JPH0771099B2 - Token passing data communication terminal device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a data communication system, and in particular, a plurality of terminal devices are connected to a common loop-shaped transmission line, and transmission rights are transmitted between the terminal devices. That is, the present invention relates to a terminal device of a data communication system by a so-called token passing system, which communicates by passing a free token.

(Prior Art) Conventionally, three types of systems have been proposed as a token passing communication algorithm, that is, a signal processing procedure. See, for example, Nikkei Electronics, March 14, 1983, "Local Network for Penetrating Sites through Buses and Rings," pages 163-166. One is a single token method in which a node sends a free token when the head of a transmission frame returns, and the other is a single packet method in which a node collects all transmission frames and then sends a free token. Finally, it is a multi-token system in which a node sends a transmission frame and then immediately sends a free token. The name of each of these methods is based on "Performance Evaluation of Token Ring Network Considering Priority" by IEICE Technical Report, Volume 83, No. 190, SE-128 by Yamamoto et al.

(Problems to be Solved by the Invention) In the conventional token passing data communication system, it is fixedly determined which of these three algorithms is to be applied to each system. Therefore, each node device included in the system is configured with hardware so as to fixedly implement an algorithm according to the system. That is, each of these three methods has been realized by a node device having a dedicated hardware configuration.

In such a conventional situation, a node device of a certain communication algorithm system cannot be directly applied to a token ring of another system. From the manufacturer side that supplies node devices, this is because node devices with different hardware configurations are prepared according to the three types of token ring systems.
It had to be provided, making the equipment supply inefficient. Also, the node device used in one system could not be diverted to another system due to some circumstances.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above drawbacks of the prior art and to provide a terminal device of a token passing data communication system that can be commonly applied to any communication algorithm system token ring system.

(Means for Solving Problems) In order to solve the above-mentioned problems, the present invention connects a plurality of terminal devices to a loop-shaped common transmission line, and the terminal devices acquire a transmission right to transmit a transmission frame. A terminal device of the token passing data communication system that transmits data in a format is connected to a common transmission line and receives a transmission frame and a transmission right, and is connected to the common transmission line and responds to the received transmission right and a transmission request. Then, transmitting means for transmitting to the transmission frame common transmission path according to a predetermined signal processing procedure for the common transmission path, and monitoring means connected to the receiving means and monitoring the return of the transmission frame sent by the transmission means from the common transmission path. And the transmission means includes a storage means capable of programming the signal processing procedure, and a common transmission path of the transmission frame according to the programmed signal processing procedure. To send to.

(Operation) According to the present invention, the signal processing procedure according to the signal processing procedure method of the common transmission line, for example, the single token method, the single packet method, or the multi-token method is set in the storage means. For example, in the single token system, the transmitting means executes the transmission in accordance with the signal processing procedure of the storing means so that the monitoring means detects the return of the head portion of the transmission frame and then transmits the transmission right.
Further, in the single packet method, the transmitting means executes the transmission in accordance with the signal processing procedure of the storing means so that the monitoring means detects the return of the end portion of the transmission frame and then transmits the transmission right. Similarly, in the multi-token method, as soon as the transmission of the transmission frame ends, the transmission right is transmitted,
The transmission means executes the transmission according to the signal processing procedure of the storage means.

(Embodiment) Next, an embodiment of a token passing data communication system according to the present invention will be described in detail with reference to the accompanying drawings.

For example, as shown in FIG. 2A, in a specific embodiment of the token passing data communication system according to the present invention, a plurality of node devices, that is, terminal devices 10 are connected to a loop-shaped common transmission line, that is, loop 5. . Node device 10
In the copper embodiment, are arranged at four positions A to D, and the host machine is connected thereto.

The transmission right, that is, the free token 6, is transmitted to the ring 5 prior to the transmission frame 7. The transmission frame 7 is
As shown in FIG. 6, a header H, which indicates the beginning of the frame 7,
This is followed by a destination address DA indicating the address of the destination node or terminal device, a source address SA indicating the address of the source node or terminal device, data D to be transmitted thereafter, and finally an end indicating the end of the transmission frame 7. It is composed of field E.

As shown in FIG. 1, the node device 10 arranged in each of the nodes A to D basically has a frame / transmission right reception control unit.
104, a transmission control unit 110, a return frame reception control unit 113, a memory 118, and their related circuits are connected as shown in the figure.

The common transmission line 5 is connected to the shift register 101, and the shift register 101 converts a serial signal into a parallel signal.
This is temporarily stored in the register 102, and the selector (SEL
1) At 103, the frame / transmission right reception control unit 104 or the return frame reception control unit 113 transfers the frame. The switching control is controlled by the SEL1 control unit 115.

The frame / transmission right reception control unit 104 responds to the frame 7 or the free token 6 received from the transmission path 5 and the transmission request.
It is a functional unit that controls the LEL1 control unit 115 and the transmission control unit 110, and its output line 126 has a second selector (SEL2) 106 and a reception FIFO (first-in first-out memory).
It is connected to 116.

The transmission control unit 110 is a functional unit that forms an important part of the present invention, and controls the reception of the free token 6 and the transmission of the transmission frame 7 of the free token 6 based on the transmission request 132.
The transmission control unit 110 has a control program unit 202, which is
The storage device stores a control program that implements a communication algorithm of the loop or token ring 5 to which the node device 10 is applied, that is, a signal processing procedure. The control program unit 202 is, for example, a read-only storage device (RO
M) or a programmable storage device such as a programmable logic array (PLA).

In this specification, the term “memory device” is to be broadly interpreted to include not only a normal memory device such as a ROM but also a circuit programmable to a desired logic sequence, such as a PLA. Similarly, the term “programmable” is to be construed to include not only the state in which program steps can be stored but also the case where the input / output correspondence can be set as desired.

The transmission control unit 110 includes a flip-flop 201 that latches the output of the control program unit 202, a selector (SEL3) 203 that selects the state transition number (SEQNO) of the control program, and a transmission right transmission circuit 121 that transmits the free token 6. Are connected and configured as follows.

The return frame reception control unit 113 is a functional unit that monitors the return of the transmitted frame 7 from the loop 5, and includes a frame end field detection circuit 128 that detects the frame end field E, and the head portion of the received frame 7, for example, its An SA coincidence detection circuit 127 for detecting the coincidence of the transmission address SA with its own node address is connected and configured as shown.

The free token 6 and the transmission frame 7 to be transmitted to the common transmission path 107 are transferred from the selector (SEL2) 106 to the shift register 107. The selector 106 is a selection circuit that selects which of the free token 6 and the transmission frame 7 is transmitted, and the selection is controlled by the SEL2 control unit 112. The shift register 107 is a circuit whose output side is connected to the common transmission line 5 and which converts parallel data into serial data and sends the serial data to the transmission line 5.

The transmission data D is stored in the memory 118. The memory 118 is
Receive FIFO 116 and Transmit FIFO 10 via Memory Bus 117
Connected to 8. Receive FIFO 116 and Transmit FIFO 108
Is a memory that adjusts the difference in data transfer rate between the common transmission path 5 and the memory bus 117. The data received from the transmission path 5 is received by the reception FIFO 116, and the data to be transmitted to this is transmitted by the transmission FIFO 108. Is temporarily stored in.

The node device 10 is connected to the overall control unit of the host machine that controls the overall communication operation, and executes control by the storage program method. However, this functional part is not shown in order to avoid complication of the drawing and description.

By the way, when the node device 10 is applied to a multi-token node, the input / output logic shown in FIGS. 3 and 2 is set in the control program unit 202. Figure 3.1 shows the operation sequence for the multi-token method. In the figures after FIG. 3.1, the numbers in the circles correspond to the above-mentioned state transition number SEQNO.

In the multi-token system, the free token 6 is transmitted immediately after the transmission frame 7 is transmitted. The signal processing procedure in the node device 10 is as follows. First, the processing of the free token 6 in each of the nodes A to D when the free token 6 is circulating in the loop 5 as shown in FIG. 2A will be described. When the free token 6 arrives at the node A from the ring 5 in the form of a serial signal, the node device
This is received by 10 shift registers 101 and converted into parallel signals. This is held in the register 102.

The selector 103 is set to select the connection point b side in the normal state. Therefore, the free token 6 converted into the parallel signal is input to the frame / transmission right reception control unit 104. The frame / transmission right reception control unit 104 determines whether it is the free token 6 or the frame 7 that is received from the transmission path 5.

When the reception of the free token 6 is detected, it is determined whether or not there is a transmission request 132 from the overall control unit. When the transmission request 132 is not issued, the received free token 6 is transmitted from the frame / transmission right reception control unit 104 to the signal line 105.
Is sent to the input a of the selector 106 via. Selector 106
Is set to select the connection point a side in the normal state. Therefore, this free token 6 is directly output to the shift register 107, directly converted into a signal, and then the loop 5
Sent to. Such a processing procedure is executed by the node device 10 of each of the nodes A to D.

As shown in FIG. 2B, a case where node A receives a free token 6 (FIG. 2A), acquires a transmission right, and tries to transmit data will be described. When the free token 6 arrives at the node device 10 of the node A from the loop 5, this is converted into a parallel signal by the shift register 101 and held in the register 102. Since the selector 103 is set to select the connection point b side in the normal state,
The free token 6 is transferred to the frame / transmission right reception control unit 104. The control unit 104 determines whether the signal received at this time is the header H of the frame 7 or the free token 6. When the reception of free token 6 is detected,
It is determined whether or not there is a transmission request 132 from the overall control unit. When there is a transmission request 132, the frame / transmission right reception control unit 104 converts this into the header H of the frame 7 and sends it to the input a of the selector 106 via the signal line 105. Since the connection point a side is selected in the selector 106 in the normal state, the header H is guided to the shift register 107, converted into a serial signal, and sent to the loop 5.

Simultaneously with the exchange of the free token 6 for the header H in the frame / transmission right reception control unit 104, the frame / transmission right reception control unit 104 activates the transmission control unit 110 through the control line 109. After the header H sent out via the signal line 105 passes through the selector 106, the transmission control unit 110 activates the SEL2 control unit 112 via the signal line 130. This allows SEL2 control unit 1
Reference numeral 12 switches the connection point of the selector 106 from a side to b side. Therefore, the transmission controller 110 sends the data D from the transmission FIFO 108.
To start sending data. Transmission control unit 110
Is header H, followed by incoming address DA and outgoing address
The transmission frame 7 is assembled and transmitted by adding the SA and the end field E.

When the transmission control unit 110 is activated by the activation of the control line 109 of the frame / transmission right reception control unit 104, the SEL1 control unit 115 is also activated. In response to this, the control unit 115 makes the connection point of the selector 103 from the b side. Switch to side a. As a result, the return frame reception control unit 113 causes the register 10 via the selector 103.
The return of the frame 7 which is connected to 2 and circulates in the loop 5 is monitored.

The operation of the transmission control unit 110 in the multi-token system will be described in detail with reference to the operation flow of FIG. In the normal state, the state transition number output SEQNO of the control program unit 202 of the transmission control unit 110 is the state of the fourth item in the input / output logic table of FIG. 3.2, that is, binary “11”, that is, decimal “3”. Is set to. That is, the flow of FIG. 3.1 (c) is repeated. In the following input / output logic table, "*" indicates a "don, t care" bit.

When transmitting the frame 7, the selector 203 of the transmission control unit 110
The connection point a side was selected as the normal state until then, but the frame / transmission right reception control unit 104 controls the control line 1
When 09 is activated, it is switched to the connection point b side for a predetermined period. Since the binary number "00" is fixedly input to the connection point b side, the state transition number input SEQNO of the control program section 202 from the selector 203 is set to "00".

At this time, the transmission request 132 is turned on, that is, the transmission request signal S
Since RDY is "1" (300), control program section 202
Takes the state of the first item in the input / output logic table in Figure 3.2. That is, the state transition number output SEQNO of the control program unit 202 is binary "00", and the signal S-OUT is "1", that is, turned on (302). Therefore, the flip-flop 201 is set to this state, and in response to the signal S-OUT, the SEL2 control unit 1
Reference numeral 12 switches the connection point of the selector 106 from a side to b side. Therefore, the transmission control unit 110 takes out the data D from the transmission FIFO 108 and transmits the data. This state transition "0"
Continues until the transmission request signal SRDY turns off, and the transmission control unit 110 continues transmitting data. That is, Fig. 3.1 (a)
Repeat the flow of.

When the frame end field E is transmitted from the transmission FIFO 108 (FIG. 2 (b)), the transmission request signal SRDY is turned off by the overall control unit. The control program section 202 assumes the state of the second item in the input / output logic table of FIG. That is, the state transition number output SEQNO of the control program unit 210 is 2
It will be a "01" of Susumu. Since the connection state of the selector 203 has returned to the state of selecting the connection point a side, the state transition number output SEQNO “01” is fed back to the same input SEQNO of the control program unit 202 via the selector 203. Therefore, the control program unit 202 shifts to the state of the third item in the same input / output logic table (Fig. 3.2), and the signal T-SEND becomes "1", that is, turned on (304). Therefore, the flip-flop 201 is set to this state, and in response to the signal T-SEND, the transmission right control unit 121 starts transmitting the free token 6 and S
The EL2 control unit 112 switches the connection point of the selector 106 to the c side. Then, the free token 6 is transmitted from the transmission right transmission circuit 121 to the loop 5 via the selector 106.

After sending the free token 6, the connection point of the selector 106 returns to the a side. When transitioning to the transition state “3”, the transmission control unit
110 is the first to continue this "idle state" as described above.
Figure 3.1 (c)). As a result, a multi-token system is realized in which the free token 7 is sent out immediately after the transmission of the frame 7 is completed.

The transmitted frame 7 goes around the loop 5 and returns to the transmitting node A again (FIGS. 2B to 2D). At this time, since the connection point of the selector 103 is selected to the side a, the return frame reception control unit 113 discards the returned frame 7. The frame end detection circuit 128 of the control unit 113 continues until the end field E of the received frame 7 is detected.
When the discard is completed until the end of the same frame 7, the control edge 129 is activated. In response to this, the SEL1 control unit 115 switches the selector 103 to the connection point b side. As a result, the node device 10 returns to the normal frame and free token reception state.

When the node device 10 is applied to a single token type node, the input / output logic shown in FIG. 4.2 is set in the control program unit 202. The operation sequence is shown in Figure 4.1. The free token 6 arrived from the loop 5 is acquired in the node device 10 of the node A by the same procedure as in the case of the multi-token. This is converted into the header H of the frame 7 by the frame / transmission right reception control unit 104,
It is sent to the selector 106 via the signal line 105. Selector 10
Since the connection point a side of 6 is selected in the normal state, the header H is guided to the shift register 107, converted into a serial signal, and sent to the loop 5.

At the same time as the conversion of the free token 6 into the header H in the frame / transmission right reception control unit 104, the frame / transmission right reception control unit 104 activates the transmission control unit 110 through the control line 109. After the header H sent out via the signal line 105 passes through the selector 106, the transmission control unit 110 activates the SEL2 control unit 112 via the signal line 130. This allows SEL2 control unit 1
Reference numeral 12 switches the connection point of the selector 106 from a side to b side. Therefore, the transmission control unit 110 takes out the data D from the transmission FIFO 108 and starts data transmission. Transmission control unit 11
In 0, the header H is followed by the incoming address DA, the outgoing address SA, and the end field E to assemble the transmission frame 7 and transmit it.

When the transmission control unit 110 is activated by the activation of the control line 109 of the frame / transmission right reception control unit 104, the SEL1 control unit 115 is also activated. In response to this, the control unit 115 makes the connection point of the selector 103 from the b side. Switch to side a. As a result, the return frame reception control unit 113 causes the register 10 via the selector 103.
The return of the frame 7 which is connected to 2 and circulates in the loop 5 is monitored.

The operation of the transmission control unit 110 in the case of the single token method will be described in detail with reference to the operation flow of FIG. In the normal state, the state transition number output SEQNO of the control program section 202 of the communication control section 110 is the fifth in the input / output logic table of FIG.
The state of the term, ie binary "11", ie decimal "3"
Is set to. That is, the flow of FIG. 4.1 (c) is repeated.

When transmitting the frame 7, the selector 203 of the transmission control unit 110
The connection point a side was selected as the normal state until then, but the frame / transmission right reception control unit 104 controls the control line 1
When 09 is activated, it is switched to the connection point b side for a predetermined period. Since the binary number "00" is fixedly input to the connection point b side, the state transition number input SEQNO of the control program section 202 from the selector 203 is set to "00".

At this time, the transmission request 132 is turned on, that is, the transmission request signal S
Since RDY is "1" (300), control program section 202
Takes the state of the first item in the input / output logic table in Fig. 4.2. That is, the state transition number output S of the control program 210
EQNO is binary "00", and the signal S-OUT is "1", that is, turned on (302). Therefore, the flip-flop 201 is set to this state, and the SEL2 control unit 112 responds to the signal S-OUT.
Switches the connection point of the selector 106 from the side a to the side b.
Therefore, the transmission control unit 110 takes out the data D from the transmission FIFO 108 and transmits the data. This state transition "0" is
It continues until the transmission request signal SRDY turns off, and the transmission control unit 11
0 Continue sending data. That is, the flow of FIG. 4.1 (a) is repeated.

When the frame end field E is transmitted from the transmission FIFO 108, the transmission request signal SRDY is turned off by the overall control unit. The control program unit 202 assumes the state of the second item in the input / output logic table of FIG. That is, the state transition number output SEQNO of the control program section 210 is binary "01".
Since the connection state of the selector 203 has returned to the state of selecting the connection point a side, the state transition number output SEQNO “01” is transmitted to the same input SEQN of the control program unit 202 via the selector 203.
Returned to O.

The return frame reception control unit 113 monitors the return of the transmission frame 7. The SA coincidence detection circuit 127 monitors the reception of the transmission address SA of frame 7. Sending address SA
Since the control output line SAF is not activated unless is received, the input transition state number SEQ to the control program unit 201 SEQ
NO keeps "01", that is, the state of the fourth item of the input / output logic table (Fig. 4.1 (b)).

The SA match detection circuit 127 circulates in the loop 5 and returns from the beginning of the frame 7, that is, the transmission address in this case.
When SA is detected, the circuit 127 turns on the signal line SAF, that is, sets it to "1" (310). Therefore, the control program unit 202 shifts to the state of the third term in the same input / output logic table (Fig. 4.2), and the signal T-SEND is "1", that is, turned on (312). Therefore, the flip-flop 201 is set to this state, and in response to the signal T-SEND, the transmission right control unit 121 starts transmitting the free token 6, and the SEL2 control unit 112 sets the connection point of the selector 106 to the c side. Switch. Therefore, the free token 6 is sent from the transmission right transmission circuit 121 to the selector 1
Sent on Loop 5 via 06.

After sending the free token 6, the connection point of the selector 106 returns to the a side. When transitioning to the transition state “3, the transmission control unit 11
0 continues this "idle state" as described above (No.
4.1 (c)). As a result, the single token method in which the free token 7 is sent out after receiving the head portion of the frame 7 is realized.

The transmitted frame 7 goes back through the loop 5 and returns to the transmitting node A again, but since the connection point of the selector 103 is selected to the side a, the return frame reception control unit 113 discards the returned frame 7. . The frame end detection circuit 128 of the control unit 113 activates the control line 129 when the discard of the received frame 7 until the end is completed. In response to this, the SEL1 control unit 115 switches the selector 103 to the connection point b side. As a result, the node device 10 returns to the normal frame and free token reception state.

By the way, when the node device 10 is applied to a single packet type node, the input / output logic shown in FIG. 5.2 is set in the control program unit 202. The operation sequence is
Shown in Figure 5.1. The free token 6 arrived from the loop 5 is acquired in the node device 10 of the node A by the same procedure as in the case of the multi-token. This is a frame
The transmission right reception control unit 104 converts the header H of the frame 7 and sends it to the selector 106 via the signal line 105. Since the connection point a side is selected in the selector 106 in the normal state, the header H is guided to the shift register 107, converted into a serial signal, and sent to the loop 5.

Simultaneously with the exchange of the free token 6 for the header H in the frame / transmission right reception control unit 104, the frame / transmission right reception control unit 104 activates the transmission control unit 110 through the control line 109. After the header H sent out via the signal line 105 passes through the selector 106, the transmission control unit 110 activates the SEL2 control unit 112 via the signal line 130. This allows SEL2 control unit 1
Reference numeral 12 switches the connection point of the selector 106 from a side to b side. Therefore, the transmission control unit 110 takes out the data D from the transmission FIFO 108 and starts data transmission. Transmission control unit 11
When 0 is added to the header H, the incoming address DA, the outgoing address SA and the end field E are added, and the transmission frame 7 is assembled and transmitted.

When the transmission control unit 110 is activated by the activation of the control line 109 of the frame / transmission right reception control unit 104, the SEL1 control unit 115 is also activated. In response to this, the control unit 115 makes the connection point of the selector 103 from the b side. Switch to side a. As a result, the return frame reception control unit 113 causes the register 10 via the selector 103.
The return of the frame 7 which is connected to 2 and circulates in the loop 5 is monitored.

The operation of the transmission control unit 110 in the case of the single packet method will be described in detail with reference to the operation flow of FIG. In the normal state, the state transition number output SEQNO of the control program unit 202 of the transmission control unit 110 is the 5th state in the input / output logic table of FIG.
The state of the term, ie binary "11", ie decimal "3"
Is set to. That is, the flow of FIG. 5.1 (c) is repeated.

When transmitting the frame 7, the selector 203 of the transmission control unit 110
The connection point a side was selected as the normal state until then, but the frame / transmission right reception control unit 104 controls the control line 1
When 09 is activated, it is switched to the connection point b side for a predetermined period. Since the binary number "00" is fixedly input to the connection point b side, the state transition number input SEQNO of the control program section 202 from the selector 203 is set to "00".

At this time, the transmission request 132 is turned on, that is, the transmission request signal S
Since RDY is "1" (300), control program section 202
Takes the state of the first item in the input / output logic table in Figure 5.2. That is, the state transition number output SEQNO of the control program section 210 is binary "00", and the signal S-OUT is "1", that is, turned on (302). Therefore, the flip-flop 201 is set to this state, and in response to the signal S-OUT, the SEL2 control unit 1
Reference numeral 12 switches the connection point of the selector 106 from a side to b side. Therefore, the transmission control unit 110 takes out the data D from the transmission FIFO 108 and transmits the data. This state transition "0"
Continues until the transmission request signal SRDY turns off, and the transmission control unit 110 continues transmitting data. That is, Figure 5.1 (a)
Repeat the flow of.

When the frame end field E is transmitted from the transmission SFIFO 108, the transmission request signal SRDY is turned off by the overall control unit. The control program unit 202 takes the state of the second item in the input / output logic table of FIG. That is, the state transition number output SEQNO of the control program section 210 is binary "01". Since the connection state of the selector 203 has returned to the state of selecting the connection point a side, the state transition number output SEQNO “0
1 ”is fed back to the same input SEQNO of the control program section 202 via the selector 203.

The return frame reception control unit 113 monitors the return of the transmission frame 7. The end-of-frame field detection circuit 12
8 is monitoring the reception of the end field E of frame 7. Since the control output line 129, that is, the signal R-END is not activated unless the end field E is received, the input transition state number SEQNO to the control program section 201 is "01",
That is, the state of the fourth item of the input / output logic table is kept (the fourth item).
5.1 (b)).

When the frame end field detection circuit 128 detects the frame 7 end field E which has returned after circulating through the loop 5, the circuit 128 turns on the signal line R-END, that is, "1".
(320). Therefore, the control program unit 202 shifts to the state of the third item in the same input / output logical table (see 5.2.
In the figure, the signal T-SEND is "1", that is, turned on (32
2). Therefore, the flip-flop 201 is set to this state, and in response to the signal T-SEND, the transmission right control unit 121 starts transmitting the free token 6 and the SEL2 control unit 11
2 switches the connection point of the selector 106 to the c side. Then, the free token 6 is transmitted from the transmission right transmission circuit 121 to the loop 5 via the selector 106.

After sending the free token 6, the connection point of the selector 106 returns to the a side. When transitioning to the transition state “3”, the transmission control unit
110 is the first to continue this "idle state" as described above.
5.1 (c)). This realizes the single packet method in which the free token 7 is transmitted after receiving the end field E of the frame 7.

The received frame 7 goes back through the loop 5 and returns to the transmitting node A again, but since the connection point of the selector 103 is selected to the side a, the return frame reception control unit 113 discards the returned frame 7. . The frame end detection circuit 128 of the control unit 113 activates the control line 129 when the discard of the received frame 7 is completed. In response to this, the SEL1 control unit 115 switches the selector 103 to the connection point b side. As a result, the node device 10 returns to the normal frame and free token reception state.

As described above, according to the present invention, the programmable storage device is used for the frame transmission function part of the terminal device, and the content of the algorithm is set according to the token ring signal processing procedure system. It is possible to provide a common hardware terminal device regardless of the signal processing procedure system. In other words, it can be commonly applied to any communication algorithm type token ring system.

[Brief description of drawings]

FIG. 1 is a functional block diagram showing an embodiment of a node device for realizing the token passing data communication system according to the present invention, and FIG. 2 is an explanatory diagram for explaining the token passing data communication system according to the present invention, FIG. 3.1, FIGS. 4.1 and 5.1 are operation flow diagrams of the transmission control unit of the same node device in the multi-token system, the single token system and the sigle packet system, respectively, in FIG. 3.2, FIG. 4.2, FIG. 4.2 and FIG. FIG. 6 is a diagram showing an input / output logical table set in the control program unit of the same node device in the multi-token system, the single-token system and the single-packet system in the present embodiment, respectively. FIG. 6 is a transmission frame used in the embodiment. It is a figure which shows the example of a format of. Explanation of code of main part 5 …… Common transmission line 7 …… Transmission frame 104 …… Frame / transmission right reception control unit 110 …… Transmission control unit 113 …… Return frame reception control unit 201 …… Flip-flop 202 …… Control Program section 203 …… Selector

Claims (3)

[Claims] 1. A terminal device of a token passing data communication system, wherein a plurality of terminal devices are connected to a common loop transmission line, and the terminal device obtains a transmission right to transmit data in a transmission frame format. The device is connected to the common transmission path, receives a transmission frame and a transmission right, and is connected to the reception means and the common transmission path and responds to the transmission right and the transmission request received by the reception means. And transmitting means for transmitting a transmission frame to the common transmission path in accordance with a predetermined signal processing procedure corresponding to the token ring signal processing procedure method for the common transmission path, and connected to the receiving means, and sent by the transmission means. Monitoring means for monitoring the return of the transmission frame from the common transmission path, wherein the transmitting means is a storage device capable of programming the signal processing procedure. And a step of setting the signal processing procedure in the storage unit according to the signal processing procedure method of the token ring, and transmitting a transmission frame to the common transmission path based on the set signal processing procedure. A terminal device of a token passing data communication system characterized by: 2. The apparatus according to claim 1, wherein the monitoring unit includes a detection unit that detects a leading portion and an ending portion of the received transmission frame, and the storage unit includes the common transmission path. A logic array capable of programming the logic of a signal processing procedure specific to the transmitting means, the transmitting means includes a holding means for holding a transmission request and a current state in the signal processing procedure, and the transmitting means includes the programmable logic. According to a signal processing procedure according to the token ring signal processing procedure system programmed in the array, the logical state of the predetermined signal processing procedure is operated in response to the detection means and the holding means, and the signal is transmitted according to the operation result. By controlling the state transition of the frame transmission, the transmission frame according to the signal processing procedure according to the signal processing procedure method of the token ring. A terminal device characterized by transmitting a frame. 3. The apparatus according to claim 1, wherein the monitoring unit includes a detection unit that detects a head portion and an end portion of the received transmission frame, and the storage unit includes the common transmission path. A read-only storage device for storing the logic of a signal processing procedure specific to the above, the transmission means includes a holding means for holding a transmission request and a current state in the signal processing procedure, and the transmission means includes the read-only storage. In accordance with a signal processing procedure according to a token ring signal processing method stored in the device, a logical state of the predetermined signal processing procedure is calculated in response to the detection means and the holding means, and a transmission frame is calculated according to the calculation result. By controlling the state transition of the transmission of the transmission frame, the transmission frame is transmitted according to the signal processing procedure corresponding to the signal processing procedure of the token ring. And a terminal device.