JP3392643B2 - Signal transmission method in ring network - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ring network in which, for example, a factory automation controller and its input / output device are connected to a ring network to perform data transmission between the controller and the input / output device. The present invention relates to a signal transmission method.

[0002]

2. Description of the Related Art A token passing method is generally used as a signal transmission method in a conventional ring network. This token passing system circulates a transmission right frame called a token on the network, and a station wanting to transmit data acquires the token and transmits the data by adding a source address and a destination address,
When the data transmission is completed, the token will be released to the network again.

[0003]

However, in the above token passing system, when transferring data, in addition to the data to be sent, additional information such as the token frame or the address information of the data frame must be sent at the same time. Therefore, when constructing a system such as factory automation, there is an unsolved problem that transmission efficiency decreases.

That is, the data transmission efficiency is expressed by A / (A + B) where A is the length of data to be sent and B is the length of tokens and other unnecessary parts. For this reason,
If the data length A to be sent is much larger than the length B of the additional information, the transmission efficiency will not be so low, but the data transfer amount in the industrial field such as factory automation to which the present invention is applied depends on the input / output device. Output devices and relays that control on / off devices such as relays and switches,
In many cases, it is composed of an input device such as a switch for inputting a status signal. For example, the amount of data transmitted from the input / output device to the controller is as small as several bytes per transfer.
The influence of the length B of the additional information on the transmission efficiency becomes very large.

Further, usually, more than ten to several tens of input / output devices are connected to one network for data transmission in one system, and therefore the transmission efficiency of the entire network is {A / ( A + B)} × n (n is the number of connected devices), which further decreases. Therefore, the present invention has been made by paying attention to the unsolved problem of the above-mentioned conventional example, and it is possible to secure high transmission efficiency even when the amount of transmission data between the input / output device and the control device is small. It is intended to provide a signal transmission method in a ring network.

[0006]

To achieve the above object, according to an aspect of the signal transmission method in the ring network according to claim 1 includes a plurality of output devices for outputting a control signal to the control device, the control device A plurality of input devices for inputting control state signals of the control device and a plurality of control devices for sending control data to the output devices while monitoring the states of the respective control devices based on the control state signals from the input devices. In a signal transmission method in a ring network connected to a ring network so as to perform signal transmission between each control device and each output device and input device, the only master control among the plurality of control devices A master selection means for selecting a device is provided, and the control device selected by the master selection means collects connection information of each device connected to the ring network. Connection information collecting means, and a format deciding means for deciding a format of a transmission frame for exchanging data between each control device and each output device and input device based on the connection information collected by the connection information collecting device. And a data access position designating means for designating an individual data access position on the transmission frame when the transmission frame is received to each output device, the input device and the control device based on the format determined by the format determining device. And a frame transmitting means for generating a transmission frame according to the format determined by the format determining means and transmitting the frame to the ring network, and a frame transmitted by the frame transmitting means is the second round. If it is the first round, the frame is circulated as it is, 2 When it is an eye, it comprises a frame removing means for removing the transmission frame from the ring-shaped network after taking in the necessary data in the data, and the device other than the master control device receives the transmission frame for the first time. Writing data to a data access position designated by the data access position designating means of the master control device and fetching data at the data access position designated by the data access position designating means when the data is received in the second cycle. Is characterized by.

According to a second aspect of the present invention, there is provided a signal transmission system in a ring network, comprising a plurality of output devices for outputting control signals to a control device, and a plurality of input devices for inputting control state signals of the control device. A plurality of control devices that send control data to the output device while monitoring the state of each control device based on a control state signal from the input device are connected to a ring network, In a signal transmission method in a ring network adapted to perform signal transmission between each output device and each input device, a master selection means for selecting only one master control device from the plurality of control devices is provided, and the master The control device selected by the selecting means is a connection information collecting means for collecting connection information of each device connected to the ring network, and the connection information. A virtual format determining means for determining a virtual format of a transmission frame for transmitting and receiving data between each control device and each output device and input device based on the connection information collected by the collecting means; Data access position indicating means for indicating an individual data access position on a transmission frame when the transmission frame is received to each output device, input device and control device based on the determined virtual format, and the virtual format determination Frame transmission means for generating the transmission frame in which the control data for each output device is written according to the virtual format determined by the means, and transmitting the frame to the ring network; and the frame transmitted by the frame transmission means , It is judged whether it is the second round, and when it is the first round, The control device other than the master control device receives the transmission frame first, and includes a data capturing means for circulating the frame as it is and capturing the required data in the transmission frame in the second cycle. Sometimes, data is added to the data access position designated by the data access position designating means of the master control device, and when the data is received in the second cycle, the data at the data access position designated by the data access position designating means is similarly added. Each of the input devices takes in data and writes the data at the data access position designated by the data access position designating means of the master control device when the transmission frame is first received, and each output device makes two rounds of the transmission frame. The data access designated by the data access position designating means of the master control device when received by the eye. It is characterized in that a frame removing means for taking in the control data of the network position and further for removing the third round transmission frame from the ring network is provided in any device connected to the ring network.

Further, the signal transmission method in the ring network according to claim 3 is the signal transmission method according to claim 2 , wherein the control device and the output device including the master control device perform the virtual transmission when first circulating a transmission frame. Data is added to a data access position according to the virtual format determined by the format determining means, and when the transmission frame is circulated in the second cycle, the data added by itself is deleted and circulated. Is characterized by.

Furthermore, the signal transmission method in the ring network according to a fourth aspect is the signal transmission method according to the second aspect , wherein the control device including the master control device and the input device perform transmission when first circulating a transmission frame. It is characterized in that write data is added to the head of the data portion of the frame, and when the transmission frame is circulated in the second cycle, the data added by itself is deleted and circulated.

Still further, the signal transmission method in the ring network according to claim 5 is the signal transmission method according to claim 2 , wherein the control device including the master control device and the input device firstly circulate a transmission frame. It is characterized in that write data is added to the end of the data portion of the transmission frame, and when the transmission frame is circulated in the second cycle, the data added by itself is deleted and circulated.

Further, a signal transmission system in a ring network according to a sixth aspect is characterized in that, in any one of the second to fifth aspects, the frame removing means is provided in a master control device. . Further, the signal transmission method in the ring network according to claim 7 is the invention according to any one of claims 2 to 5 , wherein the frame removing means is added to the end of the control device and the input device other than the master control device. It is characterized in that it is provided in a device for deleting data.

Furthermore, a signal transmission system in a ring network according to an eighth aspect is the signal transmission method according to any one of the first to seventh aspects, wherein at least an output device, an input device, and a control device connected to the ring network. 1
It is characterized in that a delay means for delaying the received frame is inserted on one data receiving side.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a schematic configuration of a first embodiment of the present invention. Two output devices SO ₁ and SO ₂ for outputting a signal for controlling on / off devices such as a relay and a switch , and a relay, Two input devices SI1 and SI for inputting status signals of on / off devices such as switches
₂ and output command data to each of the output devices SO ₁ and SO ₂ to control the on / off devices, and also indicate the state of the on / off devices from each of the input devices SI ₁ and SI _2. crowded collected state data control device CR ₁ for two factory automation realized by the computer for monitoring such system, CR ₂ and is a control device CR ₁
As an upstream, an output device S that sequentially forms stations on the downstream side
O ₁ , input device SI ₁ , control device CR ₂ , input device SI
₂ and the output device SO ₂ are connected in a ring shape by a transmission line T so that a ring network is constructed.

The two control devices CR ₁ and CR ₂
Executes the processing of FIG. 2 , and first, at step S21, it determines whether or not it is the master control device. For this determination, for example, a hardware switch for master selection is provided in advance in each of the control devices CR 1 and CR ₂ , and only one of these hardware switches is turned on, so that the hardware switch of its own is switched. Is determined to be the master control device by determining whether or not the switch is in the ON state.

The control device in which the hardware switch is in the off state moves to step S22, starts the transmission process similar to the transmission process of the output device and the input device of FIG. 5 described later, and then ends the process. The control device in which the hardware switch is in the ON state moves to step S23. In this step S23, the connection to the ring network is made.
Collect the connection information to understand the configuration of each station.
This process is based on the structure of the frame sent on the network.
Is the collection of information needed to determine
Station configuration and number, that is, how many output devices are connected and how many input devices are connected
The location of connections between these stations
That is, in which order from the control device CR to the downstream side
Check if the connection is established, and
Connection information such as allocation of write information and read information held by each station
It collects information.

Collection of these connection information is controlled in advance, for example.
It is stored in a predetermined memory area in the ROM of the device CR,
When the controller CR powers up and starts up
Automatically read the connection information in or called a loader
Control equipment using the existing engineering support equipment
Transfer the connection information manually when the activation of the device CR is confirmed
You may do it.

Further, it is connected to the network in advance.
Assign an address to each station, as shown in Fig. 3.
In, connect the loader LR to the master control unit CR _M, control
When the device CR is activated, loader LR is manually
Transferring the connection information and address information to the control unit CR _M from
And, the control device CR _M receives the connection information and address information
If you take it, the information of your own station will be transferred to each station in order.
A command frame that prompts you to
Sent to sending passage 1, each station on the network frame Ndofure
The address and the address of your own station
Comparison, when both are coincident with the control device CR _M
Send the connection information of your own station and
If the address does not match your own address,
To relay the command frame of
More you can not receive the connection information in the control device CR _M station there
If the corresponding station corresponding to the address is on the network
It is possible to connect to the network due to the above abnormality or abnormality of each station.
The connection information from the loader LR is different from the connection information.
You can be sure that you know that
it can.

Next, in step S24, the format of the transmission frame F is determined. At this time, the output device S to be managed by the _two control devices CR ₁ and CR ₂
O _i (i = 1, 2) and input device SI _j (j = 1, 2)
Is the differ is configured as shown in FIG. 4, in the case of access to the control device CR ₁ and CR ₂ two common output device SO _i, control data for the output device SO _i It is set separately for two different data areas.

An example of the format of this transmission frame F is
As shown in FIG. 4, the start header indicating the beginning of the frame
Mita section SD and frame control section FC indicating the frame type
And the data section DT and the frame check for inspecting the frame.
Check sequence part FCS and the end of the frame
It is composed of a delimiter unit ED. And the data
The contents of the part DT, that is, the data and the data length, are described above.
Network connection information. This first
In the embodiment, as described above, the downstream side of the control device CR.
An output device SO ₁ , an input device SI ₁ , a control device CR ₂ ,
The input device SI ₂ and the output device SO ₂ are sequentially connected normally.
When it is set, the contents of the data part DT are output at the beginning.
Data area where the read data amount for the device SO ₁ is A byte
Set the area DT ₁ and write to the input device SI ₁ sequentially .
Data area DT _{2 with} embedded data amount of B bytes , input device S
Data area DT in which the write data amount for I ₂ is C bytes
₃ , and the amount of read data for the output device SO ₂ is D
The respective data areas DT ₄ of the printer are set.

Then, the process proceeds to step S25, in which the control device other than the own station, that is, the control device CR ₂ other than the master control device based on the determined format of the transmission frame F.
And the output devices SO ₁ and SO ₂ and the input devices SI _{1 and} SI ₂ are notified of the access position information for the transmission frame F and the access position information including the data length. Where the access position
The access position included in the information is, for example, the transmission frame F.
From the beginning (immediately after the start delimiter SD)
Expressed as a number. Therefore, the access position for each station
The information indicates the data length of the frame control unit FC, for example, 1 byte.
, The access position of the output device SO ₁ is 1 byte.
Preparative process type is set to reading processing, the input device SI ₁
The access position is output to 1 byte of the frame controller FC.
Value obtained by adding the amount of data in the SO _{1 area} , A bytes, A + 1 byte
The process type is set to write process, and the subsequent input device SI ₂
Access position of the input device SI _{1 in} the A + 1 byte
Value A + B + 1 bytes with data amount B added
For the output device SO ₂ that is set to the writing process,
Access position is A + B + C + 1 bytes and processing type is read
Reasonably set.

Then, in step S26, the control data for the output device SO ₁ and / or SO ₂ managed by itself is written in the data area of the determined format to generate the transmission frame F, which is then transmitted to the transmission buffer. In the output buffer SO on the downstream side of the transmission frame F stored in the transmission buffer.
Send to ₁ .

Next, in step S28, it is determined whether or not the transmission frame F that has made a round has been received. If the transmission frame F has not been received, the transmission frame F is waited until it is received, and the transmission frame F is received. Sometimes step S
Move to 29. In this step S29, the status data of the data area required by the data portion DT in the transmission frame F is read, and then the process proceeds to step S30 to transfer the received transmission frame F to the downstream output device SO ₁ again. Send out.

Next, in step S31, it is determined whether or not the transmission frame F that has gone through two rounds is received. If the transmission frame F is not received, the transmission frame F is waited until it is received, and the transmission frame F is received. If you do step S
Move to 32. In the step S32, it returns a transmission frame F is received after removing from the network to the step S26.

[0024] In this case, in Step S32, after removal of the transmission frame F from the network, by interposing a timer process, it is possible to transmit the transmission frame F periodically and treated in a step S 32 Can be terminated and the transmission of the transmission frame F can be triggered by an event by an interrupt or the like. The master controller CR _M
Output device SO ₁ and the control device CR ₂ except, SO ₂ and an input device SI _1, SI ₂ executes a transmission process of FIG. The transmission processing, first, at step S41, waits from the master controller CR _M to determine whether it has received a transmission frame including the access position information addressed to itself, receives when not receiving a transmission frame When it is received, the process proceeds to step S42, and the access position information is set in the read counter circuit 19 or the write counter circuit 29 of the transmission control circuit 10 described later.

Next, in step S43, it is determined whether or not there is transmission data to the output devices SO ₁ and SO ₂ and the control device CR ₁ and / or CR _{2. If} there is transmission data, the process proceeds to step S44. After shifting to store the transmission data in the output buffer 16 which will be described later, the flow shifts to step S45.
Move to 45.

In step S45, it is determined whether or not the transmission frame F is received. When the transmission frame F is not received, the process waits until it is received. When it is received, the process proceeds to step S46a to receive N times. Is incremented, the process proceeds to step S46b, and it is determined whether the number of times of reception N is "1". When the number of receptions N of the transmission frame F is “1”, it is determined that the transmission frame F is received for the first time, the process proceeds to step S47, and the transmission control circuit 10 is controlled based on the access position information. After the data writing process for the transmission frame F is executed, the process returns to step S45.

On the other hand, if the result of determination in step S46 is that the number of times N the transmission frame F has been received is "2", it is determined that this is the second reception of the transmission frame F, and step S4 is performed.
8, the transmission control circuit 10 is controlled based on the access position information to execute the data writing process for the transmission frame F, and then the process proceeds to step S49 to clear the number of receptions N to "0". Then, the process returns to step S43.

Here, as shown in FIG. 6 , the transmission control circuit 10 is connected to the transmission line 1 on the input side and connected to the transmission frame F.
Input side signal line 11 to receive the signal and switch to this signal line 11
The other end is connected to the output side transmission line 1 via the circuit 12.
The output signal line 13 and input signal line 11
Receiving buffer 15 connected via the switching circuit 14
And an output buffer 16 connected to the switching circuit 12.
I am. In addition, the transmission control circuit 10 uses the input side signal line 1
Frame detection circuit 17 connected to 1 and clock extraction
It has a circuit 18. The frame detection circuit 17 has a transmission frame.
Extract the start delimiter part SD located at the beginning of the frame F
However, the extraction of this start delimiter part SD is
For this reason, the start delimiter part SD is given a special code.
Is detected. In addition, the clock extraction circuit 1
8 includes a PLL (face locked loop) circuit
Configured, for example, the start delimiter part of the transmission frame F
A pre-establisher for synchronization establishment that repeats "1" and "0" before SD
When a preamble part is received and a preamble part is provided
Then, the clock pulse CLK synchronized with this is output.

Then, when the frame detection circuit 17 first detects the start delimiter portion SD of the transmission frame F, the frame detection signal FS is sent to the write counter circuit 20.
₁ is output, and when the start delimiter portion SD of the transmission frame F is detected for the second time, the frame detection signal FS ₂ is output to the read counter circuit 19. Further, the clock pulse C of the clock extraction circuit 18
LK is a read counter circuit 19 and a write counter circuit 20.
Is supplied to.

The read counter circuit 19 is the access counter described above.
Number of bytes corresponding to the access position included in the position information
And the data length are preset, and the frame detection circuit 17
It is activated when the frame detection signal FS from
From the transmission frame F by the clock extraction circuit 18.
Count up the extracted clock pulse CLK,
The count value reaches the number of bytes corresponding to the access position
Then, it is assumed that the read start position has arrived and the read switching
No. RS is turned on, and this is applied to the switching circuit 14.
By outputting, this switching circuit 14 turns on.
Status and the necessary data is stored in the receive buffer 15.
Then, the count value reaches the value corresponding to the read data length.
Then, the read switching signal RS is turned off, and the switch
Reading into the reception buffer 15 with the switching circuit 14 turned off
Ends data storage.

Similarly, the write counter circuit 20 is accessed.
The number of bytes corresponding to the access position included in the position information
The data length is preset, and the frame detection circuit 17
These are activated when the frame detection signal FS ₁ is input.
From the transmission frame F by the clock extraction circuit 18.
Count up with the extracted clock pulse CLK,
The count value reaches the number of bytes corresponding to the access position
Then, it is assumed that the write start position has arrived and the write switching
The signal WS is turned on and is output to the switching circuit 12.
As a result, the switching circuit 14 is connected to the output buffer 16 side.
The output buffer 16 is switched in advance and stored in advance.
ON / OFF status data representing the status of the device is output signal line 1
3 and then the count value corresponds to the write data length.
Is reached, the write switching signal WS is turned off and turned off.
The conversion circuit 12 is switched to the input signal line 11 side to write data.
Subsequent data area of the transmission frame, frame
Check sequence unit FCS and end delimiter unit ED
To the output side signal line 13.

Next, the operation of the first embodiment will be described. In this first embodiment, the one selected from a plurality of control device CR ₁ and CR _2, which are connected in a ring network with master controller CR _M, in the master control device CR _M, ring The connection information of the devices connected to the network is collected, the format of the transmission frame F for exchanging data between them is determined, and the access position of the transmission frame F to each device is determined based on the determined format. And after notifying the data length, a transmission frame F in which control data for the output device SOi under its own control is stored in a predetermined data area is generated, and this is transmitted to the downstream output device SO ₁ through the transmission line 1. Send through.

[0033] Upon receiving the transmission frame F by the output device SO _1, since the output device SO is no transmission data _1, only read data, along with no data is stored in the output buffer 16, the first round of When the transmission frame F is received, the frame detection circuit 17 outputs the frame detection signal FS ₁ to the write counter circuit 20, and the write counter circuit 20 is activated to count the clock pulse CLK of the clock extraction circuit 18. However, since the preset value for the access position and the data length is not set in the write counter circuit 20, the write switching signal WS is kept in the off state regardless of the count up. Switching circuit 12
Is maintained in a state where the input side signal line 11 is selected.

Therefore, the transmission frame F input to the input signal line 11 is simply relayed, and is directly transmitted from the output signal line 13 via the switching circuit 12 to the input device SI on the downstream side.
Dispatched to ₁ . In the input device SI _1, for example, only the state data the master controller CR _M assumed to be configured to send, together with the status data is stored in the output buffer 16, the write counter circuit 2
Since the preset values corresponding to the access position and the data length included in the access information are set to 0, when the transmission frame of the first round is received, the input devices SI _{1 and} SI ₁ in the first embodiment described above are received. _{As in the case of 2} , the status data is written in the designated data area of the data portion DT of the transmission frame F, and then the transmission frame F is sent to the control device CR ₂ on the downstream side.

In this control device CR ₂ , the output device SO ₂
Control data need to be transmitted to the write counter circuit 20. The control data is stored in the output buffer 16, and the preset value corresponding to the access position and the data length included in the access information is set in the write counter circuit 20. Therefore, after receiving the first round transmission frame, after writing the control data in the predetermined data area of the data section DT,
The transmission frame F is transmitted to the input device SI ₂ on the downstream side.

Assuming that this input device SI ₂ needs to send status data to the control device CR ₂ ,
Since the state data is stored in the output buffer 16 and the preset value corresponding to the access position and the data length included in the access information is set in the write counter circuit 20, the first round transmission frame is received. At this time, after writing the status data in the predetermined data area of the data portion DT, the transmission frame F is transmitted to the output device SO ₂ on the downstream side.

Since the output device SO ₂ does not have write data like the output device SO ₁ described above, the transmission frame F is simply relayed, and this is transmitted to the master control device CR on the downstream side.
Send to _M. In the master controller CR _M, since receiving the transmission frame F that has one-round, read the status data of the data area to own needs of the data area is written in the data section DT of the transmission frame F After that, the transmission frame F is sent again to the output device SO ₁ on the downstream side.

In this output device SO ₁ , the transmission frame F
Is received, the number of transmissions N becomes “2”, which represents the second round, so that the reading process is executed. The reading process, Ma
Receiving a transmission frame F from the static control device CR _M
Then, the frame detection circuit 17 starts the transmission frame F.
When the delimiter section SD is detected, the read counter circuit 1
9 is activated and the head bit position of the frame control unit FC
The count starts from, but in this state the read counter
In the circuit 19, the data length of the frame controller FC is 1 byte
Your own data length A is set, and you can
Read value is not reached, the read switching signal RS remains off.
Is held, the switching circuit 14 is turned off,
The signal buffer 15 is kept in the disconnected state.

At this time, the write counter circuit 20 is not activated.
This is because the access position and data length are not set.
The write switching signal WS outputted from
The switching circuit 12 switches the state obtained by switching to the input signal line 11 side.
Since the transmission frame F is maintained, the transmission frame F remains unchanged.
13 is sent. In this state, the frame controller FC
When the passage is completed, the reading counter circuit 19
Value reaches the value corresponding to 1 byte of access position
And the read switching signal RS is inverted to the ON state,
The teaching circuit 14 is turned on, which causes the frame
The data written in the next data area DT ₁ of the control unit FC
Control data addressed to itself is received through the switching circuit 14.
Data length A of this control data copied to buffer 15
Bytes were counted up by the read counter circuit 19.
At this point, the read switching signal RS is returned to the off state,
The switching circuit 14 is turned off and the reception buffer 1
Copying of data to 5 is completed.

Therefore, the output device SO ₁ receives
The transmission frame F is sent to the downstream as it is, but it is addressed to itself.
The control data is copied to the reception buffer 15.
After that, the transmission frames F are sequentially transmitted to the input device SI ₁ on the downstream side.
Send to. In this input device SI ₁ , since there is no read data and the preset value is not set in the read counter circuit 19, the control data of the transmission frame F is not copied to the reception buffer 15 and the transmission frame F is relayed. It is sent to the control device CR ₂ on the downstream side via the output signal line 13 as it is.

In this control device CR ₂ , the transmission frame F
In the data area written in the data section DT of the above, the status data required by itself is read based on the access position information, and then the transmission frame F is sent to the input device SI ₂ on the downstream side. Since there is no read data in this input device SI ₂ , the transmission frame F is relayed as it is and sent to the output device SO ₂ on the downstream side, and this output device SO ₂ writes it in the data portion DT of the transmission frame F. after it is loaded with control data Motozuiku data area access position information of there data area, and sends the transmission frame F to the master controller CR _M on the downstream side.

[0042] In the master controller CR _M, since receiving the transmission frame F which has been 2 rounds, after removing the transmission frame F from the ring-shaped network, it generates a new transmission frame F immediately or after a predetermined time has elapsed And sends it to the output device SO ₁ on the downstream side. According to the first embodiment, when a plurality of control devices are connected to the ring network, one control device manages the transmission frame F.
Of the transmission frames F in the first cycle of the control devices CR ₁ , C
Data writing processing is performed by R ₂ and the input devices SI _{1 and} SI ₂ , and each control device CR ₁ ,
Since the CR ₂ and the output devices SO ₁ and SO ₂ perform the data reading process, efficient data transmission can be performed.

Incidentally, when a plurality of control devices sharing the state data of the input device are connected to the ring-shaped network, each of the plurality of control devices has a fixed length as in the first embodiment. When generating a transmission frame and sending it out, the output device or the input device writes all of the write data it has in each transmission frame,
Each control device reads the write data that it needs out of the write data written in the transmission frame, or the output device or the input device predetermines the data to be written for each transmission frame, that is, for each control device. It is possible to divide it and write it in each transmission frame.

However, in the former case, the same data will be written in a plurality of transmission frames, and the same data will flow over the network many times, thus lowering the transmission efficiency. In the latter case, There is an unsolved problem that the processing of the output device and the input device becomes very complicated, but in the present embodiment, these unsolved problems can be solved.

In the first embodiment, the case where the control device is provided with a hardware switch for selecting a master has been described. In the token passing bus system network protocol, when a token disappears from the network,
It is also possible to use a protocol in which each station performs a competition process for token acquisition and finally a station having the largest address acquires a token as a selection protocol of the master control device.

Next, FIGS. 7 to the second embodiment of the present invention
A description will be given together with 10 . The second embodiment was so when a plurality of control devices in a ring network is connected to the first exemplary type condition described above, to reduce the memory capacity of the transmission buffer in the master controller It is a thing. That is, in the second embodiment, as shown in FIG. 7, sequentially output device SO ₁ via the respective transmission path 1 on the downstream side of the master controller CR _M, an input device SI _1, the output unit SO _2, the controller CR _2, and an input device SI ₂ is connected is constructed ring-shaped network, the master controller CR _M and the control device CR ₂ are each input device SI ₁ and state data DI ₁ and DI ₂ of SI ₂ together with read-free, Separate control data is sent to the output devices SO ₁ and SO ₂ .

[0047] Here, after the master controller CR _M is determined as illustrated in FIG. 8 a virtual format of a transmission frame F,
Processing similar to that of the above-described first embodiment except that a transmission frame F in which only its own write data is written in the data portion is generated and is sent to the output device SO ₁ on the downstream side. I do. That is, the format of the transmission frame F, as shown in FIG. 8, the data portion DT is input apparatus SI ₁
And status data DI ₁ of A byte and B byte of SI ₂
And a writing data area DT ₁ and DT ₂ to DI _2, output device SO ₁ and writes the control data DO ₁ and DO ₂ of C bytes and D bytes for SO ₂ data area DT
₃ and DT ₄ .

Here, the data areas DT ₃ and DT ₄ are
C 'byte and D' bytes of master controller CR _M in the second half portion is divided into a respective first half and the second half portion, the remaining bytes of the first half portion is the control device CR ₂ writes people write respectively. Also,
Output devices SO ₁ and SO ₂ and input devices SI ₁ and SI ₂
And the transmission control circuit 10 is configured as shown in FIG.
Has been done. This transmission control device 10 is the same as the first embodiment.
6, in the middle of the input side signal line 11
Is provided with a switching circuit 21 similar to the switching circuit 12.
The transmission frame input to the input signal line 11 by the switching circuit 21.
Whether the data of the system F is directly supplied to the switching circuit 12 side,
If it is supplied to the output buffer 16 of the shift register configuration
And write counter circuit 20 count value
Is greater than or equal to the value corresponding to the access position above the access position
When this happens, the write switching signal WS is maintained in the ON state.
And the write switching signal WS is applied to the switching circuit 12
And 21. The input devices SI ₁ and SI ₂ are configured to add the respective write data to the transmission frame in the first round.

[0049] Further, the control device CR _2, as the transmission control circuit 10 is shown in FIG. 1 0, the number corresponding to the number of output devices write data number or control device CR ₂ itself is the delivery target of the control data Output buffers 16A and 16B, the input side of which is connected to the switching circuit 21 and the output side of which is connected to the switching circuit 12, respectively. Until reaching A + 1 bytes, input side signal line 11
The signal line 22 side directly connecting the output side signal line 13 is set to select the output buffer 16A side when the preset value A + 1 is reached, and the output buffer 16B is selected when the preset value A + C + 1 bytes is reached. ing.

Next, the operation of the second embodiment will be described. Master controller CR _M, first, as shown in FIG. 1 1 (a), the control of the self data portion DT for writing data words output device SO ₁ and SO ₂ data DO ₁ 'and D
A transmission frame F in which only O ₂ ′ is written is generated, stored in the transmission buffer, and then transmitted to the output device SO ₁ on the downstream side via the transmission line 1.

This output device SO₁Then, write data
Therefore, Figure 11As shown in (b), the transmission frame
Relaying the frame F to the downstream input device SI₁Send to
It This input device SI₁Then, there is write data,
Is stored in the output buffer 16, so the frame
After the control section FC has passed, the data is sent in the same way as in the third embodiment.
By inputting the data unit DT to the output buffer 16,
11As shown in (c), after the frame controller FC,
A byte status data DI₁Transmission frame F with
The output device SO on the downstream side.₂Sent to
Output device SO₂Since there is no write data in Fig. 1,1
As shown in (d), the transmission frame F is relayed as it is.
Downstream control device CR₂Send to.

In the control device CR ₂ , after the start delimiter section SD is detected by the frame detection circuit 17, until the write counter circuit 20 reaches the preset value corresponding to A + 1 bytes, the switching circuits 12 and 21 are used. Signal line 22
Since the side is selected, the frame control unit FC of the input transmission frame F and the A byte status data DI1 are directly relayed to the output side signal line 13 via the signal line 22.

After that, when the count value of the write counter circuit 20 reaches the preset value corresponding to A + 1 bytes, the switching circuits 12 and 21 can be switched to the output buffer 16A side, so that the master control following the state data DI ₁ is performed. control data D written in device CR _M C 'bytes
Since O ₁ ′ is supplied to the input side of the output buffer 16A, control data for the output device SO ₁ previously stored in the preceding stage of the control data DO ₁ ′ is added to the output buffer 16A by adding the control data DO _{1 ′.} Is formed, and this is sent to the output side signal line 13 following the state data DI1.

After that, when the control data DO ₁ finishes being sent from the output buffer 16A to the output signal line 13, that is, when the count value of the write counter circuit 20 reaches the preset value corresponding to A + C + 1 bytes, the switching circuits 12 and 2 are provided.
Since 1 is switching換得the output buffer 16B side, control data DO following the _first master controller CR _M in the written D 'bytes of control data DO _2' is the output buffer 16B
This output buffer 16B is supplied to the input side of
Then, control data for the output device SO ₂ stored in advance in the preceding stage of the control data DO ₂ ′ is added to form control data DO ₂ , which is sent to the output side signal line 13 following the control data DO _1. After that, the frame check sequence unit FCS and the end delimiter unit ED are sent to the output side signal line 13, and the transmission frame F shown in FIG. 11 (e) is sent to the downstream side input device SI ₂ .

In this input device SI ₂ , since there is write data, the switching circuits 12 and 21 switch to the output buffer 16 when the count value of the write counter circuit 20 reaches the preset value corresponding to A + 1 bytes. Then, the control data DO ₁ is input to the output buffer 16, the state data DI 2 stored in the output buffer 16 is added to the preceding stage side of the control data DO ₁ and is sent to the output side signal line 13. , Control data DO ₁ , DO ₂ , frame check sequence unit FCS, end delimiter unit ED
There transmission frame F shown in FIG. 1 1 (f) are sent to the output side signal line 13 is sent to the master controller CR _M on the downstream side.

[0056] it is assumed that a transmission frame F sent from the input device SI ₂ obeyed virtual format determined in advance by the master controller CR _M, which is received by the master controller CR _M as a transmission frame F of the second round Once, is the aforementioned second embodiment and the same data reading processing following occurs, the master control device CR _M, output device SO
₁ , SO ₂ and the control device CR ₂ read the data required by each, and then the transmission frame F is transferred to the master control device C.
When received at R _M , this transmission frame F is removed from the network, after which a new transmission frame F is generated and circulated.

According to the second embodiment, when a plurality of control devices are connected to the ring network,
Generating a transmission frame F which it is possible to reduce the data amount of a transmission frame F sent from the master controller CR _M to be sent, the effect is obtained that it is possible to decrease the memory capacity of the transmission buffer. Next, the present invention
The third embodiment with a 1 2 and 1 3 will be described.

[0058] The third embodiment is obtained so as to reduce the data amount of the transmission frame of the second round in the second embodiment. In the third embodiment, FIG. 7
Similarly master controller CR _M and the control device CR _2, ring-shaped network in the output device SO _1, SO ₂ and an input device SI _1, SI ₂ is constructed.

[0059] Then, the format of the transmission frame F by the collection of the connection information in the master controller CR _M are determined, the output device SO _1, SO ₂ and control for reading the data by the cyclic order of the transmission frame F and the format When the device CR ₂ receives the first frame of the transmission frame F and the read data is complete, the read data is read at the same time, and the second frame of the transmission frame F reads the transmission frame F. Delete completed control data.

[0060] Here, deletion of the transmission frame F, master controller CR _M which adds the control data and status data in the data section DT at 1 round of transmission frame F, the control device CR
_2. Input devices SI _{1 and} SI ₂ are used.
The data deletion circuit 30 shown in FIG. In the data deleting circuit 30, the input side signal line 11 is connected to the movable contact t _1a of the switching circuit 31, and one fixed contact t _{1b of the} switching circuit 31 is connected to the output side signal line 13 via the delay buffer 32. The other fixed contact t _1c is connected to the movable contact t _2a of the switching circuit 33, and one fixed contact t of the switching circuit 33 is connected.
_2b is directly connected to the output side signal line 13, and the other fixed contact t _2c is an empty contact.

The switching circuits 31 and 33 output the erase signals DS ₁ and DS ₂ from the erase counter circuit 34.
Is switched by. The erase counter circuit 34
Erase start preset previous self in a transmission frame F of the second round corresponds to the number of bytes representing the final position of the preceding data write data written on the basis of the previously notified access position information from the master controller CR _M When the erasure completion preset value corresponding to the value and the number of bytes representing the final position of the write data written by itself is set, and the frame detection circuit 35 detects the start delimiter part SD of the transmission frame F of the second cycle. When the count value is less than the erase start preset value, the erase signals DS ₁ and DS ₂ are turned off and the count value is erase start preset. If it is more than the value,
The erase signals DS ₁ and DS ₂ are both turned on, and when the count value exceeds the erase completion preset value, the erase signal DS ₂ is returned to the off state.

[0062] The switching circuit 31 and 33, fixed when the fixed contacts t _1b and t _2b when the movable contact t _1a and t _{2 a} is input erase signal DS ₁ and DS ₂ is OFF, is turned on The contacts are switched to t _1c and t _2c , respectively. further,
The delay buffer 32 has its delay amount set to a value according to its own write data length. Here, the switching circuit 31,
33 and the set of the delay buffer 32 must be provided in the number corresponding to the number of data to be erased, the input device SI _1, SI
Since _2, write data is one pair, master controller CR _M and the control device CR _2, write data output device SO _1, since it is two for SO ₂ 2 pairs provided.

Next, the operation of the third embodiment will be described. First, the master controller CR _M, as shown in FIG. 1 1 (a), self-write data words output device SO ₁ and S
'Control data DO ₁ byte' C for O ₂ and D '
Data part D in which only byte control data DO ₂ ′ is written
The transmission frame F having T is generated, stored in the transmission buffer, and then transmitted to the output device SO ₁ on the downstream side.

This output device SO₁Then, write data
Control data DO addressed to self₁′ Exists, so this
Control data DO₁'After reading,1To (b)
As shown, the transmission frame F is directly input to the input device on the downstream side.
SI₁Relay to. This input device SI₁See Figure 11
As shown in (c), in the data part DT of the transmission frame F
Control data DO₁′ 'S status data on the front side
After writing DI1, send the transmission frame F to the downstream output device.
Storage SO₂Send to.

This output device SO₂But the write data
Control data DO addressed to self₂′ Exists, so this
Control data DO₁'After reading',1
As shown in (d), the transmission frame F is directly transmitted to the downstream side.
Control device CR₂Relay to. This controller CR₂Then
The input device SI is used as its own read data.₁Status data
Read it, then output device SO₁as well as
SO₂Control data for each master controller CR_M
Control data DO₁′ And DO₂Write on the front side of '
Control data DO₁And DO₂Figure 1 after configuring1
As shown in (e), the transmission frame F is input to the input device on the downstream side.
SI₂Send to.

[0066] In the input device SI _2, as shown in FIG. 1 1 (f), the master control write the own status data DI ₁ in the preceding stage of the state data DO ₁ 'in the data section DT of a transmission frame F after completing the virtual format determined by the device CR _M, and sends the transmission frame F to the downstream of the master controller CR _M. Upon receiving the transmission frame F of the second round as shown in Fig. 1 3, the master control device CR _M (a), state data DO ₁ and D is a self read data
After reading O ₂ , the transmission frame F is supplied to the data erasing circuit 30.

In the data erasing circuit 30, when the frame detecting circuit 35 detects the start delimiter section SD, the erasing counter circuit 34 is activated to start counting up the clock pulse CLK from the clock extracting circuit 36. At this time, since the count value has not reached the erase start preset value, the erase signals DS ₁ and DS ₂ are both in the OFF state, and the switching circuits 31 and 33 have the fixed contacts t.
_The frame control unit F has been switched to the _1b and t _2b sides.
C, the state data DI ₁ , DI ₂ and the control data DO ₁ ″ written by the control device CR ₂ are supplied to the delay buffer 32, and the delay buffer 32 controls the control data DO ₁ ′ which is its own write data. Is delayed by the delay amount according to the data amount of.

After that, when the count value of the erase counter circuit 34 reaches the erase start preset value, the erase signal DS ₁
And DS ₂ are both turned on, the movable contacts t _1a and t _{2a of} the switching circuits 31 and 33 are switched to the fixed contacts t _1c and t _2c , and the control data written at this time by the self is written. When DO ₁ ′ is erased at the empty contact t _2c , the erase of the control data DO ₁ ′ is completed, and the count value reaches the erase completion preset value, the erase signal DS ₂ is turned off and the switching circuit 33 operates. Since it is returned to the fixed contact t _2b side,
The next control data DO ₂ is transmitted next to the control data DO ₁ ″ delayed by the delay buffer 32.

The transmission frame F from which the control data DO ₁ ′ has been erased is also supplied to the switching circuits 31 and 33 and the delay buffer 32 at the next stage, and this time the control data DO ₂ ′ to the output device DO ₂ is erased. Te, is sent to the output device SI ₁ downstream as a transmission frame F shown in FIG. 1 3 (b). In this output device SI ₁ , the control data DO ₁ ″ written by the control device CR ₂ in the transmission frame F is written.
Since it has not been read, after reading this,
As shown in (c), the transmission frame F is relayed as it is to the input device SI ₁ on the downstream side.

[0070] In the input device SI _1, similarly to the master controller CR _M described above, the transmission frame F indicating the transmission frame F 1 3 clearing the status data DI1 forme self book (d) of the downstream sent to the output device sO _2, and sends the transmission frame F as shown in FIG. 1 3 in the output device sO ₂ (e) directly to the controller CR ₂ downstream relays.

[0071] The transmission frame F shown in Fig. 1 3 erasing the control device CR ₂ even master controller CR _M as well as self two to written control data DO ₁ described above "and DO _2" (f) It is sent to the input device SI ₂ on the downstream side. In the input device SI _2, and transmits the transmission frame F no data unit DT clearing the status data DI2 forme own written as shown in FIG. 1 3 (g) to the master control unit CR _M,
The transmission frame F in the master controller CR _M after removing from the network, generates a new transmission frame F, the downstream side is sent to the output device SO _1.

As described above, according to the third embodiment, the data writing process and the data reading process are performed in the first round of the transmission frame F in the state where the plurality of control devices are connected to the ring network. By doing so, the device that has written the data in the first round in the second round of the transmission frame F can erase the corresponding data, and the data length of the transmission frame in the second round can be shortened accordingly. Therefore, the transmission efficiency can be improved.

[0073] Next, a fourth embodiment of the present invention FIG. 14 for. The fourth embodiment is the same as the third embodiment described above.
Embodiment, the transmission frame F in the first round
The data writing position of the data part DT is fixed at the head position of the data part DT, that is, immediately after the frame control part FC, so that the data insertion / removal process can be easily performed.

[0074] That is, the notification the master controller CR _M, for each input device SI _1, SI ₂ and the controller CR _2, there is no need to notify the writing position information of the data, only the erasure position information of the data To do. Then, each input device SI _1,
In SI ₂ and the control device CR ₂ , the preset value of the write counter circuit 20 of the transmission control circuit 10 is set to a value corresponding to the number of bytes of the common frame control unit FC, and the data erasing circuit 30 treats each erasing target as an individual erasing target. The position of the data is set.

[0075] Thus, for example, as shown in FIG. 14,
The ring-shaped network to write data, for example, the input device SI ₁ ~SI ₃ is assumed to be connected via a transmission line 1, Figure 1 5 in 1 round of transmission frame F, first input device SI ₁ As shown in (a), the state data DI ₁ is additionally inserted at the head position of the data section DT, and then,
Data unit D as an input device SI ₂ shown in FIG. 15 (b)
State data DI ₂ to the beginning of the T is additionally inserted, the state data DI ₃ to the head position of the data portion DT as shown in FIG. 15 (c) is inserted passing further input device SI _3.

Then, in the second round of the transmission frame F, the input
Device SI₁Figure15As shown in (d), the data part DT
Status data DI written by self at the end of₁Erase
Input device SI₂And as shown in FIG.
In the last part of the data part DT,
Data DI₂Is deleted, and the input device SI₃Figure15
As shown in (f), the self at the end of the data part DT
Status data DI written by₃Erase.

As described above, according to the fourth embodiment, in the input device or the control device that writes by adding data to the transmission frame F, the data addition position is fixed at the head position of the common data part. since it is, it is not necessary to notify the data addition position in the master control device CR _M side, it is possible to simplify the notification process, the data to be removed at the end of the data part, from the data unit Since the frame check sequence unit FCS and the end delimiter unit ED on the rear side have no problem in data transmission even if they are discarded, the data can be removed without having to be aware of the information regarding the size of the data to be removed. The effect is obtained.

[0078] Next, a fifth embodiment of the present invention 16 to
FIG. 19 will be described. In the fifth embodiment, in the third and fourth embodiments described above, the distance of the ring network is short, there is almost no delay in the transmission path, and each device relays the transmission frame. If the time required for this is also very short, the beginning part of the transmission frame of the first round will return once after making one round of the network before the transmission of the frame of the first round is completed, and the master control device since it is considered that would cause a collision on the CR _M, is obtained so as to effectively avoid this.

[0079] That is, the master control device CR _M 16
A transmission frame F is generated as shown in (a) (in FIG. 16 , a start delimiter unit SD is provided for convenience of explanation.
Only the control data D I ₁ to omit the additional information of the frame constituting the data portion DT is represented) etc., by sending it to the next input device SI _2, FIG. In the input device SI ₂ 16 (b), the transmission frame is received, and the input device SI ₂ additionally inserts its own state data DI ₂ at the head position of the data section as shown in FIG. 16 (c). Then, this is sent to the input device SI ₃ .

Input device SI ₃ Then figure16Shown in (d)
To receive the transmission frame,As shown in Fig. 16 (e)
ToStatus data DI of its own at the beginning position ₃ Insert additional
And then the nextMaster controller CR _M ThroughInput device SI
₁ To the input device SI ₁ In Fig. 16 (f)
To receive the transmission frame,As shown in FIG. 16 (g)
ToOwn status data DI₁And then send
It At this time,Input device SI ₁ Then figure16(f)
Will receive the transmission frame like16
As shown in (a), the control data DI₁Is being sent
Figure16Send a transmission frame as shown in (f)
Can't do it.

[0081] In the fifth embodiment, the transmission control circuit 10 in the master controller CR _M, as shown in FIG. 17, upon receiving the head of the transmission frame of the first round to the input side signal line 11 A delay buffer 41 having a delay time equal to or longer than the remaining transmission time of the transmission frame F being transmitted by itself is inserted, and the delay buffer 41 and the output buffer 16 are switched to each other.
2 is used to selectively connect to the output side signal line 13, and the frame end detection circuit 43 detects the end delimiter unit ED having a special code at the final position of the transmission frame F sent from the output buffer 16. Switch circuit 4 until
2 is used as the output buffer 16 side to continue the transmission of the transmission frame F, and when the frame end detection circuit 43 detects the end delimiter portion ED of the transmission frame F, the switching circuit 42 is switched to the delay buffer 41 side to delay the delay buffer 41. The transmission frame F which has been delayed for one round and received is received.

[0082] According to the fifth embodiment, by delaying the transmission frame F which has returned to the master controller CR _M to 1 round the ring network by the delay buffer 41, on the master controller CR _M It is possible to surely prevent the collision of the transmission frames, and to smoothly operate the network. Next, a sixth embodiment of the present invention with Figure 18.

[0083] The sixth embodiment, in place of the case where the delay buffer 41 to the master controller CR _M as in the fifth embodiment, to disperse the delay time to a device other than the master controller It was done. In the sixth embodiment, as shown in FIG. 18 , the transmission control circuits 10 of all the devices connected to the network have the frame detection circuit 17 in the configuration of FIG. 9 in the above-described first embodiment. When the second cycle of the transmission frame F is detected, the detection signal FS ₂ is turned on, and the detection signal FS ₂
Is input to one input side of the OR gate 50, the write signal WR of the write counter circuit 20 is input to the other input side of the OR gate 50, and the output of the OR gate 50 is switched.
The configuration is the same as that of FIG. 9 except that it is supplied to Nos. 2 and 21, and the portions corresponding to those of FIG. 9 are denoted by the same reference numerals and detailed description thereof will be omitted.

In the sixth embodiment, when the second round transmission frame having the longest data amount is received, this is detected by the frame detection circuit 17, and the frame detection signal FS2 is turned on. Since it is supplied to the switching circuits 12 and 21 via the OR gate 50, the received transmission frame F is set to the output buffer 16 by being sent to the output side signal line 13 via the output buffer 16 of the shift register configuration. As a result, the data length of the write data of the first round is delayed, and this delay time is added by each device. Therefore, the transmission data length of all devices connected to the network as a whole network. It can give rise to minute delay, even when the network is short, to ensure a collision of a transmission frame in the master control device CR _M-proof You can stop.

Next, a description will be given of a seventh embodiment of the present invention with Figure 19. The seventh embodiment is the same as the third embodiment described above.
In the above embodiment, it is possible to easily perform the data removal processing and also to prevent the collision of the transmission frames. In the seventh embodiment, FIG. 19
As shown, the master control device CR _M, an input device S
I ₁ and the input device SI ₂ are connected via the transmission line 1 to form a ring network.

[0086] Then, the master control device CR _M and the input device SI _1, a self-write data or control data DO and status data DI ₁ to the last part of the data portion in one round of the SI ₂ transmission frame F, DI ₂ Is set in advance so that the self-write data existing at the head position of the data section DT in the second round of the transmission frame F is deleted.

[0087] According to the seventh embodiment, first, as shown in FIG. 2 0 (a) in the master control device CR _M, generates a transmission frame F to writing the control data DO in the data portion DT, which To the input device SI ₁ on the downstream side. In the input device SI _1, as shown in FIG. 2 0 (b), by adding inserts status data DI ₁ is a self-write data to the end portion of the data portion DT in the transmission frame F, the downstream input Send to device SI ₂ .

[0088] In this input device SI _2, as shown in FIG. 2 0 (c), by adding inserts status data DI ₂ is a self-write data to the end portion of the data portion DT in the transmission frame F, downstream To the device on the side. When the transmission frame F shown in FIG. 2 0 by one round the network (d) is received by the master controller CR _M, written self at the head position of the data portion DT at the master controller CR _M The control data DO is erased, and the downstream input device SI ₁
It sent to erases the status data DI ₁ by itself written at the beginning of the data portion DT when receiving the transmission frame F shown in FIG. 2 0 (e) In this input device SI _1, the downstream sent to the input device SI _2, the input device SI ₂ any 2 0 self at the beginning of the data portion DT when receiving the transmission frame F shown in (f) is written status data DI
Delete ₂ and send to downstream equipment.

[0089] Therefore, an apparatus for erasing itself written data, it is sufficient erase its own write data that erasing of data to the head position of the data unit, the data erase position from the master controller CR _M Without having to notify
The access position information can be simplified. Further, since the erasing head data of the data portion, as described above, when the data DO was sent started as shown in FIG. 2 1 (a) in the master control device CR _M, each input device to the data DO Status data DI ₁ and DI with SI ₁ and SI _2
2 is added into the rearmost position (FIG. 2 1 (b) ~ (e )
See), which has become the network by one-round back to the master control unit CR _M reference (FIG. 2 1 (f)), the data is removed provided the master controller CR in _M the input signal line 11 since the control data DO is self write data is erased by the circuit 30, after the data erasing is completed, as shown in FIG. 2 1 (g), the input device and the remaining state data DI ₁ and DI ₂ Send to SI ₁ .

[0090] As a result, it is possible to reliably prevent the transmission frame F in the master control device CR _M collides,
Similarly, since the input devices SI ₁ and SI ₂ also erase their own write data at the head position of the data section DT from the received transmission frame, it is possible to reliably prevent the collision of the transmission frame. In the third to seventh embodiments described above, the transmission frame F transmitted from the device that lastly performed the data processing has the following relationship because the data erasing processing is performed in the second round of the transmission frame F. as shown in FIG. 2 0 (g), a start delimiter portion SD, a frame control unit F
C, since only becomes additional information does not include the data portion DT comprising a frame check sequence portion FCS and end delimiter portion ED, but which are to be removed by the master controller CR _M, the invention is not limited thereto no, it is also possible to remove the next transmission frame additional information upon reception of after sending the transmission frame F of the second round with any device on the downstream side of the master controller CR _M. In this case, in order to determine the device for removing the additional information, by turning on the removal selection switch provided in advance in each device,
May also be determined to, it may be reported from the master controller CR _M at the time of initial setting.

[0091] Further, when erasing data in the last part of the data portion DT as in the fourth embodiment there is the distance from the master controller CR _M until the data to be removed from the head of the transmission frame The erased data position is notified,
In the last device for erasing data on the network, the value of the erase data position information becomes equal to the sum of the data lengths of the start delimiter unit SD and the frame control unit FC, which is a fixed length. when it is notified of the erasing data location information from the master controller CR _M, when the value is the sum equal unit data length of the start delimiter SD, and the frame control unit FC receives the transmission frame to the second round, Instead of deleting the data in the data part, the entire transmission frame may be removed.

In each of the above embodiments, the case where the data arrangement order of the data portion DT in the transmission frame F is the connection order of each station has been described. Alternatively, they may be arranged collectively for each station type, that is, for each output device SO and input device SI, and an arbitrary arrangement order can be set.

In each of the above embodiments, the case where the number of devices forming the network is small has been described for simplification of the description. However, the present invention is not limited to this, and any number of devices may be connected to the network. You can

[0094]

As described in the foregoing, according to the signal transmission method in the ring network according to 請 Motomeko 1, a ring-shaped network constituted by a plurality of control devices and a plurality of input and output devices, a plurality One of the control devices
One master control device, and this master control device circulates a fixed-length transmission frame, so that each input device and output device and the remaining control device perform data transfer in the first cycle for this transmission frame. And write the data in the second cycle.
Data is read in, so when multiple control units are connected , multiple control units can individually transmit a transmission frame.
Output device and input device
It is possible to obtain an effect that the transmission efficiency can be remarkably improved without complicated processing .

[0095] Also, according to the signal transmission method in the ring network according to claim 2, to determine one of multiple control devices as a master controller, the master controller is a variable-length transmission frame since the power sale by is circulated, reduce the memory capacity of the transmission buffer in the control unit
It is possible to obtain the effect that the transmission efficiency can be further improved when a plurality of control devices are connected.

Further, according to the signal transmission method in the ring network according to the third aspect , in addition to the invention of the second aspect , when the device to which the data is added next receives the transmission frame, its own additional data is added. Is eliminated, the effect is obtained that the cyclic transmission frame length can be shortened and the transmission efficiency can be further improved. According to the signal transmission method in the ring network of claim 4 , in addition to the invention of claim 3 , when data is added, the data is added to the head position of the data part of the transmission frame and erased. At this time, the last data of the data part is erased, so that it is possible to easily add and remove the data.

Further, according to the signal transmission method in the ring network according to the fifth aspect , in addition to the invention of the fourth aspect , when data is added, it is added to the last position of the data part of the transmission frame. When deleting this, the data at the beginning position of the data part is deleted, so
It is possible to easily perform the addition and removal processing of data and to reliably prevent the collision of the transmission frame in the master control device or the like.

Further, according to the signal transmission method in the ring network according to claim 6 , claims 2 to 5 are provided.
In the invention, since the master control device removes the transmission frame that has completed the circulation, it is possible to reduce the amount of circulation of the unnecessary transmission frame and surely remove the transmission frame. Still further, according to the signal transmission method in the ring network according to the seventh aspect , since the transmission frame is removed by the device that finally removes the additional data from the transmission frame, the number of unnecessary transmission frame cycles is minimized. As a result, the effect that it can be reliably removed is obtained.

[0099] Also, according to the signal transmission method in the ring network according to claim 8, since the delay means for delaying the transmission frame received in any of the devices connected in a ring network is provided, Even if the ring-shaped network is short and the relay time between the devices is short, and the head of the transmission loops back to the master control device while making a round of the network during transmission of the transmission frame by the master control device. The effect that it is possible to reliably prevent the collision of

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing a first embodiment of the present invention.

FIG. 2 is a flowchart showing an example of a transmission processing procedure of the control device in the first embodiment.

FIG. 3 is an explanatory diagram of network connection information collection processing according to the first embodiment.

FIG. 4 is a diagram showing a format of a transmission frame set by a control device.

FIG. 5 is a flowchart showing an example of a transmission processing procedure of a control device, an output device, and an input device other than the master control device according to the first embodiment.

FIG. 6 is a block diagram showing an example of a transmission control circuit of the output device and the input device according to the first embodiment.

FIG. 7 is a schematic configuration diagram showing a second embodiment of the present invention.

FIG. 8 shows a transmission frame structure in the second embodiment.
FIG .

FIG. 9 is a transmission control circuit of the control device according to the second embodiment.
It is a block diagram which shows an example of a path .

FIG. 10 is a block diagram showing an example of a transmission control circuit of an output device and an input device according to the second embodiment.

FIG. 11 is a diagram showing changes in transmission frame according to the second embodiment .
FIG .

FIG. 12 is data deletion according to the third embodiment of the present invention .
It is a block diagram showing an example of a circuit .

FIG. 13 is a diagram showing changes in the transmission frame in the third embodiment .
It is an explanatory view showing a.

FIG. 14 is a schematic configuration diagram showing a fourth embodiment of the present invention .

FIG. 15 shows a change in transmission frame according to the fourth embodiment .
It is an explanatory view showing a.

[16] Transmission of a transmission frame in the fifth embodiment
It is explanatory drawing which shows a state .

17 is a block diagram showing an example of a heat transmission control circuit that put to a fifth embodiment.

FIG. 18 is an example of a transmission control circuit according to a sixth embodiment.
It is a block diagram showing .

FIG. 19 is a schematic configuration diagram showing a sixth embodiment .

FIG. 20 is an explanatory diagram showing a change of a transmission frame in the seventh embodiment.

FIG. 21 is a diagram illustrating transmission of a transmission frame according to the seventh embodiment .
It is explanatory drawing which shows a state .

[Explanation of symbols]

T transmission line CR control device SI ₁ , SI ₂ input device SO ₁ , SO ₂ output device 10 transmission control circuit 11 input side signal line 12 switching circuit 13 output side signal line 14 switching circuit 15 reception buffer 16 output buffer 17 frame detection circuit 18 clock extraction circuit 19 reading the counter circuit 20 the write counter circuit CR _1, CR ₂ controller CR _M master controller 21 switching circuit 16A, 16B output buffer 30 the data erase circuit 31, 33 a switching circuit 32 the delay buffer 34 erases the counter circuit 35 Frame detection circuit 36 Clock extraction circuit 41 Delay buffer 42 Switching circuit 43 Frame end detection circuit 50 OR gate

Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) H04L 12/42

Claims (8)

(57) [Claims] 1. A plurality of output devices for outputting a control signal to a control device, a plurality of input devices for inputting a control status signal of the control device, and each control based on a control status signal from the input device. A plurality of control devices that send control data to the output device while monitoring the state of the equipment are connected to a ring network to perform signal transmission between each control device and each output device and input device. In the signal transmission method in the ring-shaped network,
Connection information that includes a master selection unit that selects only one master control unit from the plurality of control units, and the control unit selected by the master selection unit collects connection information of each device connected to the ring network. Collecting means; format determining means for deciding a format of a transmission frame for exchanging data between each control device and each output device and input device based on the connection information collected by the connection information collecting device; Data access position indicating means for indicating an individual data access position on the transmission frame when the transmission frame is received to each output device, the input device and the control device based on the format determined by the format determining means; A transmission frame is generated according to the format determined by the format determining means, and this is used as a ring network. When the frame transmitting means for transmitting to the work and the frame transmitted by the frame transmitting means are received, it is judged whether or not it is the second round, and if it is the first round, the frame is circulated as it is and the second round. And a frame removing unit that removes the transmission frame from the ring-shaped network after taking in the necessary data in the transmission frame, and the device other than the master control device receives the transmission frame when the transmission frame is first received. Writing data to the data access position designated by the data access position designating means of the master control device and fetching data at the data access position designated by the data access position designating means when the data is received in the second cycle. Characteristic signal transmission method in ring network. 2. A plurality of output devices for outputting a control signal to a control device, a plurality of input devices for inputting a control state signal of the control device, and each control based on a control state signal from the input device. A plurality of control devices that send control data to the output device while monitoring the state of the equipment are connected to a ring network to perform signal transmission between each control device and each output device and input device. In the signal transmission method in the ring-shaped network,
Connection information that includes a master selection unit that selects only one master control unit from the plurality of control units, and the control unit selected by the master selection unit collects connection information of each device connected to the ring network. Collecting means, and a virtual format deciding means for deciding a virtual format of a transmission frame for exchanging data between each control device and each output device and input device based on the connection information collected by the connection information collecting device. A data access position instruction for instructing an individual data access position on the transmission frame when the transmission frame is received to each output device, input device and control device based on the virtual format determined by the virtual format determination means Means and each output device according to the virtual format determined by the virtual format determination means. To generate a transmission frame in which the control data to be written is transmitted, and to transmit the transmission frame to the ring network, and when the frame transmitted by the frame transmission means is received, it is determined whether or not it is the second cycle. However, the control device other than the master control device is provided with a data capturing means for retrieving the frame as it is during the first round, and for capturing the necessary data in the transmission frame during the second round. When the first transmission frame is received, data is added to the data access position designated by the data access position designating means of the master control device, and when the second frame is received, the data access position designating means is similarly designated. The data at the selected data access position is fetched, and each of the input devices receives the data from the master control device when the transmission frame is first received. Data access position indicating means writes data to a designated data access position from the respective output device, a transmission frame 2
The control data of the data access position designated by the data access position designating means of the master control device when the data is received in the second round is taken in, and the transmission frame of the third round is transmitted to any device connected to the ring network. A signal transmission method in a ring-shaped network, characterized in that a frame removing means for removing the signal from the ring-shaped network is provided. 3. A control device including the master control device and an output device add data to a data access position according to a virtual format determined by the virtual format determination means when first circulating a transmission frame, Two
3. The signal transmission method in the ring network according to claim 2, wherein when the transmission frame is circulated in the round, the data added by itself is deleted and circulated. 4. The control device including the master control device and the input device add write data to the beginning of the data portion of the transmission frame when first circulating the transmission frame, and
3. The signal transmission method in the ring network according to claim 2, wherein when the transmission frame is circulated in the round, the data added by itself is deleted and circulated. 5. The control device including the master control device and the input device add write data to the end of the data portion of the transmission frame when first circulating the transmission frame, and
3. The signal transmission method in the ring network according to claim 2, wherein when the transmission frame is circulated in the round, the data added by itself is deleted and circulated. Wherein said frame removing means, the signal transmission method in the ring network according to any one of claims 2 to 5, characterized in that provided in the master controller. 7. The frame removing means is provided in a device that deletes additional data at the end among a control device and an input device other than a master control device, according to any one of claims 3 to 5. Signal transmission method in the ring network described. 8. A delay means for delaying a received frame is inserted in at least one data receiving side of an output device, an input device and a control device connected to a ring network. 8. A signal transmission method in the ring network according to any one of 1 to 7 .