JP2001069164A - Method for managing connection in equipment linked by digital interface and instruction structure therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for managing connection in equipment linked by digital interface and an instruction structure therefor. SOLUTION: Concerning the method for managing connection in equipment in a network system connecting equipment to transmit information and equipment, to which the information is transmitted, through a prescribed digital interface on the basis of a prescribed data transmission standard, this method is provided with a stage for reporting a state change in the connection to the other equipment when such a change occurs in one of equipment, to which the connection is established, and the equipment on the opposite side can deal with the change and can efficiently manage the state of connection by informing the various state changes of the connection related to the transmission flow of information during real time information transmission in the equipment linked by the prescribed digital interface standard.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to the field of information transmission control, and more particularly, to a connection management method capable of notifying a user of a change in a connection management state between devices connected to a digital interface, and a command structure therefor.

[0002]

2. Description of the Related Art Home or industrial equipment is provided with a predetermined digital interface standard, such as the IEEE (The Institute of
Electrical and Electronics Engineers, Inc) 1394
Real-time information is transmitted and transmitted while being interconnected by a standard bus. For example, digital television (Digital Television, DTV), digital video camcorders, set-top boxes (set-t
When devices such as op boxes and STBs are interconnected to form a network, real-time information such as video and audio information is transmitted between these devices.

FIG. 1 is a schematic diagram showing a network system connected by a general IEEE 1394 bus, in which real-time information is output from a virtual output plug of any one device and is input to another device. Input to the plug, such a connection is conceptual and not a physical connection.

A source device (here, STB) 100 having an output plug 101 for transmitting information has an output plug 1
01 for controlling the flow of information output through the output plug control register (output plug control register:
oPCR) 111, and a sink device (here, a DTV) 200 that also has an input plug 201 and transmits information, has an input plug control for controlling the flow of information input to the input plug 201. Register (input plug contro
l register: iPCR) 211. The control device having the controller 300 may be one of the STB 100 and the DTV 200, and may be another third device, the oPCR 111 and the iPCR
It controls the control value of 211 and establishes or breaks a connection so that information is transmitted.

Accordingly, real-time information is transmitted from the output plug 101 to the input plug 201, and at this time, relevant control information is written into the oPCR 111 and iPCR 211 corresponding to each plug, and is written into the oPCR 111 and iPCR 211 by the controller 300. The flow of the real-time information is controlled by reading the stored value or writing the control value therein.

Here, the control values written in the oPCR 111 and the iPCR 211 will be described with reference to FIGS. 2 and 3.

First, the 32-bit oPCR1 shown in FIG.
The definition in the format of 11 is as follows, and the numbers indicate the allocated bits. Online (on-line) indicates whether the corresponding output plug is online (value of "1") or offline (value of "0"). The broadcast connection counter indicates whether a broadcast-out connection exists in the output plug ("1" value) or does not exist ("0" value). PTP connection counter (point-to-poin
t connection counter) indicates the number of PTP connections present in the output plug. The channel number is the data flow when the output plug is isochronous when the output plug is activated
Indicates a channel number that can be used to transmit (isochronous data flow). Data rate
(data rate) indicates a transmission rate (also referred to as a bit rate) used by the output plug to transmit an isochronous packet of an isochronous data flow when the output plug is enabled. The overhead ID is the payload of the isochronous packet.
oad) indicates the required bandwidth in addition to the required bandwidth. The payload indicates the maximum data of the isochronous data output from the output plug when the output plug is valid.

[0008] The definition according to the format of the 32-bit iPCR 211 shown in FIG. 3 is as follows, and the numbers indicate assigned bits. The online bit indicates whether the corresponding input plug is online ("1") or offline ("
The broadcast connection counter indicates whether a broadcast-in connection exists (a value of "1") or does not exist (a value of "0") in the input plug. Indicates the number of PTP connections present on the input plug, and channel number indicates the channel number used by the input plug to receive the isochronous data stream.

[0009] Accordingly, a control device having a controller is assigned a channel value to be used and assigned to each oPCR1.
11 and the channel values assigned to the iPCR 211 are written in the channel numbers shown in FIGS. 2 and 3, and other control values (on-line bit values, connection counter values...) Are written to the oPCR 111 and the iPCR 211, respectively. The device and the sink device transmit or stop information according to this value.

As shown in FIGS. 2 and 3, there are two types of connections for transmitting information: a PTP connection and a broadcast connection. In the case of a PTP connection, only the control device that has set the connection establishes the connection. It can be broken.

Therefore, when the third control device sets the PTP connection, the set two devices (the source device and the sink device) should continue transmitting even if they do not want to transmit any more information. Even if you do not want to receive it, you should receive it.

In order to inform such a point, the AV / C CTS (a
udio-video / control command transaction sets) defines a new control command, and presents an algorithm to notify the control device or connected partner device when it does not want to receive or send any more information. Have been.

That is, when a change occurs in a device that transmits real-time information or a device that transmits the information, a command for notifying the change is defined.
Informs whether each input plug wants to be input, and whether each output plug wants to output, and also informs when the format of the signal output from the output plug changes. be able to.

However, other factors controlling the information flow as commands of this AV / C CTS, such as changes in bandwidth and changes in information as to whether or not some equipment is connected to the connection, are signaled. There were no problems.

[0015]

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems. It is an object of the present invention to provide various connections related to the flow of information transmission during transmission of real-time information between devices connected according to a predetermined digital interface standard. An object of the present invention is to provide a connection management method for notifying a state change (data transmission and reception states, whether data processing is possible, data bandwidth).

Another object of the present invention is to generate a connection management command between devices connected according to a predetermined digital interface standard, and transmit various connection state changes related to information transmission flow in response to the connection management command. It is to provide a connection management method to be performed.

It is still another object of the present invention to provide a connection management command structure indicating various connection state changes related to information transmission flow during transmission of real-time information between two devices connected according to a predetermined digital interface standard. To provide.

[0018]

In order to achieve the above object, a connection management method according to the present invention comprises at least one device for transmitting information according to a predetermined data transmission standard and one or more devices for transmitting information. In a method for managing a connection between the devices in a network system in which the devices are connected by a predetermined digital interface, if any one of the devices for which the connection has been established causes a change in the state of the connection, this is changed. The step of notifying the device of the above.

According to another aspect of the present invention, there is provided a connection management method for connecting a device for transmitting information according to a predetermined data transmission standard connected to a predetermined digital interface with a device for transmitting information. And transmitting a connection management command for controlling the connection management state, and controlling the connection when a response to the change in the connection management state is received by the connection management command. Features.

According to another aspect of the present invention, there is provided a connection management command structure, wherein a device for transmitting information according to a predetermined data transmission standard and a device for transmitting information are connected by a predetermined digital interface. In a command structure for notifying a user of a change in the state of a connection between devices having a connection established in a network system, an output plug control register built in the device transmitting the information, or the information is transmitted. It is characterized by having a connection register type indicating whether the input plug control register is built in the device and identification information of an input / output plug for which a connection is set.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a preferred embodiment of a method for managing connections between devices connected by a digital interface according to the present invention and an instruction structure therefor will be described with reference to the accompanying drawings.

The present invention is based on the IEC 61883 standard (Specificatio) for data transmission between devices using the IEEE 1394 standard.
n of Digital Interface for Electronic Audio / Video
Equipment, Part 1, December 1995, HD Digital VCR
Conference) output plug control register (o
When a change occurs in the control value of the input plug control register (iPCR) and the input plug control register (iPCR), a connection management command structure for notifying the change to the control device or the connected counterpart device is defined as shown in FIG. And the instruction format defined by the AV / C CTS standard.

In FIG. 4, an operation code (opcode) name is defined as connection management, and an operand (operand) is defined.
[0]) is 1 byte, and when looking at the contents of the 1-byte field, the msb (most significant bit) is a 1-bit connection register type (I / O) indicating iPCR or oPCR, and the next 1 bit is Reserved, the remaining 6 bits contain plug identification information indicating the number of the corresponding plug for which the connection has been set.

After operand [0], another operand (operan
By adding d [1] -operand [4]), various information related to connection management can be transmitted.

The bit fields (online, broadcast crossing counter, PTP connection counter, channel number, data rate, overhead) can be set according to the format of the oPCR shown in FIG.
ID, payload) and specify bit fields (online, broadcast connection counter,
Unnecessary response transmission can be prevented by designating only a part of PTP connection counter and channel number).

Therefore, when it is desired to know a change in a desired bit field among the 32 bits of the oPCR or iPCR, the control device operates the operand (operand [1] -operand) shown in FIG.
Use [4]) to change the bit at the position of the corresponding bit field to "
The operand set to the source device or the sink device may be transmitted using a notify command by setting to 1 ". For example, if only the online bit field is of interest, only that bit may be designated. That is, if the bit position corresponding to online is b0, only the bit position corresponding to b0 in the operand (eg, operand [1]) can be set to "1" and the remaining bits can be set to "0" for transmission.

In the connection management command structure shown in FIG. 4, an operand (operand [n]) as to whether or not the connection is private, in addition to the factors related to the connection management format shown in FIGS. ) Can be added.

Therefore, any one device (control device) connected according to IEEE 1394 specifies an output plug or an input plug in another device (source device or sink device) in the connection management command shown in FIG. Although transmitted, this connection management command can be defined as a new command of the notification command defined in AV / CCTS. For reference, there are various types of AV / C CTS commands.Among them, if you want to know the status that changes to the future, if you send the notification command by the controller, the device to which the notification command was transmitted (both target and Responds to the current state, and later (ta)
rget) is a command that responds to the controller when the status changes again.

In the present invention, if the connection management notification command shown in FIG. 4 is transmitted, the device to which the notification command has been transmitted causes a change in any one bit in the plug control register designated by the connection management notification command. In this case, this change is retransmitted as a response to the device that sent the notification instruction. The device that has received the response reads the information on the corresponding plug control register of the partner device, checks which bit field has changed, and takes appropriate action based on the changed bit field.

That is, if the device to which the notification command is transmitted is a source device having an oPCR, if the online bit field of the various bit fields of the oPCR changes from "1" to "0" first, this source device is The control device disconnects the connection with the source device because it is interpreted that no more data is output or that no output is desired. Conversely, when the online bit changes from "0" to "1", it is considered that the source device wants to output, so the control device establishes the connection with the source device. For example, when the DTV (source device) terminates the regular broadcast program and outputs a no-signal, the control device disconnects the connection with the DTV.

When the value of the broadcast connection counter or the value of the PTP connection counter in the bit field of the oPCR changes, another device is overlaid on the predetermined connection, or the overlaid connection is disconnected. Indicates that the connection state has changed. If the connection is set by the user (source device = control device), the value of the PTP connection counter was "1".
If it changes to 2 ", it can be considered that the information output from this source device is transmitted to another device.
If the connection is set as a private connection, the user can be informed that other people are also viewing the information that he or she is watching, so that the user can appropriately deal with this.

When the value of the payload indicating the bandwidth of the output information in the bit field of the oPCR changes, the control device changes the output information bandwidth of the source device to the inputtable bandwidth of the sink device. And take appropriate action based on that. For example, if the bandwidth of the output information transmitted by the source device is larger than the bandwidth that can be accepted and processed by the sink device, the connection of the sink device may be cut off so that no more information is received.

Similarly, the device to which the notification command has been transmitted is the iPCR
The online bit is "0" for a sink device with
When the state of the sink device changes from "1" to "1", the control device sets the connection of the sink device because it is considered that the sink device wants input. Can be cut off. For example, when a video cassette recorder (sink device) completes all the recordable areas of a tape and enters a non-signal area, the user can immediately notify the user of this and pull out or replace the tape. Can be.

FIG. 5 is a flow chart showing one embodiment of the connection management method according to the present invention. The connection management method is performed by a control device having a controller.

The connection between the source device and the sink device is established according to the procedure defined in IEC61883 (step S101). At this time, the connection may be a PTP connection or a broadcast connection.

The connection management notification command is sent to the source device and / or the sink device (S102).
After the current state is transmitted from the device to which the notification command has been transmitted, the system waits until a notification response to the connection management change comes (step S103), and changes in the bit field of the corresponding plug control register of the device to which the notification command has been transmitted. Is received (step S104).

When a response is received in step S104, a change in the online bit field is checked first (S1).
05 stage). If the online bit in the bit field of the corresponding plug control register is changed to "0" in step S105, the connection is disconnected (step S106).

If the on-line bit is not changed to "0" in step S105, when the private connection is set, the broadcast connection counter or PT in the bit field of the corresponding plug control register is set.
Check whether the value of the P counter has changed (S1
(Step 07), if there is a change, the user is warned of an overlay connection, and appropriate measures can be taken (S
108 stages).

If the value of the connection counter has not changed in step S107, it is checked whether the payload has been changed in the bit field of the corresponding plug control register (step S109), and if the payload has been changed, the bandwidth is adjusted. (Step S110). Check whether the adjusted bandwidth is a bandwidth that can be accommodated by the sink device that inputs information (step S111), and disconnect the connection of the sink device if the adjusted bandwidth is too wide (step S112).
Otherwise, the connection management command is transmitted in S10.
Proceed in two stages.

[0040]

According to the present invention, when any one of the devices connected by the digital interface does not want any more output and input, the connection can be disconnected, so that the connection is set up uselessly. The bandwidth is not wasted, and only the necessary bandwidth can be used as needed, so that the efficiency of the bandwidth use can be increased.

According to the present invention, various status changes (data transmission / reception status, whether data processing is possible or not) which can occur in information processing of the partner device can be immediately recognized, so that the user can generate the status inside the connected device. It is possible to quickly grasp the changed state and deal with it.

In addition, the present invention relates not only to information as to whether a source device desires to transmit information, but also to a change in the number of sink devices connected to the source device and a change in the bandwidth that the source device can output. Can be notified of a change in the bandwidth that can be input by the sink device. For example, when the number of sink devices connected to the source device increases, such a change is notified to the user, and if the user does not want to connect another device further, the connection of the other device is not allowed. Thus, the state of the connection can be managed efficiently.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a network system connected by a general IEEE 1394 bus.

FIG. 2 is a diagram showing a format of an output plug control register shown in FIG. 1;

FIG. 3 is a diagram showing a format of an input plug control register shown in FIG. 1;

FIG. 4 is a diagram showing a connection management command structure according to the present invention.

FIG. 5 is a flowchart of a connection management method according to an embodiment of the present invention.

Claims (24)

[Claims] 1. A network system in which one or more devices transmitting information according to a predetermined data transmission standard and one or more devices transmitting information are connected by a predetermined digital interface, and manages connections between the devices. (A) any one of the devices for which the connection has been established;
A connection management method including a step of notifying a change in the state of the connection to another device at all times. 2. The connection management method according to claim 1, wherein the other device is a device that has transmitted a connection management notification command. 3. The connection management method according to claim 2, wherein said another device is a control device or a device on the other side of the connection. 4. The method according to claim 1, wherein the predetermined digital interface is an IE.
EE 1394 standard, the prescribed data transmission standard is IEC
The connection management method according to claim 1, wherein the connection management method is 61883 standard. 5. In the step (a), any one of a bit field of an output plug control register built in a device transmitting the information and / or a bit field of an input plug control register built in a device transmitting the information is used. If only one bit field changes, the change is notified to another device, and the output plug control register and the input plug control register are connection control registers defined in IEC 61883 standard. 2. The connection management method according to 1. 6. The connection according to claim 1, wherein in the step (a), when a bit field indicating online or offline changes in a device transmitting the information, the bit field is notified to another device. Management method. 7. The method as claimed in claim 1, wherein in step (a), when a bit field indicating whether the information is transmitted is online or offline, the information is notified to another device. Connection management method. 8. The method of claim 1, wherein in step (a), when a bandwidth of output information from a device transmitting the information changes and a payload bit field changes, the change is notified to another device. Connection management method described in 1. 9. In the step (a), when a connection counter bit field changes according to a change in the number of devices transmitting information from the device transmitting the information,
2. The connection management method according to claim 1, wherein this is notified to another device. 10. The step (a) includes: (a1) If the number of devices transmitting the information increases from the device transmitting the information, information other than the device receiving the original information is transmitted. 10. The connection management method according to claim 9, further comprising a step of suppressing transmission of information to another device. (A) establishing a connection between a device that transmits information according to a predetermined data transmission standard connected by a predetermined digital interface and a device that transmits information; and (b) determining a connection management state. A connection management method, comprising: transmitting a connection management command to be controlled; and (c) controlling the connection when a response to the change in the connection management state is received by the connection management command. 12. The predetermined digital interface is
IEEE 1394 standard, wherein the predetermined data transmission standard is IEC
The connection management method according to claim 11, wherein the connection management method is 61883 standard. 13. The connection management method according to claim 11, wherein in the step (b), the connection management command follows an AV / CCTS standard notification command format. 14. In the step (c), the change of the connection management state may be any one of a bit field of an input plug control register and / or an output plug control register of a connection control register defined in IEC 61883 standard. The connection management method according to claim 11, wherein a response is received even if only one bit field changes. 15. In the step (c), when the response indicates that a bit field indicating online or offline is changed in a device transmitting the information, the connection is disconnected or established. 1
2. The connection management method according to 1. 16. In the step (c), if the response indicates that a bit field indicating online or offline is changed in a device to which the information is transmitted, the connection is disconnected or established. Item 12. The connection management method according to Item 11. 17. In the step (c), if the response indicates a change in the payload bit field due to a change in the bandwidth of the output information from the device transmitting the information, the bandwidth of the output information is changed by the device transmitting the information. The connection management method according to claim 11, wherein the connection is disconnected or established depending on whether the width can be accommodated. 18. In the step (c), if the response indicates a change in a connection counter bit field due to a change in the number of devices transmitting the information in the device transmitting the information, the information is transmitted. The connection management method according to claim 11, wherein the connection of the device is disconnected or established. 19. The step (c) includes: (c1) when the number of devices transmitting the information in the device transmitting the information is changed, and the original information is transmitted when the personal connection is established. The method of claim 11, further comprising the step of notifying a user to suppress transmission of information to other devices than the device. 20. Use of a change in the state of a connection between devices that have been connected in a network system in which a device that transmits information according to a predetermined data transmission standard and a device that transmits information according to a predetermined digital interface are connected. In the instruction structure for notifying the user, a connection register type indicating whether the output plug control register is built in the device transmitting the information or the input control register is built in the device transmitting the information. A connection management command structure, characterized by having identification information of an input / output plug to which a connection is set. 21. The connection management command is AV / CCTS.
The connection management command structure according to claim 20, wherein the connection management command structure conforms to a standard format. 22. The predetermined digital interface
IEEE 1394 standard, wherein the predetermined data transmission standard is IEC
The connection management command structure according to claim 20, wherein the connection management command structure is 61883 standard. 23. The connection management command according to claim 20, wherein an operand for designating only a part of a bit field of the output plug control register and / or the input plug control register is added. Construction. 24. The connection management command structure according to claim 20, wherein an operand indicating whether or not the connection is dedicated to an individual is added.