JP3471515B2 - Cyclic communication control method and cyclic communication device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cyclic communication control method for updating data in a network shared memory space of a plurality of stations connected to each other via a network, and a cyclic communication control method using the cyclic communication control method. The present invention relates to a communication device.

[0002]

2. Description of the Related Art FIG. 17 shows, for example, Mitsubishi Electric Technical Report, Vol.
65, No. FIG. 1 is a block diagram schematically showing a conventional cyclic communication control method and cyclic communication device disclosed in 7, 1991, in which 1, 2, 3 are various control devices such as a computer for controlling a plant. A certain station, 4 is FDDI which is a ring type optical LAN
(Fiber Distributed Data I
interface), 11, 12, and 13 are cyclic memories of the stations 1, 2, and 3, respectively.

In recent years, against the background of efficient plant operation, system hierarchy for plant control and the like, integration of subsystems such as control, instrumentation, information, etc. have been carried out. Has introduced many new features. One of its functions is a cyclic communication control method and a cyclic communication device as shown in FIG.

Next, the operation will be described. The data way of the cyclic communication control method shown in FIG. 17 has a unique protocol for cyclic transfer and data block transfer, a MAC bridge function of IEEE802.3 LAN, and a communication function for network management / fault management.
Built on DDI4.

Each of the stations 1, 2, and 3 has a network shared memory space called a cyclic memory 11, 12, and 13, and a specific area in this network shared memory space is assigned to its own transmission area. At the stations 1, 2 and 3, the data in the transmission areas of the cyclic memories 11, 12 and 13 are based on predetermined cyclic communication information (address of cyclic data, data length, etc.) at the time of cyclic transmission. Is read and broadcast (broadcast) via the FDDI 4 together with the memory address information, and the other stations receiving the same develop the received data in the same area in their cyclic memory. As described above, in cyclic transfer, communication between stations 1, 2, and 3 is possible only by writing / reading the cyclic memories 11, 12, and 13 without performing a complicated procedure.

[0006] Such a cyclic memory 11, 1
In order to maintain the update cycles of 2 and 13 at high speed, the frame for cyclic data transfer is fixedly assigned to the synchronous transmission of the FDDI 4, and the data in the transmission area is framed and transmitted every time a token is acquired. Furthermore, if the delay time from the transfer of the cyclic transfer data to be transmitted to the transmission buffer memory to the actual transmission is large, it may cause a deterioration in the update speed of the cyclic memories 11, 12, and 13, In order to eliminate it, a high-speed DMA controller (a direct memory access control device that does not use a microprocessor) is used to perform transmission of a frame on the transmission buffer memory and update of transmission data in parallel. The cyclic transfer can be simultaneously transmitted in high-speed and low-speed cycles, and any area in the cyclic memories 11, 12 and 13 can be set to any of them. This cyclic data transfer function is used for data transfer that requires high-speed processing in a plant, for example, transfer of control process input / output data.

[0007]

Since the conventional cyclic communication control method and cyclic communication device are configured as described above, cyclic data can be obtained by hardware based on preset cyclic communication information. It is used to send from each station every time a token is acquired, but it is possible to stop the cyclic data transmission sequence while the system is operating, or to control some cyclic data to be transmitted at the time of testing. In order to perform control such as switching from the transmission of all cyclic data to the transmission of the type of cyclic data in order to switch the duplex station while the system is operating, the hardware DMA is forced. It is necessary to perform processing such as stopping the communication or rewriting the cyclic communication information. Treatment there is a problem that a lot of time according to control of the complex and therefore more such cyclic data transmission sequence.

The FD used in the conventional cyclic communication control method and cyclic communication device
Due to the characteristics of DI4, it is not possible to perform cyclic transmission unless a token is acquired, and in the conventional cyclic communication control method and cyclic communication device, packet exchange is adopted and the packet addressed to itself is discarded. There was a problem that a single loopback test could not be executed at each station.

Furthermore, in the conventional cyclic communication control method and cyclic communication device, since the variable length packet is always the unit of transmission and reception and the data length thereof is not constant, the cyclic data transmission sequence control as described above and In order to process the received cyclic data and to process data such as adding CRC information, the processing on the hardware becomes complicated and the scale of the hardware becomes large.

The present invention has been made in order to solve the above problems, and is an ATM (transmission / switching method) in an integrated network which has been used in recent years and which can meet a wide variety of communication service requests. Asynchron
ous Transfer Mode) is adopted to stop the cyclic data transmission sequence during system operation, control to transmit some cyclic data during testing, etc. An object of the present invention is to provide a cyclic communication control method and a cyclic communication device capable of executing high-speed control such as switching from transmission of all cyclic data to transmission of a type unit of cyclic data for switching.

Further, the present invention provides a cyclic communication control method capable of easily confirming the soundness of cyclic transmission operation by executing a single loopback test and processing the received cyclic data. With the goal.

A further object of the present invention is to provide a cyclic communication control method capable of ensuring the quality by processing the cyclic data to be transmitted to check the validity of the cyclic data.

[0013]

Means for Solving the Problems] Cyclic communication control method according to the first aspect of the present invention, when performing a cyclic transmission sequence, the cyclic transmission control data
The contents of the transmission enable register are compared to determine whether or not cyclic data should be transmitted for each cyclic data, and if the cyclic data is to be transmitted, the cyclic data is received when another station receives it. AT by adding the control information necessary for writing the click data to its own cyclic memory for each cyclic data
This is to create M cells.

In the cyclic communication control method according to the invention of claim 2, an ATM cell is created and transmitted when a predetermined transmission period preset for transmitting the ATM cell as the CBR elapses.

In the cyclic communication control method according to the third aspect of the invention, the cyclic transmission control data is composed of at least one bit, and it is determined whether transmission is possible or not according to the contents of the cyclic transmission control data. A transmission enable register is provided for comparing the cyclic transmission control data with the contents of the transmission enable register to determine whether or not cyclic data should be transmitted for each cyclic data.

A cyclic communication control method according to a fourth aspect of the present invention is a cyclic communication control method in which a predetermined logical operation is performed on cyclic transmission control data and the contents of a transmission enable register to determine the operation result. It is determined whether or not cyclic data should be transmitted for each data.

In the cyclic communication control method according to a fifth aspect of the invention, the cyclic transmission control data is classified into a plurality of groups according to the type of cyclic data.

According to a sixth aspect of the cyclic communication control method of the present invention, a predetermined value of the cyclic transmission control data means stop of the cyclic transmission sequence, and the cyclic transmission control data is executed when the cyclic transmission sequence is executed. Is a predetermined value, the cyclic transmission sequence is stopped.

A cyclic communication control method according to a seventh aspect of the present invention is a cyclic communication control method in which an area for storing control information necessary for reflecting cyclic data received by another station in its own cyclic memory is cyclic. It is provided on the memory.

In the cyclic communication control method according to the invention described in claim 8, in the single loopback test, the cyclic data transmitted by the station itself is received, and all the bit values of the received cyclic data are inverted. It writes to cyclic memory.

According to a ninth aspect of the cyclic communication control method of the present invention, during the single loopback test, the cyclic data transmitted by the station itself is received, and the value of the received cyclic data is shifted by one bit to perform the cyclic data control. It is written in the click memory.

According to a tenth aspect of the cyclic communication control method of the present invention, in the single loopback test, the cyclic data transmitted by the station itself is received, and the address at which the received cyclic data is stored is shifted by a predetermined value. It writes it to cyclic memory.

According to the eleventh aspect of the cyclic communication control method of the present invention, the values of all the bits of the cyclic data received from the host of the station are inverted according to the contents of the test setting register that can be set, or The value is written in the cyclic memory by shifting the value by 1 bit or shifting the address to be stored by a predetermined value.

According to the twelfth aspect of the cyclic communication control method of the present invention, the cyclic transmission sequence is forcibly stopped in response to a request from the host of the station.

According to the thirteenth aspect of the cyclic communication control method of the present invention, the cyclic transmission sequence is forcibly stopped in response to an emergency stop signal input from the outside of the station.

In the cyclic communication control method according to the invention of claim 14, CRC information is added to the cyclic data when transmitting the cyclic data, and the validity of the cyclic data is verified based on the CRC information when receiving the cyclic data. It verifies and discards the cyclic data if the received cyclic data is not valid.

The cyclic communication device according to the invention of claim 15 is the cyclic transmission control data when the cyclic data stored in the cyclic memory is transmitted to another cyclic communication device through the ATM switch. And the contents of the transmission enable register are compared to determine whether or not cyclic data should be transmitted for each cyclic data, and if the cyclic data is to be transmitted, other And an ATM cell creating means for creating an ATM cell by adding control information necessary for writing cyclic data received by the cyclic communication device of the present invention to its cyclic memory. Is.

[0028]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below. Embodiment 1. 1 is a block diagram showing a configuration of a station which is an example of a cyclic communication control method and a cyclic communication device using this cyclic communication control method according to Embodiment 1 of the present invention.
Reference numeral 101 is an ATM exchange, which is the A of the received ATM cell.
ATM to send an ATM cell to a designated station in the network based on the contents of the TM cell header
Performs cell switching. Further, 102 is a station for transmitting and receiving cyclic data, 103 is a station for connecting the station 102 to the ATM switch 101, and at the time of transmission, an ATM cell transfer request from the ATM layer is received.
Conversion of cells into information on the physical medium for the actual transmission, conversion from the ATM layer to the physical layer for transmission,
A line control unit that performs the reverse conversion from the physical layer to the ATM layer at the time of reception, a reception ATM cell conversion unit 104 that recognizes the received ATM cell and converts the ATM cell into the cyclic data ATM cell, Reference numeral 105 denotes a cyclic memory which is a network shared memory space. Further, 106 is a host, and 107 is a CBR (Con
In order to transmit cyclic data as a stan bit rate), a timer for notifying the cyclic data transmission format conversion control unit shown below of the passage of a predetermined transmission cycle at the time of transmission, 108 controls transmission of cyclic data Transmit enable register for
Reference numeral 109 denotes cyclic data for transmission which is read from the cyclic memory 105 in response to the notification indicating the elapse of the transmission cycle from the timer 107, and cyclic communication information ( Control information) 201, and cyclic data transmission format conversion control unit for transmitting cyclic data ATM cells to the transmission ATM cell conversion unit 111 shown below, and 110 is cyclic communication information provided for each cyclic data. A transmission information storage memory for storing
Reference numeral 1 is a transmission ATM cell conversion unit for adding an ATM cell header to a cyclic data ATM cell and transmitting the ATM cell, and 112 is a cyclic memory 10 for extracting cyclic data from the received cyclic data ATM cell.
5 is a reception cyclic data storage control unit for storing in FIG. The cyclic data transmission format conversion control unit 109 is a cyclic data transmission determination unit and an AT.
The transmission ATM cell conversion unit 111 corresponds to a part of the ATM cell creation unit, the transmission information storage memory 110 corresponds to the transmission information storage unit, and the reception A
The TM cell conversion unit 104 and the reception cyclic data storage control unit 112 correspond to ATM cell reception means.

As is well known, the ATM adopted in the present invention performs transmission / reception in units of 53-byte fixed length ATM cells, and does not allocate a band in a time-division manner like circuit switching, but rather as a communication channel. It has the feature that the necessary band can be freely allocated. Therefore,
High-speed small-volume data communication between computers, image data communication that sends large amounts of data instantaneously, voice communication, and communication that wants to secure a fixed cycle band such as cyclic communication of the present invention all coexist. An environment in which communication is possible is provided. Further, in ATM, the length of an ATM cell to be transmitted is not variable like packet switching, but is a small fixed length of 53 bytes, and processing in lower layers such as an ATM layer and a physical layer is simple, so that software can be used. The processing in the lower layer can be realized by hardware without intervening the processing, and the control of the cyclic transmission sequence described below and the data processing and the transmission control at the time of the single loopback test described in the third embodiment and below can be easily performed. And there is a merit that it can be done easily.

Next, the operation will be described. First, the configurations and functions of the transmission information storage memory 110 and the cyclic memory 105 will be described in detail. 2A and 2B are diagrams showing an example of cyclic communication information stored in the transmission information storage memory 110 and cyclic data stored in the cyclic memory 105, respectively. As shown in FIG. 2A, the transmission information storage memory 110 stores one or a plurality of cyclic communication information 201. Each cyclic communication information 201 includes the next information data address 202, VC (V
virtual channel) index203,
It is composed of cyclic transmission control data 204, cyclic data address 205, and cyclic data length 206. The next information data address 202 indicates the address of the cyclic communication information 201 to be processed next by the cyclic data transmission format conversion control unit 109, and the VC index 203 is used when the ATM switch 101 switches ATM cells. The cyclic transmission control data 204 is information for the cyclic data transmission format conversion control unit 109 to compare this with the content (value) of the transmission enable register 108 to control the transmission. The address 205 indicates the address of the cyclic data 207 in the cyclic memory 105 designated by the cyclic communication information 201, and the cyclic data length 206
Indicates the size of effective data included in the cyclic data 207.

When the system including the station 102 is started, the host 106 is activated by the cyclic memory 105.
The calculation of the transmission cycle of at least one cyclic data 207 that will be stored in
As shown in (a), at least one cyclic communication information 201 corresponding to the cyclic data 207 is stored in the transmission information storage memory 110, the calculated predetermined transmission cycle is set in the timer 107, and at least 1
Cyclic memory 1 for one cyclic data 207
It stores in 05. When the transmission cycle elapses, the timer 107 causes the cyclic data transmission format conversion control unit 1
09 is notified that the transmission cycle has elapsed. Cyclic data transmission format conversion control unit 10 that received the notification
9 indicates the cyclic data 2 by comparing the cyclic transmission control data 204 included in the cyclic communication information 201 stored in the transmission information storage memory 110 with the value written in the transmission enable register 108.
07 is determined to be transmittable / impossible. When the transmission is possible, the cyclic data address 205 is referred to, the corresponding cyclic data 207 is extracted from the cyclic memory 105, and the cyclic communication information 201 is added to this. Then, the data is converted into cyclic data ATM cells and transmitted to the transmission ATM cell conversion unit 111. Generally, in the cyclic transmission sequence, the cyclic data is transmitted in a predetermined transmission cycle, that is, CBR, but the cyclic communication control method and the cyclic communication device according to the first embodiment also have such a configuration. VBR (Variable) by adopting various transmission methods.
It can be made simpler than that using Bit Rate).

The transmission ATM cell conversion unit 111 overwrites the received cyclic data ATM cell with an ATM cell header to form an ATM cell, and transmits the ATM cell to the line control unit 103. The line control unit 103 receives an ATM cell transfer request from the transmission ATM cell conversion unit 111, that is, an ATM cell transfer request from the ATM layer, converts the ATM cell into information on a physical medium that actually transmits, and converts the ATM layer into a physical layer. The converted ATM cell is transmitted to the ATM switch 101. The ATM switch 101 generally has its AT
Virtual channel identifier (VCI: Virt) which is a logical connection described in the ATM cell header of the M cell.
ual Channel Identifier (hereinafter abbreviated as VCI) and virtual path identifier (VPI: Virtu)
al Path Identifier (hereinafter abbreviated as VPI), and ATM cells are switched to another station 102 designated in advance in the network by this logical connection. In the first embodiment, ATM cells are switched by using only VCI.

The other station 102 which has received the ATM cell converts the physical layer into the ATM layer by the line control unit 103 and sends the received ATM cell to the reception ATM cell conversion unit 104. The reception ATM cell conversion unit 104 recognizes the received ATM cell, removes the ATM cell header from the ATM cell, converts it into a cyclic data ATM cell, and receives the reception cyclic data storage control unit 11
Notify 2. Reception cyclic data storage control unit 11
2 is the cyclic communication information 201 added from the cyclic data ATM cell at the transmitting station 102.
To remove the cyclic data 207 and extract the cyclic communication information 201 from the transmitting station 10.
The address at which the cyclic data 207 added in 2 should be stored, that is, the cyclic data address 205 is checked and stored in its own cyclic memory 105.

Next, the operation of the cyclic data transmission format conversion control unit 109 will be described with reference to FIGS. 3 and 4. FIG. 3 shows the transmission enable register 10
8 is an explanatory diagram showing an example of transmission control according to a combination of the contents of No. 8 and the contents of cyclic transmission control data 204 included in the cyclic communication information 201 added to the cyclic data 207 to be transmitted, and FIG. FIG. 4 is an explanatory diagram showing a process in which cyclic communication information 201 is added to cyclic data 207 and a cyclic data ATM cell 401 is created. The cyclic data transmission format conversion control unit 109 compares the cyclic transmission control data 204 set for each cyclic communication information 201 with the value of the transmission enable register 108 set by the host 106 to obtain the cyclic data. It is determined whether or not 207 can be transmitted.

In the example shown in FIG. 3, the cyclic transmission control data 204 and the transmission enable register 108 are both 4 bits, and the cyclic data transmission format conversion control unit 109 has the transmission enable register 108.
A of the contents of the message and the cyclic transmission control data 204
ND is taken and the cyclic transmission control data 204 is "1".
In the case other than "111" and the value obtained by logically ANDing is not "0000", it is determined that transmission is possible, and the cyclic data 207 is stored in the cyclic memory 105 based on the cyclic data address 205 in the cyclic communication information 201. And the cyclic communication information 201 is added to this cyclic data 207 to form a cyclic data ATM cell 401, and the transmission ATM cell conversion unit 1
11 and the value obtained by taking the logical AND is “0000”, it is determined that the transmission is impossible and the cyclic communication information 20
Then, the processing is moved to the next cyclic communication information 201 indicated by the next information data address 202 in 1. In this manner, the contents of the transmission enable register 108 and the cyclic transmission control data 204 are logically ANDed to determine whether or not the cyclic data 207 can be transmitted for each cyclic data, and the cyclic transmission sequence is executed. .

As shown in FIG. 3, the cyclic transmission control data 204 includes, for example, four groups according to the type of cyclic data 207, that is, "0001",
It is classified into "0010", "0100", and "1000". The types of cyclic data 207 that are cyclically transmitted include, for example, pure cyclic data (control process input / output data, etc.) and station 10.
There are two pieces of RAS information and cyclic MAP information, which are grouped by setting a predetermined bit of the cyclic transmission control data 204 to "1" as described above. Then, the contents of the transmission enable register 108 of each station 102 corresponding to the cyclic transmission control data 204 according to the state and usage of a system such as a plant control system to which the cyclic communication control method according to the first embodiment is applied. Is operated via the host 106 to change enable / disable of transmission. For example, in a duplicated computer with one unit prepared for backup of the regular system, the regular computer transmits all the above-mentioned pure cyclic data, RAS information, and cyclic MAP information, but the standby system. The computer of 1 transmits only RAS information. In the case of a dual computer composed of such a regular computer and a standby computer, even if an abnormality occurs in the regular computer, the contents of the transmission enable register 108 are changed to change the transmission information storage memory 110. The normal system / standby system switching process can be executed without changing the cyclic transmission control data 204 of each cyclic communication information 201 therein. Since it takes time to change the cyclic transmission control data 204, it is possible to execute the switching process between the regular system and the standby system at higher speed by performing the above operation. Of course, the normal system / standby system switching process can be executed by changing the cyclic transmission control data 204.

Further, the cyclic transmission control data 204
Is assigned to the cyclic data transfer for test (diagnosis), and the cyclic data 207 for test is not transmitted during normal online, but the corresponding bit of the transmission enable register 108 is transmitted at the time of test (diagnosis). By setting up, the cyclic data 207 for test can be transferred. In this way, the cyclic transmission control data 204 is divided into groups, the contents of the transmission enable register 108 are set to values corresponding thereto, and the contents of the transmission enable register 108 are updated, thereby cyclically operating the system. It is possible to easily execute the control of the cyclic transmission sequence such as the change from the cyclic data transfer process in units of groups according to the type of data to the transfer process of all cyclic data, or vice versa.

Further, in the example shown in FIG. 3, when the cyclic transmission control data 204 is "1111", the cyclic transmission sequence is stopped regardless of the contents of the transmission enable register 108. Such control for stopping the cyclic transmission sequence is effective when only a small amount of cyclic data 207 is transmitted during a test or the like. In this way, by changing the content of the cyclic transmission control data 204 to, for example, “1111”, a small amount of cyclic data 20 can be used at the time of a test.
It is possible to easily confirm the soundness of the transmission operation by transmitting only 7.

As described above, in the cyclic communication control method according to the first embodiment, the cyclic transmission control data 204 and the contents of the transmission enable register 108 are compared to determine the transmission execution. The cyclic data 207 in which the information indicating that transmission is possible is set in the data 204 is transmitted, and the cyclic data 207 in which the information indicating that transmission is impossible is set in the cyclic transmission control data 204 is skipped and is not transmitted. Further, by changing the value of the transmission enable register 108, the transmission of all cyclic data 207 can be collectively controlled. Furthermore, cyclic transmission control data 2
By dividing the cyclic data 207 into a plurality of groups as described above corresponding to each bit of 04, cyclic data transfer processing can be executed in group units.
Further, the contents of the cyclic transmission control data 204 can be changed to predetermined contents and the cyclic transmission sequence can be stopped when the cyclic data is transmitted.

Next, the reception cyclic data storage control unit 1
The operation of 12 will be described with reference to FIG. The reception cyclic data storage control unit 112 receives the cyclic data ATM cell 40 from the reception ATM cell conversion unit 104.
When receiving notification of reception of 1, cyclic data ATM
The cyclic communication information 201 added by the transmitting station 102 is removed from the cell 401 to extract the cyclic data 207, and the cyclic communication information 201 is extracted.
The cyclic data address 205 to be stored is checked, and the received cyclic data 207 is stored in the cyclic memory 105. Thus, station 1
02 converts an ATM cell transmitted from another station 102 through a predetermined logical connection in accordance with the above cyclic data transfer processing into a cyclic data ATM cell 401, and then, its own which is a network shared memory space. The received cyclic data 207 is expanded in the same area in the cyclic memory 105.

As described above, according to the first embodiment, the cyclic transmission control data 204 set in the cyclic data unit and the transmission enable register 108 are provided to execute the transmission control. By appropriately updating at least one of the contents of the click transmission control data 204 and the transmission enable register 108, all cyclic data 207 can be obtained during system operation.
Control all transmissions of all cyclic data 20
7 or the cyclic data 207 can be selectively executed in units of types, and the effect of easily controlling the cyclic data transmission sequence such as switching between these transmissions can be obtained. Furthermore, since the cyclic transmission sequence can be stopped by changing the content of the cyclic transmission control data 204 to a predetermined value, only a small amount of cyclic data 207 can be transmitted at the time of a test or the like to improve the soundness of the transmission operation. The effect that can be easily confirmed is obtained.

Further, since the ATM is adopted, the control of the cyclic transmission sequence as described above can be easily realized by hardware, and at the same time, the performance of the cyclic data transmission amount and the data update period is improved and the transmission is performed. It is possible to minimize data discard when a frame check error occurs on the road.

In the first embodiment, the cyclic transmission control data 204 and the transmission enable register 108 are set.
And 4 bits each, but the present invention is not limited to this, and the number of bits is determined according to the usage of the system such as the plant control system to which the cyclic communication control method is applied. .

Embodiment 2. 6 is a block diagram showing a configuration of a station which is an example of a cyclic communication control method according to a second embodiment of the present invention and a cyclic communication device using the cyclic communication control method,
In the figure, the same parts as those in FIG. Further, in FIG. 6, a network shared memory space 601 is a transmission information storage cyclic memory (cyclic memory) for storing the cyclic communication information 201 and the cyclic data 207.

FIG. 7 shows a cyclic memory 6 for storing transmission information.
It is explanatory drawing which shows the structure of 01, In the figure, the same code | symbol is attached | subjected to the same part as FIG. 2, and the overlapping description is abbreviate | omitted. The transmission information storage cyclic memory 601 stores one or a plurality of cyclic communication information 201 and one or a plurality of cyclic data 207 respectively corresponding to each cyclic communication information 201. The cyclic data address 205 indicates the address of the cyclic data 207 in the transmission information storing cyclic memory 601. As described above, in the second embodiment, the area for storing the cyclic data 207 and the area for storing the cyclic communication information 201 are physically transmitted in a single transmission space that does not define the boundary between them. It is provided on the information storage cyclic memory 601.

Next, the operation will be described. In the following description, only the part different from the operation by the cyclic communication control method according to the first embodiment will be described, and the description of the same operation will be omitted. The cyclic data transmission format conversion control unit 1 which has been notified by the timer 107 that the transmission cycle has elapsed during cyclic data transmission.
Reference numeral 09 denotes the cyclic transmission control data 204 and the transmission enable register 1 included in the cyclic communication information 201 stored in the transmission information storing cyclic memory 601.
08, the transmission / non-transmission of the cyclic data 207 is determined, and when transmission is possible, the cyclic data is stored in the transmission information storage cyclic memory 601 by referring to the corresponding cyclic data address 205. 207 is taken out, and this cyclic data 20
The cyclic communication information 201 is added to 7 to create a cyclic data ATM cell 401, and the cyclic data ATM cell 401 is transmitted to the transmission ATM cell conversion unit 111.

Also in the second embodiment, as shown in FIG. 3, the cyclic data transmission format conversion control unit 109 takes the logical AND of the contents of the transmission enable register 108 and the cyclic transmission control data 204, The cyclic transmission control data 204 is “1111”
In other cases, the value obtained by logical AND is "000.
If it is not 0 ", it is possible to transmit and cyclic communication information 2
Based on the cyclic data address 205 in 01, the cyclic data 207 is taken out from the transmission information storing cyclic memory 601 and the cyclic data 20
7, the cyclic communication information 201 is added to create a cyclic data ATM cell 401, which is transmitted to the transmission ATM cell conversion unit 111, and the logical AND value is “000.
When it becomes 0 ", it is determined that the transmission is impossible, and the process is moved to the next cyclic communication information 201 indicated by the next information data address 202 in the cyclic communication information 201.

On the other hand, when the station 102 receives an ATM cell in the physical layer via the ATM switch 101, the line control unit 103 converts the physical layer into an ATM layer, and the received ATM cell is received by the receiving ATM cell converting unit 1.
Send to 04. The reception ATM cell conversion unit 104 recognizes the received ATM cell, removes the ATM cell header from the ATM cell, and removes the cyclic data ATM cell 401.
To the received cyclic data storage control unit 1
Notify 12 Received cyclic data storage control unit 1
12 is cyclic data ATM, as shown in FIG.
The cyclic communication information 201 is removed from the cell 401, the cyclic data address 205 to be stored is checked based on the cyclic communication information 201, and the cyclic data 207 is stored in the transmission information storing cyclic memory 601. As described above, the station 102 is not connected to the other stations 1 according to the cyclic data transfer process described above.
Cyclic data ATM cell 40 from the ATM cell transmitted from 02 via a predetermined logical connection.
After converting to 1, the received cyclic data 207 is expanded in the same area in the transmission information storage cyclic memory 601 which is the network shared memory space.

As described above, according to the second embodiment, in addition to the effects of the first embodiment described above, an area for storing cyclic data 207 and an area for storing cyclic communication information 201 are provided. Communication control is performed by placing the transmission memory on the transmission information storage cyclic memory 601 which is a physically continuous memory space that does not define the boundary. Therefore, regardless of the sizes of the cyclic communication information 201 and the cyclic data 207, these two are stored. The effect that the transmission information storing cyclic memory 601 can be used efficiently without being aware of the boundary of the area for storing information is obtained.

Embodiment 3. 9 is a block diagram showing a configuration of a station which is an example of a cyclic communication control method according to Embodiment 3 of the present invention and a cyclic communication device using the cyclic communication control method,
In the figure, the same parts as those in FIG. Further, in FIG. 9, reference numeral 901 denotes a test setting register for setting execution of the single loopback test of the cyclic communication function of the station 102 when performing the single loopback test of the cyclic communication function.

Next, the operation will be described. In the following description, only the part different from the operation by the cyclic communication control method according to the first and second embodiments will be described, and the description of the same operation will be omitted. Host 1
Reference numeral 06 sets a predetermined value indicating that the single loopback test of the cyclic communication function is to be performed in the test setting register 901 before performing the single loopback test of the cyclic communication function. The single loopback test of the cyclic communication function means that the cyclic data ATM cell 401 including the cyclic data 207 transmitted by the station 102 is received by itself to test whether or not the cyclic communication function is operating normally. To do.

An interface cable having a loopback function is connected to the line control unit 103, and the host 1
The line control unit 103 receives the cyclic data ATM cell 401 including the cyclic data 207 transmitted by the line control unit 103 under the control of the single loopback test of the cyclic communication function according to 06. Upon receiving the cyclic data ATM cell 401, the reception cyclic data storage control unit 112 determines that a single loopback test of the cyclic communication function is being performed based on the result of analysis of the contents of the test setting register 901,
As shown in FIG. 10, cyclic data ATM cell 4
The cyclic communication information 201 is removed from 01 to extract the cyclic data 207, and the cyclic data 2
All bits of 07 are inverted and inverted cyclic data 10
Create 01. Furthermore, cyclic communication information 201
The cyclic data address 205 in which the inverted cyclic data 1001 should be stored is checked, and the inverted cyclic data 1001 is transmitted.
Stored in 01. Therefore, in the single loopback test, the cyclic data 207 transmitted after being stored in the transmission information storing cyclic memory 601 is overwritten with the inverted cyclic data 1001 in which all bits of the received cyclic data 207 are inverted. Therefore, the transmitted cyclic data 207 and the inverted cyclic data 1001 received and stored in the same cyclic data address 205 are different for each bit if cyclic communication is normally performed.

On the other hand, cyclic data ATM cell 40
The host 106, which has recognized the reception of 1, transmits the inverted cyclic data 1 in the transmission information storing cyclic memory 601.
The value of 001 is read, and it is confirmed whether this is equal to the bit-inverted value of the value of the cyclic data 207 set and transmitted by the host 106. In this way, it is possible to carry out a single loopback test of the cyclic communication function and verify whether or not the cyclic communication is normally performed.

As described above, according to the third embodiment, the test setting register 901 which can be arbitrarily set is provided, and all bits of the cyclic data 207 received by the result of analysis of the contents of the test setting register 901. Is inverted and processed and stored in the transmission information storing cyclic memory 601. Therefore, during the single loopback test, even if the transmitted cyclic data 207 is received and the inverted reversed cyclic data 1001 is overwritten, the transmitted cyclic data is transmitted. Since the data 207 and the inverted cyclic data 1001 received and stored in the same cyclic data address 205 are cyclic data different for each bit, cyclic data 2 is used in the single loopback test.
It is possible to easily recognize that 07 has been received and to easily confirm the soundness of the transmission / reception operation in cyclic communication.

In the third embodiment, as in the second embodiment, the area for storing the cyclic data 207 and the area for storing the cyclic communication information 201 are physically defined without defining their boundaries. Although provided on the single transmission information storage cyclic memory 601 which is a continuous memory space, as in the first embodiment, an area for storing the cyclic data 207 and an area for storing the cyclic communication information 201 are provided. May be provided on another memory.

Fourth Embodiment FIG. 11 is an explanatory diagram showing the cyclic communication control method according to the fourth embodiment of the present invention and the disassembly and storage of the received cyclic data ATM cell 401 in the cyclic communication device using this cyclic communication control method. In the figure, 1101
Is cyclic data obtained by shifting the cyclic data 207 received during the single loopback test by 1 bit. The configuration of the station 102 to which the cyclic communication control method according to the fourth embodiment is applied is the same as that according to the third embodiment, and the duplicated description will be omitted.

Next, the operation will be described. In the following description, only the part different from the operation by the cyclic communication control method according to the third embodiment will be described, and the description of the same operation as that of the third and first embodiments will be omitted. When the reception cyclic data storage control unit 112 receives the cyclic data ATM cell 401, the reception cyclic data storage control unit 112 determines from the analysis result of the contents of the test setting register 901 that a single loopback test of the cyclic communication function is being performed, and FIG. As shown, the cyclic communication information 201 is removed from the cyclic data ATM cell 401 to extract the cyclic data 207, and all bits of the cyclic data 207 are shifted by 1 bit to generate 1-bit shift cyclic data 1101. To do. Further, the cyclic data address 205 in which the 1-bit shift cyclic data 1101 is to be stored is checked from the cyclic communication information 201, and the 1-bit shift cyclic data 1101 is stored in the transmission information storage cyclic memory 601.

On the other hand, cyclic data ATM cell 40
The host 106 that has recognized the reception of 1 reads the value of the 1-bit shift cyclic data 1101 in the transmission information storing cyclic memory 601 and this is the host 106.
It is confirmed whether or not the value of the cyclic data 207 set and transmitted by is equal to the value shifted by 1 bit. In this way, it is possible to carry out a single loopback test of the cyclic communication function and verify whether or not the cyclic communication is normally performed.

As described above, according to the fourth embodiment, similarly to the third embodiment, the test setting register 901 which can be arbitrarily set is provided, and the contents of the test setting register 901 are analyzed. All bits of the received cyclic data 207 are shifted by 1 bit and processed and stored in the transmission information storing cyclic memory 601. Therefore, during the single loopback test, the cyclic data 207 transmitted is received and shifted by 1 bit. 1
Even if the bit-shift cyclic data 1101 is overwritten, the cyclic data 207 transmitted is received and the 1-bit shift cyclic data 1101 stored in the same cyclic data address 205 is different cyclic data. Thus, it is possible to easily recognize that the cyclic data 207 has been received and to easily confirm the soundness of the transmission / reception operation in the cyclic communication.

In the fourth embodiment, similarly to the second embodiment, the area for storing the cyclic data 207 and the area for storing the cyclic communication information 201 are physically defined without defining their boundaries. Although provided on the single transmission information storage cyclic memory 601 which is a continuous memory space, as in the first embodiment, an area for storing the cyclic data 207 and an area for storing the cyclic communication information 201 are provided. May be provided on another memory.

Embodiment 5. 12 (a) and 12
(B) is an explanatory diagram showing the cyclic communication control method according to the fifth embodiment of the present invention and the disassembly and storage of the received cyclic data ATM cell 401 in the cyclic communication device using this cyclic communication control method. In the figure, 1102 is cyclic data 207 received during the single loopback test, which is cyclic data stored at an address obtained by adding a fixed number to the cyclic data address 205. This Embodiment 5
The configuration of the station 102 to which the cyclic communication control method according to is applied is the same as that according to the above-described third embodiment, and the duplicated description will be omitted.

Next, the operation will be described. In the following description, only the part different from the operation by the cyclic communication control method according to the third embodiment will be described, and the description of the same operation as that of the third and first embodiments will be omitted. When the reception cyclic data storage control unit 112 receives the cyclic data ATM cell 401, the reception cyclic data storage control unit 112 determines from the analysis result of the contents of the test setting register 901 that a single loopback test of the cyclic communication function is being performed, and FIG. As shown in a), cyclic data ATM cell 401 to cyclic communication information 2
01 is removed and the cyclic data 207 is extracted. Furthermore, the cyclic data address 205 is checked from the cyclic communication information 201, and as shown in FIG. 12B, the transmission of the extracted cyclic data 207 designated by an address obtained by adding a fixed number to the cyclic data address 205. Information is stored in the cyclic memory 601.

On the other hand, cyclic data ATM cell 40
The host 106 that has recognized the reception of 1 reads the value of the cyclic data 1102 stored in the transmission information storing cyclic memory 601 designated by the above-mentioned address obtained by adding a fixed number to the cyclic data address 205, and Cyclic data 2 set and transmitted by 106
It is confirmed whether the value of 07 matches. In this way, it is possible to carry out a single loopback test of the cyclic communication function and verify whether or not the cyclic communication is normally performed.

As described above, according to the fifth embodiment, the test setting register 901 that can be arbitrarily set is provided, and the cyclic data 207 received based on the result of analysis of the contents of the test setting register 901 is transmitted information. When storing in the storage cyclic memory 601, the cyclic data address 205 is shifted and stored by a fixed number of fixed ranges. Therefore, in the single loopback test, the transmitted cyclic data 207 is overwritten with the received cyclic data 207. Instead, the received cyclic data 207 can be easily recognized, and the soundness of the transmission / reception operation in cyclic communication can be easily confirmed.

In the fifth embodiment, similarly to the second embodiment, the area for storing the cyclic data 207 and the area for storing the cyclic communication information 201 are physically defined without defining their boundaries. Although provided on the single transmission information storage cyclic memory 601 which is a continuous memory space, as in the first embodiment, an area for storing the cyclic data 207 and an area for storing the cyclic communication information 201 are provided. May be provided on another memory.

Sixth Embodiment FIG. 13 is a block diagram showing a configuration of a station and a system which are examples of a cyclic data communication control method according to a sixth embodiment of the present invention and a cyclic communication device using this cyclic communication control method. 6, the same parts as those of FIG. In addition, FIG.
At 1301, a cyclic transmission control register 1301 is set with a predetermined value from the host 106 in order to stop the operation of the transmission ATM cell conversion unit 111, and 1302 is a transmission A.
An emergency stop external input unit 1303 in which a predetermined emergency stop signal is applied from the outside to set the predetermined value to stop the operation of the TM cell conversion unit 111 is a system including the station 102.

Next, the operation will be described. In the following description, only the part different from the operation by the cyclic communication control method according to the second embodiment will be described, and the description of the same operation as the second embodiment will be omitted. First, the operation stop process of the transmission ATM cell conversion unit 111 using the cyclic transmission control register 1301 will be described. When an important problem that cannot be restored occurs in the station 102, the host 106 sets a value that is set in advance as an emergency stop in the cyclic transmission control register 1301. Cyclic transmission control register 1301
When this value, which is defined as an emergency stop of the station 102, is set in the cyclic transmission control register 13
01 issues a transmission stop request for the cyclic data ATM cell 401 to the transmission ATM cell conversion unit 111, and transmits the transmission ATM cell 401.
The cell conversion unit 111 immediately stops the cyclic transmission sequence.

Next, the emergency stop external input section 1302 will be described. System 1303 including station 102
When an important problem that cannot be recovered occurs in the station 102 or when the host 106 cannot operate normally in the station 102, an emergency stop signal indicating an emergency stop is applied from the system 1303 to the emergency stop external input unit 1302. The emergency stop external input unit 1302 issues a transmission stop request for the cyclic data ATM cell 401 to the transmission ATM cell conversion unit 111, and the transmission ATM cell conversion unit 111 immediately stops the cyclic transmission sequence.

As described above, according to the sixth embodiment, the cyclic transmission control register 1301 and the emergency stop external input section 1302 are provided, and the cyclic transmission control is performed by referring to the respective states. Control register 1301 or emergency stop external input unit 1302
Since the control for forcibly stopping the cyclic transmission sequence is performed when is enabled, the cyclic transmission sequence can be easily stopped when the station 102, the system 1303, or the host 106 fails, and the influence on the external network is prevented. The effect that can be suppressed is obtained.

In the sixth embodiment, as in the second embodiment, the area for storing the cyclic data 207 and the area for storing the cyclic communication information 201 are physically defined without defining their boundaries. Although provided on the single transmission information storage cyclic memory 601 which is a continuous memory space, as in the first embodiment, an area for storing the cyclic data 207 and an area for storing the cyclic communication information 201 are provided. May be provided on another memory.

Embodiment 7. 14 is a block diagram showing a configuration of a station which is an example of a cyclic data communication control method according to Embodiment 7 of the present invention and a cyclic communication device using this cyclic communication control method, and in FIG. The same parts as those in FIG. In addition, in FIG.
01 is a cyclic data ATM cell 401 at the time of transmission
CRC (Cyclic Redundancy Check) information is added to to create a cyclic data ATM cell with CRC information, and this is transmitted to the transmission ATM cell conversion unit 111, and when receiving the CRC
A CRC generation / check unit that checks the soundness of the data of the cyclic data ATM cell 401 based on the information,
A reception ATM cell buffer 1402 temporarily stores the cyclic data ATM cell 401 from which the CRC information has been removed from the received cyclic data ATM cell with CRC information.

Next, the operation will be described. In the following description, only the part different from the operation by the cyclic communication control method according to the second embodiment will be described, and the description of the same operation as the second embodiment will be omitted.

At the time of ATM cell transmission, the CRC generation / check unit 1401 transmits the cyclic data AT transmitted from the cyclic data transmission format conversion control unit 109.
When the M cell 401 is received, as shown in FIG. 15, CRC information 1501 is generated according to the error detection polynomial and added to the cyclic data ATM cell 401 to create a cyclic data ATM cell 1502 with CRC information.

On the other hand, when an ATM cell is received, the reception ATM cell conversion section 104 recognizes the received ATM cell and
The ATM cell header is removed from the M cell to convert it into the cyclic data ATM cell 1502 with CRC information, and the cyclic data ATM cell 1502 with CRC information is converted into the cyclic data ATM cells 401 and C.
It is separated into RC information 1501 and notified to the reception cyclic data storage control unit 112, and as shown in FIG. 16, the cyclic data ATM cell 401 and the CRC information 1501 are transmitted to the CRC generation / check unit 1401 and received. The cyclic data ATM cell 401 is temporarily stored in the ATM cell buffer 1402. CRC generation /
The checking unit 1401 receives the cyclic data A
CRC calculation is performed on the TM cell 401 according to the error polynomial, and the calculation result and the CRC information 1501 are compared to confirm that they are the same. If they are not the same, the size stored in the reception ATM cell buffer 1402 is stored. The click data ATM cell 401 is erased.

On the other hand, CRC generation / check unit 1401
When the above calculation result and the CRC information 1501 are the same, the cyclic data ATM cell 401 in the reception ATM cell buffer 1402 is regarded as valid and is not erased and is left as it is. When the cyclic data ATM cell 401 is not erased in this way, the reception cyclic data storage control unit 112 extracts the cyclic data ATM cell 401 from the reception ATM cell buffer 1402 and then cyclic communication information 201.
Of the cyclic communication information 201, the cyclic data address 205 is checked from the cyclic communication information 201, and the cyclic data address 205 is stored in the transmission information storage cyclic memory 601.

Further, in the CRC generation / check unit 1401, when the generation of CRC information at the time of transmission and the request for checking the CRC information at the time of reception occur at the same time and there is a conflict,
The transmission cycle is secured by giving priority to the CRC information generation.

As described above, according to the seventh embodiment, the CRC information 150 is calculated according to the CRC error detection polynomial.
A CRC generation / check unit 1401 that can be configured by a single piece of hardware having a function of generating 1 is shared by the transmission / reception units, and this CRC generation / check unit 1401
Controls the validity of the received cyclic data 207 based on the CRC information 1501 when the cyclic data is transmitted, and also adds the CRC information 1501 when transmitting the cyclic data, so that the quality of the cyclic data 207 can be secured with less hardware. The effect can be obtained.

In the seventh embodiment, as in the second embodiment, the area for storing the cyclic data 207 and the area for storing the cyclic communication information 201 are physically defined with no boundary. Although provided on the single transmission information storage cyclic memory 601 which is a continuous memory space, as in the first embodiment, an area for storing the cyclic data 207 and an area for storing the cyclic communication information 201 are provided. May be provided on another memory.

[0079]

As described above, according to the invention described in claim 1, when the cyclic communication control method executes the cyclic transmission sequence, the cyclic transmission control data is transmitted.
And the contents of the transmission enable register are compared to determine whether or not cyclic data should be transmitted for each cyclic data. If the cyclic data is to be transmitted, when it is received by another station, Control information necessary for writing cyclic data on its own cyclic memory is added to each cyclic data A
Since the TM cell is configured to be created, the cyclic transmission control data is arbitrarily updated to collectively control the transmission of all the cyclic data during the operation of the system including a plurality of stations, and all the cyclic data are controlled. Transmission of click data or transmission of each type of cyclic data can be selected and executed, and further, the cyclic transmission sequence can be controlled so as to switch these transmissions.

According to the second aspect of the invention, the cyclic communication control method is constructed so that an ATM cell is created and transmitted when a predetermined transmission cycle preset for transmitting an ATM cell as a CBR elapses. Therefore, it is possible to control the cyclic transmission sequence with a simpler hardware configuration.

According to the third aspect of the invention, in the cyclic communication control method, the cyclic transmission control data is composed of at least one bit, and it is determined whether transmission is possible or not according to the contents of the cyclic transmission control data. It is configured to determine whether or not to transmit cyclic data for each cyclic data by providing a transmission enable register for performing cyclic comparison and comparing the cyclic transmission control data with the contents of the transmission enable register. ,
By optionally updating at least one of the contents of the transmission enable register and the cyclic transmission control data, the cyclic transmission sequence is controlled so that cyclic data units or all cyclic data are transmitted during system operation. There is an effect that can be.

According to the fourth aspect of the invention, the cyclic communication control method uses the cyclic transmission control data and the contents of the transmission enable register by performing a predetermined logical operation and determining the operation result. Since it is configured to judge whether or not cyclic data should be transmitted for each click data, at least one of the contents of the transmission enable register and cyclic transmission control data can be arbitrarily updated to perform a simple logical operation. By doing so, there is an effect that the cyclic transmission sequence can be controlled so as to transmit the cyclic data unit or all cyclic data during system operation.

According to the fifth aspect of the invention, the cyclic communication control method is configured such that the cyclic transmission control data is classified into a plurality of groups according to the type of cyclic data. By setting or updating the contents of the transmission enable register according to the data, change from the transfer processing of all cyclic data to the cyclic data transfer processing of the group unit according to the type of cyclic data during system operation, or There is an effect that the control in the cyclic transmission sequence such as the opposite change can be easily executed.

According to the sixth aspect of the present invention, the cyclic communication control method means that the cyclic transmission sequence is stopped by a predetermined value of the cyclic transmission control data, and the cyclic transmission control is performed when the cyclic transmission sequence is executed. Since the cyclic transmission sequence is configured to stop if the data is at the specified value, by changing the contents of the cyclic transmission control data, only a small amount of cyclic data is transmitted during testing, etc. There is an effect that the soundness of the transmission operation can be easily confirmed.

According to the invention described in claim 7, the area for storing the control information necessary for reflecting the cyclic data received by another station in the cyclic communication control method in its own cyclic memory is cyclic. Since the configuration is provided on the click memory, the cyclic memory can be used efficiently without being aware of the boundary between the two regardless of the control information for transmitting the cyclic data and the size of the cyclic data. There is an effect that can be done.

According to the invention described in claim 8, the cyclic communication control method receives the cyclic data transmitted by the station itself during the single loopback test, and inverts all the bit values of the received cyclic data. The cyclic data is written in the cyclic memory, so that it is possible to easily recognize that the cyclic data is received during the single loopback test, and it is possible to easily confirm the soundness of the transmission / reception operation in the cyclic communication.

According to the invention described in claim 9, the cyclic communication control method receives cyclic data transmitted by the station itself during a single loopback test, and shifts the value of the received cyclic data by 1 bit. Since the data is written in the cyclic memory, it is possible to easily recognize that the cyclic data is received during the single loopback test, and it is possible to easily confirm the soundness of the transmission / reception operation in the cyclic communication.

According to the tenth aspect of the invention, the cyclic communication control method receives the cyclic data transmitted by the station itself during the single loopback test, and sets the address at which the received cyclic data should be stored to a predetermined value. Since the data is shifted and written in the cyclic memory, it is possible to easily recognize that the cyclic data has been received during the single loopback test and to easily confirm the soundness of the transmission / reception operation in the cyclic communication.

According to the eleventh aspect of the present invention, the values of all the bits of the cyclic data received according to the contents of the test setting register that can set the cyclic communication control method from the host of the station are inverted, Alternatively, since the value is shifted by 1 bit or the address to be stored is shifted by a predetermined value and written to the cyclic memory, it is possible to use the test setting register to check that cyclic data has been received during the single loopback test. It has an effect that it can be easily recognized and the soundness of the transmission / reception operation in the cyclic communication can be easily confirmed.

According to the twelfth aspect of the present invention, the cyclic communication control method is configured to forcibly stop the cyclic transmission sequence in response to a request from the host of the station. The effect is that the cyclic transmission sequence can be easily stopped and the influence on the external network can be suppressed.

According to the thirteenth aspect of the present invention, the cyclic communication control method is configured to forcibly stop the cyclic transmission sequence according to the emergency stop signal input from the outside of the station. The cyclic transmission sequence can be easily stopped when the external system fails, and the effect on the external network can be suppressed.

According to the fourteenth aspect of the invention, in the cyclic communication control method, CRC information is added to the cyclic data when transmitting the cyclic data, and the validity of the cyclic data based on the CRC information when receiving the cyclic data. Since it is configured to discard the cyclic data if the received cyclic data is not valid, there is an effect that the quality of the cyclic data can be secured with a small amount of hardware.

According to the fifteenth aspect of the present invention, cyclic transmission control is performed when cyclic data stored in the cyclic communication device is transmitted to another cyclic communication device via the ATM switch. Cyclic data transmission determining means for determining whether or not to transmit cyclic data for each cyclic data by comparing the data with the contents of the transmission enable register, and if the cyclic data is to be transmitted, ATM cell creating means for creating an ATM cell by adding control information necessary for writing cyclic data received by another cyclic communication device to its own cyclic memory for each cyclic data The configuration of the transmission enable register and cyclic transmission control data By updating optionally either even without an effect capable of controlling the cyclic transmission to transmit the cyclic data unit or all cyclic data during system operation.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a station which is an example of a cyclic communication control method according to a first embodiment of the present invention and a cyclic communication device using the cyclic communication control method.

FIG. 2 is a diagram showing data storage in a transmission information storage memory and a cyclic memory in the cyclic communication control method according to the first embodiment of the present invention.

FIG. 3 is an explanatory diagram showing an example of transmission control according to the contents of a transmission enable register and cyclic transmission control data in the cyclic communication control method according to the first embodiment of the present invention.

FIG. 4 is an explanatory diagram showing a process of creating a cyclic data ATM cell in the cyclic communication control method according to the first embodiment of the present invention.

FIG. 5 is an explanatory diagram showing a process of disassembling and storing cyclic data ATM cells in the cyclic communication control method according to the first embodiment of the present invention.

FIG. 6 is a block diagram showing a configuration of a station which is an example of a cyclic communication control method according to a second embodiment of the present invention and a cyclic communication device using the cyclic communication control method.

FIG. 7 is an explanatory diagram showing data storage in a transmission information storage cyclic memory in the cyclic communication control method according to the second embodiment of the present invention.

FIG. 8 is an explanatory diagram showing a process of disassembling and storing cyclic data ATM cells in the cyclic communication control method according to the second embodiment of the present invention.

FIG. 9 is a block diagram showing a configuration of a station which is an example of a cyclic communication control method according to the third, fourth and fifth embodiments of the present invention and a cyclic communication device using the cyclic communication control method.

FIG. 10 is an explanatory diagram showing a process of disassembling and storing cyclic data ATM cells in the cyclic communication control method according to the third embodiment of the present invention.

FIG. 11 is an explanatory diagram showing a process of disassembling and storing cyclic data ATM cells in the cyclic communication control method according to the fourth embodiment of the present invention.

FIG. 12 is an explanatory diagram showing a process of disassembling and storing cyclic data ATM cells in the cyclic communication control method according to the fifth embodiment of the present invention.

FIG. 13 is a block diagram showing a configuration of a station and a system which are examples of a cyclic communication control method and a cyclic communication device using the cyclic communication control method according to a sixth embodiment of the present invention.

FIG. 14 is a block diagram showing a configuration of a station which is an example of a cyclic communication control method and a cyclic communication device using the cyclic communication control method according to a seventh embodiment of the present invention.

FIG. 15 is an explanatory diagram showing a process of creating a cyclic data ATM cell with CRC information in the cyclic communication control method according to the seventh embodiment of the present invention.

FIG. 16 is an explanatory diagram showing a CRC check method and a process of disassembling and storing cyclic data ATM cells in the cyclic communication control method according to the seventh embodiment of the present invention.

FIG. 17 is a block diagram showing an example of a conventional cyclic communication control method and a conventional cyclic communication device.

[Explanation of symbols]

101 ATM switch, 102 station, 104
Reception ATM cell conversion unit (ATM cell reception means), 10
5 cyclic memory, 106 host, 108 transmission enable register, 109 cyclic data transmission format conversion control unit (cyclic data transmission determination means, ATM cell creation means), 110 transmission information storage memory (transmission information storage means), 111 transmission ATM cell conversion unit (ATM cell creation means), 112 reception cyclic data storage control unit (ATM cell reception means), 201
Cyclic communication information (control information), 204 cyclic transmission control data, 207 cyclic data, 6
01 Transmission information storage cyclic memory (cyclic memory), 901 test setting register, 1501 C
RC information.

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-2-186741 (JP, A) JP-A-7-254903 (JP, A) JP-A-2-123850 (JP, A) JP-A-7- 254901 (JP, A) JP 4-331525 (JP, A) JP 5-95365 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H04L 12/00 G06F 13 / 00 353 H04Q 9/00

Claims (15)

(57) [Claims] 1. A cyclic transmission control data is provided for each cyclic data stored in a cyclic memory of a station, and a cyclic transmission sequence for transmitting the cyclic data to another station via an ATM switch is executed. At this time, the cyclic transmission control data and the contents of the transmission enable register are compared to determine whether or not the cyclic data should be transmitted for each cyclic data, and the cyclic data to be transmitted is determined. If it is the click data, the control information necessary for writing the cyclic data on its own cyclic memory when received by the other station is added to each cyclic data to create an ATM cell. , The ATM cell is transmitted to the ATM exchange, and the ATM cell containing cyclic data is transmitted. When receiving from another station via the ATM switch, cyclic communication control for extracting the cyclic data from the ATM cell and writing the cyclic data in the cyclic memory based on the added control information. Method. 2. The cyclic according to claim 1, wherein a predetermined transmission cycle is set in advance for transmitting an ATM cell as a CBR, and when the transmission cycle elapses, the ATM cell is created and transmitted. Communication control method. 3. The cyclic transmission control data is composed of at least one bit, and a transmission enable register for determining whether transmission is possible or not according to the contents of the cyclic transmission control data is provided, and the cyclic transmission is performed. The control data and the contents of the transmission enable register are compared to determine whether or not the cyclic data should be transmitted for each cyclic data. Click communication control method. 4. Should the cyclic data be transmitted for each cyclic data by performing a predetermined logical operation on the cyclic transmission control data and the contents of the transmission enable register and judging the operation result? The cyclic communication control method according to claim 3, wherein it is determined whether or not there is any. 5. The cyclic communication control method according to claim 3 or 4, wherein the cyclic transmission control data is classified into a plurality of groups according to the type of cyclic data. 6. A predetermined value of the cyclic transmission control data means stop of the cyclic transmission sequence, and when the cyclic transmission sequence is executed, it is determined whether or not the cyclic transmission control data has the predetermined value. The cyclic communication control method according to claim 5, wherein the cyclic transmission sequence is stopped if the predetermined value is reached. 7. The cyclic memory is provided with an area for storing control information necessary for reflecting cyclic data received by another station in its own cyclic memory. The cyclic communication control method according to any one of claims 1 to 6. 8. The cyclic data transmitted by the station itself is received during the single loopback test, and all bit values of the received cyclic data are inverted and written in the cyclic memory. The cyclic communication control method according to any one of claims 1 to 7. 9. The cyclic data transmitted by the station itself is received during the single loopback test, and the value of the received cyclic data is shifted by 1 bit and written in the cyclic memory. 8. The cyclic communication control method according to claim 7. 10. A single loopback test is characterized in that the cyclic data transmitted by the station itself is received, and the address at which the received cyclic data is stored is shifted by a predetermined value and written in the cyclic memory. The cyclic communication control method according to any one of claims 1 to 7. 11. A test setting register which can be set from the host of the station and which is set to a predetermined value during a single loopback test is provided, and all bits of the cyclic data received according to the contents of the test setting register are stored. 11. The value is inverted, or the value is shifted by 1 bit, or the address to be stored is shifted by a predetermined value and written in the cyclic memory, and any one of claims 8 to 10 is written. The cyclic communication control method described in the item. 12. The cyclic communication control method according to claim 1, wherein the cyclic transmission sequence is forcibly stopped in response to a request from the host of the station. . 13. The cyclic communication control method according to claim 12, wherein the cyclic transmission sequence is forcibly stopped in response to an emergency stop signal input from the outside of the station. 14. When cyclic data is transmitted, CRC (Cyclic Redundancy Check) information is added to the cyclic data, and when cyclic data is received, the validity of the cyclic data is verified based on the CRC information, and the received cyclic data is received. The cyclic communication control method according to any one of claims 1 to 13, wherein the cyclic data is discarded if is not valid. 15. Transmission information storage means for storing cyclic transmission control data designated for each cyclic data stored in the cyclic memory, and whether transmission is possible or not according to the contents of the cyclic transmission control data. And a content of the transmission enable register for comparing the cyclic transmission control data with the content of the transmission enable register when transmitting the cyclic data to another cyclic communication device through an ATM switch. Cyclic data transmission determination means for determining whether or not to transmit the cyclic data for each cyclic data, and if the cyclic data to be transmitted, if the other cyclic communication device has received Control information required to write cyclic data on its own cyclic memory Is added to each cyclic data to create an ATM cell, and when an ATM cell containing cyclic data is received from another cyclic communication device via the ATM switch, the A
A cyclic communication device comprising ATM cell receiving means for extracting the cyclic data from a TM cell and writing the cyclic data in the cyclic memory based on the added control information.