JP2001308872A - Data processing unit, medium and information aggregate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a data processing unit that calculates a node ID of a transmitter side by physically deciding a device of a transmission source and a connection port of a reception destination, so as to recognize changes in a transmission stream at its reception side. SOLUTION: The data processing unit 900, that consists of an IEEE1394 serial bus and receives at least digital data on a network, recognizes whether it receives the transmission stream sent from a node connected to a specific connection port, even after re-configuration of the network resulting from bus reset of the IEEE 1394 serial bus, when the processing unit receives the transmission stream sent from the node connected to the specific connection port.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a data processing apparatus, and more particularly to a data processing apparatus used in a system for transmitting and receiving data in packet units via a serial bus conforming to the IEEE 1394 standard.

[0002]

2. Description of the Related Art In recent AV systems and the like, many electronic devices are interconnected to construct a system. For example, in an AV system, a TV, a video tape recorder, a digital video camera, and the like are connected between input / output terminals to form an AV system.

Therefore, in recent years, standards suitable for data communication in the multimedia age have been proposed.
There is an IEEE 1394 high performance serial bus standard (hereinafter, IEEE 1394 standard), and an environment has been developed so that high-speed, large-capacity communication can be freely performed.

[0004] The transfer mode conforming to the IEEE 1394 standard includes an "asynchronous (asynchronous) transfer mode".
And "isochronous (synchronous) transfer mode", and both perform data transfer in packet units.

In the asynchronous transfer mode, reading (reading), writing (writing), and locking can be performed on memories and registers of other nodes. In addition, the isochronous transfer mode is a mode in which a fixed amount of packets are transmitted and received every 125 μsec, and is suitable for transfer of video and audio because high-speed processing is possible.

FIG. 4 shows the isochronous packet format. As shown in FIG. 4, this packet format is a packet composed of a 32-bit data string, and includes a header part and a data part. The header portion includes a data length (data_length), a tag (tag), a transaction code (tcode),
There is a synchronization code (sy), which is indispensable in the isochronous packet format, but is not important for the present invention, so that the description is omitted.

Next, the channel field must specify the isochronous channel number of the packet. Instead of forwarding to a specific device (node), use the channel number to transmit to the entire bus.
Channel numbers 0 to 63 can be used for assignment. IEEE 139 such as current digital video cameras
Many of the four devices use the channel number 63 as a default value. At the beginning of the data field of the isochronous packet shown in FIG. 4, a header indicating a data attribute is CIP (Common Isoch).
(roublePacket) header is inserted.

FIG. 5 shows the format of the CIP header. SID (Source node ID) is the ID of the node transmitting the packet. Hereinafter, DBS
(Data Block Size), FN (Func
Tion Number), QPC (Quadlet)
Padding Count), SPH (Source)
Packet Header), Rsv (Reserv)
ed), DBC (Data Block Count)
t), FMT (Format ID), FDF (For
mat Dependent Field) is not important in the present invention and will not be described.

The feature of IEEE 1394 is plug-and-play. Even when a new device is added or removed, a node ID or the like does not need to be set each time, and a node ID is automatically assigned. Node ID
The assignment is completed when a bus reset occurs and the IEEE 1394 device issues a self-ID. The network is rebuilt by the occurrence of the bus reset,
The node ID assigned to each device changes automatically.

First, when a bus reset occurs, the bus reset signal changes all nodes to a special state and clears all topology information. Thereafter, tree identification is performed to determine the parent-child relationship between the nodes. Tree identification converts the entire network topology into a single tree, as illustrated in FIG. Here, port numbers are assigned to the ports of each node. After tree identification, the root node is a node in which the vertices of the tree structure, that is, all the connection destinations of the ports are child nodes. A node with only one connection is called a leaf, and two or more connected nodes are called branches.

Next, self-identification is performed, and each node notifies the nodes on the bus of the basic information as a self-ID packet. FIG. 7 shows the format of the self-ID packet. phy_ID (physical_ID) indicates the physical node identifier of the transmitting side of this packet. Also, p
0... P26 indicate the state of the port, and are “connected to the child node”, “connected to the parent node”, “other Ps”.
There are four states of “not connected to HY” and “not present on this PHY”. In addition, L (link_a
active), gap_cnt (gap_count
t), sp (PHY_SPEED), del (PHY_
DELAY), c (CONTENDER), pwr (P
OWER_CLASS), i (initialized_r)
Eset) and m (more_packets) are also essential in the self-ID packet format, but they are not important for the present invention, and thus description thereof is omitted. When there are four or more ports, # 1, # 2, and # 3 are continuously transmitted according to the number of ports.

A self-ID is issued from a port having the smallest port number in a child node connected to the root. If the node is a branch, the self-ID is issued from the node connected to the smallest port number among the child nodes of the branch. The port having the smallest port number is defined as p0... Of the self-ID packet shown in FIG.
pn... ports having the smallest n in p26. Self-
The ID is counted up each time it is issued.

For example, assuming that the connection is as shown in FIG. 6, first, a node 102 having the smallest port number # 1 among the child nodes connected to the root node 101 receives a self-ID (node ID = # 0) is issued.

Next, the port number # 2 of the undetermined child node
Is a branch, the node 104 connected to the smallest port number # 2 among the undetermined child nodes connected to the node 103 issues a self-ID (node ID = # 1). .

Next, the smallest port # 3 among the undetermined child nodes
Is connected to the self-ID (node ID).
= # 2). Subsequently, the node 103 (node I
D = # 3) and finally the root node 101 (node ID =
# 4) issues a self-ID. Thereafter, when the bus is idle, normal arbitration can be performed.

[0016]

According to the IEEE 1394 standard, a plurality of nodes cannot access a single bus at the same time. Therefore, in order to transmit a transmission stream, arbitration is performed and the root node is permitted to use the bus. You need to get At the time of arbitration, the node which first delivers the request signal to the route obtains the right to use the bus.

[0017] Two IEEE 1394 devices transmitting and receiving in a certain network have the same channel number and are trying to transmit a transmission stream.
When an E1394 device is connected, a bus reset occurs and the network is reconfigured. Next, each IEEE 1394 device that attempts to transmit the transmission stream performs arbitration. Depending on the winner of the arbitration, the transmission stream flows from a device different from the transmission source before the bus reset. If the receiving side is recording, there arises a problem that unnecessary data is recorded due to the occurrence of a bus reset.

As shown in the flowchart of FIG. 8, when there are a plurality of devices transmitting a transmission stream (S100), a bus reset occurs (S110 to S110).
130), arbitration (S140) is performed again, and the right to transmit the transmission stream to the winner (S15).
0) is given. Here, there is a problem that the transmission source may be switched before and after the bus reset occurs.

An isochronous transfer packet has information of a channel number and a source node ID assigned to data.

However, since the node ID of each device is automatically assigned, the receiving side determines whether the transmission stream is from a device that the user actually wants to receive or whether the transmission stream is transmitted by another device. Can not.

The present invention has been made in view of the above-described problem, and detects a transmission-side node ID by physically determining a source device and a connection port of a reception destination, and detects a node ID after a bus reset. It is an object of the present invention to obtain a data processing device, a medium, and an information aggregate capable of recognizing a change in a transmission stream on a receiving side.

[0022]

In order to solve the above-mentioned problems, a first invention (corresponding to claim 1) is based on the IEEE 13 standard.
In a data processing device that receives at least digital data on a network constructed by a 94 serial bus, when a transmission stream transmitted by a node connected to a specific connection port is received, the IEEE13.
A data processing device for recognizing whether or not a transmission stream transmitted by a node connected to the specific connection port has been received even after reconfiguration of a network by a bus reset of a 94 serial bus.

The second invention (corresponding to claim 2)
Calculates a node ID of a node connected to the specific connection port by using a self-identification packet.
A calculating means, and a node ID for comparing and managing the node ID calculated by the node ID calculating means and the node ID given to the transmission stream received by the data processing device.
A comparison management means, and using the information managed by the node ID comparison management means, even after the network is reconfigured by a bus reset of the IEEE 1394 serial bus,
The present invention is characterized by recognizing whether a node connected to the specific connection port has received a transmission stream to be transmitted.

The third invention (corresponding to claim 3)
Receives the transmission stream transmitted by the node connected to the specific connection port while the IEEE 1
When the reconfiguration of the network is performed by resetting the 394 serial bus, the node ID calculation unit calculates a new node ID of the node connected to the specific connection port, and the node ID comparison management unit The data processing device compares the new node ID calculated by the node ID calculation means with the node ID assigned to the transmission stream received after the data processing device reconfigures the network. , Said IEEE13
Even after the reconfiguration of the network by the bus reset of the 94 serial bus, it is recognized that the transmission stream transmitted by the node connected to the specific connection port has been received, and when the comparison result does not match, the data processing device Is the I
The present invention is characterized in that, after the network is reconfigured by the bus reset of the IEEE 1394 serial bus, it is recognized that the transmission stream transmitted by the node connected to the specific connection port has not been received.

Further, the fourth invention (corresponding to claim 4)
After the data processing device reconfigures the network by resetting the IEEE 1394 serial bus,
When the node connected to the specific connection port recognizes that the transmission stream to be transmitted has not been received, there is provided a notifying unit for notifying the recognition to the outside.

The fifth invention (corresponding to claim 5)
The specific connection port has the largest port number among the ports of the data processing device, and has the largest port number of the ports of the node that transmits the transmission stream. The present invention is characterized in that the present invention is used in connection with an object.

Further, a sixth aspect of the present invention (corresponding to claim 6)
Is an isochronous (synchronous) transfer mode according to the IEEE 1394 standard.

Further, a seventh aspect of the present invention (corresponding to claim 7)
Is a medium that carries a program and / or data for causing a computer to execute all or a part of the functions of all or part of the present invention, and is a medium that can be processed by a computer. is there.

An eighth aspect of the present invention (corresponding to claim 8)
Is an information aggregate, which is a program and / or data for causing a computer to execute all or a part of the functions of all or part of the present invention.

According to the data processing apparatus of the present invention as described above, two devices in a certain network
When data is being transmitted / received through the 94 serial bus, when a device that is transmitting the transmission stream with the same channel number exists in the network or when the device is connected, the transmission stream of the IEEE 1394 bus is switched due to the occurrence of a bus reset. The receiving side can also provide a data processing device capable of recognizing it.

Further, according to the present invention as described above, the data processing apparatus has at least one or more 1394 ports on both the transmission side and the reception side, and connects the connection ports having the maximum port numbers.

[0032]

Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 9 is a configuration diagram of an IEEE1394 device in an embodiment of the data processing apparatus of the present invention. As shown in the figure, in the IEEE 1394 device 900, the node ID calculation unit 910 is
A means for calculating a node ID of a node which is associated with a specific port of the EE1394 device and outputs to a specific port using a self-recognition packet (self-ID packet). The node ID calculated by the node ID calculation means 910 and the IE
This is a means for comparing and managing a node ID included in a transmission stream input to the EE1394 device 900. However, the transmission stream is transmitted in an isochronous (synchronous) mode.

FIG. 3 shows the IE in the present embodiment.
7 shows a flowchart of a general operation of the node ID calculation means 910 in the EE1394 device 900. However, as a precondition for the operation, as in the configuration example shown in FIG. 2 described above, the IEEE 1394 device 900 is connected to the IEEE 1394 device serving as the transmission side (target) via ports having the maximum port numbers. Shall be.

The IEEE 1394 device 900 on the receiving side is:
When the bus reset processing (S200 to S220) of the IEEE 1394 network in which the IEEE 1394 device 900 is included as a node ends and all the nodes belonging to the network have finished issuing the self-ID packets, the self-ID packets of the own node are set. See
The status of the port to which the target is connected and which has its own maximum port number is confirmed (S230). If the target node is the parent node, the value of the node ID of the receiving node is +1 (S240). If the target node is a child node, the value of the node ID of the receiving node is -1 (S250). The node ID calculating means can acquire the target node ID (S260). The acquired node ID is transferred to the node ID comparison management means 920. The node ID comparison management means 920 holds the calculated node ID.

FIG. 2 is a diagram exemplifying a state where four IEEE 1394 devices are connected. In the figure,
Reference numeral 201 denotes an IEEE device on the receiving side according to the embodiment of the present invention, and 202 denotes a transmitting side (target). Reference numeral 203 denotes an IEEE 139 which is a root node.
4 devices, 204 is an IEEE1 that is a leaf node
394 devices. However, among the four IEEE devices shown in the figure, the IEEE 1394 according to the embodiment of the present invention.
It is assumed that the device is only 201 and the others are conventional IEEE devices.

Next, FIG. 1 shows an IEEE 1394 device 201 of the present embodiment shown in FIG. 2 and a conventional IEEE 139 device.
4 is a flowchart showing a flow of an entire operation with four devices 202. However, in the flowchart shown in the figure, the steps of S301 to S302 and S307 to S308 are the same as those shown in FIG.
This is the operation of calculating the node ID of the target by the device.

Hereinafter, an IEEE 1394 device 201 and a conventional IEEE 1394 device will be described with reference to the flowchart of FIG.
The operation with the 394 device 202 will be described.

First, the IEEE 1394 device 201 on the receiving side and the IEEE 1394 device 202 on the transmitting side (target) are connected to each other by the ports having the maximum port numbers of the respective devices (S300). At this time, if it is assumed that a number larger than the connected port is not used, each of the above ports may not be a port having the largest port number existing in the IEEE 1394 device.

Next, when the receiving side and the transmitting side are both connected (rise up), a bus reset occurs, and the node ID is reassigned (S301). IE on the receiving side
The IEEE 1394 device 201 uses the node ID calculation means to transmit the IEEE 1394 device 202 on the transmission side (target).
Is calculated (S302). Further, the calculated node ID is stored in the node ID comparison management means (S303).

Subsequently, when the transmission stream flows to the IEEE 1394 device 201 (S304), the node ID comparison management means calculates the node ID assigned to the data of the transmission stream and the node ID calculated by itself. The node ID of the target calculated by the means 901 is compared each time, and this comparison information (for example, confirming that there is a transmission stream from the target) is managed and stored (S305). In this case, the target is IEEE
Since it is an E1394 device 202, its node ID is #
It is one.

Next, when a new device is connected to the IEEE 1394 network (S306), a bus reset subsequently occurs, and the node IDs of all the nodes connected to the IEEE 1394 bus are updated (S307).
The IEEE 1394 device 201 performs the above operation (S30
Similarly to 2), a new target node ID is calculated based on the self-ID of the user (S308). The node ID comparison management means includes a node ID assigned to the data of the transmission stream and a node ID held by itself.
The node ID of the target calculated by the D calculating unit 901 is compared each time, and the comparison information is managed and stored (S309). In this case, the IEEE 1394 device 20
Assuming that an IEEE 1394 device is newly connected to a port p1 different from the port to which the target is currently connected and node ID # 1 is assigned, the connection state of each IEEE 1394 device is as shown in FIG. Similarly, the IEEE 1394 device 203 is the root node, and the node ID is # 4. The target is I
Since the device is the EEE1394 device 202, the target node ID is # 2.

Subsequently, the IEEE 1394 device 201
Upon receiving the input of the transmission stream after the occurrence of the new bus reset (S310), the node ID comparison management unit compares the already calculated new node ID with the node ID included in the transmission stream after the bus reset, It is confirmed whether the stream is a transmission stream transmitted from the IEEE 1394 device 202 as the previous target (S311).

If the calculated node ID (# 2) is different from the node ID (# 1 or # 2) in the transmission stream (that is, the node ID in the transmission stream is # 1), the current IEEE 1394 device 201 It is possible to recognize that the received transmission stream is not the transmission stream from the IEEE 1394 device 202 as the previous target, that is, the transmission stream of the target has been replaced with the transmission stream of another device.

A notifying means 9 for notifying a recognition result, such as an IEEE 1394 device 901 shown in FIG.
When the configuration is provided, the user of the IEEE 1394 device or another IEEE 1394 device can know that the transmission stream from the target is not input, and in accordance with this, turns off the power of the connected IEEE 1394 device. Or by removing the device, and thus, processing such as reconfiguration of the network can be performed.

At this time, even when the transmission stream of the target is received due to the occurrence of the bus reset while the transmission stream of the device other than the target is being received, the IEEE 1394 device on the receiving side can recognize the change of the transmission source. .

In the above description, the data processing apparatus according to the embodiment of the present invention has been described. However, the present invention relates to all or some of the means of the data processing apparatus according to the above embodiment. A medium in which a program and / or data for causing a computer to execute some functions is readable by a computer, and the read program and / or data cooperates with the computer to execute the functions. May be realized as a medium for executing the program.

Further, the present invention is an information aggregate which is a program and / or data for causing a computer to execute all or a part of the functions of all or a part of the data processing apparatus of the above embodiment. Thus, it may be realized as an information aggregate that executes the functions in cooperation with the computer. However, in the above description, data includes a data structure, a data format, a type of data, and the like. The medium includes a recording medium such as a ROM, a transmission medium such as the Internet, and a transmission medium such as light, radio waves, and sound waves. Further, the carried medium includes, for example, a recording medium on which a program and / or data is recorded, a transmission medium for transmitting the program and / or data, and the like. In addition, the fact that it can be processed by a computer means, for example, a ROM
In the case of a recording medium such as, for example, it must be readable by a computer, and in the case of a transmission medium, the program and / or data to be transmitted must be able to be handled by the computer as a result of transmission. including. The information aggregate includes, for example, software such as programs and / or data.

[0049]

As described above, according to the data processing device of the present invention, it is possible to provide a data processing device that recognizes that the transmission source of the transmission stream does not change even after the bus reset.

[Brief description of the drawings]

FIG. 1 is a flowchart showing a series of flows in an embodiment of the present invention.

FIG. 2 shows an IEEE1394 according to an embodiment of the present invention.
Diagram showing an example of the connection state of devices

FIG. 3 is a flowchart showing processing of a target node ID calculating unit according to the embodiment of the present invention;

FIG. 4 is a diagram showing a packet format of isochronous transfer conforming to the IEEE 1394 standard;

FIG. 5 is a diagram showing a format of a CPI header added to an isochronous packet.

FIG. 6 is a diagram showing an example of a connection state of an IEEE 1394 device;

FIG. 7 shows IEEE1394 for easy understanding of the present invention.
Diagram showing a self-ID packet format conforming to the standard

FIG. 8 is a flowchart showing processing according to the related art.

FIG. 9 shows an IEEE1394 according to the embodiment of the present invention.
Equipment configuration diagram

FIG. 10 shows IEEE139 according to the embodiment of the present invention.
Configuration diagram of 4 devices

[Explanation of symbols]

101, 102, 103, 104, 105 IEEE1
394 equipment 201 IEEE 1394 equipment on the receiving side 202 IEEE 1394 equipment on the transmitting side 900 IEEE 1394 equipment 910 Node ID calculation means 920 Node ID comparison management means

Claims (8)

[Claims] 1. A data processing device for receiving at least digital data on a network constructed by an IEEE 1394 serial bus, wherein when a transmission stream transmitted by a node connected to a specific connection port is received, the IEEE 1394 serial bus is transmitted. A data processing device for recognizing whether or not a node connected to the specific connection port has received a transmission stream to be transmitted, even after reconfiguration of a network due to a bus reset of a bus. 2. A node ID calculating means for calculating a node ID of a node connected to the specific connection port using a self-identification packet; a node ID calculated by the node ID calculating means; Comprises node ID comparison and management means for comparing and managing the node IDs assigned to the transmission streams received by the server, and using information managed by the node ID comparison and management means,
2. The apparatus according to claim 1, further comprising recognizing whether a node connected to the specific connection port has received a transmission stream to be transmitted, even after reconfiguration of the network by bus reset of the IEEE 1394 serial bus. 3. Data processing device. 3. When a network is reconfigured by resetting the IEEE 1394 serial bus while receiving a transmission stream transmitted by a node connected to the specific connection port, the node ID calculating means Calculating a new node ID of a node connected to the specific connection port, the node ID comparison and management means determines whether or not the data processing apparatus is to rebuild the network with the new node ID calculated by the node ID calculation means. The data processing device compares the node IDs assigned to the transmission streams received later, and when the comparison results match, the data processing device
Even after reconfiguration of the network due to the bus reset of the IEEE 1394 serial bus, it is recognized that the transmission stream transmitted by the node connected to the specific connection port has been received, and when the comparison result does not match, the data processing device 3. The device according to claim 2, wherein after reconfiguring the network by resetting the IEEE 1394 serial bus, recognizes that a transmission stream transmitted by a node connected to the specific connection port has not been received. Data processing equipment. 4. The data processing apparatus according to claim 1, wherein
If the node connected to the specific connection port recognizes that the transmission stream transmitted by the node connected to the specific connection port has not been received after the reconfiguration of the network by the bus reset of the 94 serial bus, a notification unit for notifying the recognition to the outside is provided. 4. The data processing device according to claim 3, wherein: 5. The specific connection port has the largest port number among the ports of the data processing device, and the largest port of the ports of the node transmitting the transmission stream. 3. The data processing device according to claim 2, wherein the data processing device is used in connection with a device having a number. 6. The data processing apparatus according to claim 2, wherein the transfer mode conforming to the IEEE 1394 standard is an isochronous (synchronous) transfer mode. 7. A medium carrying a program and / or data for causing a computer to execute all or a part of the functions of all or part of the present invention according to claim 2, wherein the medium is processed by a computer. A medium characterized by what is possible. 8. An information aggregate, which is a program and / or data for causing a computer to execute all or a part of the functions of all or part of the present invention according to claim 2.