JP2003152728A - Data communication method, transmission reception circuit, information device provided with the transmission reception circuit, and information communication network - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transmission reception circuit that can transmit/receive added information between nodes in the case of automatically reconfiguring a network by an added or eliminated node. SOLUTION: The transmission reception circuit 10 is provided to a node to transmit/receive a data signal and an arbitration signal (control code) between nodes. The transmission reception circuit 10 is provided with a transmission section and a reception section. The transmission section is provided with: a PHY state machine 11 for generating a control code; a BUS- RESET generation request generating circuit 13 that generates a BUS- RESET generation request signal (information code); and a multiplexer 15 that selects and transmits either code of the control code and the information code under the control of the PHY state machine 11. The reception section is provided with a Dilution discrimination circuit 18 that discriminates whether the received signal is the control code or the information code.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a personal computer, peripheral equipment thereof, a data communication method used for a serial bus for connecting audiovisual equipment, a transmitting / receiving circuit, an information equipment including the transmitting / receiving circuit,
And an information communication network using the information equipment.

[0002]

2. Description of the Related Art As the communication standard of the serial bus,
Institute of Electrical and Electronics Engineers (IEEE) 1394 High Performance Serial Bus Standard (hereinafter referred to as “IEEE139
4 standards ”. ).

According to the IEEE 1394 standard, 100 (9
8.304) Mbps, 200 (196.608) Mb
Data transfer at ps, 400 (393.216) Mbps is specified, and a 1394 port having a higher transfer rate is specified to maintain compatibility with the lower transfer rate. The numbers in parentheses show the actual transfer rates. As a result, 100 Mbps, 200 Mbps,
Data transfer rates of 400 Mbps can be mixed on the same network.

According to the IEEE 1394 standard, FIG.
As shown in, the transfer data is converted into two signals of DATA (data) and STROBE (strobe) that complements the signal, and CLOCK (clock) is generated by taking the exclusive OR of these two signals. DS-Link (Data / StrobeLi)
nk) The encoding format transfer format is adopted.

Arbitration signals in the physical layer (physical layer) are TPA / TPA *, TPB / T.
It is represented by two twisted pair lines of PB *. The pair of twisted pair lines TPA / TPA * transmits a strobe signal (Strb_TX) and receives a data signal (Data_RX). On the other hand, the other twisted pair line TPB / TPB * is connected to the data signal (Data
_TX) and the strobe signal (Strb
RX) is received.

Strb_Tx signal, Data_Tx signal, Strb_Enable signal and Data_Ena
The ble signal is used to generate an arbitration signal (Arb_A_Rx, Arb_B_Rx) from the control code. Here, the value of the transmission arbitration signal and its meaning are as shown in FIG.
The received arbitration signal and its meaning are as shown in FIG.

Further, in the IEEE 1394 standard, two types of methods, daisy chain and node branch, can be used as the connection method. 139 in the daisy chain system
Devices with 4 ports can connect up to 16 nodes,
The maximum distance between the nodes is 4.5m. Also, by using node branching together, the maximum of 43
A network that can connect to nodes (physical node addresses) can be configured.

According to the IEEE 1394 standard, it is possible to connect / disconnect the cable while the device is operating, that is, while the power is on, and automatically when a node is added or deleted. It is designed to reconfigure the network. At this time, the device of the connected node can be automatically recognized, and the ID and arrangement of the connected device are managed on the transmission / reception circuit.

According to the IEEE 1394 standard, the states of a network constituted by a bus conforming to the standard are roughly classified into a BUS_RESET phase, T
There are four states: REE_ID phase, SELF_ID phase, and DATA_TRANSFER phase.

In the BUS_RESET phase, the BUS_RESET arbitration code transmitted by a certain node is transmitted to the entire bus, and the network is initialized. In the TREE_ID phase, parent-child determination is performed between the nodes based on the initialized network topology, and the node that finally became the parent node becomes the root node and manages subsequent buses.

In the SELF_ID phase, information about the self node (node ID, transferable speed, etc.) is passed to SELF_I.
Allocate to a predetermined area in the D packet and select SEL on the bus.
Send the F_ID packet. Other nodes can obtain the information of each node connected to the bus by analyzing each area of the SELF_ID packet received via the bus. In the DATA_TRANSFER phase, normal data transfer is possible.

Since the above-mentioned four states transit in order, in order to perform normal data transfer, the SELF_ID phase must be normally completed.

The operation of each node until the root node is determined in the TREE_ID phase will be described below with reference to FIG. FIG. 18 shows a state in which seven nodes A to G are connected in a tree shape.

There are the following rules for parent / child determination in the TREE_ID phase. 1. A node having one port connected (hereinafter, referred to as "leaf node") immediately transmits PARENT_NOTIFY to the port. 2. PARE from the connected port
The node receiving NT_NOTIFY transmits CHILD_NOTIFY to the port. This allows PARENT_NOTIFY and CHILD_N
PARENT_NO between the nodes that sent and received OTIFY
The node that received TIFY becomes the parent node and CHIL
The node that receives D_NOTIFY becomes the child node.
3. A node having two or more connected ports (hereinafter referred to as a “branch node”) has only one remaining connected port whose parent-child determination with the partner node has not yet been completed. Then, PARENT_NOTIFY is transmitted to the port. 4. 1 to above
Finally, with the rule of 3 applied, CHILD
The node that transmits _NOTIFY and becomes the parent node becomes the root node.

The above rule is applied to the case of FIG.
First, the leaf node Node D sends data to the branch node Node B from the ports p0 to PARENT_N.
OTIFY is sent, and the node B sends PAR from port p0.
Upon receiving ENT_NOTIFY, port p0 to C
Send HILD_NOTIFY.

By this handshake, the node B becomes the parent node and the node D becomes the child node. Similarly, parent-child determination is performed between the node B and the node E, between the node C and the node F, and between the node C and the node G, and the nodes B, C and C becomes a parent node, and nodes E, F, and G become child nodes.

Next, the node B transmits PARENT_NOTIFY from the remaining port p2 to the node A because the two ports p0 and p1 out of the three connected ports p0 to p2 have completed the parent-child determination. To do. When the node A receives PARENT_NOTIFY from the port p0, the node A sends CHILD_NO to the node B.
Send TIFY.

By this handshake, the node A becomes the parent node and the node B becomes the child node. Similarly, parent-child determination is performed between the node A and the node C,
The node A becomes a parent node and the node C becomes a child node.

Finally, the node A, which has become the parent node by transmitting CHILD_NOTIFY, becomes the root node,
Then manage the bus.

When parent-child determination is performed as described above, when a loop is formed on the network topology, all nodes constituting the loop become branch nodes, and two or more connected ports complete parent-child determination. However, the TREE_ID phase does not end. Therefore, IEEE 1394-1995 and IEEE 139
The 4a-2000 standard prohibits the formation of loops.

Recently, POF (plastic optical fiber) is used as a communication path instead of a conventional metal cable, and IEEE1394-1995 and IEEE139 are used.
4a-2000 New communication method that enables packet transfer (OP i.LINK (registered trademark) Ver. 1.0)
Is proposed.

This system is a system for performing full-duplex communication with a single-core POF. If full-duplex communication is performed with a single-core POF and the clock speed of the other port is close to that of the own port, if the own port continues to send a periodic waveform,
It is known that the jitter is biased and the jitter tolerance indicating the allowable amount of the jitter is deteriorated.

In order to prevent this, in the above OP i.LINK (registered trademark) Ver. 1.0, as shown in FIG. 19, when the control signal is transmitted, the same control code is repeatedly transmitted instead of the conventional method. , The control code and the random data code are transmitted according to a predetermined rule.

As the random data, OP i.LINK
As shown in FIG. 20, (registered trademark) Ver. 1.0 specifies that a pseudo-random number generated by a pseudo-random number generation algorithm is used, which is called a primary that is exclusively determined between ports facing each other in a communication path. By using the bit signal, the correlation between the signals transmitted by the opposite nodes is reduced.

On the receiving side, the control code can be transmitted and received by updating the control code received by the own port only when the control code is received.

[0026]

In a network constructed based on the above serial bus standard, the following problems occur when the network is automatically reconfigured by adding or deleting nodes.

If a node is added or deleted during the transfer of data between nodes, the data transfer is interrupted, the data transfer is restarted after the network is reconfigured. For this reason, a delay occurs in data transfer, which is a problem when performing data transfer requiring real-time performance between nodes.

Further, a loop may be formed in terms of topology due to the addition of a node. As described above, in a network in which the formation of a loop is prohibited, it is necessary to detect the loop and identify the position. .

As an invention for detecting a loop, Japanese Patent Application Laid-Open No.
There is a bus system described in No. 00-4249. In this bus system, a loop detection device is provided in each node, the loop detection devices are connected in the same manner as the connection between the nodes, and the loop detection device performs loop detection to detect the loop and identify the position. I am doing it. When this bus system is used, loops can be detected with certainty, but as many loop detection devices as nodes are required.

Another invention for detecting a loop is a data transmission system described in Japanese Patent Laid-Open No. 2000-31973. In this data transmission system, each node has PARENT_NOTI in the TREE_ID phase.
The time during which FY is not transmitted / received is measured, and when the time has passed a predetermined time, it is determined that a loop is formed.

However, when a large number of nodes are connected, it takes a long time to decide a parent and child.
In this data transmission system, if the predetermined time is short,
It is possible to mistakenly determine that a loop is formed. Moreover, if the predetermined time is long, the time until the network is reconfigured becomes long.

An object of the present invention is to provide a data communication method or a transmission / reception circuit that can transmit / receive additional information between nodes when automatically reconfiguring a network by adding or deleting nodes.

[0033]

In order to solve the above problems, a data communication method of the present invention is a data communication method for transmitting and receiving a data signal and a control signal between nodes, and when transmitting the control signal. In addition to transmitting the control code at a predetermined interval, the information code is transmitted at a predetermined timing other than the timing of transmitting the control code.

Here, the information code includes information necessary for constructing an information communication network.

According to the above method, when transmitting the control signal, the information code can be transmitted and received together with the control code, so that the node can transmit and receive various information and automatically reconfigure the network. It is possible to solve various problems that occur when performing the operation by using various information transmitted and received.

For example, the information code may be a code requesting reconfiguration of the network. in this case,
When a node is added or deleted, the node transmits / receives a control code requesting reconfiguration of the network, and processing is performed based on the control code, whereby the network is automatically reconfigured.

At this time, according to the above method, the node
By transmitting the information code requesting the network reconfiguration before transmitting the control code requesting the network reconfiguration, it is possible to determine whether or not each node may immediately perform the network reconfiguration. Then, the node, which cannot be immediately executed, can wait for the network reconfiguration, for example, by transmitting a code waiting for the network reconfiguration as an information code.

As described above, by transmitting the code for requesting the reconfiguration of the network as the information code, it is possible to judge whether or not each node can immediately perform the reconfiguration of the network. The network can be reconfigured after processing that should be performed immediately, such as data transfer, is completed.

Further, the information code may be an identification code for identifying a node. In this case, when reconfiguring the network, the node
An identification code that identifies the node can be sent and received. By this, the node receives its own identification code transmitted from one port from another port,
It can be detected that a loop is formed.

The transmission / reception circuit of the present invention is a transmission / reception circuit provided in a node for transmitting / receiving a data signal and a control signal between nodes, and generates a control code and an information code as the control signal. A transmission unit having a code generation unit and a control unit for transmitting one of the control code and the information code generated by the code generation unit, and the received signal is the control code or the It is characterized in that it is provided with a receiving section having a discriminating section for discriminating whether or not it is an information code.

According to the above configuration, in the transmitting / receiving circuit, the transmitting unit can transmit the information code generated by the code generating unit, and the receiving unit determines the information code from the signal received from the other transmitting / receiving circuit. The information code can be received by discriminating at.

Therefore, the transmission / reception circuit of the present invention can transmit / receive various information by transmitting / receiving information codes. For example, various problems that occur when the network is automatically reconfigured are transmitted / received. It can be solved by various information.

For example, the information code may be a code for requesting network reconfiguration. in this case,
Whether each transceiver circuit may immediately reconfigure the network by transmitting the information code requesting the network reconfiguration before the transceiver circuit sends the control code requesting the network reconfiguration. You can judge. Then, the transmission / reception circuit, which cannot be immediately executed, can wait for the network reconfiguration by, for example, transmitting a code waiting for the network reconfiguration as an information code.

As described above, by transmitting the code for requesting the reconfiguration of the network as the information code, it is possible to judge whether or not each transmission / reception circuit can immediately reconfigure the network. The network can be reconfigured after processing that should be done immediately, such as required data transfers, is completed.

Further, the information code may be an identification code for identifying the transmitting / receiving circuit. In this case, when the network is reconfigured, the transmission / reception circuit can transmit / receive the control code and the identification code for identifying the transmission / reception circuit. Thus, the transmission / reception circuit can detect that its own transmission / reception circuit is one of the nodes forming the loop by receiving its own identification code transmitted from a certain port from another port.

Further, the transmission / reception circuit of the present invention has a plurality of ports connected to another transmission / reception circuit, an identification code received from a port of the plurality of ports, and its own identification code in the above configuration. Further comprising a comparing unit for comparing, the control unit, when the received identification code is greater than or smaller than the identification code of its own, in one case, its own identification code, in the other case Is characterized in that the received identification code is transmitted from a port different from the received port, and if the values are equal, it is determined that a loop is formed with another transmission / reception circuit.

According to the above configuration, among the transmission / reception circuits forming a loop, the transmission / reception circuit having the maximum or minimum identification code transmits its own identification code from a certain port, and then transmits / receives its own identification code from another port. Is received, which makes it possible to detect that it is one of the transmission / reception circuits forming a loop.

Further, in the transmitter / receiver circuit of the present invention, in the above structure, when the control section transmits the received identification code, the control section controls so as not to transmit the own identification code from the received port. The control code that determines the master-slave relationship with the transmission / reception circuit is controlled so as not to transmit its own identification code or the received identification code, or there is one port other than the port for which the master-slave relationship is determined. If it is, it is characterized by controlling so as not to transmit the own identification code or the received identification code from any of the ports.

When the transmission / reception circuit transmits the received identification code, the transmission / reception circuit of the other party should transmit the identification code of the transmission / reception circuit of the other party, even if the transmission / reception circuit of the transmission / reception circuit transmits the identification code of itself. And the transmission is wasted.

Further, the transmission / reception circuits forming the loop cannot determine the master-slave relationship with each other. From this, when the control code that determines the master-slave relationship with another transmission / reception circuit is received, it means that the transmission / reception circuit of the other party does not form a loop. Therefore, even if the identification code is transmitted from the port that has received the control code, the loop is not detected, and the transmission is wasted.

The fact that there is one remaining port other than the port for which the master-slave relationship has been determined means that this transmission / reception circuit does not form a loop. Therefore, even if the identification code is transmitted from this transmitting / receiving circuit, the loop is not detected, and the transmission becomes useless.

Therefore, the transmission / reception circuit of the present invention is controlled by the control unit so as not to transmit the identification code when any of the above conditions is satisfied, so that waste of transmission can be omitted. Also, because the information code is not sent,
Since a random data code can be transmitted, it is possible to suppress the reduction of the effect of dilution by transmitting the information code.

Further, in the transmitter / receiver circuit of the present invention, in the above structure, when the control unit determines that a loop is formed with another transmitter / receiver circuit, it transmits its own identification code. For port or received port,
The feature is that the loop is released by not transmitting a signal.

For example, in the case of OP i.LINK (registered trademark) standard, if the transmission / reception circuit does not receive a signal from a certain port for a predetermined period, the connection of the port is disconnected.

Therefore, by applying the transmission / reception circuit of the present invention to the specification such that the connection of the port is disconnected when the signal is not received from the certain port for a predetermined period as in the above standard, the loop is automatically generated. Can be eliminated.

Further, in the transmission / reception circuit of the present invention, in the above configuration, the control section identifies the information code only when initializing the network or determining the master-slave relationship with another transmission / reception circuit. It is characterized by sending a code.

A loop is formed when the network is initialized by adding or deleting nodes, and when the loop is formed, the master-slave relationship of each node cannot be determined.

Therefore, the transmission / reception circuit of the present invention transmits the identification code only when the loop is formed or when the formation of the loop causes a problem.
Waste of transmission can be omitted. In addition, since the information code is not transmitted, a random data code can be transmitted. Therefore, by transmitting the information code, the Dilutio
The reduction of the effect of n can be suppressed.

Further, in the transmitter / receiver circuit of the present invention, in the above-mentioned configuration, the code generation section further generates a flag signal for determining whether or not an information code exists, and the determination section determines that the received signal is It is characterized in that it is further determined whether or not it is the flag signal.

A conventional transmission / reception circuit that does not transmit / receive information codes will transmit a random data code during the information code transmission period. Therefore, if the information code and the random data code happen to match,
The above-mentioned transmission / reception circuit for transmitting / receiving the information code may misidentify the random data code as the information code.

Therefore, the transmission / reception circuit of the present invention can prevent the random data code from being mistaken for the information code by using the flag signal for determining whether or not the information code exists.

The information equipment of the present invention is characterized by including the above-mentioned transmitting / receiving circuit.

As a result, various problems that occur when the network is automatically reconfigured can be solved by the information devices transmitting and receiving various information.

The information communication network of the present invention is
It is characterized in that a plurality of the information devices are connected.

As a result, various problems that occur when the network is automatically reconfigured can be solved by transmitting and receiving various information within the network.

[0066]

DESCRIPTION OF THE PREFERRED EMBODIMENTS [Embodiment 1] An embodiment of the present invention will be described with reference to FIGS. In addition,
In this embodiment, IEEE 1394-1995 or I
A transmission / reception circuit used in the EEE1394a-2000 standard will be described. The same applies to other embodiments described later.

FIG. 1 is a block diagram showing a schematic configuration of a transmission / reception circuit according to this embodiment. The transmitter / receiver circuit 10
Includes a transmitter and a receiver, and the transmitter is a PH
Y state machine 11, Dilution generation circuit 1
2, BUS_RESET generation request generation circuit 13, BUS
_RESET standby request generation circuit 14, multiplexer 1
5 and transmitters 16 and 19, and the receiving unit includes receivers 17 and 20 and a dilution determination circuit 18.

The PHY state machine 11 uses the IEEE1
The state machine conforms to the 394 standard and generates an arbitration signal (control code) as shown in FIGS. 16 and 17. In addition, the PHY state machine 11
Performs various processes such as control of the multiplexer 15.

The Dilution generating circuit 12 is shown in FIG.
A random data code is generated using a pseudo random number generated by a pseudo random number generation algorithm as shown in.

BUS_RESET generation request generation circuit 13
Generates a BUS_RESET generation request signal (information code), and the BUS_RESET standby request generation circuit 14
A BUS_RESET standby request signal (information code) is generated.

When transmitting a control signal, the multiplexer 15 sends an arbitration signal from the PHY state machine 11, a random data code from the dilution generating circuit 12, and a BUS_RESET generating request signal from the BUS_RESET generating request generating circuit 13.
From US_RESET standby request generation circuit 14 to BUS_R
Each of the ESET standby request signals is received, and one of the signals is selected and transmitted to the transmitter 16 under the control of the PHY state machine 11.

The transmitter 16 converts the received signal into a predetermined format and transmits it to another transmitting / receiving circuit 10. Transmitter 1
6 is an LED (light emitting diode) or L in optical communication, for example.
Although D (laser diode) is used, it is not limited to this.

The receiver 17 converts the signal received from the other transmission / reception circuit 10 into a predetermined format,
It transmits to the discrimination circuit 18. For the receiver 17, for example, a photodiode is used in optical communication, but it is not limited to this.

The Dilution discrimination circuit 18 receives the received data as a random data code, an arbitration signal, a BUS_RESET generation request signal, and a BU.
Determine which of the S_RESET standby request signals,
A signal other than the random data code is transmitted to the PHY state machine 11.

The transmitter 19 is the PHY state machine 11
The signal received from is converted into a predetermined format and transmitted to another transmission / reception circuit 10. The receiver 20 is the other transmission / reception circuit 1
The signal received from 0 is converted into a predetermined format and transmitted to the PHY state machine 11.

It is assumed that two nodes N1 and N2 having the transmission / reception circuit 10 having the above-mentioned configuration are connected as shown in FIG. 2 (a). It is assumed that the node N1 is the root node. In this state, the transmission / reception circuit 10 in the nodes N1 and N2, when transmitting the control signal, as shown in format F10 of FIG. 3, in the case of the timing of transmitting the arbitration signal, the multiplexer 15
Selects the arbitration signal from the PHY state machine 11, there is no data to be transmitted, and it is not the timing to transmit the arbitration signal, the multiplexer 15 determines that the dilution generation circuit 1
Select a random data code from 2 and send it to transmitter 1
6 to the other node.

Next, consider the case where the node N3 is connected to the node N2 and the topology is changed as shown in FIG. At this time, when the PHY state machine 11 of the node N2 detects that the node N3 is connected by receiving a signal via the receiver 20, the node N2 of its own is not the root node, and therefore the PHY state machine of FIG. ), Which sends a random data code as shown in).
The multiplexer 15 is controlled so that a part of the ion period becomes the format F11 assigned to the period for transmitting the BUS_RESET generation request signal. As a result, the control signal having the format F11 is transmitted to the root node N1.

On the other hand, when the root node N1 receives the control signal having the format F11, it outputs Dilut.
The ion discriminating circuit 18 notifies the PHY state machine 11 that the BUS_RESET generation request signal is detected.

Here, for example, the root node N1 is a television receiver, the node N2 is a video recorder,
When the node N2 is recording the video output from the root node N1, the PHY state machine 11 of the root node N1 takes part of the dilution period for transmitting a random data code, as shown in FIG. BUS
A multiplexer 15 is provided so that the format F12 is assigned during the period for transmitting the _RESET standby request signal.
To control. As a result, the control signal having the format F12 is transmitted from the root node N1 to the node N2.

On the other hand, the node N2 has the format F
When receiving a control signal with 12, the Dilution
The determination circuit 18 notifies the PHY state machine 11 that the BUS_RESET standby request signal has been detected. At this time, the PHY state machine 11 of the node N2 is
Route node N1 to B without sending US_RESET
Wait to receive US_RESET.

When the recording is completed, the root node N1
Is BUS_RESET which is an arbitration signal
To the node N2 and reconfigured into a network having the topology shown in FIG.

Therefore, by using the transmission / reception circuit 10 of the present embodiment to allocate and transmit the BUS_RESET generation request signal or the BUS_RESET standby request signal during the dilution period, the system can unexpectedly transmit the B signal.
It is possible to suppress the occurrence of US_RESET and achieve stable operation of the application.

[Second Embodiment] Next, another embodiment of the present invention will be described with reference to FIGS. The present embodiment is a transmission / reception circuit having a loop detection function.

FIG. 4 is a block diagram showing a schematic configuration of the transmission / reception circuit according to this embodiment. The transmitter / receiver circuit 30
Includes a transmitter and a receiver, and the transmitter is a PH
The Y state machine 31, the loop detection bit string register 32, the dilution generation circuits 33 and 38, the multiplexers 34 and 40, and the transmitters 35 and 41 are provided, and the receiver includes the receivers 36 and 42 and the loop detection bit string. The detection circuits 37 and 43 and the comparison circuit 39 are provided.

PHY in the transmitting / receiving circuit 30 shown in FIG.
State machine 31, Dilution generation circuit 33
38, multiplexers 34/40, transmitters 35/41,
The receivers 36 and 42 are the PHY state machine 11 and the Dilu in the transceiver circuit 10 shown in FIG. 1, respectively.
section generation circuit 12, multiplexer 15, transmitter 1
6 and 19 and the receivers 17 and 20 have the same configuration, and the description thereof will be omitted.

When transmitting the arbitration signal from the transmission / reception circuit 30, the PHY state machine 31 sends the control signal in the format F20 for transmitting the dilution signal between the transmission of the arbitration signal, as shown in FIG. 5 (a). When transmitting the loop detection bit string and further transmitting the loop detection bit string, the multiplexers 34 and 40 are controlled so as to transmit the control signal in the format F21 for transmitting the loop detection bit string during a part of the period for transmitting the dilution signal. .

The loop detection bit string register 32 stores the loop detection bit string and also stores the loop detection bit string in the multiplexers 34 and 40 and the comparison circuit 3.
Send to 9. It is desirable that the loop detection bit string is unique to each node in order to identify each node and does not overlap with the loop detection bit string of each node. For example, as shown in FIG.
EUI-64 (Extend
ed Unique Identifier, 64bit) and other node-specific identifiers stored in ROM (Read Only Memory)
It is desirable to transfer the data from the loop detection bit string register 32 to the loop detection bit string register 32 to use as a loop detection bit string.

Loop detection bit string detection circuits 37 and 43
Among the received signals, it checks whether or not the signal in the dilution period includes the loop detection bit string, and when detecting the loop detection bit string, transmits the detected loop detection bit string to the comparison circuit 39 and To the multiplexers 40 and 34 of the respective ports.

The comparison circuit 39 compares its own loop detection bit string from the loop detection bit string register 32 with the loop detection bit string received from the loop detection bit string detection circuits 37 and 43, and the comparison result is obtained. PHY
It is transmitted to the state machine 31.

The PHY state machine 31 uses the comparison circuit 39.
PHY state machine 3 when receiving the comparison result from
The process 1 will be described with reference to FIG. When the loop detection bit string is larger than the received loop detection bit string, the multiplexer 40 is configured to transmit the loop detection bit string from a port different from the port that receives the loop detection bit string. Control 34 (step S10).

If the loop detecting bit string is smaller than the received loop detecting bit string, the multiplexer 40 is arranged to transmit the received loop detecting bit string from a port different from the receiving port.・ 3
4 is controlled (step S11). Further, thereafter, the multiplexers 40 and 34 are controlled so as not to transmit the loop detecting bit string of itself from the received port (step S12).

Then, the self-loop detection bit string is
If it is equal to the received loop detection bit string, it is determined that a loop has been detected (step S13).

By the way, in the case of the OP i.LINK (registered trademark) standard, if the transmission / reception circuit does not receive a signal from a certain port for a predetermined period, the connection of the port is disconnected. Therefore, when a loop is detected in step S13, the continuous signal F is sent to either the port that has transmitted the loop detection bit string or the port that received the loop detection bit string.
By stopping the transmission of No. 20, the connection of the port that stopped the transmission is disconnected, and the loop is eliminated (step S14).

It is assumed that the three nodes N1 to N3 having the transmission / reception circuit 30 having the above configuration are connected as shown in FIG. 7 (a). In this state, each node N1 to N3
As shown in the format F20 of FIG. 5, the transmitter / receiver circuit 30 therein selects the arbitration signal from the PHY state machine 31 by the multiplexers 34 and 40 at the timing of transmitting the arbitration signal, and the data to be transmitted is If there is not, and it is not the timing to transmit the arbitration signal, the multiplexer 15 selects the random data code from the dilution generating circuits 33 and 38, and the transmitter 35.
1 to the partner node.

Next, consider the case where the node N3 is connected to the node N1 and the topology is changed as shown in FIG. 7B. At this time, the network is initialized in the BUS_RESET phase, and parent / child determination between nodes is performed in the TREE_ID phase.

At this time, the PHY state machine 31 of the transmission / reception circuit 30 in each of the nodes N1 to N3 stores its own loop detection bit string in the format F21 shown in FIG. 5B, and stores one or both of them. Send to port. Next, the transmission / reception circuit 30 in each of the nodes N1 to N3
When the signal storing the loop detecting bit string is received, the loop detecting bit string detecting circuits 37 and 43 detect the loop detecting bit string, and the comparing circuit 39 compares it with its own loop detecting bit string, and the PHY state machine. At 31, the processing is performed based on the magnitude relation, as shown in FIG.

For example, the loop detection bit string of the node N1 is 00, the loop detection bit string of the node N2 is 01,
It is also assumed that the loop detection bit string of the node N3 is 10 and the loop detection bit string 10 is transmitted from the node N3 to the node N2.

In this case, since the received loop detection bit string 10 is larger than the loop detection bit string 01 of its own, the node N2 transmits the received loop detection bit string 10 to the node N1 different from the node N3. To do. Next, in the node N1, the loop detection bit string 10 received from the node N2 is its own loop detection bit string 00.
Is larger than the received loop detection bit string 10
To the node N3 which is different from the node N2.

Next, the node N3 determines that a loop is detected because the loop detection bit string 10 received from the node N1 is the same as the loop detection bit string 10 of its own. Then, the node N3 stops transmitting a continuous signal to either the node N2 that has transmitted its own loop detection bit string 10 or the node N1 that has received its own loop detection bit string 10 and The connection with the node N2 or the connection between the node N3 and the node N1 is disconnected, and the loop state is eliminated.

Therefore, the transmitting / receiving circuit 30 of this embodiment is
A loop detection bit string is transmitted during a part of the transmission period of the dilution signal, and one of the loop detection bit strings is detected for loop detection based on the magnitude relationship between the received loop detection bit string and its own loop detection bit string. A loop state can be detected by transmitting from a port different from the port that received the bit string.

Further, when the loop state is detected, by stopping the transmission of the continuous signal of either the port that has transmitted the loop detection bit string of its own or the port that has received it,
The loop state can be released easily.

When the received loop detecting bit string is larger than the loop detecting bit string of its own, some nodes communicating through the received port have a loop larger than the loop detecting bit string of their own. Since there is a node having the detection bit string, the loop state cannot be detected by its own loop detection bit string.

Therefore, as shown in step S12 in FIG. 8, when the received loop detection bit string is larger than the loop detection bit string of its own, from the received port, the loop detection bit string of the self is detected thereafter. By not transmitting, the transmission period of the dilution signal can be restored to the original period as shown in FIG.
This allows Dilutio to detect loop conditions.
It is possible to prevent the effect of n from decreasing.

In the present embodiment, the larger loop detection bit string is transmitted, but on the contrary,
The effect of this embodiment can be obtained by transmitting the smaller loop detection bit string.

Further, in the IEEE 1394 standard, as described above, PAs are connected between nodes forming a loop state.
Since REN_NOTIFY is not sent / received,
The arbitration signal transmitted and received is BUS_RE.
Only SET and IDLE (see FIGS. 16 and 17).

Therefore, as the arbitration signal,
Even if the PHY state machine 31 controls the multiplexers 34 and 40 so as to transmit the loop detection bit string only when transmitting BUS_RESET and IDLE,
The operation and effect of this embodiment can be realized. Also, BU
Di except when sending S_RESET and IDLE
As shown in FIG. 5A, the transmission period of the rotation signal can be returned to the original state, so that it is possible to prevent the effect of dilution from being reduced due to the detection of the loop state.

As described above, the loop in the topology of the network occurs only when the topology changes due to the addition / deletion of nodes, and the IEEE 139
In the four standards, BUS_RESET is always transmitted and received in this case. Further, as described above, the end of the TREE_ID phase is limited only when there is no loop or when the loop is cleared.

Therefore, the PHY is set so that the loop detection bit string is transmitted only during the period from the transmission / reception of BUS_RESET to the end of the TREE_ID phase.
Even if the state machine 31 controls the multiplexers 34 and 40, the operation and effect of this embodiment can be realized. Further, except for the above period, the transmission period of the dilution signal can be returned to the original period as shown in FIG. 5 (a), and therefore, it is possible to prevent the reduction of the effect of dilution for detecting the loop state. You can

[Third Embodiment] Next, still another embodiment of the present invention will be described with reference to FIGS. Note that configurations having the same functions as the configurations described in the above-described embodiments are given the same reference numerals, and description thereof will be omitted.

FIG. 9 is a block diagram showing a schematic configuration of the transmission / reception circuit of this embodiment. Transmitting / receiving circuit 5 of this embodiment
0 is greater than that of the transceiver circuit 30 of the embodiment shown in FIG.
The configuration is different except that a counter 52 that counts the number of ports for which parent-child determination has been completed is added, and that a PHY state machine 51 that performs a processing operation different from the processing operation of the PHY state machine 31 is provided. .

FIG. 10 is a flowchart showing a processing operation for loop detection in the PHY state machine 51 of the transmission / reception circuit 50. The processing operation shown in FIG. 10 is different from the processing operation shown in FIG. 8 in that PARENT_N is transmitted from the port to which the loop detection bit string is to be transmitted before steps S10 and S11 for transmitting the loop detection bit string.
Step S for determining whether or not OTIFY is received
20. S21 is added, and the other steps are the same.

In the judgment steps S20 and S21, PA is transmitted from the port to which the loop detection bit string is to be transmitted.
If RENT_NOTIFY is not received, the following transmission processing steps S10 and S11 are performed, and if RENT_NOTIFY is received, the transmission processing steps S10 and S11 are not performed and the process ends.

The PHY state machine 51 uses the PA
The counter 52 counts the number of ports for which parent-child determination is completed by receiving RENT_NOTIFY and transmitting CHILD_NOTIFY from the received port, and the counted number is (the number of ports owned by itself) -1.
At the time when (1 in the case of FIG. 9) is reached, it is determined that its own node does not form a loop state, and the next BUS
Until _RESET is transmitted / received, the multiplexers 34 and 40 are controlled so that the loop detection bit string is not transmitted from the remaining one port whose parent / child determination has not been completed.

As described above, when a loop is formed, PARENT_NOTIFY is sent from the nodes that form the loop.
Is not transmitted, the problem occurs that the SELF_ID phase does not end. Conversely speaking, PARENT_NO
It can be said that the node transmitting TIFY is not the node forming the loop.

Therefore, in the transmitting / receiving circuit 50 having the above structure, the port that receives PARENT_NOTIFY is
Even if the PHY state machine 51 controls the multiplexers 34 and 40 so as not to transmit the loop detection bit string, the same effect as that of the transmission / reception circuit 30 of the embodiment shown in FIG. 4 can be obtained.

Also, after receiving PARENT_NOTIFY, PAR is transmitted until BUS_RESET is transmitted / received.
Since the loop detection bit string is not transmitted to the port that has received ENT_NOTIFY, the transmission period of the dilution signal can be returned to the original period as shown in FIG. This allows Di to detect the loop state.
It is possible to prevent the effect of solution from decreasing.

When the count number of the counter 52 becomes (the number of ports owned by itself) -1, it can be judged that its own node does not form a loop state, so that the parent-child decision is completed. By not sending the loop detection bit string from the remaining one port, the Dilu
As shown in FIG. 5A, the transmission period of the action signal is
Can be undone. As a result, it is possible to prevent the effect of dilution from being reduced due to the detection of the loop state.

[Fourth Embodiment] Next, still another embodiment of the present invention will be described with reference to FIGS. 11 and 12. Note that configurations having the same functions as the configurations described in the above-described embodiments are given the same reference numerals, and description thereof will be omitted.

FIG. 11 is a block diagram showing a schematic configuration of the transmission / reception circuit of this embodiment. The transmission / reception circuit 60 of the present embodiment is different from the transmission / reception circuit 30 of the embodiment shown in FIG. 4 in that a loop detection start decision circuit 82 for deciding the timing to start the detection of a loop is added, and that of the PHY state machine 31. P that performs a processing operation different from the processing operation
The configuration is different except that the HY state machine 61 is provided, and other configurations are the same.

The PHY state machine 61 uses the BUS_R
PARENT_NOTI, whether ESET was sent or received
Loop detection start determination circuit 82 determines whether or not FY has been transmitted / received.
And the loop detection start determination circuit 82 receives the loop detection start determination. Upon receiving the loop detection start decision, the PHY state machine 61 performs the same loop detection operation as that of the PHY state machine 31.

FIG. 12 is a flow chart showing the processing operation in the loop detection start decision circuit 82. First, B
When the PHY state machine 61 notifies that the US_RESET has been transmitted / received, the processing operation is started (step S31).

Next, it is determined whether PARENT_NOTIFY has been transmitted or received (step S32). PARE
When sending and receiving NT_NOTIFY, BUS_R
After waiting until the ESET is sent and received again, step S
Return to 32. In the case of a normal bus connection without a loop, the standby state of step S32 is entered.

When PARENT_NOTIFY is not transmitted / received, it is determined whether BUS_RESET is transmitted / received again (step S34). BUS_RE
If the SET is not transmitted / received, the process returns to step S32. If the SET is transmitted / received, it is determined that a loop may exist, and the PHY state machine 61 is notified to start the loop detection processing operation. To do.

In the IEEE 1394 standard, when a loop is formed, PARENT_NOTIFY is not transmitted, IDLE is transmitted / received, BUS_RESET is transmitted / received after a predetermined time elapses, and thereafter, IDLE and BUS_RESET are transmitted until the loop is cleared. Will be repeated.

Therefore, the transmitting / receiving circuit 60 having the above-mentioned configuration is
After sending and receiving US_RESET, PARENT_NO
BUS_RESET again without sending and receiving TIFY
Even when it is determined that a loop may exist and the processing operation of loop detection is started only when the transmission / reception is performed, the same effect as that of the transmission / reception circuit 30 of the embodiment shown in FIG. 4 can be obtained. You can

Further, only in the above case, the loop detection processing operation is started and the loop detection bit string is transmitted. Therefore, in other cases than the above case, the loop detection bit string is not transmitted and the transmission period of the dilution signal is not transmitted. Is shown in FIG.
Can be undone as shown in. As a result, it is possible to prevent the effect of dilution from being reduced due to the detection of the loop state.

[Fifth Embodiment] Next, still another embodiment of the present invention will be described with reference to FIGS. Note that configurations having the same functions as the configurations described in the above-described embodiments are given the same reference numerals, and description thereof will be omitted.

FIG. 13 is a block diagram showing a schematic configuration of the transmission / reception circuit of this embodiment. The transmission / reception circuit 70 of this embodiment is different from the transmission / reception circuit 30 of the embodiment shown in FIG. 4 in that flag generation circuits 72 and 73 and a flag detection circuit 74.
-75 is added, and a PHY state machine 71 that performs a processing operation different from the processing operation of the PHY state machine 31 is provided, and other configurations are the same.

The flag generation circuits 72 and 73 generate a flag signal which is a predetermined bit string, and the multiplexer 34
・ Send each to 40. Multiplexer 34/40
Under the control of the PHY state machine 71, the arbitration signal from the PHY state machine 71 and the Di from the dilution generation circuit 33 are transmitted so as to transmit the continuous signals of the formats F30 to F32 shown in FIG.
selection signal (random data code), a flag signal from the flag generation circuit 72, and a loop detection bit string from the loop detection bit string register 32.

Further, the flag detection circuits 74 and 75 detect the presence or absence of a flag signal from the received signal and notify the PHY state machine 71. PHY state machine 71
If the received signal does not have a flag signal, it is determined that the received signal does not have a loop detection bit string, and even if the comparison circuit 39 notifies the loop detection bit string of the magnitude relationship, the notification is given. Ignore. If there is a flag signal, the PHY state machine 71 determines that the received signal has a loop detection bit string, and performs a loop detection process similar to that of the transmission / reception circuit 30 shown in FIG.

In the transmission / reception circuit 70 having the above structure, the PH
The Y state machine 71 controls the multiplexers 34 and 40 to execute the format F3 shown in FIGS.
A continuous signal of 0 · F31 is transmitted from the transmitters 35/41.

That is, at the timing of transmitting the arbitration signal, the arbitration signal from the PHY state machine 71 is selected, and if there is no data to be transmitted and it is not the timing to transmit the arbitration signal, the flag is set at a predetermined timing. The flag signals from the generation circuits 72 and 73 are selected, the loop detection bit string is selected from the loop detection bit string register 32, the random data code is selected from the dilution generation circuit 33, and the selected random data code is transmitted to the outside.

Here, the flag signal is, for example, OP
When this embodiment is applied to a transmission / reception circuit of the i.LINK (registered trademark) standard, an OP i.LINK as shown in FIG.
It must be composed of bit strings that are not generated by the algorithm defined in the (registered trademark) standard, and when applied to other communication methods, it is a bit string that is not generated by the pseudo-random number generation algorithm adopted in that communication method. Needs to be configured.

When the transmission / reception circuit 70 receives a signal, the flag detection circuits 74 and 75 detect the presence / absence of a flag signal from the received signal, and the PHY state machine 71.
To notify. When the received signal does not include the flag signal, the PHY state machine 71 determines that the received signal does not include the loop detection bit string, and the comparison circuit 39
Even if the relationship between the loop detection bit strings is notified from, the notification is ignored. On the other hand, if there is a flag signal, the PHY state machine 71 determines that the received signal has a loop detection bit string, and performs loop detection processing similar to that of the transmission / reception circuit 30 shown in FIG.

By the way, assuming that the node A having the transmission / reception circuit of the above-described embodiment having the loop detection function is connected to the node B having the transmission / reception circuit not having the loop detection function, the node B becomes as shown in FIG. The continuous signal of the format F30 shown in (a) is transmitted to the node A. At this time, if a part (random data code) of the Direction signal happens to coincide with the loop detection bit string of the node A, the node A mistakenly recognizes that a loop exists and disconnects any port of the node A. May occur.

At this time, by using the transmission / reception circuit 70 of the present embodiment, the loop detection bit string becomes Dilut.
A loop signal is detected by transmitting a flag signal indicating whether the signal is included in the signal of the transmission period of the ion signal during a predetermined period within the transmission period of the dilution signal and detecting the presence or absence of the flag by the flag detection circuits 74 and 75. Since the processing of (1) is executed or stopped, it is possible to prevent the random bit string of the dilution from being erroneously recognized as the loop detection bit string.

If there is at least one node that does not have the loop detection function among the nodes forming the loop, the node that does not have the loop detection function does not transmit the loop detection bit string. After that, a normal loop cannot be detected.

Therefore, in the transmission / reception circuit 70 having the above-mentioned configuration, the PHY state machine 71 has the flag detection circuit 74.
When the flag is not detected by 75, it is determined that the node connected to the transmission / reception circuit 70 does not have the loop detection function, and the loop detection bit string is not transmitted thereafter. If the control is performed as described above, it is possible to prevent the reduction of the effect of dilution because the loop state is detected.

In the above embodiment, as shown in FIGS. 8 and 10, when the loop detecting bit string is smaller than the received loop detecting bit string when performing the loop detecting operation. , The process for controlling the multiplexer is performed so that the received loop detection bit string is transmitted from a port different from the received port (step S11). At this time, it is stored in the loop detection bit register 32. You may add the process which updates a loop detection bit string to the received loop detection bit string. In this case, since the loop detection bit strings of the nodes forming the loop are all the same, the nodes forming the loop can be easily found.

[0140]

As described above, the data communication method of the present invention is a data communication method for transmitting and receiving a data signal and a control signal between nodes, and when transmitting the control signal, a predetermined interval is used. While sending the control code with
The information code is transmitted at a predetermined timing other than the timing of transmitting the control code.

As a result, when transmitting the control signal, the information code can be transmitted / received together with the control code, so that the node can transmit / receive various information.
For example, various problems that occur when the network is automatically reconfigured can be solved by various information transmitted and received.

For example, the information code may be a code requesting reconfiguration of the network. in this case,
By transmitting a code for requesting network reconfiguration as an information code, it is possible to determine whether or not each node may immediately perform network reconfiguration. For example,
The effect that the network can be reconfigured after processing that should be performed immediately, such as data transfer that requires real-time processing, is completed.

Further, the information code may be an identification code for identifying a node. In this case, the node is
By receiving the own identification code transmitted from a certain port from another port, it is possible to detect that a loop is formed.

As described above, the transmission / reception circuit of the present invention is a transmission / reception circuit provided in a node for transmitting / receiving a data signal and a control signal between the nodes, and the control code and the control signal serving as the control signal are A code generator that generates an information code, a transmitter that has a controller that transmits any one of the control code and the information code generated by the code generator, and the received signal, It is a configuration including a receiving unit having a determination unit that determines whether the control code or the information code.

According to this, various information can be transmitted and received by transmitting and receiving the information code. For example, various problems that occur when the network is automatically reconfigured are determined by the various information transmitted and received. The effect is that it can be solved.

For example, the information code may be a code for requesting network reconfiguration. in this case,
By transmitting a code requesting network reconfiguration as an information code, it is possible to judge whether each transmitting / receiving circuit can immediately perform network reconfiguration. For example, in the case of data transfer requiring real-time property, What
The effect is that the network can be reconfigured after the processing that should be performed immediately is completed.

Further, the information code may be an identification code for identifying the transmitting / receiving circuit. In this case, the transmission / reception circuit has an effect that it can detect that its own transmission / reception circuit is one of the nodes forming the loop by receiving its own identification code transmitted from a certain port from another port. .

Further, as described above, the transmission / reception circuit of the present invention has a plurality of ports connected to other transmission / reception circuits, the identification code received from a port among the plurality of ports, and the self-identification code. The control unit further includes a comparing unit that compares the identification code of No. 1 with that of the received identification code that is larger or smaller than its own identification code. In the other case, the received identification code is transmitted from a port different from the received port, and if the values are equal, it is determined that a loop is formed with another transmission / reception circuit. Is.

As a result, it is possible to detect that it is one of the transmission / reception circuits forming a loop.

Further, as described above, in the transmitting / receiving circuit of the present invention, in the above configuration, when the control section transmits the received identification code, it does not transmit its own identification code from the received port. Control to control not to transmit the self-identification code or the received identification code from the port that received the control code that determines the master-slave relationship with other transmission / reception circuits, or other than the port for which the master-slave relationship has been determined. When the number of remaining ports is one, the configuration is such that the identification code of itself or the received identification code is not transmitted from any of the ports.

As a result, there is an effect that the waste of the transmission can be omitted. In addition, since the random data code can be transmitted because the information code is not transmitted, it is possible to suppress the reduction of the effect of the dilution by transmitting the information code.

Further, as described above, the transmission / reception circuit of the present invention has its own configuration when the control unit determines that it forms a loop with another transmission / reception circuit. The loop is released by not transmitting a signal to the port that has transmitted the identification code or the port that has received the identification code.

For example, by applying the transmission / reception circuit to the specification that the connection of the port is disconnected when the signal is not received from the certain port for a predetermined period like the OP i.LINK (registered trademark) standard. , The effect of being able to automatically eliminate the loop.

Further, as described above, the transmission / reception circuit of the present invention has the above-mentioned configuration only when the control unit initializes the network or determines the master-slave relationship with another transmission / reception circuit. The identification code is transmitted as the information code.

According to this, by transmitting the identification code only when the loop is formed or when the formation of the loop causes a problem, it is possible to eliminate waste of transmission. Also, because the information code is not sent, a random data code can be sent,
It is possible to suppress the reduction of the dilution effect caused by transmitting the information code.

Further, as described above, in the transmitting / receiving circuit of the present invention, in the above structure, the code generating section further generates a flag signal for judging whether or not an information code exists, and the judging section The configuration further determines whether or not the received signal is the flag signal.

According to this, it is possible to prevent the random data code from being mistaken for the information code by using the flag signal for determining whether or not the information code exists.

Further, the information equipment of the present invention has the above-mentioned transmitting / receiving circuit as described above.

As a result, various problems that occur when the network is automatically reconfigured can be solved by the information devices transmitting and receiving various information.

Further, the information communication network of the present invention is
As described above, a plurality of information devices are connected.

As a result, various problems that occur when the network is automatically reconfigured can be solved by transmitting and receiving various information in the network.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of a transmission / reception circuit according to an embodiment of the present invention.

FIG. 2 is a block diagram showing how the topology of a network changes when a new node links.

3 is a block diagram showing a format of a continuous signal transmitted / received by the transmission / reception circuit shown in FIG.

FIG. 4 is a block diagram showing a schematic configuration of a transmission / reception circuit according to another embodiment of the present invention.

5 is a block diagram showing a format of a continuous signal transmitted / received by the transmission / reception circuit shown in FIG.

FIG. 6 is a block diagram showing an EUI-64 format suitable for a loop detection bit string.

FIG. 7 is a block diagram showing a state in which a network topology is changed by a new node linking and a loop is generated.

8 is a flowchart showing a processing operation of loop detection in the PHY state machine of the transmission / reception circuit shown in FIG.

FIG. 9 is a block diagram showing a schematic configuration of a transmission / reception circuit according to still another embodiment of the present invention.

10 is a flowchart showing a processing operation of loop detection in the PHY state machine of the transmission / reception circuit shown in FIG.

FIG. 11 is a block diagram showing a schematic configuration of a transmission / reception circuit according to still another embodiment of the present invention.

12 is a flowchart showing a processing operation in a loop detection start determination circuit of the transmission / reception circuit shown in FIG.

FIG. 13 is a block diagram showing a schematic configuration of a transmission / reception circuit according to still another embodiment of the present invention.

14 is a block diagram showing a format of a continuous signal transmitted / received by the transmission / reception circuit shown in FIG.

FIG. 15 is a timing chart for explaining the DS-Link encoding method.

FIG. 16 is a table showing line states of arbitration signals transmitted in the physical layer in the IEEE 1394 standard and their meanings.

FIG. 17 is a table showing the line states of arbitration signals received at the physical layer in the IEEE 1394 standard and their meanings.

FIG. 18 is a block diagram showing a connection state of nodes in a certain network.

19A and 19B are block diagrams showing formats of a transmission signal and a reception signal, where FIG. 19A shows a conventional system and FIG. 19B shows a dilution system.

20 is a block diagram showing a pseudo-random number generation circuit for generating random data used in Dilution, which is defined in the OP i.LINK (registered trademark) Ver. 1.0 standard.

[Explanation of symbols]

10 Transmitting / Receiving Circuit 11 PHY State Machine (Code Generation Unit, Control Unit) 12 Dilution Generation Circuit 13 BUS_RESET Generation Request Generation Circuit (Code Generation Unit) 14 BUS_RESET Standby Request Generation Circuit (Code Generation Unit) 15 Multiplexer 18 Direction Discrimination Circuit (Discrimination Unit) ) 30 transmission / reception circuit 31 PHY state machine (code generation unit, control unit) 32 loop detection bit string register (code generation unit) 33 dilution generation circuit 34 multiplexer 37 loop detection bit string detection circuit (determination unit) 38 dilution generation circuit 39 comparison Circuit (comparing unit) 40 Multiplexer 43 Loop detection bit string detection circuit (discriminating unit) 50 Transmission / reception circuit 51 PHY state machine (code generation unit, control unit) 52 Counter 60 Transmission / reception Circuit 61 PHY state machine (code generation unit, control unit) 62 Loop detection start determination circuit 70 Transmission / reception circuit 71 PHY state machine (code generation unit, control unit) 72 Flag generation circuit (code generation unit) 73 Flag generation circuit (code generation) Part) 74 flag detection circuit (discrimination part) 75 flag detection circuit (discrimination part) N1 to N3 nodes

Claims (12)

[Claims] 1. A data communication method for transmitting and receiving a data signal and a control signal between nodes, wherein when transmitting the control signal, a control code is transmitted at a predetermined interval and the control code is transmitted. A data communication method, characterized in that the information code is transmitted at a predetermined timing other than the timing at which the information code is transmitted. 2. The data communication method according to claim 1, wherein the information code is a code for requesting reconfiguration of the network or an identification code for identifying a node. 3. A transmission / reception circuit provided in a node for transmitting and receiving a data signal and a control signal between nodes, the code generation section generating a control code and an information code to be the control signal, and the code. A transmitter having a controller transmitting one of the control code and the information code generated by the generator, and whether the received signal is the control code or the information code. And a receiving unit having a determining unit for determining 4. The transmission / reception circuit according to claim 3, wherein the information code is a code requesting reconfiguration of the network. 5. The transmission / reception circuit according to claim 3, wherein the information code is an identification code for identifying the transmission / reception circuit. 6. A control unit further comprising: a plurality of ports connected to another transmission / reception circuit; and a comparison unit for comparing an identification code received from a port of the plurality of ports with its own identification code. If the received identification code is larger or smaller than its own identification code, in one case its own identification code, in the other case the received identification code is different from the received port. 6. The transmission / reception circuit according to claim 5, wherein the transmission / reception circuit determines that a loop is formed with another transmission / reception circuit when the values are equal to each other. 7. The control unit, when transmitting the received identification code, controls so as not to transmit its own identification code from the received port, and a control code for determining the master-slave relationship with another transmission / reception circuit. It controls not to transmit its own identification code or the received identification code from the received port, or if there is one port other than the port for which the master-slave relationship has been determined, the self-identification The transmission / reception circuit according to claim 6, wherein control is performed so that the identification code or the received identification code is not transmitted. 8. When the control unit determines that a loop is formed with another transmission / reception circuit, it does not transmit a signal to the port that transmitted its own identification code or the port that received it. 8. The transmitting / receiving circuit according to claim 6, wherein the loop is released by doing so. 9. The control unit, when initializing the network,
Alternatively, the transmission / reception circuit according to any one of claims 5 to 8, wherein the identification code is transmitted as the information code only when the master-slave relationship with another transmission / reception circuit is determined. 10. The code generator further generates a flag signal for determining whether or not an information code is present, and the determiner further determines whether or not the received signal is the flag signal. The transmission / reception circuit according to claim 3, wherein the transmission / reception circuit is a transmission line. 11. An information device comprising the transmission / reception circuit according to any one of claims 3 to 10. 12. An information communication network to which a plurality of information devices according to claim 11 are connected.