an example of configuration of an entire system according to the embodiment of the present invention. Figure 2 is a block diagram showing an example configuration of a digital satellite transmission receiver. Figure 3 is a block diagram showing an example configuration of a video recording and playback device. Figure 4 is a block diagram showing an example configuration of an audio recording and playback device. Figure 5 is a diagram showing an example of a frame structure prescribed by the IEEE 1394 scheme.

Figure 6 is a diagram showing an example of a structure of a space direction of the CRS architecture. Figure 7 is a diagram showing examples of positions, names, and functions of major CRSs. Figure 8 is a diagram showing examples of configuration of connection control registers. Figure 9 is a diagram showing configuration examples of oMPR, oPCR, iMPR, and iPCR. Figure 10 is a diagram showing an example of relationships between connections, connection control registers, and transmission comales. Figure 11 is a diagram showing an example of a data structure using a descriptor hierarchy structure. Fig. 12 is a diagram showing an example of a data structure of descriptors. Figure 13 is a diagram showing an example of a generation ID of Figure 12.

Fig. 14 is a diagram showing an example of a list ID of Fig. 12 Fig. 15 is a diagram showing an example of a stack model of an AV / C instruction. Figure 16 is a diagram showing an example of a relationship between instructions and responses of an AV / C instruction. Figure 17 is a diagram showing an example of a relationship between instructions and responses of an AV / C instruction in more detail. Fig. 18 is a diagram showing an example of a data structure of an AV / C instruction. Figure 19 is a diagram showing a concrete example of an AV / C instruction. Figure 20 is a diagram showing concrete examples of an instruction and a response of an AV / C instruction. Figure 21 is a flow diagram showing an example of a device processing discrimination according to an embodiment of the present invention. Fig. 22 is a flow diagram showing an example of device information acquisition process according to an embodiment of the present invention. Figure 23 is a diagram showing an example of a device information table according to an embodiment of the present invention. Figure 24 is a diagram showing an example of the format of an information instruction of a subunit according to the embodiment of the present invention. Figure 25 is a diagram showing an example of a format of a response to an information instruction of a subunit according to the embodiment of the present invention. Figure 26 is a diagram showing an example of a format of an information instruction of a unit according to the embodiment of the present invention. Figure 27 is a diagram showing an example of a form of a response to an information instruction of a unit according to the embodiment of the present invention. Figure 28 is a diagram showing an example of a subunit type according to an embodiment of the present invention. Fig. 29 is a diagram showing an example of a format of an open descriptor instruction according to the embodiment of the present invention. Figure 30 is a diagram showing an example of a format of a reading descriptor instruction according to the embodiment of the present invention.

Figure 31 is a diagram which shows an example of a format of a descriptor instruction of a disk subunit according to the embodiment of the present invention. Figure 32 is a diagram showing an example of data configuration of a media type of a descriptor of a disk subunit. Figure 33 is a diagram showing an example of a format of a tape reproduction instruction according to the embodiment of the present invention. Fig. 34 is a diagram showing an example of a format of a response to a tape playback instruction according to the embodiment of the present invention. Fig. 35 is a diagram showing an example of a directory of a unit of agreement to another embodiment of the present invention. Figure 36 is a diagram showing an example of correspondence between protocols and series of instructions according to another embodiment of the present invention. Figure 37 is a diagram showing an example of CTS according to another embodiment of the present invention. Figure 38 is a diagram showing an example of key data according to still another embodiment of the present invention.

THE BEST WAY TO CARRY OUT THE INVENTION Hereinafter, one embodiment of the present invention will be to describe with reference to the accompanying drawings. An example of configuration of a network system that the present invention has been applied will be described with reference to figure 1. In this network system, a plurality of devices are connected by a serial data bus 1 (hereinafter referred to as simply as bus 1) of the 1394 scheme of the IEEE. In Figure 1, there is a sample of an example in which 4 AV devices 100, 200, 300 and 400 are prepared and 3 AV devices 100, 200 and 300 are connected between them. Now it is assumed that the devices connected to the bus 1 are devices that each have a terminal to connect to a bus of the 1394 scheme of the IEE5, and the devices are an IRD Integrated Receiver Decoder 100 serving as a receiver of digital satellite transmission, a DVCR Digital Video Cassette Recorder (Digital Video Cassette Recorder) 200 that serves as a digital video recording and playback device, and an MD Mini Disc (Mini Disk) device 300 that serves as a recording device and digital audio reproduction. In the state shown in Figure 1, two MD (Mini Disk) devices 300 and 400 are prepared, and only the first MD 300 device is connected to bus 1. The second MD 400 device is not connected to bus 1 at this time. Here, electronic devices such as the IRD 100, DVCR 20C, and MD 300 and 400 devices that can be connected to bus 1 are called units. Between units, the information stored in the units can be mutually read and written using an instruction and a descriptor prewritten by AV / C Digital Interface Command Set General Specificactioa (hereinafter referred to as an AV / C instruction) of the Command Transaction Set AV / C. The details of the AV / C instruction are described in the AV / C Digital Interface Command Set General Specification open to the public at the 1394 Trade Association. In the AV / C instruction, each of the functions that the unit has is called a subunit. Acemas, each of the functions that the unit has is called a subunit. The IRD 100 for receiving and decoding digital satellite or similar transmission has a satellite dish 11 connected thereto. A digital tuner 12 connected to the parabolic antenna 11 conducts the process for receiving a signal from a predetermined and decoding channel. In this case a controller 13 incorporated in the IRD 100 effects a control concerning the reception operation as it is received and decoded. Both the channels that the IRD 100 can receive, audio channels from which only audio data such as tones are obtained, and data channels from which various data are obtained such as data for careful reading of the Internet network, also video channels (so-called channels for common television transmission) from which the audio data and video data are appended to the video data obtained. Like the audio data transmitted through the audio channels, there is audio data modulated by a common method such as the MPEG scheme, and channels from which the audio data is subject to a high coding compression efficiency such how the ATRAC (Adaptive Transform Acoistic Coding) scheme is obtained. In addition, the data transmission with the IRD 100 via the bus 1 is also controlled by the controller 13. In the data transmission via the bus 1, the controller 13 is adapted to be able to control the operation of other devices 200 and 300 connected by bus 1 for the use of instructions prescribed in the AV / C instruction described above. For example, the controller 13 can transmit audio data and video data from a video channel received by the IRD 100 to the DVCR 200., and controlling the recording operation on the DVCR 200 to record video and similar data on a video tape in a video cassette mounted on it. In this way you can record the video. In addition, the control 13 transmits audio data from an audio channel received by the IRD 100 to the MD 300 device, and controls the audio recording operation on the MD 300 device to record audio data on a magnetic optical disk mounted in this . When handling the manual reservation operation for audio or video recording on the IRD 100, it is also possible that, for example, it shows on screen a guide drawing of the program for EPG (Electric Program Guide) on a receiving television (not shown) connected to the IRD 100 and make reservations by manually operating a GUI Graphic User Interface (Graphical User Interface) on the basis of the sample on the screen of the guide drawing of the program on the screen. The DVCR 200 is a recording and playback device capable of recording video data, audio data, and data attached to it on a video tape as digital data and reproduction of that data from the video tape. Even, it is assumed that the DVCR 200 is a recording and playback device using a medium that has a format called D-VHS. A controller 21 of the DVCR 200 accepts the manual operation of the user to order the recording of video or playback or manual operation to reserve video recording, and to control the entire DVCR 200. on the control bases of the controller 21, an analog tuner 22 it extracts a signal from a predetermined channel from contained analog signals, converts the signal to digital data, and supplies the digital data to a recording tape and playback section 23. The recording tape and playback section 23 records video and data data of audio supplied from the analog tuner 22, or video data and audio data supplied from the IRD 100 or the like via bus 1 on a video tape. The MD 300 device is a recording and playback disc device capable of recording audio and data data appended to the audio data on a magnetic optical disc having a format called Mini Disc (MD), such as digital and playback data. the digital data from this one. A controller 31 of an MD 300 device accepts manual operation of the user to command audio recording or playback or manual operation to reserve audio recording, and controls the entire MD 300 device. A recording disc and playback section 32 records data of audio and as they are entered from the bus 1 or any other input section on a magnetic optical disk. As they are recorded on the disc in this case, the audio and other data are recorded as data arranged to encoded compression through the use of the ATRAC scheme. If audio data is transmitted via bus 1, it is ATRAC data, therefore, the transmitted audio data is recorded on the disk as it is. The MD 400 device that is not connected to the bus 1 in the state shown in Figure 1 is also a recording disk and playback device that has basically the same configuration as that of the MD 300 device. In other words, the MD 400 device is a recording disc and playback device capable of recording audio data and data appended to the audio data on a magnetic optical disc having a format called Mini Disc (MD) such as digital data and digital data reproduction from there . The MD 400 device includes a controller 41 and a recording disc and playback section 42. In addition, the MD 400 device includes a terminal for connection to the bus 1. When this terminal is connected to the bus 1, the MD 400 device can carry transmission data through the bus 1. Each of the controllers 13, 21, 31 and 41 respectively of the devices 100, 200, 300 and 400 includes a storage section for storing an AV / C descriptor equipment for the device. In addition, data as well as an instruction are required to read and write the descriptor that is also stored in the storage section. Figure 2 is a diagram showing a complete configuration of the example of the IRD 100. A radio wave transmission from a satellite is received by the antenna 8, placed in the terminal 100a, and supplied to a tuner 101 that serves as a means of the selection program provided in the IRD 100. In the IRD 100, respective circuits operate under the control of a central control unit (CPU) 111. A signal of a predetermined channel is derived by the tuner 101. The received signal is derived by the tuner 101 that is supplied to a descrambler circuit 102. On the basis of encryption of key information of a contracted channel stored in an IC card (not shown) that has been inserted into the main body of the IRD 100, the descrambler circuit removes only the multiplexed data from the contracted channel (or a non-encrypted channel) from the received data, and supplies the multiplexed data to a demultiplexer 103. The demlex iplexer 103 rearranges the multiplexed data supplied for each channel, it outputs only one channel specified by the user, sends a video stream formed of packets of video portions to an MPEG 104 video decoder and sends an overlapping stream formed of packets of audio portions to an MPEG 109 audio decoder. The decoder of video MPEG 104 restores the video data before it is contingent for decoding compression by decoding the video stream, and sends the video data to an NTSC 106 encoder via an add-on 105. The NTSC 106 encoder converts the video data to a luminous signal and a signal of different colors of the NTSC scheme, and send the light signal and the signal of difference Various colors for an ultralight to analog converter 107 such as the video data of the NTSC scheme. The digital-to-analog converter 107 converts the NTSC data to a analog video signal, and supplies the analog video signal to a connected television receiver (not shown). The IRD 100 of the present example includes a GUI 108 data generation section for generating different video data to be displayed on the screen for the graphic user interface (GUI) under the control of the CPU 111. The video data (data on the screen) for the GUI generated by the data generation section GUI 108 is supplied to the adder 105, and is superimposed on the video data taken from the MPEG 104 video decoder. In this way the image for the GUI is superimposed on the image of the received transmission. An MPEG audio decoder 109 re-establishes the PCM audio data before it is subjected to coding compression by decoding the audio stream, and sends the PCM audio data to an analog digital converter 110. The analog digital converter 110 converts. PCM audio data to an analog signal to generate an L-Ch audio signal and an R-Ch audio signal. The audio signal L-Ch and the audio signal R-Ch are output as sound by a speaker (not shown) of a connected audio playback system. In addition, the IRD 100 of the present example has such a configuration that the video stream and the audio stream extracted by the demultiplexer 103 can be supplied to an IEEE 112 1394 interface section and sent to the bus line 1 of the connected IEEE 1394 scheme to the interface section 112. The received video stream and audio stream are sent out in an isochronous transferred mode. When the data generation section of the GUI 108 is generating video data for the GUI, the video data is supplied to the interface section 112 by the CPU 111 and the video data for the GUI can be sent out from the interface section 112 to the bus line 1. A work RAM 113 and a RAM 114 is connected to the CPU 111. The process control is conducted by these memories. In addition, a manual operation is ordered from a manual operation panel 115 and a remote control signal from a section receiving infrared rays 116 is supplied to the CPU 111, operation based on various manual operations can be executed. In addition The CPU 111 can distinguish instructions and responses transmitted from the bus line 1 to the interface section 112. Figure 3 is a block diagram showing an example configuration of the DVCR 200. As for the configuration of a recording system , the transmitted digital data obtained by receiving a predetermined channel in a tuner 201 incorporated in the DVCR 200 is supplied to an MPEG encoder (Moving Picture Experts Group), and converted to video data and audio data of an appropriate scheme for recording, such as the 2 MPEG scheme. If the transmitted data received is data of the MPEG scheme 2, the process is not carried out in the encoder 202. The data encoded by the MPEG encoder 202 is supplied to a recording and playback section 203, and is subjected to the recording process. . The data to be recorded in this processed manner is supplied to a rotating head included in a rotating cylinder head 204, and recorded on a magnetic tape in a tape cassette 205. As for an analog video signal and an analog signal. audio input from the outside, converted to digital data by an analog-to-digital converter 206, the converted video data and audio data of, for example, the MPEG 2 scheme, using the MPEG 202 encoder, supplied for the recording section and reproduction 203, and subject to the recording process. The data to be recorded as well as processed are supplied to the recording head included in the rotary cylinder head 204, and recorded to the magnetic tape in the tape cassette 205. As would be the configuration of a reproduction system, a Signal obtained by a magnetic tape reproduction in the tape cassette 205 using the rotary cylinder head 204 is subject to the reproduction process in the recording and playback section 203 to produce video data and audio data. The video data and audio data are supplied to an MPEG decoder 207, and decoded from, for example, the MPEG 2 scheme. The decoded data is supplied to a digital to analog converter 208. An analog video signal and an analog audio signal thus obtained is carried out. The DVCR 200 includes an interface section 209 for connecting to a bus of the 1394 IEEE scheme. The DVCR 200 is formed so that the video data and audio data supplied from the bus side of the IEEE 1394 scheme to the interface section 209 can be supplied to the recording and playback section 203 and recorded on a magnetic tape in the cassette. In addition, the DVCR 200 is formed so that the video data and audio data reproduced from the magnetic tape in the tape cassette 205 can be supplied from the recording and playback section 203 to the interface section 209 and sent to the bus side of the 1394 IEEE schema. When the transmission is carried out by the interface section 209, and the scheme (such as that described above in the MPEG scheme 2) for recording data on a medium (magnetic tape) in the DVCR 200 is different from the scheme of The data transmitted to the bus of the 1394 IEEE scheme, the schematic conversion can be carried out in a circuit in the DVCR 200. The recording process and the reproduction process carried out in the DVCR 200 and the transmission process carried out in the The interface session 209 is executed under the control of the central control unit (CPU) 210. A memory 211 serves as a working RAM and is connected to the CPU 210. In addition, manual operation information from a control panel is provided. manual operation 212 and control information is output by a remote control device and received in the form of light by infrared rays in the receiving section 213 are supplied to the CPU 210. The control action with It corresponds to the manual operation information and control information is carried out. Further, when the interface section 209 has received control data such as an AV / C instruction later described by the bus of the 1394 IEEE scheme, the data is supplied to the CPU 210 so that the CPU 210 can perform the corresponding control operation. . Figure 4 is a diagram of the block showing an example configuration of an MD 300 device. The MD 300 device serves as an audio recording device and reproduction is a device for recording and reproducing an audio signal and therefore on Digital data by using a magnetic optical disc or an optical disc covered in a resin package called MD (Mini Disc) as a recording medium. As for the configuration of a recording system, a two-channel audio signal inputted from the outside is converted to digital audio data by an analog to digital converter 301. The digital audio data thus obtained by the conversion is supplied to an ATRAC 302 encoder. audio compressed in the ATRAC scheme are obtained by coding. In the case where the digital audio data is directly entered from the outside. The entered audio data is supplied directly to an encoder 7 ^ TRAC 302 without passing through the analog to digital converter 301. The data encoded by the encoder 302 is supplied to a recording and playback section 303 and is subject to the recording process . On the basis of the data processed in this way, an optical sorter 304 is operated and the data is recorded on a disk 305 (magnetic optical disk) at the time of recording, the magnetic field modulation is conducted by means of the magnetic head that does not it shows. As for the configuration of a reproduction system, the data recorded on a disk (optical disk or magnetic optical disk) 305 is read by the optical sorter 304, and subject to the reproduction process in the playback and recording section 303. this way the compressed audio data is obtained in the ATRAC scheme. The reproduced audio data is supplied to an ATRAC decoder 306 and decodes the digital audio data of a predetermined scheme. The decoded audio data is supplied to a digital to analog converter 307, converted to an analog audio signal from god channels, and outputted. In the case where the digital audio data is output directly to the outside, the audio data decoded by the ATRAC decoder 306 is output directly without passing through the analog digital converter 307. The example of FIG. 4 has such a configuration that the signal output audio subject to analogous conversion is administered to an amplifier device 391 and subject to the auclio output process such as amplification and a two-channel audio output is subjected from the connected speakers 392 and 393. The MD 300 device includes an interface section 308 for connection to the bus of the 1394 IEEE scheme. The MD 300 device is formed so that the audio data supplied from the bus side of the IEEE 1394 scheme to the interface section 308 can be supplied to the recording and playback section 302 via the encoder 302 and recorded on the disk 305. In addition, the MD 300 device is formed so that the audio data reproduced from the disk 305 can be supplied from the recording and playback section 302 to the interface section 308 via the ATRAC 306 decoder and sent to the bus side of the 1394 scheme IEEE. The recording process and the reproduction process carried out in the MD 300 device and the transmission process carried out by the interface section 308 are executed within the control of the central control unit (CPU) 310. A memory 311 which serves as a work RAM is connected to the CPU 310. In addition, manual operation information from a manual operation panel 312 is supplied e. CPU 310. The control action corresponding to the manual operation information is carried out. Further when the interface section 308 receives control data such as an AV / C instruction later described by the IEEE 1394 schema bus, the data supplied to the CPU 310 so that the CPU 310 can perform the corresponding operation control. A state of data transmission on the bus 1 of the 1394 IEEE scheme connects the devices 100, 200 and 300 to one another as described now. Figure 5 is a diagram showing a data transmission cycle structure of devices connected by the 1394 IEEE. According to the 1394 IEEE, the data is divided into packets and the packets are transmitted in a time division so that they can take a cycle that has a length of 125 μs as a reference. This cycle is produced by a signal start cycle supplied from a node that has a master cycle function (some device connected to the bus). Isochronous packets ensure a band (which is called a band although it is a unit of time) required for transmission from the head of each cycle. So, in isochrone transmission, the data transmission is secured in a fixed time. However, the recognition from the side that receives is not carried out. If a transmission error occurs, there is no mechanism for protection and loss of data. During the time of each cycle that is not used for isochronous transmission, a node that has the bus secured as a result of arbitration sends asynchronous packets. In this asynchronous transmission, secure transmission is ensured through the use of recognition and retry. However, the transmission time does not adjust. For a predetermined node to be able to drive isochronous transmission, the node must correspond to the isochrone function. In addition, at least one of the nodes corresponding to the isochrone function must have a master function cycle. In addition, at least one of the nodes connected to the serial bus 1394 I? EE must have an isochronous resource handling function. The 1394 IEEE is conformed to a CSR architecture (control and status register) that has a 64-bit address space prescribed by ISO / IEC 13213. Figure 6 is a diagram showing the structure of the address spaces of the CSR architecture. 16 high-order bits are used for an ID node indicating each node on the 1394 IEEE. The remaining 48 bits are used to specify a given address space for each node. The high order 16 bits are further divided into 10 bits of an ID bus and 6 bits of a physical ID (an ID node of an arrow direction). It has a value of 1 in each bit used for special purpose. Therefore, 1023 buses and 63 nodes can be specified. Upon re-establishment of the bus, the ID nodes are again provided. Bus re-establishment occurs when the configuration of the devices connected to bus 1 has changed. For example, bus re-establishment is executed, when it is recognized that any of the devices connected to bus 1 is removed or a device is connected back to bus 1. In an address space of 256 tera bits prewritten by 48 bits of order under, a prewritten 20-bit high-order space is divided into an initial record space of 2,048 bytes to be used by specific registers for CSR and specific records for the 1394 IEEE, a private specimen, and an initial memory space, in the case where the space prewritten by 20 bits of high order is the initial registration space, it is used as a configuration of ROMs (read only memory), an initial unit space is used for specific application for the node, and registers of Connection control (PCRs). Figure 7 is a diagram showing copies of addresses, names, and functions of the major CSRs. The copy of Figure 7 denotes an address copy compared to an address FFFFFOOOOOOOh where the initial registration space begins, (numbers that have an h at either end are expressed by hexadecimal notation). An available register of bandwidth having a 220h copy indicates a band that can be assigned to isochronous communication, and only the value of the operation of the node as the isochronous resource handler becomes valid. That is, each node has the CSRs shown in Figure 6. As for the available bandwidth record, however, only what the isochronous resource handler becomes valid. In other words, substantially only the isochronous resource handler has the available bandwidth registry. The available record of bandwidth. Maintains a maximum value when no band is assigned to isochronous communication. Each time a band is assigned, the value decreases. In the channel of available registers of copies 224h to 228h, the respective bits correspond to channel numbers 0 to 63, respectively. If a bit is 0, it indicates that the channel has already been assigned. Only the available channel record of a node that serves as an isochronous resource handler is valid. With reference again to figure 6, a ROM configuration based on a general ROM format (read-only memory) is accommodated in 200h to 400h addresses in the initial registration space. In the ROM configuration, an information block bus, a directory path, and a unit directory are accommodated. In a company ID on the bus in the information block, an ID number indicates a fabrication of the stored device. In a chip ID, there is stored an ID that is unique to the device and unique in the world where it has no duplicate with other devices. To control the input and output of a device through an interface, each node has a PCR (connection control register) prewritten in 1883 IEC, in the address 900h to 9FFh in the initial unit space of figure 6. This is has obtained by substantializing the concept of a connection to logically form a road signal similar to an analogous interface. Figure 8 is a diagram showing a PCR configuration. The PCR has an oPCR (connection control output register) representing an output connection and an iPCR (connection control input register) representing an input connection. In addition, each PCR has an oMPR register (master output connection register) and an iMPR register (input master connection register) respectively indicating information of an output connection or a specific input connection to the device. Each device does not have a plurality of oMPRs and iMPRs. However, each device may have a plurality of oPCRs and iPCRs corresponding to individual connections, according to the. capacity of this. Each of the PCRs shown in Figure 8 has 31 oPCRs and 31 iPCRs. The isochronous data flow is controlled by the corresponding operation registers of these connections. Figure 9 is a diagram showing the configurations of oMPR, oPCR, iMPR and iPCR. Figure 9A shows a configuration of the oMPR. Figure 9B shows a configuration of the oPCR. Figure 9C shows a configuration of the iMPR. Figure 9D shows a configuration of the iPCR. In a 2-bit "data rate capability" of the MSB side of each of the oMPR and iMPR, a code indicating a maximum speed transmission of isochronous data that can be transmitted or received by the device is stored. An oMPR transmission base channel prescribes the number of a channel that is used by a transmission output. In a 5-bit "number of output connections" on the LSB side of the oMPR, the number of output connections that the device has, that is, a value that indicates the number of oPCRs, is stored. In a 5-bit "number of input connections" on the LSB side of each iMPR, the number of input connections that the device has, that is, a value indicating the number of iPCRs, is stored. A main extended field and an extended field subsidiary are defined areas for future extensions. An "online" of an MSB from each of the oPCRs and iPCRs indicate the use of the connection state. In other words, the online value that has a "1" that indicates that the connection is online and the online value that has "0" indicates that the connection is offline. A value of a "transmission connection counter" of each of the oPCRs and iPCRs indicates whether there is a transmission connection (1) or not (0). A value of a "point-to-point connection counter" has a width of 6 bits in each of the oPCRs and iPCRs that represents the number of point-to-point connections that the connection has. Point-to-point connection (also called p-p connection) is a connection to carry transmissions only between a specific node and another specific node. A value of a "number of channels" has a width of 6 bits in each of the oPCRs and iPCRs that represents the number of isochronous channels to which the connection is connected. A value of a "speed data "has a width of 2 bits in each of the oPCRs that indicates the current transmission speed of a packet of isochronous data taken from that connection.A code stored in an" upper ID "has a width of 4 bits in each one of the oPCRs that indicates the bandwidth of the upper isochronous communication A value of a "payload" has a width of 10 bits in each of the oPCRs that indicates a maximum value of data contained in an isochronous packet that the connection can handle Figure 10 is a diagram showing the relationship between connections, connection control registers, and isochronous channels. In Figure 10, the devices connected to the bus of the 1394 IEEE scheme are shown as AV devices 71 to 73. The isochronous data specified in the channel by an oPCR [1] between oPCR [0] to oPCR [2] prewritten in the speed transmission and the number of oPCRs through an oMPR of the AV 73 device is sent out of channel # 1 of an IEEE 1394 serial bus. Between the iPCR [0] and iPCR [1] prewritten in the transmission speed and the number of iPCRs by an iMPR of the AV 71 device, the transmission speed and the iPCR [0] specifies the input channel # 1. The AV 71 device reads isochronous data sent out of channel # 1 of the IEEE 1394 serial bus. In the same way, the AV 72 device sends isochronous data out of channel # 2 specified by the oPCR [0]. The AV 71 device reads isochronous data from channel # 2 specified by the iPCR [1]. In this way, data transmission is carried between devices connected by the 1394 serial IEEE bus. In the system of the present example, however, control decision and respective device status can be carried out by using a series of AV / C instructions preset as instructions for controlling devices connected by the IEEE 1394 serial bus. The series of AV / C instructions will now be described. First of all, a data structure of a subunit identifier descriptor in the instruction series AV / C used in the system of the present example will be described with reference to Figs. 1 to 14 Fig. 11 shows a descriptor data structure subunit identifier. As shown in Figure 11, the subunit identifier descriptor is made up of lists that each have a hierarchical structure. In the case of a tuner, the lists represent channels. In the case of a disc, the lists represent songs recorded on it. A list of higher layers of a hierarchy structure is called a root list. For example, a zero list becomes a root for its subordinate lists. In the same way, other lists are made root lists. There are as many root lists as there are objects. For example, in the case where the AV devices connected to the bus are tuners, the objects are channels in digital transmission. In addition, all lists in a hierarchy class share common information. Figure 12 shows a format of a subunit identifier descriptor. In the general subunit identifier descriptor, information is attributed concerning the function that is described as its content.

A "descriptor field length" does not contain the value of its same field. An "ID generation" indicates the version of the AV / C instruction series. This value is, for example, "OOh" (where h represents the hexadecimal notation). As shown in Figure 13, for example, "OOh" means that the data structure and instructions conform to version 3.0 of the general AV / C specification. In addition, as shown in Figure 13, all values except "OOh" are reserved and secured for future specifications. An "ID list size" indicates the number of bits in an ID list. an "ID object size" indicates the number of bits of an ID object. An "object position size" indicates the position (the number of bits) in the list to be used for reference to the control time. A "root object list number" indicates the number of root object lists. A "root object ID list" indicates an ID to identify a root object list of the highest rank of each of the hierarchically independent classes. A "dependent length of the subunit" indicates the number of bits of a subsequent "subunit-dependent information" field. The "subunit dependent information" field is a field that indicates particular information of the function. A "manufacturer-dependent length" indicates the number of bits in a subsequent field "of manufacturer-dependent information". The "manufacturer-dependent information" field is a field that indicates the specific information of a vendor (manufacturer). If the descriptor does not contain "manufacturer-dependent information", the "manufacturer-dependent information" field is not present. Figure 14 indicates the allocation of list range IDs shown in Figure 12. As shown in Figure 14, the "OOOOh to OFFFh" and "4000h to FFFFh" are reserved and secured as allocation ranges for future specifications. To identify information dependent on the type function, "lOOOh to 3FFFh" and "lOOOOh to the maximum value of the ID list" are prepared. With reference to Figures 15 to 20, the series of AV / C instructions used in the system of the present example will now be described. Figure 15 shows a stack model of the AV / C instruction series. As shown in Figure 15, a physical layer 81, a link layer 82, a transaction layer 83, and a serial bus driver 84 make up the 1394 IEEE. An FCP (Control Protocol Function) 85 is conformed for IEC 61883. A series of AV / C 86 instructions is compliant for the 1394 TA specifications. Fig. 16 is a diagram showing an instruction and a response of the FCP 85 shown in Fig. 15. The FCP is a protocol for effecting a device control (nodes) on the bus of the 1394 IEEE scheme. As shown in Figure 16, the control side is a controller and the controlled side is a target. The instruction and transmission c.e response of the FCP are conducted between nodes by using the described transaction of asynchronous communication of the 1394 IEEE. On the received data, the objective returns an acknowledgment to the controller to recognize the reception. Figure 17 is a diagram showing the relationship between the instruction and response of the FCP of Figure 16 in more detail. A node A and a node B are connected by an IEEE 1394 bus. Node A is the controller, and node B is the target. In both the node A and the node B, an instruction register and a response register are prepared each having 512 bits. As shown in Figure 17, the controller transports an instruction by writing an instruction message within an instruction register 93 of the target. Otherwise, the target carries a response by writing a response message within a response register 92 of the controller. For the two messages, control information is exchanged. The type of a series of instructions sent by the FCP is described in the CTS included in a data field shown in Figure 18 and described later. Figure 18 shows a data structure of a packet transmitted in an asynchronous transfer mode of the AV / C instruction. The AV / C instruction series is a series of instruments for controlling an AV device., and its CTS (ID of the instruction series) = "0000". Instruction frames and AV / C response frames are exchanged between the nodes using the FCP described above. To prevent the emptying of a load on the bus and the AV device, a response to an instruction is defined to be sent within 100 ms. As shown in Figure 18, the data of an asynchronous packet has 32 bits (= 1 quadlet) in the horizontal direction. The highest columns of Figure 18 show a header portion of the packet, and the lower columns of Figure 18 show a block of data. A destination ID indicates the destination. The CTS indicates an ID of a series of instructions. In the instruction series AV / C, CTS = "0000". A type / response C field indicates a function class of an instruction when the packet is an instruction, and a processing results from an instruction when the packet is a response. The instructions are broadly divided into 4 types: (1) instructions (CONTROL) to control the function from the outside; (2) instructions (STATUS) to investigate the state of the exterior; (3) instructions to ask if a control support instruction is present, from the outside (GENERAL INQUIRY (if a support of an operation code is present) and SPECIFIC INQUIRY (if the support of an operation code is present and operating)); and (4) instructions (NOTIFY) to request the news of a change of status abroad. A response is returned according to the type of instruction. As responses to the CONTROL instructions, they are "NOT IMP EMENTED", "ACCEPTED", "REJECTED" and "INTERIM". As a response to the STATUS instructions, they are "NOT IMPLEMENTED", "REJECTED", "IN TRANSACTION" and "STABLE". As answers to the instructions to ask if the support of an instruction is present, from the outside (GENERAL INQLIRY and SPECIFIC INQUIRY), are "IMPLEMENTED" and "NOT IMPLEMENTED". As responses to the instructions to request the news of a change of status abroad, they are "NOT IMPLEMENTED", "REJECTED", "INTERIM" and "CHANGED". A "subunit type" is provided to specify a function in the device. For example, a "tape recorder / player", "tuner", or similar is assigned. In addition, the function corresponding to the device, BBS (bulletin of the subunit card) which is a subunit of information open to other devices is also assigned to the "subunit type". To distinguish in the case where there is a plurality of subunits of the same type, the addressing is conducted using an ID subunit as a characteristic number. An "operation code" that is an operation code that represents an instruction. An "operand" that represents a parameter of the instruction. Additional operands are also prepared that are added as occasional demands. After the operands, the data "0" or similar ones are added. CRC data (cyclic redundancy check) is used to verify an error at the time of data transmission. FIGURE 19 shows a concrete example of an AvVC instruction. The left side of FIGURE 19 shows concrete examples of a response / type c. Your upper column shows instructions and your lower column shows answers. "CONTROL" is assigned to "0000". "STATUS" is assigned to "0001". "SPSCIFIC INQUIRY" is assigned to "0010". "NOTIFY" is assigned to "0011". "GENERAL INQUIRY" is assigned to "0100". From "0101 to 0111" they are reserved and secured for future specifications. "NOT IMPLEMENTED" is assigned to "1000." "ACCEPTED" is assigned to "1001." "REJECTED" is assigned to "1010." "IN TRANSITION" it is assigned to "1011." "IMPLEMENTED / STABLE" is assigned to "1100." "CHANGED" is assigned to "1101." "INTERIM" is assigned to "1111." "1110" is reserved and secured for future specifications. The center of FIGURE 19 shows concrete examples of the subunit type "Video screen" is assigned to "00000." "Player disc / recorder" is assigned to "00011".

"Tape player / recorder" is assigned to "00100". "Tuner" is assigned to "00101". "Video camera" is assigned to "00111". A subunit called BBS (subunit card bulletin) and used as a card bulletin is assigned to "01010". A manufacturer's dependent of the subunit type (sole seller) is assigned to "11100". A specific subunit type (subunit type extends to the next byte) is assigned to "11110". "Unit" is assigned to "11111", and it is used when the instruction or response is sent to the device itself. For example, you can mention turning on and off the power supply. The right side of FIGURE 19 shows concrete examples of operation codes (operation codes). For each of the subunit types, there is a table of operation codes. In FIGURE 19, operation codes are shown in the case where the subunit type is the "tape recorder / player". In addition, for each operation code, an operand is defined. Here, a manufacturer-dependent value (dependent on the vendor) is assigned to "OOh". The "search mode" is assigned to "50h". The "time code" is assigned to "51h". The "ATN" is assigned to "52h". The "open memory" is assigned to "60h". The "read memory" is assigned to "61h". The "write memory" is assigned to "62h". The "loaded" is assigned to "Clh". The "audio recording" is assigned to "C2h". "Playback" is assigned "C3h". The "rewind" is assigned to "C4h". FIGURE 20 shows concrete examples of an AV / C instruction and an AV / C response. For example, in the case where a playback order is going to be given to a playback device that serves as the target (client), the driver sends the instructions as shown in FIGURE 20A to the target. In this instruction, CTS = "0000" because the AV / C instruction string is in use. After the instruction (CONTROL) is used to control a device from the outside, type c becomes type c = "0000" (see FIGURE 19). After the subunit type is a tape recorder / player, it is followed by the subunit type = "00100" (see FIGURE 19). In addition, the "id" indicates the case of IDO, and id = 000. The operation code becomes "C3h" which means reproduction (see FIGURE 19). The operand becomes "75h" which means the forward direction (FORWARD). Upon playback, the target returns a response as shown in FIGURE 20B to the controller. After it is "accepted" it is included in the response. The answer follows = "1001" (see FIGURE 19). Except for the answer, other fields are the same as those in FIGURE 20A, and the description thereof will be omitted. It is now assumed that the data transmission based on the AV / C instruction is carried out in the system of the present example described hitherto. The process of recognizing a device connected to the bus 1 will now be described. First, in the network system formed by connecting devices with the bus 1 of the 1394 IEEE scheme, each device has a unique single node ID already described. Regardless of the unique ID node, an ID node is established within the network. Upon bus reset, the ID node is set individually for each device of each unique ID node. If there is a bus reset, in the case of the present example, the controller 13 in the IRD 100 processes discriminates the types of other devices connected to the bus 1 (the DVCR 200 and the MD 300 device) by using an instruction and a descriptor prescribed in the AV / C instruction. Hereinafter, the discrimination process of the type of connected devices will be described with reference to the flow diagrams of FIGURES 21 and 22 and to the data configurations of FIGURE 23 and subsequent drawings. First, as shown in the flow diagram of the FIGURE 21, el. controller 13 in the IRD 100 determines whether the process of restoring the bus resets the single node ID and thus bus 1 has been carried out (step Sil). By making a judgment of the restoration of the bus to be carried out, the controller 13 transmits a SUBUNIT INFO instruction prescribed in the AV / C successively to devices connected to the bus 1 (step S12). The details of the SUBUNIT INFO instruction will be described later. The SUBUNIT INFO instruction is an instruction that the devices corresponding to AV / C need to have. When there is a correct answer to this instruction, the device of the opposite party is known to be the device corresponding to the AV / C. After the controller 13 in the IRD 100 has transmitted the SUBUNIT INFO instruction, the controller 13 determines whether the response data prescribed in AV / C has been returned to the IRD 100 (step S13). If the data response is not transmitted, the controller 13 judges the discrimination of the relevant devices using the AV / C instruction that are impossible (step S27). When the data response is transmitted to step S13, the controller 13 judges the type of subunit indicated by the data response (step S14). Details of the subunit type that may be discriminated will be described later. However, in the AV / C, it is possible to discriminate at least one unit (device) of such type that a disk is handled as the medium, a unit (device) of such type that a tape (magnetic tape) is handled as the medium, and a unit (device) of another type.

If in the decision of step S14 in the controller 13 it is considered that the subunit that the unit of the opposite party of the communication has a subunit of a type of a disk is handled as the medium, then the controller 13 drives the reading process a descriptor that has the opposite side. To read the descriptor, the controller 13 first transmits an instruction of the OPEN descriptor control which is an instruction to open the descriptor of a pertinent unit (step S15). The controller 13 then determines if there is a return of the relevant device, for the transmission of the instruction (step S16). If there is a return, the controller 13 transmits an instruction of the READ descriptor control which is an instruction to read the open descriptor (step S17). In addition, the controller 13 determines if there is a return from the relevant device, for the transmission of the instruction (step S18). If there is a return, the controller 13 considers the data content of the media type included in the data of the returned descriptor, and determines whether the code has an MD media type (mini disk) (step S19). On the jugend of the code to be an MD code, the controller 13 of the IRD 100 recognizes the relevant device as an MD device (step S20). If there is no return instruction to step S16 or S18, or if the media type is not considered to be an MD at step S19, the controller 13 recognizes the relevant device as a disk device handling a disk of another format (step S21). ). If the subunit the unit of the opposite side of the communication has a consideration as in step S14 in the controller 13 it will be one of the tape handling type as its medium, then the controller 13 carries out the process of asking about the format used by the opposite party to play the tape. In other words, the controller] 3 transmits the status instruction of a TAPE PLAYBACK FORMAT to inquire about the tape playback format on the bus 1 (step S22). And the controller 13 determines if there is a return from the relevant device for the transmission of the instruction (step S23). If there is a return, the controller 13 determines whether the question about the tape reproduction format is valid. To be specific, the controller 13 determines whether the return is a response other than the response "NOT IMPLEMENTED" which is a response that can not be responded to the transmission of a status instruction carried out in step S22 (step S24) . When controller 13 has considered the response to be a different instruction than "NOT IMPLEMENTED", the controller 13 recognizes the relevant unit as a DVCR of the D-VHS standards (step S25). If there is no response instruction to step S23, or if the response is considered to be a "NOT IMPLEMENTED" instruction to step 24, the controller 13 recognizes the device as a tape device that handles tape of a different format (step S26). Further, if the decision of a subunit type to step S14 is considered to be the subunit type different than a disk and tape, the controller 13 recognizes the device as a device of a different type (step S28). The IRD 100 executes the process described hereinabove successively for respective devices connected to the bus 1, discriminating the types and thus all the devices connected to the bus 1, and stores and maintains the data thus discriminated in the storage section prepared in the controlled one: After the IRD has discriminated the respective types and devices, the IRD 10 collects the data concerning the respective devices. With reference to the flow diagram of FIGURE 22, the process of collecting data concerning the respective discriminated devices executed in controller 13 of the IRD 100 will now be described. First, it is determined whether there is a change in the topology of the network (step S31). Here, the topology of the network is considered to have a change when the restored bus is carried out and henceforth the discrimination process of the respective device type is carried out (ie the process of the flow chart of FIGURE 21 is executed). If the network is considered to have change, then the controller 13 sends an instruction to ask predetermined characteristic data for all the devices connected to the bus 1 included in the network, which here are unique nodes IDs, of the respective devices. The controller 13 of the IRD 100 considers the responses for the instruction, and considers the unique nodes IDs of the respective devices (step S32). In this way, if the unique nodes IDs of the respective devices in the network have already been obtained by, for example, the process of the flow chart of FIGURE 21, the controller 13 reads the unique nodes IDs acquired and stored for consideration. Here, the controller 13 determines whether the data concerning the devices in the network configuration precedes the detection of the changed topology of the network conducted in step S31 are retained in the storage section prepared in the controller 13 (step S33). ). If in this decision the data of the previous device is considered not to be maintained, then the controller 13 sends instructions successively to all the devices in the network to make them transmit data concerning the devices, and conducts the process for the storage of data returned in response to the instruction in the storage section prepared in controller 13 (step S34). The process carried out in step S34 is common device information acquired from the process conventionally carried out. If in the decision of step S33 of the above device the data is considered to have to be maintained, the controller 13 determines whether there is a device having an ID that is included in the unique nodes IDs of the respective devices considered in step S32 and that is different from the single node ID of the device stored in the storage section (step S35). If in this decision a device having a unique ID node different from the stored ID is considered to be present, the controller 13 sends an instruction to the device having the relevant unique ID node to cause the device to send the data concerning the device, and conduct the process for storing data returned in response to the instruction in the storage section prepared in controller 13 (step S36). About carrying out the process described here until now, the controller 13 causes only data concerning the devices currently connected to the network to be preserved and other data to be deleted, and in this way cause the last data in the network to be preserved (step S37). In other words, if the information acquired from the process is carried out in step S34, the controller 13 causes all the acquired data to be conserved as the network data. If a different device from any of the data devices that is retained is considered to step S35 is not present, the controller 13 causes the previously stored data to be retained as they are in the network data. (However, if a previously connected device disappears, the controller 13 causes the data concerning the device to be erased). If the presence of a different device is detected in step S35 and if the data of some devices is obtained in step S36, then the controller 13 causes the data of the network to be registered with the acquired data to be preserved. In this way, the unique nodes IDs used as particular data for respective devices in the process described above are identified as data respectively provided for the devices connected to bus 1 of the IEEE 1394 scheme, one by one. For example, as shown in FIGURE 23, the unique ID node of each device is formed of a predetermined number of bits. From the data of a predetermined number of bits in the data, the device type of the device (representing what type of device is made) and the name of the vendor as well as the name of the manufacturer of the device can be known. In summary, the data corresponding to a serial code such as a manufacturing number of each device is also inserted. Even if the devices have the same form and are manufactured by the same company, their unique nodes IDs are made data of different values. A unique ID node as shown in FIGURE 23 is stored in the storage section in controller 13 of IRD 100 as well as to be associated with, for example, each node ID. (After the ID is reproported at the time of, for example, bus reset, it is not necessarily constant every time). In this way, the process of collecting data from respective devices connected to the network is carried out. In this case where the least data of the device before the bus is reset remains and only some devices differ between the network before the bus is reset and the current network, therefore, it is necessary to collect only data concerning the devices different Therefore, the amount of process for collecting device data on the network is reduced. The data collection load can be reduced. In summary, the time required for the collection of device data can be shortened. For example, it is assumed in the case of the configuration of the network shown in FIGURE 1 and already described that the MD 400 device is connected again to bus 1 and the bus reset is applied. Only the data concerning the MD 400 device does not exist in the storage section of the controller 13 of the IRD 100. The data of other devices 200 and 300 are stored there. Therefore, it is only necessary to ask the controller 41 of the MD 400 device to transmit the data concerning the device 400. As compared with the case where all the devices are requested to transmit data, the quantity process and the time process required to register the data of the network can be substantially reduced. Furthermore, in the case where some devices are disconnected from bus 1 and with which the bus reset is applied, it is only necessary to delete the data concerning the devices in the same way, therefore, new network data is obtained through a simple process. The subunit information status instruction in the AV / C instruction is defined by the format shown in FIGURE 24. In FIGURE 24, eight bits are shown as one unit (one line shown in the lateral direction). (It is also true in the format of the diagrams in FIGURE 25 and subsequent drawings.) The subunit information response in the AV / C instruction is defined by the format shown in FIGURE 25. Operational code and operand data which are shown in FIGURES 24 and 25 are placed in the fields of the operation code and c >; perandos in the FCP framework included in the package shown in FIGURE 18. In the subunit information status instruction shown in FIGURE 24, the subunit information data is placed as the operation code. The data of a page and extension code are placed in an area of an operand [0]. In an area of an operand [1] and subsequent operands, a specific value (.here FF) is placed. In the response for this instruction, the data on the page is placed in an area of an operand [1] and subsequent operations as shown in FIGURE 25. The areas of an operation code and an operand [0] of the response they are the same as those of the instruction. In the flow chart example in FIGURE 21, the subunit type is asked to consider the type of the device. However, you can ask the type of unit. A unit information status instruction to inquire about the unit type is defined by the format shown in FIGURE 26. A unit information response serves as its response is defined by a format shown in FIGURE 27. In the instruction of the unit training state shown in FIGURE 26, the information data is placed as the operation code. In an area of an operand [0] and subsequent operands, a specific value (here FF) is placed. In the response for this instruction, the unit type data in the unit is placed in an area of an operand [1] as shown in FIGURE 27. In addition, in operands [2] to [4], it is placed a company ID that is a provided code that each company has manufactured for each device (unit). Some of the codes concerning the subunit type prescribed in the AV / C instruction are shown in FIGURE 28. FIGURE 38 shows some of the subunit types already shown in FIGURE 19, again. Here, the video screen, recorder and / or disc player, tape recorder and / or tape player, tuner, video camera, and so on are prescribed as subunit types. In addition, a subunit type has a special format prescribed by each company is prescribed as a single seller value. By judging the data of this type of subunit, the controller 13 of the IRD 100 can decide the type of subunit that the device has on the opposite side. In the case of the AV / C instruction, an instruction to open the descriptor (instruction to open the descriptor) is required after a decision that has been made by the subunit type if the type that is decided is "disk" is prescribed in a format shown in FIGURE 29. In this instruction to open the descriptor, the data indicates that an open descriptor is placed as an operation code, and the data for descriptor identification and sub-function data are placed as the operands . In the case of the AV / C instruction, an instruction to read the descriptor (descriptor reading instruction) after the descriptor has been opened by the instruction to open the descriptor is prescribed in the format shown in FIGURE 30. In this descriptor reading instruction, the data indicate that a read descriptor is placed as the operation code, and the data for the identification of the descriptor, reading data results state, data length, and address reading data are placed as operands. FIGURE 31 is a diagram showing an example configuration of a descriptor of a disk type subunit in the AV / C instruction read by the instruction described above. The descriptor has data of a hierarchical structure. An example of a subunit identifier disc descriptor is shown in FIGURE 31. For example, a descriptor length, a generation ID, a size of a list ID, a size of an object ID, a size of an object position, the number of root object lists, a root object ID ista, a data length data unique to the disk subunit, unique information for the disk subunit, a length of data data unique to a manufacturer, information unique to the manufacturer are placed. As for the list of root object IDs, each list of root object IDs are indicated by the data of the number of root object lists are placed. As for the data of a disk subunit depends on information that is unique information to a subunit of. disk contained in the disk subunit identifier descriptor, has a configuration shown in FIGURE 32. A copy of the address shown in FIGURE 32 is a copy value of an address from an operand in which the portion of the header of the data of the dependent information disk subunit is placed. Like the information, the data length of a single information field for the disk subunit, an attribute, a version of the disk subunit, the number of media types of support, and the data of media types of support are placed. As for the data of the medium type of support, as much data of the type of support means as indicated by the number of types of support means are placed. In the media type data, the details of the media format are indicated. In the case of the present example, it is known from the data that the device is a disk device that uses a disk has a format of an MD (mini disk) as the medium. In addition, a format of a data structure of a state instruction has a TAPE REPRODUCTION FORMAT to ask the required tape playback format after the subunit type decision if the determined type is tape shown in FIGURE 33. In this instruction, the data of the tape playback format is placed er. the operation code, and a specific value (here FF) is placed in the operands. And the format of a response for this status statement is shown in FIGURE 34. In this response, a media type data format parameter is placed in the area of the operands. The response on this occasion is indicated by one of the response types already shown in FIGURE ÍS1. To be specific, one response for a state instruction in the AV / C instruction is one of "NOT IMPLEMENTED", "REJECTED", "IN TRANSACTION" and "STABLE". In the case of a DVCR that has a D-VHS format corresponding to the AV / C instruction, the response does not become "NOT IMPLEMENTED" which is a response that disables the response to transmit the state instruction. Depending on the state of the device this time, the response becomes one of "REJECTED", "IN TRANSITION" and "STABLE". By judging the response to be other than "NOT IMPLEMENTED", the device is known to be a DVCR that has a D-VHS format. In the case of a tape device of a different format (such as a DVCR called standard DV), a status instruction of the TAPE PLAYBACK FORMAT is not implemented in the AV / C instruction, and consequently the response is made " NOT IMP EMENTED "so that the answer is impossible. When a network system has been formed by connecting devices controlled by the AV / C instruction to bus 1, it is possible to know details of the types, such as types and media formats, of the devices, without previously knowing which protocols devices are connected to. the network corresponding to, by conducting the process described hereinafter with reference to the present embodiment. It is possible to execute functions that can be executed only by devices that have specific media formats connected to the network, without user operation to establish the type of device and so on. After the types and other devices have been considered, it is necessary in some cases to collect detailed data concerning the devices. If altered devices are considered to exist in those devices by comparison with previously stored data, then only the data concerning the altered device is read. As a result, the load and processing time required to collect data concerning the devices connected to the network can be reduced. In the embodiment described above, the subunit type of the use of the subunit information instruction is first asked to determine whether a device connected to the network corresponds to an AV / C instruction. However, the protocol and series of instructions used by the device connected to the network can be ascertained by a different process. For example, a node (unit) connected to the network can be determined from the configuration data of the ROM if the device corresponds to the AV / C instruction. In other words, the data concerning the unit attributes of the ROM configuration prescribed by, for example, IEEE 1212 has a data configuration of a format shown in FIGURE 33. By a combination of special unit data id and SW version unit data included, in the data concerning the unit attributes, the corresponding instruction protocol are determined as shown in FIGURE 34. To be specific, it is known from these data that, for example, the instruction AV / C standard standardized by 1394TA, common application language standard (CAL) standardized by 1394TA, European Home System (EHS) standardized by 1394TA, and ANSI standard conformed to protocol and instruction series. When it is known from the correspondence between the data of the unit ID and data of the unit SW version in the protocol and series of instructions correspond to the instruction AV / C, the details of the unit can be queried. Further, after considering the protocol and series of instructions corresponding to the AV / C instruction from the correspondence shown in FIGURE 34, the process of step S12 and subsequent steps of the flow chart shown in FIGUFA 21, that is, the process of sending the statement of subunit status and subsequent processes can be executed. Furthermore, in the case where it is determined from the data difference whether the connected devices correspond to the AV / C instruction and in the decision of the connected device it is considered to correspond to the AV / C instruction, the type of detailed subunit and the format of the you can ask. For example, as shown in FIGURE 35, a code value of the CTS instruction is determined. It can be determined whether the connected device corresponds to the AV / C instruction on the basis of the code value of the CTS instruction. The code value of the CTS instruction is placed in a 4-bit section (a portion represented as 0000) located in the header of the FCP frame shown in FIGURE 18. In this case, when the code value of the CTS instruction is "0000", it is known that the connected device corresponds to the instruction AV / C. In addition, each data of the ROM configuration described by the IEEE 1212 is provided with a key ID as shown in FIGURE 36. By reading the data of the model ID included in the key ID, the details such as the type of the device they can be considered directly. Furthermore, in the embodiment described above, the process is carried out when the IRD 100 connected to the 1 collects data from devices included in the network formed by the 1. However, as a matter of the course, the present invention can also be applied to the case where any device collects data on the network. In addition, in the embodiment described above, the type of process discrimination device shown in the flow diagram of FIGURE 21 is carried out and after the data collection process of the device shown in the flow diagram of FIGURE 22 is carried out. Nothing is done after the discrimination process of the type of device, but when the data specifies the device connected to the network (as a unique ID node) is detected, the data collection process of the device shown in the flow diagram of FIGURE 22 can be carried out. In addition, in the modality described above, the case of the network formed by the bus of the 1394 IEEE scheme has been described. However, the present invention can also be applied to the case where the data concerning devices are collected in a different network configuration.

Claims (14)

1. A method for recognizing the network connection for recognizing a device connected to a predetermined network, consisting of: a step for recognizing the device to recognize a device connected to the network; a step of acquiring predetermined data data acquired from the recognition device; and a comparative comparison step of predetermined data obtained from the recognized device with previously predetermined data collected and stored, wherein when in the comparison step of predetermined data obtained from the recognition device it has coincided with the previously predetermined data collected and stored , the data concerning a corresponding device for stored predetermined data is used as data concerning the recognition device.

2. The method for recognition for network connection according to claim 1, wherein the predetermined data has an identifier capable of identifying each device individually.

3. The method for recognition for the connection of the network according to claim 1 which consists of: a step for the collection of data collection data concerning the device when in a comparison step of predetermined data obtained from the device of recognition has not coincided with the previously predetermined data collected and stored.

4. The method for recognition for the network connection according to claim 3 wherein the step for data collection consists of: a step of sending a request instruction to send an instruction to ask the unit type or type of subunit for the device; and a discrimination step of discriminating the type of unit or the type of subunit of the device based on the response of the device.

5. The method for recognition for the network connection according to claim 4 wherein the data collection step further consists of: a type corresponding to the instruction that sends the step of sending an instruction corresponding to the discriminated type; and a type of device that determines the step to determine the type of device based on the response obtained by the corresponding type of instruction sent in the step. The method for recognition for the network connection according to claim 1, wherein the step of recognizing the device to recognize a device connected to the network is carried out when a bus line forming the network is Restore. The method for recognition for network connection according to claim 1, which consists of: the data erasing step of erasing predetermined data stored when the previously predetermined data collected and stored does not match any of the data predetermined ones obtained from the recognition device. The method for recognition for network connection according to claim 1, comprising: the step of deleting data from erasing data concerning a corresponding device for stored predetermined data when the previously predetermined data collected and stored they do not match any of the predetermined data obtained from the recognition device. 9. A terminal device for the network connection connected to a predetermined network, comprising: a storage section for storing data concerning a device connected through the network; and a control section response to recognize a device connected through the network, to compare predetermined data transmitted from the device with data stored in the storage section, causing the data concerning the devices to incur no match in the comparison to be transmitted, and that causes the stored data of the storage section to be registered. 10. A terminal device for the network connection connected to a predetermined network, comprising: the recognition means device for recognizing a device connected to the network; the data of acquisition means to obtain predetermined data from the recognition device; and the comparison means for comparing the predetermined data obtained from the recognition device with previously predetermined data collected and stored, wherein when in the means of comparison of predetermined data obtained from the recognition device they have coincidence with the previously predetermined data collected and stored, the data concerning a corresponding device for the stored predetermined data is used as data concerning the recognition device. The terminal device for the network connection according to claim 10, wherein the predetermined data has an identifier capable of identifying each of the devices individually. The terminal device for the connection of the network according to claim 10, comprising: the instruction of the output means for generating and outputting a first instruction to ask for a device connected via the network about a type of unit or a type of subunit; and the means of discrimination to receive a response for the first instruction, and the discrimination of a unit type or subunit type of the device based on the response. 13. The terminal device for connecting the network according to claim 12, consisting of: the output instruction means for generating and outputting a second instruction corresponding to the type of unit or subunit type of the device; receiving means for receiving a response for the second instruction of the device 14. The terminal device for connecting the network according to claim 10, wherein the means for recognizing the device conducts the process for recognizing a connected device by means of the network when the means of recognition of the device has detected that a bus line formed in the network is restored.