JP2002319958A - Data repeater and multiplex communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve reliability in data relay of a multiplex communication system. SOLUTION: A data repeater 4 provided among a plurality of multiplex communication lines 21 to 23 is provided a buffer 431 that temporarily holds received data before transmitting the received data in each type of data, and also, a plurality of buffers are allocated about a portion of data types. A data controller 44 for control is set so as to designate a buffer 431 for identifying the type of the received data and writing the type of the received data and also to confirm the presence/absence of data in each buffer 431 to transfer the data to a prescribed a relay destination. Furthermore, data are exchanged between buffers 431 so that the first received data among pieces of data being the same data type can be stored in a prescribed buffer 431, and confirmation of the presence/absence of the data is performed only about the prescribed buffer 431. Skipping in a transfer mode is also inhibited between pieces of data of the same type so that buffers 431 can be overwritten only by the latest data of the same type.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a data relay device and a multiplex communication system.

[0002]

2. Description of the Related Art In recent years, the advancement of computer technology has led to the advancement of information communication. For example, in an automobile, the amount of information exchanged between control units for controlling mounted electric components and the like has been increasing. It is growing rapidly. Therefore, multiplex communication systems are being adopted to reduce the number of wire harnesses for transmitting information. In the multiplex communication system, a communication node such as a control ECU for transmitting and receiving data is connected to a common multiplex communication line, and data communication is performed between the communication nodes via the multiplex communication line. The data is configured to include data type information and the like together with the data body, so that the received communication node can understand the contents of the data. In the case of the above-mentioned automobiles with various types of control, in order to perform data communication efficiently,
As shown in FIG. 32, a plurality of communication systems 9 including multiplex communication lines 921, 922, and 923 and nodes 931 and 932 connected thereto according to a difference in required communication speed and the like.
Communication systems 911 to 9 belonging to 11,912,913
Some of the communication between the nodes 931 and 932 having different 13 is performed via the data relay device 94. In the illustrated example, an engine ECU 931 controls a power system such as an engine according to the shift position of the shift lever 81.
And a meter ECU 932 for controlling display and the like of the meter 82
Belong to different communication systems 911 and 912.

[0003] The data relay device 94 is usually provided with a reception buffer for receiving data and a transmission buffer for storing data immediately before transmission to a multiplex communication line. In order to efficiently relay a large amount of data, a buffer for temporarily holding received data before transmitting it to a multiplex communication line of a relay destination is provided for each type of data to be relayed, and a data buffer is provided. Is received, the type of the received data is identified and written into a buffer corresponding to the type (Japanese Patent Laid-Open No. 2000-24).
No. 4548). With this technology, overwriting between different types of data is prohibited, so an excellent effect that prevents any type of data from being completely lost even if the communication is congested. To play. Also, Japanese Patent Application Laid-Open No. 2000-244548 discloses an apparatus in which the priority of data is reset to alleviate data stagnation in the data relay device.

[0004]

By the way, among data, not only the latest data but also a change in data input in time series has a meaning. FIG.
In the example, the meter ECU 932 outputs “P” and “R” indicating the shift position which is one of the display units of the meter 82.
Six indicators 82 of "N""D""2""L"
1 is switched between on and off, but data on whether each indicator 821 is on or off is received from an engine ECU 931 belonging to a communication system 911 different from the meter ECU 932.

FIG. 33 shows an example of the structure of the data body of the data indicating whether the data is on or off. The shift positions from "P" to "L" correspond to one-to-one from the first bit to the sixth bit. Each bit is "1" when the light is on, and "0" when the light is off. When the driver moves the shift lever from “P” to “L” in five steps at a stretch in order to start the car, the engine ECU 931 changes the bit that becomes “1” to the next bit at each step. The moved data is transmitted from the engine ECU 931, and these data immediately enter the data relay device 94.
In such a case, if the data is replaced with the latest data due to overwriting of the buffer in the data relay device 94, there is a disadvantage that the display of the shift position is skipped in the indicator 821.

[0006] As described above, it is one idea to reset the priority to a higher priority in order to transfer such data reliably. However, if another type of data is accumulated in the transmission buffer of the data relay device 94, Eventually, the data in the buffer will be overwritten.

[0007] The present invention has been made in view of the above circumstances,
An object of the present invention is to provide a data relay device and a multiplex communication system that are highly resistant to data loss.

[0008]

According to the first aspect of the present invention, a plurality of types of data are interposed between a multiplex communication line for transmitting data including data type information together with a main body of the data. In a data relay device having a data controller for selecting a multiplex communication line to which received data is relayed and transferring received data, the data relay device temporarily holds received data before transmitting it to the multiplex communication line of the relay destination Buffers are provided for each type of data to be relayed, and a plurality of buffers are assigned to one or more data types among the data types, and the data controller identifies the type of received data, Buffer designating means for designating a corresponding buffer as a destination to which received data is to be written, and data from a buffer in which data is stored. Data transfer management means for managing the transfer of data, and the data transfer management means is configured to transfer data from a buffer of the same data type in each multiplex communication line in the order that data is written to the buffer. Set up in order.

By providing a buffer for each type of data, it is possible to prevent the buffer from being overwritten only by the latest data of the same type and from losing other types of data waiting to be transmitted due to received data. it can.

[0010] Further, as for data of a type to which a plurality of buffers are allocated, even if data is received one after another, they can be held simultaneously, and the resistance to data loss can be increased. In addition, since data transfer from the buffer is performed from the earliest when data is stored in the buffer for at least the same selected multiplex communication line, the same type of data is transferred in the data transfer from the buffer. Jumping can be reliably prevented.

According to a second aspect of the present invention, in the configuration of the first aspect of the present invention, the data transfer management means is activated at predetermined time intervals, and sequentially checks the presence / absence of data to be transmitted in the buffer. If there is, the setting is made so that data is transferred from the buffer, and whether or not there is data in the buffer of the same data type is checked first from the buffer in which the data is stored.

By sequentially checking the presence / absence of data in the buffer, the existence of data to be transmitted is reliably known from the buffer group, and the presence / absence of data in a buffer of the same data type is determined. Is first checked for the buffer in which the data is stored first, so that the data stored first can be transferred from the buffer prior to another buffer of the same data type.

According to a third aspect of the present invention, in the configuration of the second aspect of the present invention, the data transfer management means is configured to determine whether or not there is data in the buffer only for a predetermined buffer for a buffer of the same data type. And after completing the transfer of the data in the predetermined buffer corresponding to the selected multiplex communication line, the first among the data in the other buffers of the same data type Is set to move the received data to the predetermined buffer.

[0014] By ensuring that the earliest received data of the same type of data always exists in a predetermined buffer, the data to be transferred can be checked without checking the existence of data in all buffers. The presence or absence can be surely confirmed.

According to a fourth aspect of the present invention, in the configuration of the first aspect of the present invention, the buffer information for specifying a buffer storing data is included, and the order of the buffer information in which the selected multiplex communication lines are the same is determined by the buffer order. And a transmission data list, which is an order of transferring data from the buffer, and sets the data transfer management means so as to update the transmission data list in accordance with writing of data to the buffer and transfer of data from the buffer.

Since the buffer storing the data to be transferred can be known from the transmission data list without confirming the presence or absence of the data in the buffer, the data can be relayed quickly.

In addition, since the order of transferring data from the buffer is known for each multiplex communication line, data of the same data type is written to the buffer one after another, and a plurality of data of the same data type are written in the transmission data list. Is entered, the data is transferred from the buffer corresponding to one multiplex communication line, and the data is not transferred corresponding to the other multiplex communication line. It is known that the buffer storing the data to be transferred next corresponding to the line is the buffer specified by the buffer information arranged next to the buffer information of the buffer storing the transmitted data. This can prevent the same data from being transmitted by mistake.

According to a fifth aspect of the present invention, in the configuration of the fourth aspect, the transmission data list is provided with an initial value for each multiplex communication line based on buffer information for specifying a buffer and the transfer destination table. The data transfer management means does not need to transmit the management information in accordance with the transfer of the data from the buffer. Is set to switch to the information indicating that

With the buffer storing the data to be transferred, the transfer progress of the data for each multiplex communication line can be managed in a unified manner, so that the data stored in the buffer is transferred to the selected multiplex communication line. , It is possible to easily know whether or not all of them are completed, and it is possible to reduce the control burden.

According to a sixth aspect of the present invention, a multiplex communication system includes the data relay device according to the first to fifth aspects and a plurality of communication systems in which communication nodes for transmitting and receiving data are connected to the multiplex communication line. With this configuration, it is possible to construct a multiplex communication system that does not impair the reliability of data communication due to the loss of relay data.

[0021]

FIG. 1 shows a data relay device and a multiplex communication system according to a first embodiment of the present invention. The multiplex communication system has a plurality (3 in the example in the figure).
And the data relay device 4. Each of the communication systems 11 to 13 includes a multiplex communication line 21,
The communication nodes 31, 32, and 33 are connected to the communication nodes 22, 23, and data is transmitted and received between the communication nodes 31 to 33 using a predetermined protocol. Communication node 3
1 to 33 belong to at least one of the communication systems 11 to 13.

FIG. 2 shows an example of the frame structure of the data. This is the BEAN (Body Elect)
3 is a frame structure in the RONICS Area Network protocol. In the following description, data communication will be described as being based on the BEAN protocol. SOF (Start Of Frame)
e) indicates the start of a frame, and 1 bit is allocated. The PRI (Priority) is an area indicating the priority of the frame, and 4 bits are allocated. “1” has a higher priority than “0”. The data relay device 4 and the communication nodes 31 to 33 transmit high-priority data and transmit other data when data collision occurs on the multiplex communication lines 21 to 23 in each of the communication systems 11 to 13. Is aborted. ML (Message Length) is an area indicating the length of the following message part, and DID and MID constituting the message part are each 1 as described later.
byte, and DATA has a variable length.
The number of bytes of A + 2.

The beginning of the message part is DID (Dest
location ID), which is an area indicating the destination node ID of the frame. MID (Message
eID) is an area representing a message ID, and is assigned 8 bits. The MID is assigned for each type of data, and specifies the type of data represented by the content of DATA, which will be described later, which is the main body of the data. Types of data exchanged by communication include an engine speed and the like, and MID is given to each of them, for example, as shown in FIG. In the example shown in the figure, DATA of communication data with MID = 08h indicates engine speed, DATA of communication data with MID = A5h indicates vehicle speed, and DATA of communication data with MID = DDh is a power window switch. Represents the state of. DATA is allocated to 1 to 11 bytes in a data body area.

After the DATA, a CRC (Cyclic)
Redundancy Characters), EO
M (End Of Message), RSP (Res
pounce) follows. The CRC is a communication error check area to which 8 bits are assigned. The CRC checks the communication error by the communication node substituting the contents from PRI to DATA into a predetermined mathematical expression, writing the result of the bit operation, and comparing the received communication node with the received data. EOM indicates the end of the message with a predetermined bit string, and is assigned 8 bits. RSP is an area where the communication node that has received the data writes a response.
Two bits are allocated. The result indicating whether or not the content of the frame has been correctly interpreted by the receiving communication node is written in the RSP, and the communication node that has transmitted the data determines whether or not retransmission is necessary based on the result. The end of the data is EOF (End Of Frame), which indicates the end of the frame by a predetermined bit string, and is assigned 6 bits.

Each of the multiplex communication lines 21 to 23 is connected to the data relay device 4.
33 are relayed to communication nodes 31 to 33 belonging to different communication systems 11 to 13.

The data relay device 4 is provided with the multiplex communication lines 21 to 2
3 is constituted by a communication IC serving as an interface with the control unit 3 and a microcomputer for control, and is represented by functional blocks in the figure.
12, 413, transmission buffers 421, 422, 423,
It includes a buffer group 43, a data controller 44, a transfer destination table 45, and the like.

The receiving buffers 411 to 413 and the transmitting buffers 421 to 423 are provided corresponding to the respective multiplex communication lines 21 to 23. The reception buffers 411 to 413 receive data transmitted from the multiplex communication lines 21 to 23, and the transmission buffers 421 to 423 are written with data to be transmitted. Reception buffers 411 to 413 and transmission buffer 4
21 to 423 are constituted by the communication IC. Note that the data communication function may be incorporated as software executed on a CPU constituting a microcomputer. In this case, the reception buffers 411 to 413 and the transmission buffers 421 to 423 are allocated on a RAM constituting the microcomputer.

The buffer group 43 includes a plurality of buffers 431. Each buffer 431 temporarily stores data received by the reception buffers 411 to 413 before transferring the data to the transmission buffers 421 to 423 as described later in detail. Has become. At least one buffer 431 is assigned to the MID of the data to be relayed, and each buffer 431 is dedicated to one MID. Among these, a plurality of buffers 431 are allocated to a specific MID, and a plurality of data of the same MID received successively can be held simultaneously. The buffer 431 has, for example, five types of data to be transferred, and allocates three buffers for one type of data and one for the other type.
If buffers are allocated one by one, the buffer 431
Are prepared.

In the following description, the buffer 431 is appropriately represented as a buffer n (n = natural number) in a one-to-one correspondence with the MIDs to be relayed.
MID buffer 4 to which a plurality of buffers 431 are allocated
For 31, individual buffers 431 are stored in buffer n
(K) is identified as (k) (hereinafter, k is referred to as the number of stages). In the case of a data type in which a plurality of buffers are allocated, the buffer n refers to the entire buffer n (k). For example, as shown in FIG. 4, buffer 1 is for writing data with MID = 01h, buffer 2 is for writing data with MID = 5Fh, buffer 3 is for writing data with MID = 92h, and buffer 4 is for writing data with MID = 92h. (1), buffer 4
(2) and buffer 4 (3) are each MID = C
8h data, and the buffer 5 has MID =
It is for writing EBh data. The data area of the buffer group 43 is RA
M.

The data controller 44 selects the multiplex communication lines 21 to 23 to which the received data is relayed, and transfers the data to the transmission buffers 421 to 423 for the multiplex communication lines 21 to 23 to be relayed. , Receive buffer 4
In addition to controlling the data transfer from the buffer 431 to the transmission buffer 421,
423 is controlled. The data controller 44 is realized on software executed on a CPU constituting a microcomputer. The data controller 44, the reception buffers 411 to 413 and the transmission buffers 421 to 423 alternately repeat the data transfer process of the data controller 44, the reception operation of the reception buffers 411 to 413, and the transmission operation of the transmission buffers 421 to 423. Is set.

The transfer destination table 45 stores the MI of the received data.
D and transmission buffers 421 to 42 for the multiplex communication line at the relay destination
3 corresponds to the MID and the multiplex communication lines 21 to 21.
When 23 is specified, information as to whether or not the reception data of the MID should be transferred to the transmission buffers 421 to 423 for the multiplex communication lines 21 to 23 can be read. The contents of the transfer destination table 45 are stored in advance in the ROM constituting the microcomputer by the data controller 44.
Written together with the control program.

FIG. 5 shows an example of the transfer destination table 45. When the read information is "1", it indicates that the information should be transferred to the transmission buffer for the multiplex communication line. , Indicates that the data is not transferred to the transmission buffer for the multiplex communication line. In the illustrated example, the data V having MID = 01h is transferred only to the transmission buffer 422 for the second multiplex communication line.
The data W with ID = 5Fh is transferred only to the transmission buffer 423 for the third multiplex communication line, the data X with MID = 92h is transferred only to the transmission buffer 421 for the first multiplex communication line, and the data X with MID = C8h. Certain data Y is transferred to the transmission buffer 421 for the first multiplex communication line and the transmission buffer 422 for the second multiplex communication line, and the data Z having MID = EBh is transmitted to the transmission buffer 422 for the second multiplex communication line and the third buffer 422. This indicates that the data should be transferred to the transmission buffer 423 for the multiplex communication line.

The data controller 44 is provided with a buffer designating means 441 which is executed when data is transferred from the reception buffers 411 to 413 to the buffer group 43.
Is identified, and the buffer 431 corresponding to the MID is specified as a data transfer destination of the reception buffers 411 to 413.

Also, the MI composed of a single buffer 431
In the case of D, the data in the reception buffers 411 to 413 is overwritten on the buffer 431 for the MID.
For D, a buffer 43 in which no data is stored
1 is written in ascending order of the number of stages, and if there is no empty buffer 431, the buffer 431 of the buffer n (kf) of the last stage number kf is overwritten.

Thus, the received data is written into the buffer 431 for each MID corresponding to the MID.

The data controller 44 is provided with a data transfer management means 442 which is executed during data transfer processing from the buffer group 43 to the transmission buffers 421 to 423 and manages the order of data transfer.

FIGS. 6, 7, 8, and 9 show buffer group 4
3 is a flowchart showing a data transfer process from No. 3 to the transmission buffers 421 to 423. This indicates the setting contents of the data transfer management means 442. Step S10
At 0, the start buffer # = 1 and the end buffer # = N. Here, N is the number of buffers 431 constituting the buffer group 43. In step S101, n = start buffer # (= 1). In step S102, it is checked whether data has been written to the buffer n. Note that buffer # is assigned M
In the case of the ID corresponding to the ID, the determination as to whether or not the data is written is performed based on only the buffer n (1).

If it has been written, step S105
(FIG. 7). In step S105, it is confirmed whether or not the transfer destination flag is set in the data of the buffer n. The transfer destination flag is set for each of the multiplex communication lines 21 to 23. If "1" is set, it indicates that the data in the buffer n should be transferred to the multiplex communication lines 21 to 23.

If the transfer destination flag has not been set, steps S106 and S107 are executed to set the transfer destination flag. In step S106, the MID of the data in buffer n
In step S107, the transfer destination of the data in the buffer n is acquired with reference to the data transfer destination table 45, and the transfer destination flag is set in the data in the buffer n. That is, the transfer destination flag f1 is set to "1" if the transfer should be made to the transmission buffer 421 for the first multiplex communication line, and the transfer destination flag f2 if it should be transferred to the transmission buffer 422 for the second multiplex communication line. Is set to “1”, and if the data should be transferred to the transmission buffer 423 for the third multiplex communication line, the transfer destination flag f
3 is set to “1”.

When the transfer destination flag is set, step S1
08 (FIG. 8). In step S108, the transfer destination flag f1 is checked, and if "1", the process proceeds to step S109. In step S109, it is checked whether the transmission buffer 421 for the first multiplex communication line is empty. Transmission buffer 421
If is empty, the flow advances to step S110 to transfer the data in the buffer n to the transmission buffer 421. Then, in a succeeding step S111, the transfer destination flag f1 of the buffer n is set to “0”, and the process proceeds to a step S112.

In step S112, it is checked whether the transfer destination flag f2 is "1". If "1", step S1
Proceed to 13. In step S113, it is checked whether the transmission buffer 422 for the second multiplex communication line is empty. If the transmission buffer 422 is empty, the process proceeds to step S114, and the data in the buffer n is transferred to the transmission buffer 422. Then, in the subsequent step S115, the transfer destination flag f2 of the buffer n
Is set to “0”, and the process proceeds to step S116.

In step S116, it is confirmed whether or not the transfer destination flag f3 is "1". If "1", step S1
Proceed to 17. In step S117, it is checked whether the transmission buffer 423 for the third multiplex communication line is empty. If the transmission buffer 423 is empty, the process proceeds to step S118, and the data in the buffer n is transferred to the transmission buffer 423. Then, in the subsequent step S119, the transfer destination flag f3 of the buffer n
Is set to “0”, and the process proceeds to step S120 (FIG. 9).

In step S120, the transfer destination flag f1 =
It is determined whether 0 and f2 = 0 and f3 = 0.
If affirmative, it means that the data transfer to the transmission buffers 421 to 423 to be transferred has been completed, and the data in the buffer n is deleted in step S121. In the case of the MID to which a plurality of buffers 431 are assigned, the data in the buffer n (1) is deleted.

In the following step S122, it is determined whether or not the buffer n has a multi-stage structure, that is, whether or not the plurality of buffers 431 have the assigned MID. The judgment is
A buffer ♯ of a multi-stage configuration may be stored in advance and performed based on this. If affirmative, step S
Proceeding to 123, the data in buffer n (2) is transferred to buffer n
(1), and if the configuration has three or more stages, the data of each buffer n (k) is stored in the buffer n (2) such that the data of the buffer n (3) is further transferred to the buffer n (2).
To the buffer n (k). Such an operation in the buffer 431 in the same MID is a data processing substantially similar to that of the FIFO.

FIGS. 10 (A) and 10 (B) show such a case.
This indicates transfer processing from the buffer 431 to the transmission buffers 421 to 423 (421 in the illustrated example).
It is assumed that the data stored in the buffer 431 of ID = 92h and the number of stages is transferred to the transmission buffer 421 (FIG. 10).
(A)), the data of the buffer 431 is deleted, and the data of the stage number 2 and the stage number 3 are carried up sequentially, and the buffer of the stage number 3 becomes empty (FIG. 10B). In addition,
In such data movement, the physical address of the data does not actually change, but the information of the number of stages corresponding to the data may be repeated while the data storage location is kept as it is, and the two means are equivalent. .

Thereafter, the operation proceeds to step S103 (FIG. 6). If step S122 is denied, it means a single buffer configuration, and the process skips step S123 and proceeds to step S103.

In step S103, it is determined whether or not n is an end buffer #. If n ≠ end buffer #, n is incremented by one step in step S104.
Returning to step S102, the buffer n of the next buffer #
Are performed for steps S102 and S108 to S123. As described above, the buffer 431 checks the presence or absence of the data to be transferred in the order of the buffer #, and if the data is held, transfers the data to the predetermined transmission buffer 421.
To 423. When the data for the last buffer N is transferred, the data transfer processing ends.

In the data transfer process, since the transmission buffers 421 to 423 hold data and are in a transmission waiting state, steps S109, S113, and S117 are performed.
If at least one of the above is denied, step S11
0, S111, steps S114, S115, steps S118, S119 are skipped and the transfer destination flags f1, f
Either of 2 and f3 remains “1”. Therefore, step S120 is denied, step S121 is skipped, and the data in the buffer n is held as it is. That is, it waits until the transmission buffers 421 to 423 of the transfer destination become empty. In this case, in the next data transfer process, steps S105 to S106, S106
Steps S108 to S119 are executed by skipping 107, and if the transmission buffers 421 to 423 of the transfer destination are empty, the data which could not be transferred because of the previous transmission waiting is transferred.

If the state of waiting for the destination transmission buffers 421 to 423 to become empty continues, the transfer from the buffer group 43 to the transmission buffers 421 to 423 is not performed. In the meantime, if new data of the same MID as that held in the buffer 431 is received, the buffer 431 will be overwritten by the new data. However, the buffer 431 is provided for each MID of data to be relayed. Thus, overwriting by data of different data types can be avoided, so that data of a certain MID can be prevented from completely disappearing.

The data indicating whether the indicator of the shift position is on or off is stored in a buffer 4 having a plurality of stages.
If the data is transferred to the engine 31, even if the data is continuously transmitted from the engine ECU one after another, this series of data is held in the buffer 431, and the resistance to display jump can be increased. In addition, since the data received first is always present in the buffer 431 of one stage, there is no data skipping, and the above indicators are changed from "P" to "R""N""D""2""L"."
It will change in the order of.

Further, the number of buffers 431 constituting the buffer group 43 can be simplified by increasing the number of types of data to be relayed by adding a plurality of buffers for MIDs whose resistance to data loss is to be improved. It is.

Further, the data controller 44 sequentially
Since it is checked whether there is data in the buffer 431,
The existence of data to be transferred from the buffer group 43 to the transmission buffers 421 to 423 and transmitted to the multiplex communication lines 21 to 23 is reliably known.

In the buffer group 43, for example, the priority (PR
Buffer 4 of buffer # that is younger as data type of I) is higher
By assigning 31, important data can be quickly transmitted to the multiplex communication lines 21 to 23 at the relay destination.

Each time the data controller 44 starts up, the transmission buffer 421 is selected from the buffer group 43.
In the data transfer processing to 423, the data to be transmitted is checked for all MIDs to be relayed. First, for example, the data transfer processing is performed for the buffer 431 of the buffer group 43 ♯the first half buffer 431, It is also possible to set so that the data transfer process is performed for the buffer 431 in the second half of the buffer when the data is started up, and the buffer group 43 is cycled through two data transfer processes. In this case, for the buffer 431 corresponding to the important data type, the important data is promptly transmitted to the multiplex communication lines 21 to 23 at the relay destination by performing both of the two data transfer processes. Can be.

The presence of data in the buffer 431 may be confirmed by confirming only the buffer 431 of one stage in the buffer 431 having a plurality of stages as shown in FIG. 11A showing the method of the present embodiment. However, FIG.
As shown in (c), after confirming the buffer n (1), all buffers n (k) of the MID are confirmed for a part or all of the buffer 431 having a multi-stage configuration, or as shown in (C). As described above, the confirmation may be performed from the buffer n (1) to the buffer n (k) of a predetermined number of stages. Also in this case, the buffer 431 is the largest among the same MIDs.
, The priority is given to the earlier data transfer.

In this case, as shown in FIG. 12, the transmission buffers 421 to 423 (421 in the example in the figure) are configured in a plurality of stages, and data processing is performed in FIFO type.
The data may be transmitted to the multiplex communication line 21 in the order in which the data is transferred from the first line, and the data relay may be performed more smoothly.

(Second Embodiment) FIG. 13 shows a configuration of a data relay device and a multiplex communication system according to a second embodiment of the present invention. The data relay device 4A of the present embodiment
In the configuration of the embodiment, another data controller is replaced. In the data controller according to the first embodiment, the buffer checking means fixes the start buffer # and the end buffer # respectively, checks the presence or absence of data from the buffer 1 to the buffer N in order starting from the buffer 1, and performs data transfer processing. In the data controller 44A of the present embodiment, the data transfer management means 442A is set so that the start buffer # and the end buffer # are changed and the confirmation order is shifted each time the data transfer manager 442A starts up. The following description focuses on the differences from the first embodiment.

FIG. 14 shows a data transfer process from the buffer group 43 to the transmission buffers 421 to 423 in the data controller 44A of the data relay device 4A. In step S200, the start buffer # in the previous data transfer process is incremented by one. Subsequent step S2
At 01, it is confirmed whether or not the start buffer # exceeds N. If not exceeded, the end buffer # is set to the start buffer # -1. That is, in the buffer of the buffer # immediately before the start buffer #, the transmission buffer 421
To 423 goes round.

In the subsequent step S204, n is set as a start buffer #. In step S205, it is confirmed whether or not data has been written to the buffer n. If the data has been written, the data is stored in the same procedure as in FIGS. The transfer processing is performed for the written buffer n, and step S20 is performed.
Proceed to 6. If it has not been written (step S20
5) Proceed directly to step S206.

In step S206, n is the end buffer #
If n is not the end buffer #, steps S207 and S208 are executed, and then step S207 is executed.
The procedure of transition to 205 is executed, and the data transfer process is continued for the buffer 431 of the next buffer #. Steps S207 and S208 are steps for updating n to the serial number of the buffer 431 to be checked next.
Then, n is incremented by one. In step S208, it is confirmed whether or not this n is equal to or greater than N. If it is less than N, the process returns to step S205, and n incremented in step S207, that is, the buffer 431 of the next buffer #
Check if there is data for. Thus, n
Becomes large and finally reaches N. In this case, step S
From step 208, the process proceeds to step S209, where n is set to 1 and the process returns to step S205. This is because the buffer 1 is checked next to the buffer N. In this manner, the data transfer processing is executed for all N buffers 431.

In this data transfer processing, the start buffer #
The end buffer # and the end buffer # are sequentially shifted each time one search is performed, so that the degree of delay in transferring data between MIDs can be prevented from being biased. For example, in the example of FIGS. 4 and 5, the second multiplex communication line 22
Are three data V, Y and Z. Since the data V is stored in the buffer 1, the data Y is stored in the buffer 4, and the data Z is stored in the buffer 5, the data controller 44 of the first embodiment always starts checking the presence or absence of data from the buffer 1. When the transmission buffer 422 is written by the data V transferred from the device, the data Y cannot be written (see step S113). Further, when any of the data V and Y is written to the transmission buffer 422, the data Z cannot be written. Therefore, the data Y is compared with the data V by the data Z
May be difficult to transfer to the transmission buffer 422 as compared with the data V and Y, and the data may be delayed in the data relay device 4. On the other hand, the data controller 4 of the present embodiment
In 4A, the order of confirming the presence / absence of data is sequentially shifted every time one search is performed.
To 423. Also, since the confirmation order is not fixed, the time required for data
31 can be averaged.

In this data transfer process, the initial value of the start buffer # at the time of starting the data relay device 4A is 1
To N.

(Third Embodiment) FIG. 15 shows a data relay device and a multiplex communication system according to a third embodiment of the present invention. The following description focuses on the differences from the first embodiment.

The data relay device 4B is provided with a transmission data list 46. The transmission data list 46 can be schematically represented as shown in FIG. The information for specifying the buffer 431 storing the data to be transmitted to each of the multiplex communication lines 21 to 23 includes the MID and the number of stages.
Each of 1 to 23 includes a transfer destination management flag indicating whether or not the data should be transmitted. Like the transfer destination flag of the first embodiment, “1” indicates that the transfer is to be performed, and “0” indicates that transfer is unnecessary. The order indicates the order in which the data is written in the transmission data list 46.

From the transmission data list 46, paying attention to one of the multiplex communication lines 21 to 23, if the transfer destination management flag is “1”, the data to be transferred is transferred from the reception buffers 411 to 413 to the buffer 431. It is known that the data has been transferred, and if there are a plurality of such transfer destination management flags of "1", the transfer order is known. That is, the transfer is performed from the one with the highest rank. In the example shown in the figure, the transmission order of the first multiplex communication line 21 is MID = C8h for the first place, and the buffer 43 of two stages
The second rank indicates that the buffer 431 has MID = 92h and one stage. The first order of the transmission order of the third multiplex communication line 23 indicates that the buffer 431 has MID = 5Fh and two stages. The storage area of the transmission data list 46 is the RA that constitutes the data relay device 4B.
M.

The data controller 44B transmits data from the reception buffers 411 to 413 to the buffer group 43 at the time of data transfer processing and transmits data from the buffer group 43 to the transmission buffers 421 to 413.
There is provided data transfer management means 442B activated at the time of data transfer processing to 423, and buffer information (MID and stage number) of buffer 431 for storing received data.
The transmission data list 46 is updated by, for example, adding a transfer destination management flag to the transmission data list 46.

The data transfer process executed by the data controller 44B is shown in FIGS. 17, 18, 19, 20, and 2.
This will be described with reference to FIG. 17 to 19 show data transfer processing from the reception buffers 411 to 413 to the buffer group 43, and FIGS. 20 to 22 show data transfer processing from the buffer group 43 to the transmission buffers 421 to 423.

The process of transferring data to the buffer group 43 is a process of transferring data received from the first multiplex communication line 21 in steps S300 to S305 (FIG. 17).
Steps 306 to S311 (FIG. 18) are processing for transferring the data received from the second multiplex communication line 22.
S317 (FIG. 19) is the transfer processing of the data received from the third multiplex communication line 23. Steps S300 to S300
Steps 302, S 306 to S 308, and S 312 to S 314 are procedures as the buffer specifying means 441,
301 to S304, steps S307 to S310, and steps S313 to S316 are data transfer management means 442B.
The procedure is as follows.

In step S300, it is checked whether or not the reception buffer 411 for the first multiplex communication line is empty. If not, in step S301, the MID of the reception data stored in the reception buffer 411 is checked. Confirms the number of stages of the buffer 431 for storing the received data.
In this case, if the MID is one in which a plurality of buffers are allocated, a storage destination that does not store data is selected. Free buffer 43 in which no data is stored
The selection method when there are a plurality of 1s is arbitrary. If the data has been stored in all the buffers 431 assigned to the MID, the buffer 431 at the end of the transmission data list 46 with the same MID is selected as the storage destination of the received data. Next, step S3
At 03, the transfer destination of the received data is acquired based on the data transfer destination table 45.

In step S304, the buffer information and the initial value of the transfer destination management flag acquired in steps S301 to S303 are added to the end of the transmission data list 46. Here, the transfer destination management flag is set to “1” for the multiplex communication lines 21 to 23 to be transferred. In the case of overwriting, for example, when the buffer 431 at the end of the transmission data list 46 is selected as the storage destination of the reception data in step S302, only the transfer destination management flag of the transmission data list 46 is set in step S303. Reset based on the obtained transfer destination.

In the following step S305, the data in the reception buffer 411 for the first multiplex communication line is transferred to the predetermined buffer 431 of the buffer group 43 confirmed in steps S301 and S302. Then, the transfer processing of the data received from the second multiplex communication line 22 (steps S306 to S31)
Go to 1). In step S300, the first
If the reception buffer 411 for the multiplex communication line is empty, steps S301 to S305 are skipped, and the data received from the second multiplex communication line 22 is transferred (step S3).
06 to S311).

In step S306, it is checked whether or not the reception buffer 412 for the second multiplex communication line is empty. If it is not empty, step S306 is executed in the same manner as in steps 301 to 305.
In step 307, the MID of the reception data stored in the reception buffer 412 is checked, and in step S308, the number of stages of the buffer 431 for storing the reception data is checked. Next, in step S309, the transfer destination of the received data is acquired based on the data transfer destination table 45.

Next, at step S310, step S310
The transmission data list 46 is updated with the buffer information and the transfer destination management flag acquired in 307 to S309, and in step S311, the reception buffer 4 for the second multiplex communication line is updated.
12 data in the buffer group 43 in step S30.
7. Transfer to the predetermined buffer 431 confirmed in S308. Then, the processing shifts to the transfer processing of the data received from the third multiplex communication line 23 (steps S312 to S318). If the reception buffer 412 for the second multiplex communication line is empty in step S306, steps S307 to S3
11 is skipped, and the process proceeds to a process of transferring data received from the third multiplex communication line 23 (steps S312 to S3).
317).

In step S312, it is checked whether or not the reception buffer 413 for the third multiplex communication line is empty.
In step 313, the MID of the reception data stored in the reception buffer 413 is checked, and in step S314, the number of stages of the buffer 431 for storing the reception data is checked. Next, in step S315, the transfer destination of the received data is acquired based on the data transfer destination table 45.

Next, at step S316, at step S316
The transmission data list 46 is updated with the buffer information and the transfer destination management flag acquired in 313 to S315, and in step S317, the reception buffer 4 for the third multiplex communication line is updated.
13 in the buffer group 43 in step S31.
4. The data is transferred to the predetermined buffer 431 confirmed in S315, and the data transfer process is completed. Step S3
If the reception buffer 413 for the third multiplex communication line is empty in step 12, steps S313 to S317 are skipped, and the data transfer process ends.

Next, from the buffer 431 to each transmission buffer 4
The process of transferring data to 21 to 423 will be described. Steps S400 to S407 (FIG. 20) are performed by the buffer 431.
This is a process of transferring data from the transmission buffer 421 to the first multiplex communication line transmission buffer 421, and includes steps S408 to S415 (FIG. 2).
1) is a process of transferring data to the second multiplex communication line transmission buffer 422, and is performed in steps S416 to S423 (FIG. 2).
2) is a process for transferring data to the third multiplex communication line transmission buffer 423. Steps S400 to S406, steps S408 to S414, steps S416 to S422
Is a procedure as the data transfer management means 422B.

In step S400, it is checked whether the transmission buffer 421 for the first multiplex communication line is empty. If the transmission buffer 421 is empty, the flow advances to step S401 to set the transfer destination management flag for the first multiplex communication line in the transmission data list 46. Check whether all are “0”. If a negative determination is made, that is, the buffer 431
If there is data to be transferred from the first multiplex communication line to the transmission buffer 421 for the first multiplex communication line, the process proceeds to step S402, and the buffer information (MID) of the highest order among those whose first multiplex communication line transfer management flag is "1" And the number of steps). In a succeeding step S403, the data of the buffer 431 corresponding to the acquired buffer information in the buffer group 43 is stored in the first buffer.
The data is transferred to the transmission buffer 421 for the multiplex communication line. Then, in the transmission data list 46, the highest one of the transfer destination management flags for the first multiplex communication line that takes "1" is cleared ("0").

In the subsequent step S405, the other transfer destination management flags of the data for which the transfer destination management flag has been cleared, that is, the transfer destination management flags for the second and third multiplex communication lines are checked, and all the transfer destination management flags are checked. If the flag is "0",
In step S406, information on the data that has been transmitted to the transmission buffer 421 (buffer information and transfer destination management flag) is deleted from the transmission data list 46, and the following low-order information is moved up. Then, in step S407, the data that has been transmitted to the transmission buffer 421 is deleted from the buffer 431. Then, the process proceeds to step S408. If step S405 is affirmatively determined, steps S406 and S407 are skipped and step S4 is performed.
Proceed to 08.

As soon as the transmission buffer 421 becomes empty, data is transferred from the buffer 431 to the transmission buffer 421 in the order written in the transmission data list 46 in this manner, and the transmission buffer 421 waits for transmission to the first multiplex communication line 21. . If data has already been written to the transmission buffer 421 in step S400, or if a positive determination is made in step S401, that is, if there is no data to be transferred to the first multiplex communication line 21, step S408 (FIG. 21) Proceed to).

In steps S408 to S415, the transmission buffer 422 for the second multiplex communication line, the buffer 431 holding the data to be transferred thereto, the transmission data list 4
6, the same procedure as in steps S400 to S407 is performed. That is, if the transmission buffer 422 for the second multiplex communication line is empty (step S408) and the transfer destination management flag for the second multiplex communication line in the transmission data list 46 is "1" (step S409), the second The buffer information of the highest order among the ones for which the transfer destination management flag for two multiplex communication lines is “1” is obtained (step S410), and the data of the buffer 431 corresponding to the obtained buffer information is transferred to the transmission buffer 422 (step S410). S411). Then, the uppermost one of the transfer destination management flags for the second multiplex communication line in the transmission data list 46 is cleared (step S412).

Next, in step S413, another transfer destination management flag for the transferred data, that is, a transfer destination management flag for the first and third multiplex communication lines is confirmed.
If all the transfer destination management flags are "0", in step S414, the information of the data that has been transmitted to the transmission buffer 422 is deleted from the transmission data list 46, and the information of the lower rank is moved up. In step S415, The data that has been transmitted to the transmission buffer 422 is stored in the buffer 431.
Remove from. Then, the process proceeds to step S416 (FIG. 22).

In steps S416 to S423, the transmission buffer 423 for the third multiplex communication line, the buffer 431 holding the data to be transferred thereto, and the transmission data list 4
6, the same procedure as in steps S400 to S407 is performed. That is, if the transmission buffer 423 for the third multiplex communication line is empty (step S416) and the transfer destination management flag for the third multiplex communication line in the transmission data list 46 is “1” (step S417), The buffer information of the highest order among the ones for which the transfer destination management flag for three multiplex communication lines is "1" is obtained (step S418), and the data of the buffer 431 corresponding to the obtained buffer information is transferred to the transmission buffer 423 (step S418). S419). Then, the uppermost one of the third multiplex communication line transfer destination management flags in the transmission data list 46 is cleared (step S420).

Next, in step S421, another transfer destination management flag for the transferred data, that is, a transfer destination management flag for the first and second multiplex communication lines is confirmed.
If all the transfer destination management flags are “0”, in step S422, the information of the data that has been transmitted to the transmission buffer 423 is deleted from the transmission data list 46, and the information of the lower rank is moved up, and in step S423, The data that has been transmitted to the transmission buffer 423 is stored in the buffer 431.
Remove from. Thus, data transfer from the buffer 431 to the transmission buffers 421 to 423 is completed.

The data transfer process of the data controller 44B is set as described above.
In No. 6, information on data to be transmitted to the multiplex communication lines 21 to 23 is updated. The upper data in the transmission data list 46 is the data received earlier. Therefore, in each of the multiplex communication lines 21 to 23, the transmission buffers 421 to 423 wait for transmission in the order in which the data to be relayed is received. All buffers 431
Without checking the presence or absence of data for
Since the buffer in which the data to be transmitted written in 1 is stored is known from the transmission data list 46, the data can be relayed quickly.

(Fourth Embodiment) FIG. 23 shows a data relay device and a multiplex communication system according to a fourth embodiment of the present invention. The description will focus on the differences from the third embodiment.

The data relay device 4C is connected to each multiplex communication line 21
Transmission data lists 461, 462, 463 for each of ~ 23
Is provided. In the transmission data lists 461 to 463, information (MID and the number of stages) of a buffer storing data to be transmitted to each of the multiplex communication lines 21 to 23 is written in the transmission order, and is schematically illustrated in FIGS. (B), FIG.
4 (C). This is different from the transmission data list of the third embodiment in that a transfer destination management flag is not included.
In the example of the figure, the first order of transmission to the first multiplex communication line 21 is the data stored in the buffer 431 having MID = C8h and two stages, and the second order is the buffer 431 having MID = 92h and one stage. Indicates data. The storage area of the transmission data lists 461 to 463 is the data relay device 4
It is set on the RAM constituting C.

The data controller 44C is provided with a data transfer management means 442C which is activated when data is transferred from the reception buffers 411 to 413 to the buffer group 43.

The data transfer process executed by the data controller 4C is shown in FIGS. 25, 26, 27, 28, and 2.
This will be described with reference to FIG. FIGS. 25 to 27 show data transfer processing from the reception buffers 411 to 413 to the buffer group 43, and FIGS. 28 to 30 show data transfer processing from the buffer group 43 to the transmission buffers 421 to 423.

The process of transferring data to the buffer group 43 is a process of transferring data received from the first multiplex communication line 21 in steps S500 to S508 (FIG. 25).
509 to S517 (FIG. 26) are the transfer processing of the data received from the second multiplex communication line 22, and are performed in steps S518 to S517.
S526 (FIG. 27) is the transfer processing of the data received from the third multiplex communication line 23. Steps S500 to S500
Steps 502, S509 to S511, and S518 to S520 are procedures as the buffer designating means 441.
501 to S507, steps S510 to S516, and steps S519 to S525 are data transfer management means 442C.
The procedure is as follows.

In step S500, it is checked whether or not the reception buffer 411 for the first multiplex communication line is empty. If not, in step S501, the MID of the reception data in the reception buffer 411 is checked. Confirm the number of stages of the buffer 431 for storing the data of the MID. Next, in step S503, the transfer destination of the received data is obtained based on the data transfer destination table 45.

In the following step S504, it is confirmed whether or not the acquired transfer destination has a transmission buffer 422 for the second multiplex communication line. If the result is affirmative, the flow advances to step S505. In step S505, at the end of the transmission data list 462 for the second multiplex communication line 22, steps S501 and S502 are added.
The buffer information (MID and the number of stages) confirmed in is added, and the process proceeds to step S506. In step S506, it is confirmed whether or not the acquired transfer destination has a transmission buffer 423 for the third multiplex communication line. If the result is affirmative, the process proceeds to step S507. In step S507, the buffer information (MI) confirmed in steps S501 and S502 is added to the end of the transmission data list 463 for the third multiplex communication line 23.
D and the number of stages) are added, and the process proceeds to step S508. If the same buffer information already exists in the transmission data lists 462 and 463 in steps S505 and S507, the buffer information is added and the buffer information already written in the transmission data lists 462 and 463 is deleted.

In step S508, the data in the reception buffer 411 for the first multiplex communication line is transferred to a predetermined buffer 431 of the buffer group 43 specified by the buffer information. Then, the process shifts to a transfer process of data received from the second multiplex communication line 22 (steps S509 to S517). When the reception buffer 411 for the first multiplex communication line is empty in step S500, the process of adding to the transmission data lists 462 and 463 for the second and third multiplex communication lines (steps S501 to S507) and the data transfer The process (step S508) is skipped, and the data received from the second multiplex communication line 22 is transferred (step S50).
9 to S517).

In step S509, it is checked whether the reception buffer 412 for the second multiplex communication line is empty. If not, the MID of the reception data in the reception buffer 412 is checked in step S510. Confirm the number of stages of the buffer 431 for storing the data of the MID. Next, in step S512, the transfer destination of the received data is acquired based on the data transfer destination table 45.

In the following step S513, it is confirmed whether or not the transmission buffer 421 for the first multiplex communication line is present at the obtained transfer destination. If the result is affirmative, the flow advances to step S514. In step S514, steps S510 and S511 are added to the end of the transmission data list 461 for the first multiplex communication line 21.
The buffer information (MID and the number of stages) confirmed in the above is added, and the process proceeds to step S515. In step S515, it is confirmed whether or not the acquired transfer destination has the transmission buffer 423 for the third multiplex communication line. If the result is affirmative, the process proceeds to step S516. In step S516, the buffer information (MI) confirmed in steps S510 and S511 is added to the end of the transmission data list 463 for the third multiplex communication line 23.
D and the number of stages) are added, and the flow advances to step S517. If the same buffer information already exists in the transmission data lists 461 and 463 in steps S514 and S516, the buffer information is added and the buffer information already written in the transmission data lists 461 and 463 is deleted.

In step S517, the data in the reception buffer 412 for the second multiplex communication line is transferred to the buffer 431 specified by the buffer information in the buffer group 43. Then, the processing shifts to the transfer processing of the data received from the third multiplex communication line 23 (steps S518 to S526). If the reception buffer 412 for the second multiplex communication line is empty in step S509, the process of appending to the transmission data lists 461 and 463 for the first and third multiplex communication lines (steps S510 to S516) and the data transfer The process (step S517) is skipped and the third multiplex communication line 23 is skipped.
Of the data received from the server (steps S518 to S518)
526).

In step S518, it is determined whether the reception buffer 413 for the third multiplex communication line is empty. If not, in step S519, the MID of the reception data stored in the reception buffer 413 is confirmed. Confirm the number of stages of the buffer 431 for storing the data of the MID. Next, in step S521, the transfer destination of the received data is acquired based on the data transfer destination table 45.

In the following step S522, it is checked whether or not the acquired transfer destination has a transmission buffer 421 for the first multiplex communication line. If the result is affirmative, the flow advances to step S523. In step S523, at the end of the transmission data list 461 for the first multiplex communication line 21, steps S519 and S520 are added.
The buffer information (the MID and the number of stages) confirmed in the above is added, and the process proceeds to step S524. In step S524, the transmission destination for the second multiplex communication line 4
It is confirmed whether or not there is 22. If affirmative, step S5
Go to 25. In step S525, the second multiplex communication line 2
Step S5 is added to the end of the transmission data list 462 for
19, the buffer information (MID and the number of stages) confirmed in S520 is added, and the flow advances to step S526. It should be noted that, in steps S523 and S525, the transmission data list 4
If the same buffer information already exists in 61 and 462,
The buffer information is added and the transmission data list 46 is added.
1, 462 is deleted.

In step S526, the data in the reception buffer 413 for the third multiplex communication line is transferred to a predetermined buffer 431 specified by the buffer information in the buffer group 43, and is transferred from the reception buffers 411 to 413 to the buffer 431.
The data transfer process to the server ends. Step S51
8, when the reception buffer 413 for the third multiplex communication line is empty, additional processing is performed on the transmission data lists 461 and 462 for the first and second multiplex communication lines (steps S519 to S5).
25) and the data transfer process (step S526) are skipped, and the data transfer process ends.

Next, from the buffer 431 to each transmission buffer 4
The process of transferring data to 21 to 423 will be described. Steps S600 to S606 (FIG. 28) correspond to the buffer 431.
This is a process of transferring data from the transmission buffer 421 to the first multiplex communication line transmission buffer 421, and includes steps S607 to S613 (FIG. 2).
9) is a process of transferring data to the second multiplex communication line transmission buffer 422, which is performed in steps S614 to S620 (FIG. 3).
0) is a process of transferring data to the third multiplex communication line transmission buffer 423. Steps S601 to S604, steps S608 to S611, steps S615 to S618
Is a procedure as the data transfer management means 442C.

In step S600, it is checked whether the transmission buffer 421 for the first multiplex communication line is empty. If it is empty, the flow advances to step S601 to determine whether the transmission data list 461 for the first multiplex communication line is empty. Check. If the transmission data list 461 is not empty, that is, if there is data to be transferred from the buffer 431 to the transmission buffer 421, step S
Proceeding to 602, the buffer information at the head of the transmission data list 461 is acquired. In step S603, the data of the buffer 431 specified by the acquired buffer information in the buffer group 43 is transferred to the transmission buffer 421 for the first multiplex communication line. Next, the transmission data list 46
The first buffer information, that is, the information of the data transferred in step S603 is deleted, and the lower-order information is moved up.

In the subsequent step S605, it is determined whether or not the transmission data lists 642, 643 for the second and third multiplex communication lines have the same buffer information deleted in the step S604. Then, the data is deleted from the buffer 431 storing the data whose transfer has been completed in step S603, and the process proceeds to step S605. The buffer 431 becomes available as soon as the transmission buffer 421 becomes empty in the order written in the transmission data list 461.
Is transferred to the transmission buffer 421, where the transmission buffer 421 waits for transmission to the first multiplex communication line 21. If data has already been written to the transmission buffer 421 in step S600, or if the transmission data list 461 is empty and there is no data to be transferred in step S601, steps S602 to S606 are skipped and step S607 (FIG. Proceed to 29).

In steps S607 to S613, the transmission buffer 422 for the second multiplex communication line, the buffer 431 holding the data to be transferred thereto, the transmission data list 4
For 62, the same procedure as in steps S600 to S606 is performed. That is, if the transmission buffer 422 for the second multiplex communication line is empty (step S607) and the transmission data list 462 for the second multiplex communication line is written (step S608), the buffer information at the head of the transmission data list 462 Is read (step S609), and data is transferred from the buffer 431 specified by the buffer information to the transmission buffer 422 (step S610). Then, the buffer information of the first data of the transmission data list 462, that is, the buffer of the transferred data is deleted, and the following low-order information is moved up (step S611).

Next, if the first and third multiplex communication line transmission data lists 641 and 643 do not include the same buffer information deleted in step S611 (step S61).
2), the data is deleted from the buffer 431 in which the data that has been transferred in step S610 is stored (step S610).
613), and proceeds to step S614 (FIG. 30).

In steps S614 to S620, the transmission buffer 423 for the third multiplex communication line, the buffer 431 holding the data to be transferred thereto, the transmission data list 4
For 63, the same procedure as in steps S600 to S606 is performed. That is, if the transmission buffer 423 for the third multiplex communication line is empty (step S614) and the transmission data list 463 for the third multiplex communication line is written (step S615), the buffer information at the head of the transmission data list 463 is read. Is read (step S616), and data is transferred from the buffer 431 specified by the buffer information to the transmission buffer 423 (step S617). Then, the buffer information of the head data of the transmission data list 463, that is, the buffer information of the transferred data is deleted, and the following low-order information is moved up (step S61).
8).

Next, if the first and second multiplex communication line transmission data lists 641 and 642 do not contain the same buffer information deleted in step S618 (step S61).
9), the data is deleted from the buffer 431 in which the data that has been transferred in step S617 is stored (step S617).
620), from the buffer 431 to the transmission buffers 421 to 4
Then, the transfer process to the server 23 ends.

The data transfer process of the data controller 44C is set as described above, and the transmission data lists 461 to 463 are updated with buffer information of data to be transmitted to the corresponding multiplex communication lines 21 to 23. The order in the transmission data lists 461 to 463 is the order of reception. For example, in the example of FIG. 24, in the transmission data list 461 for the first multiplex communication line, the data of C8h in the first place in the transmission order from the buffer group 431 is transferred to the transmission buffer 421, and the buffer information ( MI
Assuming that D = C8h and the number of stages 2 are deleted, the buffer information (MID = C8h and the number of stages 2) does not include the transmission data lists 462 and 463 for the second and third multiplex communication lines. From this, the buffer information (MID = C8
h, the number of data in the buffer 431 specified by the number of stages 2) is known to have completed all transfer.
1 will be deleted.

Incidentally, even with the same data of MID = C8h,
Even if the data of the buffer information (MID = C8h, the number of stages is 1) of the first transmission order in the transmission data list 462 for the second multiplex communication line is transmitted, the same buffer information is transmitted in the transmission data list for the first multiplex communication line. 461, buffer information (MID) from the transmission data list 462 for the second multiplex communication line.
= C8h, the number of stages 1) is deleted, the data stored in the buffer 431 is not deleted and is basically held until it is transmitted to the transmission buffer 421 for the first multiplex communication line.

Thus, as in the third embodiment, the buffer 431 storing the data to be transmitted written in the buffer 431 is stored in the transmission data list 461 without checking the presence / absence of data in all the buffers 431.
463, data can be relayed quickly. In addition, since the transmission order to each of the multiplex communication lines 21 to 23 is the order of reception, all the received data can be transmitted without delay.

Further, each transmission data list 461 to 463
Are arranged in the order in which the buffer information is transferred for each of the multiplex communication lines 21 to 23.
When a plurality of pieces of buffer information of the same MID are arranged corresponding to each of the above, the data is not deleted even after the transfer to a certain transmission buffer 421 to 423, but the data to be transferred next to the same transmission buffer 421 to 423 There is no mistake.

Further, for some MIDs, such as C8h in the example shown in FIG.
Since a plurality of data of the same MID received successively by the data relay device 4C can be entered in the transmission data lists 461 to 463 as data to be transmitted, resistance to data loss can be increased.

In each of the above embodiments, when data is received and the buffer is full, the data is overwritten. However, the data controller temporarily transfers the data to the buffer while holding the data in the reception buffer. May be set to be suspended. If the buffer becomes empty during that time, overwriting can be avoided. In this case, as shown in FIG. 31, a plurality of reception buffers 411 are provided for each multiplex communication line 21 to perform data processing in a FIFO type, avoiding overwriting in the buffer 431, and ensuring operation of receiving data from the multiplex communication line 21. Can be achieved.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a first data relay device and a multiplex communication system of the present invention.

FIG. 2 is a diagram showing a frame structure of communication data of a first data relay device and a multiplex communication system of the present invention.

FIG. 3 is a diagram showing the correspondence between the types of communication data and their MIDs in the first data relay device and the multiplex communication system of the present invention.

FIG. 4 is a schematic diagram of a buffer of the first data relay device of the present invention.

FIG. 5 is a diagram showing a correspondence relationship between data and its transfer destination in a transfer destination table of the first data relay device of the present invention.

FIG. 6 is a first flowchart showing control executed in a data controller of the first data relay device of the present invention.

FIG. 7 is a second flowchart showing control executed in the data controller of the first data relay device of the present invention.

FIG. 8 is a third flowchart showing control executed in the data controller of the first data relay device of the present invention.

FIG. 9 is a fourth flowchart showing the control executed in the data controller of the first data relay device of the present invention.

FIGS. 10A and 10B are diagrams showing the operation of the first data relay device of the present invention.

11A is a diagram illustrating settings of the data controller, and FIGS. 11B and 11C are diagrams illustrating settings of a modification, respectively.

FIG. 12 is a configuration diagram showing a modification of the data relay device and the multiplex communication system of the present invention.

FIG. 13 is a configuration diagram of a second data relay device and a multiplex communication system of the present invention.

FIG. 14 is a flowchart showing control executed in the data controller of the second data relay device of the present invention.

FIG. 15 is a configuration diagram of a third data relay device and a multiplex communication system of the present invention.

FIG. 16 is a diagram showing a configuration of a transmission data list of the third data relay device of the present invention.

FIG. 17 is a first flowchart showing the control executed in the data controller of the third data relay device of the present invention.

FIG. 18 is a second flowchart showing the control executed in the data controller of the third data relay device of the present invention.

FIG. 19 is a third flowchart showing the control executed in the data controller of the third data relay device of the present invention.

FIG. 20 is a fourth flowchart illustrating control executed in the data controller of the third data relay device of the present invention.

FIG. 21 is a fifth flowchart showing the control executed in the data controller of the third data relay device of the present invention.

FIG. 22 is a sixth flowchart showing control executed in the data controller of the third data relay device of the present invention.

FIG. 23 is a configuration diagram of a fourth data relay device and a multiplex communication system of the present invention.

FIGS. 24 (A), (B) and (C) are diagrams each showing a configuration of a transmission data list of the fourth data relay device of the present invention.

FIG. 25 is a first flowchart showing control executed in the data controller of the fourth data relay device of the present invention.

FIG. 26 is a second flowchart showing the control executed in the data controller of the fourth data relay device of the present invention.

FIG. 27 is a third flowchart showing control executed in the data controller of the fourth data relay device of the present invention.

FIG. 28 is a fourth flowchart showing the control executed in the data controller of the fourth data relay device of the present invention.

FIG. 29 is a fifth flowchart showing the control executed in the data controller of the fourth data relay device of the present invention.

FIG. 30 is a sixth flowchart showing the control executed in the data controller of the fourth data relay device of the present invention.

FIG. 31 is a configuration diagram showing another modified example of the data relay device and the multiplex communication system of the present invention.

FIG. 32 is a configuration diagram of a typical example of a conventional data relay device and a multiplex communication system.

FIG. 33 is a schematic diagram of a main body of communication data.

[Explanation of symbols]

11, 12, 13 Communication system 21, 22, 23 Multiplexed communication line 31, 32, 33 Communication node 4, 4A, 4B, 4C Data relay device 411, 412, 413 Receive buffer 421, 422, 423 Transmission buffer 43 Buffer group 431 Buffers 44, 44A, 44B, 44C Data controller 441 Buffer designating means 442, 442A, 442B, 442C Data transfer management means 45 Transfer destination table 46, 461, 462, 463 Transmission data list

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Kenji Tomita 14th Iwatani Shimowasakucho, Nishio City, Aichi Prefecture Inside the Japan Auto Parts Research Institute (72) Inventor Ikuo Hayashi 14th Iwatani Shimowasumicho Nishio City, Aichi Prefecture Stock Company (72) Inventor Tomohisa Kishigami 1-1-1 Showa-cho, Kariya-shi, Aichi Prefecture Inside DENSO Corporation (72) Inventor Hiroshi Honda 1-Toyota-cho, Toyota-shi, Aichi Prefecture Inside Toyota Motor Corporation F term (reference) 5K033 AA05 BA06 CB01 CB17 DB13 DB18 EA06 EA07 5K034 AA05 CC06 CC07 HH01 HH02 HH04 HH17 HH23 HH37 HH43 MM21 MM24

Claims (6)

[Claims] 1. A data relay device interposed between a multiplex communication line for transmitting data including data type information together with a data main body and relaying a plurality of types of data, wherein the data relay device relays received data. In a data relay device having a data controller for selecting a previous multiplex communication line and transferring received data, a buffer for temporarily holding received data before transmitting the received data to the relay multiplex communication line is provided for each type of data to be relayed. A plurality of buffers are allocated for one or more data types among the data types. The data controller identifies the type of the received data, and sets the buffer corresponding to the type as a write destination of the received data. Buffer designating means for designating, and data transfer managing means for managing data transfer from a buffer in which data is stored Wherein the data transfer management means is set so that, in each multiplex communication line, the order of transferring data from a buffer of the same data type is the order in which data is written to the buffer. Data relay device. 2. The data relay device according to claim 1, wherein said data transfer management means is activated at predetermined time intervals, and sequentially checks the presence or absence of data to be transmitted in said buffer. A data relay device which is set so as to transfer data and to check the presence / absence of data in a buffer having the same data type from a buffer in which data is stored first. 3. The data relay device according to claim 2, wherein said data transfer management means checks whether or not there is data in the buffer only for a predetermined buffer set for a buffer of the same data type. And, after the transfer of the data in the predetermined buffer is completely completed in correspondence with the selected multiplex communication line, the data received first among the data in the other buffers having the same data type Is set to move to the predetermined buffer. 4. The data relay device according to claim 1, further comprising buffer information for specifying a buffer in which data is stored, wherein the selected multiplex communication line has the same buffer information transfer order from the buffer. A data relay device comprising a transmission data list in an order, wherein the data transfer management means is set to update the transmission data list in accordance with writing of data to a buffer and transfer of data from the buffer. 5. The data relay device according to claim 4, wherein the transmission data list is provided with an initial value for each multiplex communication line based on buffer information for specifying a buffer and the transfer destination table. And a management information indicating whether or not the data stored in the buffer should be transferred. The data transfer management means is configured to transmit the management information according to the transfer of the data from the buffer to the effect that the data transmission is unnecessary. Data relay device set to switch to. 6. A multiplex communication system, comprising: the data relay device according to claim 1; and a plurality of communication systems in which communication nodes for transmitting and receiving data are connected to the multiplex communication line. .