JP2000013399A - Network device identification method - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To realize centralized ID management avoiding a case where an ID is changed before and after resetting an ID. In an identification method for identifying a plurality of network devices of the same type connected on a network, a device identification tag for identifying the network devices of the same type within a predetermined category is assigned to the network device. Each of the network devices of the same type is identified based on the device identification tag while being assigned to each.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to data transfer between network devices, and more particularly to the identification of network devices of the same type when there are at least two or more network devices of the same type on a network.

[0002] More specifically, the present invention can be applied to the identification of devices on a network and a network having an address configuration conforming to IEEE1212, and particularly to the identification of network devices conforming to IEEE1394.

[0003]

2. Description of the Related Art Conventionally, as a network device identification method of this kind, there is, for example, IEEE 1394 which is a new high-speed serial interface standardized by IEEE (American Institute of Electrical and Electronics Engineers).

When a bus reset is detected, an identifier (ID) is automatically added to a network device conforming to IEEE 1394, but when a bus reset occurs again, a bus reset is performed on the network device again. Since the guarantee that the same ID as the previous ID is added is not defined, the ID may change before and after the bus reset again. Therefore, IEEE13
The same type (for example, printer, scanner, hard disk, personal computer (P
C), a video camera, etc.), when there is at least two or more network devices, if a new bus reset occurs, the ID may be changed, so that the network devices used before the bus reset cannot be used. And may be connected to another similar network.

[0005] With only the ID management as described above, there is a possibility that the ID may change after the bus reset, and it is difficult to manage the network devices using a unified ID. For this reason, in the IEEE 1394-1995 standard, the configuration ROM has a 64-bit configuration of node_vendor, chip_
It is stipulated that IDs such as id_hi and chip_id_lo must be unifiedly managed on the vendor side that supplies the network so as not to overlap (conflict).

[0006]

However, when a plurality of network devices of the same type are connected on a network, it is generally considered that the ID management method is different for each vendor supplying the network. May interconnect different networks,
If the network device connected to one network is disconnected and connected to the other network, or if a bus reset occurs at any time, the ID
Is reset, the ID is also changed before and after the ID is reset.
The problem that D may be changed, network equipment used before this ID reset may be unusable, and connection to another network of the same type is still solved. It has not been.

SUMMARY OF THE INVENTION An object of the present invention is to solve such a conventional problem. In particular, when connecting a plurality of network devices of the same type on a network, different vendors interconnect the different networks. In such a case, if the network device connected to one network is disconnected and connected to the other network, or if a bus reset occurs at any time, the ID may be changed before and after resetting the ID. Provide a method for identifying network devices that realizes centralized ID management that avoids cases and prevents cases in which network devices used before ID resetting become unusable and cases that are connected to another network of the same type. It is intended to be.

[0008]

According to a first aspect of the present invention, there is provided an identification method for identifying a plurality of network devices of the same type connected to a network. A device identification tag for identifying the same type of network device within the category of each of the network devices, and identifying each of the same type of network device based on the device identification tag. It is an identification method.

According to the first aspect of the present invention, each of the same type of network device is identified based on a device identification tag for identifying the same type of network device within a predetermined category. When connecting multiple network devices of the same type on the top, when vendors interconnect different networks, when disconnecting network devices connected to one network and connecting to the other network, Alternatively, even when a bus reset occurs at any time, it is possible to realize centralized ID management that avoids the case where the ID is changed before and after resetting the ID.
This makes it possible to avoid the case where the network device used before the resetting becomes unusable or the case where the device is connected to another network of the same type.

According to a second aspect of the present invention, in the method for identifying a network device according to the first aspect, when the predetermined trigger signal is generated in the network, the device identification tag is used in response to the trigger signal. This is a network device identification method in which devices communicate with each other on a network and are uniquely set within the category.

According to the invention described in claim 2, according to claim 1,
In addition to the effects described in (1), unified ID management can be realized based on a device identification tag uniquely set within a category.

According to a third aspect of the present invention, in the network device identification method according to the first aspect, the resetting of the device identification tag is not executed unless the trigger signal is newly generated. It is.

According to the third aspect of the present invention, the first aspect is provided.
In addition to the effects described in (1), unified ID management can be realized at a timing corresponding to the generation of a trigger signal.

According to a fourth aspect of the present invention, there is provided the network device identification method according to the first aspect, wherein the two networks are interconnected, and the network devices of the same type are connected in the two networks. This is a network device identification method in which when a conflict occurs in which the device identification tag is the same, the device identification tag is reset for the conflicting network device.

According to the invention described in claim 4, according to claim 1 of the present invention,
In addition to the effects described in (1), it is possible to realize centralized ID management that eliminates conflicts.

According to a fifth aspect of the present invention, in the network device identification method of the fourth aspect, a network device identification method for resetting the device identification tag for a network device additionally connected to a network. It is.

According to the invention described in claim 5, according to claim 4,
In addition to the effects described in (1), unified and limited ID management for network devices additionally connected to the network can be realized.

According to a sixth aspect of the present invention, in the method for identifying a network device according to the fifth aspect, the network device additionally connected to the network re-connects the device identification tag after resetting the power of the device. This is a network device identification method for a network device that has not been set.

According to the invention described in claim 6, according to claim 5,
In addition to the effects described in (1), centralized ID management can be realized at a timing corresponding to the occurrence of a power reset.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the following embodiments, as a network embodiment, a network conforming to a communication protocol of IEEE 1394-1995, which is a new high-speed serial interface standardized by IEEE (American Institute of Electrical and Electronics Engineers). An IEEE 1394 network is used. However, the present invention is not limited to this, and can be widely applied to any network capable of performing serial data communication and connecting network devices as nodes in a tree shape.

Each of the following embodiments is a method for identifying a plurality of network devices of the same type connected to an IEEE 1394 network, and is used to identify network devices of the same type within a predetermined category. This is characterized in that the device identification tag TAG is assigned to each of the network devices, and the same type of network device is individually identified based on the device identification tag TAG. Here, examples of the network device include an AV device, a printer, a digital camera, and a personal computer.

The network device identification method according to the first and second embodiments is based on the IEEE 1394-199.
Physical layer (PH) defined in the protocol stack
Y layer), link layer, BM (Bus Manag)
er), and implemented and executed in a transaction layer or the like. Here, the PHY layer and the link layer are composed of hardware in silicon.
The BM and the transaction layer are configured by software.

For this reason, each network device is a PHY
Packets are transmitted and received (for example, isochronous transfer and asynchronous transfer) to and from other network devices while being connected to the IEEE 1394 network via the layer.

(First Embodiment) A first embodiment will be described with reference to FIGS.
An embodiment will be described. Now, as shown in FIG. 1, a scanner (Scanner) having a different device identification tag TAG is used.
r (node ID ?, TAG # 1), one form of network equipment) and a printer (Printer (Node ID ?, TAG # 0), one form of network equipment) having the same device identification tag TAG as additional nodes IEEE
1394 network (IEEE13
94 network), and as a result, FIG.
As shown in the figure, Scanner (node ID # 1, TA
G # 1) and Printer (node ID # 0, TAG #)
0) was connected to the IEEE 1394 network,
The node ID of each device has changed. Specifically, Sc
anner (node ID # 1, TAG # 0) → Scan
ner (node ID # 3, TAG # 0), computer (Computer (node ID # 0, TAG # 0),
Network device) → Computer (Node ID # 2, TAG # 0), Printer (Node I
D # 2, TAG # 0) → Printer (node ID #)
4, TAG # 1) is considered.

In this embodiment, resetting of the device identification tag TAG is not executed unless a new bus reset occurs. The device identification tag TAG is
It is set so that it will not be changed unless it is set again, or saved even if the power of the network device is cut off. As a result, unified node ID management can be realized at a timing corresponding to the occurrence of a bus reset.

In this embodiment, two IEEE13
94, when a conflict occurs between two network devices of the same type in which the tag TAG for device identification is the same in two IEEE 1394 networks, the device identification for the conflicting network device is performed. The tag TAG is set to be reset. This makes it possible to implement centralized node ID management that releases conflicts.

In the present embodiment, the setting is made so that the device identification tag TAG is reset for the network device additionally connected to the IEEE 1394 network. As a result, unified and limited node ID management for network devices additionally connected to the IEEE 1394 network can be realized.

Here, a network device additionally connected to the IEEE 1394 network is a network device in which the device identification tag TAG has not been reset since the device power was reset. As a result, unified node ID management can be realized at a timing corresponding to the occurrence of a power reset.

More specifically, the device identification tag TA
The value of G is stored in a chip node ID in a configuration ROM defined by IEEE1212. In the present embodiment, in particular, ControlS, which is a control register defined in the CSR architecture of IEEE1212, is used.
It is stored in the configuration ROM of the status register (CSR).

Node_Unique_ID, Bus_Inf are stored in such a configuration ROM.
Node_Vendor_ID in o_Block (2
4 bits), chip_id_hi (8 bits), ch
Fields such as ip_id_lo (32 bits) are provided.

FIG. 3 is a flowchart for explaining the operation of the network device identification method according to the first embodiment.

When tab creation is started in step S100, the type of the network device (Printer, S
(canner, Computer).

In the search for the network device, Node_Unique_ID or Bus_In which is a data field in the configuration ROM in the CSR.
Node_Vendor_ID in fo_Block
(24 bits), chip_id_hi (8 bits),
Search for the same chip_id_lo (32 bits) (see FIG. 4).

The configuration ROM is held in a register space in a memory space of each network device. In the register space, a memory space for a CSR core register, a serial bus register, and a unit space register compliant with the CSR architecture is prepared.

Device identification tag TA used in the first embodiment
G is Node_Un as shown in FIG. 5, FIG. 6, and FIG.
It can be implemented in chip_id_hi (8 bits) or chip_id_lo (32 bits) in the equal_ID leaf.

Here, the value of the device identification tag TAG is stored even if the power of the network device is turned off, and is not changed unless it is set.
Specifically, it is stored on a backup power supply or stored on a nonvolatile RAM.

When the device identification tag TAG is mounted on the chip_id_hi in FIGS. 5 and 7, Node_Ve
A network device is searched using ndor_ID and chip_id_lo as search keys.

On the other hand, when the device identification tag TAG is mounted on chip_id_lo in FIG. 6, Node_Ve
A network device is searched using the contents of ndor_ID and chip_id_hi as search keys.

Next, in step S200, the device identification tag TAG of the same type of network device is automatically set. Step S200 is executed for all types of network devices.

Step S200 will be described in more detail with reference to the flowchart of FIG.

At the time when step S200 is entered, the IEEE
The type of the 1394 network (denoted as “type” in FIG. 8) is designated as x (X). First, the number N of network devices of type x is searched (step S210).

When the number N of network devices found in step S210 is 1 (YE in step S220)
S) (Computer device in the example of FIG. 2), the same type of network device does not exist. Therefore, the tag TAG (x,
0) is set to 0 (step S221).

In a case where two Scanners are connected as shown in FIG. 1, one Scanner is connected to the IE.
If you are already connected on the EE1394 network and want to add another Scanner,
Scanner (node ID to be added)
? , TAG # 1) has already been used on the IEEE 1394 network, and the value of the device identification tag TAG is set to 1. Since the device identification tags TAG of all Scanners are all different (YES in step S230), the device identification tags TAG of these two Scanners do not change. That is, Scanner (node ID1, TAG # 0) → Scanner (node I
D3, TAG # 0) and the Scanner (node I
D? , TAG # 1) → Scanner (node ID1,
TAG # 1).

On the other hand, the Printer (node ID ?, TAG # 0) shown in FIG. 1 is trying to connect to the IEEE1394 network for the first time. Therefore, two P
Since the value of the device identification tag TAG is the same (both are TAG # 0), the device identification tag TAG
The (x, i) reattachment process (step S240) is performed. Specifically, the value of the device identification tag TAG of Printer found first is set to 0. Next found P
The value of writer is the device identification tag TA found earlier.
It is set to a value that is one greater than the value of G.

Specifically, Printer (node ID)
2, TAG # 0) → Printer (node ID 4, T)
AG # 1), Printer (node ID ?, TAG #)
0) → Printer (node ID 0, TAG # 0). Thus, the value of the device identification tag TAG increases by the number of connected Printers.

FIG. 9 shows a device identification tag TA according to the present invention.
FIG. 9 shows a network configuration diagram of another embodiment of a G setting method. FIGS. 10 and 11 are flowcharts for explaining the operation of setting the device identification tag by bus reset.

The network identification flow of FIG. 3 can be used as an upper flow of the flow of FIGS. 10 and 11, similarly to the above-described example of the network identification flow shown in FIG.

The device identification tag TAG used in the identification flow of the IEEE 1394 network shown in FIG. 10 is not limited to being mounted on chip_id_hi shown in FIG. 7, but can be mounted on chip_id_lo.

The value of the device identification tag TAG of this embodiment is backed up by a backup power supply or a nonvolatile RAM even when the power supply of the network device is cut off. EntryFlag (1 bit) and Ch shown in FIG.
eckFlag (1 bit) is initialized (reset) to 0 (zero) when the power of the network device is turned on.
Is done.

Also, when a predetermined trigger signal is generated in the IEEE 1394 network, each of the network devices responds to the trigger signal by the device identification tag TAG.
It is set so that they can communicate with each other on the E1394 network and be set uniquely within a category.

Specifically, the device identification tag TAG of the same type of network device is set after a bus reset (trigger signal) occurs in the IEEE 1394 network. As specified in IEEE 1394, the bus reset is performed when the power of the network device is initially turned on, when another node is connected during operation, when a certain node is disconnected, or when another IEEE 1394 network is connected and integrated. When a simplified bus is formed, two I
Occurs when an EEE1394 network is divided, when a branch is disconnected, when a connected node is turned on or off, or when it is detected that some change has occurred in the tree structure of the network. Characteristics. In addition, IEEE1394-19
The 95 standard also specifies that a configuration function is generated in response to a bus reset.

This makes it possible to implement centralized node ID management based on the device identification tag TAG uniquely set in the category.

FIG. 9 shows an example of the network configuration shown in FIG.
The operation of setting the device identification tag TAG by such a bus reset will be described with reference to the flowchart of FIG.

FIG. 9 shows that three network devices having an IEEE 1394 interface function (for example, one computer and two printers in the figure) are turned on, the network devices are connected to an IEEE 1394 network, and a bus reset is performed. Indicates a state in which is ended.

The node ID is a node ID of the IEEE 1394 network. TAG, EntryFlag,
The value of CheckFlag indicates the value of FIG. 7 described above. Since the power of the network device has been turned on and the bus reset has been completed, the EntryFlag and the CheckFlag are checked.
The value of Flag is 0 (zero).

First, it is assumed that Computer is selected as the type of the IEEE 1394 network. At this time, the values of EntryFlag and CheckFlag are 0
Since it is (zero), the process proceeds to the process of step S330.

If the type of the network device is Compute
In the case of r, the node whose value of the device identification tag TAG is 0 does not exist on the IEEE 1394 network (NO in step S340), so that the process proceeds to step S350, and the value of EntryFlag is set to 1.

Step S following step S350
In the process of 360, the device identification tag TAG # 0 is registered in the tag map in which the device identification tag TAG is described.

Step S370 following step S360
In the processing of (1), the value of CheckFlag is set to 1 and the node is in a state of “tested”.

Further, step S following step S370
In the process of 310, since there is no node whose EntryFlag value is 0 (NO in step S310), the process is performed as shown in FIG.
The process proceeds to step S390 shown in FIG.

At this time, the tag queue is empty (step S39).
0 (YES), so IEEE called Computer
The setting processing of the device identification tag TAG of the type of the 1394 network ends.

Subsequently, a tag map in which the device identification tag TAG is described will be described.

The tag map in which the device identification tag TAG is described is described in a 64-bit tag map register in which the device identification tag TAG is described as shown in FIG. Here, LSB of TagMapReg_lo
(Least Significant Bit), tag TAG # 0 for device identification with MSB (Most Significant Bit).
nifant Bit) for device identification tag TAG #
It can be determined whether or not 31 has been registered. TagMa
Device identification tag TAG # 32 with LSB of pReg_hi
Can be determined by using MSB-1 (the bit next to the MSB) as to whether or not the device identification tag TAG # 62 has been registered. After the bus reset, the value of the map register in which the device identification tag TAG is described is set to 0, and all the device identification tags TAG are unused. This map register is prepared for each type of network device.

Next, an operation of setting a device identification tag TAG of a network device named Printer will be described with reference to FIGS.

In step S310, EntryF
A node whose lag value is 0 is searched. IEEE of FIG. 9
In the E1394 network, there are two Printers, but the one with the smaller node ID (that is, the node ID is 1
The search is started from the node of ().

Since the value of the device identification tag TAG of the node having the node ID # 1 is 0 and the same value as the device identification tag TAG of the node having the node ID # 2 is 0 (N in step S330).
O), the process proceeds to step S340.

Step S350 following step S340
In the process of (3), since the value of the Entry Flag of the node ID # 2 is not 1 (NO in step S340), Pri
Then, the device identification tag TAG # 0 of the tag map in which the device identification tag TAG is described is registered and set (EntryFlag: = 1 in step S350 → step S360).

Step S370 following step S360
In the process (1), the value of CheckFlag is set to 1, and the process returns to step S310.

Step S310 following step S370
In the processing of EntryFl of the node with the node ID # 2
Since the values of ag and CheckFlag remain 0, the process proceeds to the process of step S330 (YES in step S310 → step S320 → step S330).

Here, a node having the same value of the device identification tag TAG as the device identification tag TAG of the node ID # 2 is a node having the node ID # 1.

In the process of step S340, the node ID
Since the value of the EntryFlag of the node # 1 is 1 (YES in step S340), the process proceeds to step S370.

In the processing of step S370 following YES of step S340, CheckFl of node ID # 2
The value of ag is set to 1, and the process returns to step S310.

Step S310 following step S370
In the processing of the above, the node of the node ID # 2 is still Entry
Since the value of Flag is 0 (YE in step S310)
S), the process proceeds to step S320.

Step S320 following step S310
In the processing of (1), the value of CheckFlag is 1 (step S
Since it is 320 (YES), the process jumps to step S380 to put the node with the node ID # 2 into the tag queue.

Step S381 following step S380
Since there is no node whose CheckFlag value is 0 (NO in step S381), the process proceeds to step S390.

In step S391 shown in FIG. 11, the node having the node ID # 2 is obtained from the tag queue. Where Pr
A map in which the device identification tag TAG of inter is described is searched to obtain unused device identification tags TAG # 1 in ascending order (step S391 → step S392).
→ NO in step S393).

Step S following NO in step S393
In the process of 394, the unused device identification tag TAG # 1
Is set to the device identification tag TAG of the node ID # 2,
Set the values of EntryFlag and CheckFlag to 1 (EntryFlag: = 1, CheckFlag:
= 1), and the process returns to step S390.

Step S390 following step S394
Since the tag queue is empty (YES in step S390), the process ends.

On the other hand, when it is determined in step S393 that there is no unused tag (YE in step S393).
S), the process ends after the process of displaying the error “No unused tag” is executed.

(Second Embodiment) Next, a second embodiment will be described with reference to FIG. The IEEE 1394 network identification flow uses the flow of FIG. 10 described above.
Note that the same parts as those already described in the first embodiment are denoted by the same reference numerals, and redundant description will be omitted.

FIG. 13 shows the IEEE 1394 of FIG. 9 described above.
This shows a state in which two more printers are additionally connected to the network and the bus reset has been completed.

In the figure, in the process of step S310, since the value of the EntryFlag is 0 at the node of node ID # 0, it is determined that there is a node with the value of the EntryFlag of 0 (YES in step S310).
The node of D # 0 is searched.

In the processing of step S320 following YES of step S310, the Che of the node of node ID # 0
Since the value of ckFlag is 0, CheckFl of the node
Judge that the value of ag is not 1 (NO in step S320)
Then, the process proceeds to step S330.

Step S following NO in step S320
In the process of 330, since there is a node having the node ID # 3 having the same device identification tag TAG # 0 as the node ID # 0, the node ID # 3 having the same device identification tag TAG # 0 as the node ID # 0 is present. Judge that there is a node (step S
(NO at 330), and then the process proceeds to step S340.

Step S following NO in step S330
In the process of 340, the Entr of the node with the node ID # 3
Since the value of yFlag is 1, it is determined that the value of EntryFlag of the node having the node ID # 3 is 1 (step S34).
(YES at 0), the process proceeds to step S370.

In step S370, the value of CheckFlag of the node with node ID # 0 is set to 1 (Ch
eckFlag: = 1), and returns to step S310.

Step S310 following step S370
In the processing of the above, the node with the node ID # 0 is still Entr
Since the value of yFlag is 0, the process proceeds to step S320.

In the process of step S320, the node ID
Since the value of CheckFlag of the node # 0 is 1, it is determined that the value of CheckFlag of the node of node ID # 0 is 1 (YES in step S320), the process proceeds to step S380, and the node ID # 0 is stored in the queue. Put in.

Step S381 following step S380
Since there is a node having a CheckFlag value of 0 (node with node ID # 1) (YES in step S381), the process returns to step S310 again (step S3).
81 → Step S310).

In the process of step S310, EntryFlag, Che
Since both ckFlags are 0 (YES in step S310)
→ NO in step S320), and the process proceeds to step S330.

Step S following NO in step S320
In the process of 330, since no node having the same device identification tag TAG as the node ID # 1 exists (step S3).
(NO in S30), the process proceeds to step S350.

Step S following NO in step S330
In the process of 350, the Entr of the node with the node ID # 1
Set the value of yFlag to 1.

Further, in the process of step S360 following step S350, the device identification tag TAG of node ID # 1 (the value at this time = 2) is registered in the map describing the device identification tag TAG of Printer. .

Step S370 following step S360
Then, the value of CheckFlag is set to 1, and the process returns to step S310.

Step S310 following step S370
In the processing of (3), there is no node whose EntryFlag value is 0 (NO in step S310), so that step S390 is performed.
Proceed to processing.

Step S following NO in step S310
In the process of 390, since the tag queue is not empty (NO in step S390), the process of step S391 is executed to obtain the device identification tag TAG of node ID # 0 from the tag queue.

Step S392 following step S391
Then, a map in which the device identification tag TAG of Printer is described is searched (step S392) to obtain an unused device identification tag TAG (value = 4).

Step S393 following step S392
In the processing of (3), since there is an unused device identification tag TAG (NO in step S393), the process proceeds to the processing in step S394.

Step S following NO in step S393
In the process of 394, the Entr of the node with the node ID # 0
The values of yFlag and CheckFlag are set to 1, and the process returns to step S390.

Step S390 following step S394
Then, since the tag queue is empty (step S390)
YES), the process ends.

As described above, according to the first or second embodiment, the device identification tag TA for identifying the same type of network device within a predetermined category.
Since each of the network devices of the same type is identified based on G, when connecting a plurality of network devices of the same type on the IEEE 1394 network, if the vendors interconnect different IEEE 1394 networks, one of the IEEE 1394 networks is connected to the other. To remove the network device connected to the other IEEE 139
Even if the connection to the network 4 or the bus reset occurs at any time, the node I
D It is possible to realize centralized node ID management that avoids the case where the node ID is changed before and after resetting, and as a result, the network device used before the node ID resetting becomes unusable. It becomes possible to avoid the case of being connected to another same type of IEEE 1394 network.

[0102]

According to the present invention, when connecting a plurality of network devices of the same type on a network, if the vendors interconnect different networks, the network device connected to one network is removed and the network device is connected to the other network. Even if connection is made or a bus reset occurs at any time, the I / O
By realizing centralized ID management that avoids the case where D is changed, it is possible to avoid the case where the network device used before the ID reset becomes unusable and the case where it is connected to another same type of network. Become like

[Brief description of the drawings]

FIG. 1 is an IEEE 1394 network configuration diagram for describing a first embodiment of a network device identification method according to the present invention.

FIG. 2 shows a state in which a scanner and a printer are additionally connected to the IEEE 1394 network of FIG. 1;

FIG. 3 is a flowchart illustrating an operation of the network device identification method according to the first embodiment.

FIG. 4 is a diagram showing a data structure of a Node_Unique_ID leaf which is a data field in a configuration ROM in CSR.

5 is a diagram for explaining a data structure in which a device identification tag is mounted on chip_id_hi in a Node_Unique_ID leaf of FIG. 4;

FIG. 6 is a diagram for explaining a data structure in which a device identification tag is mounted on chip_id_lo in a Node_Unique_ID leaf of FIG. 4;

FIG. 7 is a diagram for explaining another data structure in which a device identification tag is mounted on chip_id_hi in the Node_Unique_ID leaf of FIG. 4;

FIG. 8 is a flowchart illustrating a process of automatically setting a device identification tag of the same type of network device.

FIG. 9 is a network configuration diagram of another embodiment of a process for automatically setting a device identification tag of the same type of network device.

FIG. 10 is a flowchart illustrating an operation of setting a device identification tag by a bus reset.

FIG. 11 is a flowchart illustrating an operation of setting a device identification tag by a bus reset.

FIG. 12 is a diagram for explaining a data structure of a tag map register having a length of 64 bits.

FIG. 13 shows a state in which two more printers are additionally connected to the IEEE 1394 network of FIG. 9 and a bus reset has been completed.

[Explanation of symbols]

TAG: Device identification tag TAG #: Tag number Printer: Printer Scanner: Scanner Computer: Computer CSR: Control Status Register
er

Claims (6)

[Claims] 1. An identification method for identifying a plurality of network devices of the same type connected to a network, the device comprising a device identification tag for identifying the network devices of the same type within a predetermined category. A network device identification method characterized by assigning to each device and identifying each of the same type of network device based on the device identification tag. 2. The device identification tag is configured such that when a predetermined trigger signal is generated in a network, each of the network devices communicates with each other on a network in response to the trigger signal and is uniquely set in the category. 2. The network device identification method according to claim 1, wherein: 3. The network device identification method according to claim 1, wherein resetting of the device identification tag is not executed unless the trigger signal is newly generated. 4. In a case where two networks are interconnected, when a conflict occurs in the two networks in which the same device identification tag is the same between network devices of the same type, the conflict occurs. 2. The network device identification method according to claim 1, wherein resetting of the device identification tag is performed for a network device. 5. The network device identification method according to claim 4, wherein the device identification tag is reset for a network device additionally connected to the network. 6. The network device according to claim 5, wherein the network device additionally connected to the network is a network device in which the device identification tag has not been reset after the power of the device is reset. Device identification method.