JPH0720118B2 - Data transmission / reception method using multiple loops - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of use) The present invention relates to a slotted ring data communication system having a plurality of loops, in which data distributed to each node and transmitted to its own node is transmitted by a transmission source. The present invention relates to a method of receiving data without breaking the order.

(Prior Art) When constructing a large-capacity communication system by the slotted ring method, a multi-loop configuration may be considered in order to suppress an increase in loop speed as shown in FIG. 1 (C). At that time, if each time slot of multiple loops is treated as a time slot of one loop logically,
Multiple loops can be efficiently used with various data without using a complicated loop selection algorithm. In that case, each node on the transmitting side sequentially sends out the information from the own node to the vacant time slots of the loop which are logically one. That is, information is sent across multiple loops. On the receiving side, it is necessary to store the data distributed to each node and transmitted to its own node in the buffer memory without breaking the order of the data at the transmission source and to output to the terminal or the output line. To this end, it is necessary to know the number of times each of the time slots addressed to the own node, which arrives simultaneously from the plurality of loops, is transmitted from the transmission node. For this reason, conventionally, a counter for each transmitting node was installed in common for multiple loops,
Each loop is monitored in turn every 1 timeslot time,
The counter counts the number of time slots addressed to the own node for each transmission, and the count value determines the write address of the received data in the buffer memory.

A conventional method will be described with reference to FIGS. 2 (a) and 2 (b). The conventional data communication method using multiple loops is
A loop configuration as shown in FIG. 1 (c) is adopted, and the receiving unit of each node is configured as shown in FIG. 2 (a). Second
The receiving unit in FIG. 5A analyzes the data from the loop and takes in the data addressed to the own node, and the data reception signal sent from the data analysis unit 30 and indicating that the data addressed to the own node has been taken in. A group of counters 10 for counting the number of frames from the beginning of the frame for each transmitting node, a buffer memory 20 provided for each transmitting node corresponding to each loop, and storing received data based on the address calculated by the counter, and receiving The data output unit 40 outputs the output data to the outgoing line.

The data from a certain node to its own node is sent by treating a plurality of loops logically as one loop as shown in FIG. 2 (b). For example, the first data in the first slot of loop 1, the second data in the first slot of loop 3, the third data in the second slot of loop 4, the third slot of loop 2, etc. For the 4th slot, loop 1 for the 4th slot, the 5th data for the 4th slot, loop 4
The 6th data is sent to the 4th slot. As shown in FIG. 1 (d), the data of each time slot is sent with an address (SA, DA) indicating the transmitting node and the receiving node. In the receiving node, the data analysis unit 30 looks at the DA of the data on the loop and takes in the data addressed to the own node into the node. Further, the SA of the data and the data reception number are sent to the counter group 10 provided for each SA. The counter group 10 sequentially monitors all loops within one time slot, and counts how many time slots are addressed to its own node through all loops for each SA from the frame head. In other words, in the counter group 10, if data comes from a certain loop in a certain time slot, the counter value corresponding to the SA of the data is incremented by one, and that value is used as an address for the buffer corresponding to each SA. The data is written in the memory 20. This operation is sequentially performed for all loops within one time slot time. Then, as shown in FIG. 2A, for example, the node A corresponding to each loop is
In the buffer memory 20 for data, data is written in respective positions corresponding to the order sent from the node A. For example,
Assuming that the data is transmitted from the node A as shown in FIG. 2 (b), if the initial value of the counter for node A in the counter group 10 is set to 0, the counter for transmitting node A in loop 1 in the first slot Is incremented by 1 and data is written to the position of address 1 of loop 1. In loop 3, the counter for node A is further incremented by 1, and data is written in the address 2 position of loop 3. As described above, the data 1 to data 6 are written in the addresses 1 to 6 corresponding to the transmission order of the data in the memory corresponding to the loop to which they are respectively sent. Although only one transmission address has been described above, the above operations are similarly performed in parallel for the other transmission addresses by the counter and the buffer memory corresponding to the addresses. As can be seen from FIG. 2 (a), since the data is written in the buffer memory corresponding to the loop at random,
All empty areas of the buffer memory are set to 0 in advance, and when outputting data to the output line, the same address is given to the buffer memories of all loops, and the outputs of the buffer memories of all loops are ORed and output. If the above-mentioned functions are given to the data output section 40, the data is output to the outgoing line in the order of being sent from the transmitting node, as shown in FIG.

(Problems of Prior Art) In the conventional data transmission / reception system described above, since the buffer memory is provided for each loop, it is sufficient to operate at the speed of one loop, but the counter is common to all nodes. All loops must be monitored within one time slot time, and when data destined for the own node arrives at once from all loops, the counter must operate at the number of loops times the loop speed. However, since the data of many lines are collected on the loop, the speed of the loop is much higher than the speed of each line, and it is difficult to realize a counter that can withstand the speed when many loops are installed. Yes, the operating speed of the counter limited the transmission capacity of all loops.

(Object of the Invention) An object of the present invention is to determine the operating speed of the entire device that outputs received data to an outgoing line in the order in which they are sent from a transmitting node,
Even when there are multiple loops, it is necessary to reduce the speed below the speed corresponding to the loop.

(Structure of the Invention) The present invention, when multiple loops are logically regarded as one loop to transmit and receive data, so that all parts of the data transmitting and receiving device can operate at a speed corresponding to the loop or less,
In the conventional high-speed section, instead of the counter that generated the storage address of the data from the loop at a speed corresponding to multiple loops, the order of the data is recognized at the place where the data from each loop is output to the output line. Then, a low-speed selector that selects data from the reception buffer memory corresponding to each loop and outputs it to the outgoing line is placed, and the data is transmitted and received. That is, the present invention connects a plurality of nodes by a plurality of loops, provides a frame of a constant time period on each loop, divides the frame into a plurality of time slots, synchronizes the frames of all loops, the phases of the time slots, Each node transmits data to be transmitted by using any free time slot on the plurality of loops, in a data transmission / reception method using a plurality of loops in a slotted link type data communication system for communicating between nodes, For each loop, each node is provided with a reception time slot number counter and a reception buffer memory installed for each partner node, and each node is provided with a selector for selecting data to be output from the reception buffer memory to the outgoing line. Each node divides the data to be transmitted in time slot units, and The data is assigned a sending node number and a receiving node number, and the information to be sent from its own node is sent to the empty time slots of each loop according to the order of the loop, and each node flows on the loop. The reception time slot number counter installed in each partner node corresponding to the loop counts the data addressed to the own node sent from the partner node through the loop, and the reception time slot number The value of the counter is used as an address and the data and the time slot number to which the data is sent are stored in the reception buffer memory corresponding to the partner node. Further, each node stores the address of the reception buffer memory for each partner node. In this order, the received data is stored in the receive buffer memory of each loop corresponding to the target node. The time slot number stored together with the data is read out, and if there is a plurality of data corresponding to the smallest time slot number among the time slot numbers or a plurality of data corresponding to the smallest time slot number, Among them, the data transmission / reception method using a plurality of loops is characterized in that the data of the loop having the highest predetermined priority is determined, the data is read from the reception buffer memory, and is output to the outgoing line.

(Operation / Principle of the Present Invention) As described above, in the data transmission / reception method using a plurality of loops, data is transmitted over the plurality of loops. Therefore, when data arrives from a plurality of loops at the same time in the same time slot, the node receiving the data must output the data sent from the partner node to the outgoing line without breaking the order. Therefore, in the present invention, the time slot number on the loop where the data is received is stored together with the data. Then, the order of data is managed on the outgoing line side, which is generally slower than the loop side, to avoid high speed operation. That is,
If there are many timeslot numbers with the same timeslot number that was stored with the data,
By outputting the data sent from the loop having a higher predetermined order, the data sent from the partner node is output to the outgoing line without breaking the order.

Embodiments Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 (a), (b), (c) and (d) are schematic diagrams showing one embodiment of a data transmission / reception system using a plurality of loops of the present invention. The data transmission / reception method using a plurality of loops according to this embodiment has a function of sending data to a plurality of data transmission lines 120 and a plurality of data transmission lines 120 as shown in FIG.
Data transmission line 1 that forms a loop by connecting the nodes 110 and 130 that have the function of receiving data from the
It consists of 20. Further, the receiving units of the nodes 110 and 130 are configured as shown in FIG. In other words, it is provided for each loop and DA, SA
And a data analysis unit 140 that outputs the data addressed to its own node to the reception buffer memory 160 for each SA, and a counter 150 that is provided for each loop and SA for sequentially reading and writing the reception buffer memory 160 from the beginning. Also, a receiving buffer memory 160, which is also provided for loop and SA support, temporarily stores the received data for outputting to the output line, and at the same time, stores the time slot number to which the data has been transmitted, and the output line. When data is output to the terminal, when there is the smallest data of the time slot number or the large number of data of the smallest time slot number, the selector 170 is configured to sequentially output the data from the loop having a predetermined higher order to the output line.

In addition, in FIG. 1 (a), a counter 150 corresponding to a certain SA,
Only the buffer memory 160 is shown. The counter 150 and the buffer memory 160 corresponding to other SAs are connected to the data analysis unit 140 like the counter 150 and the buffer memory 160 shown in FIG.

Next, the operation of the data transmission / reception method using a plurality of loops of this embodiment will be described with reference to FIGS. 1 (a), (b), and (c). As shown in FIG. 1 (b), it is assumed that the data is divided into 6 time slots and sent from the node 110 to the node 130 as data 1 to data 6 by using the slotted ring method. As shown in Fig. 1 (d), each data has D
A and SA are added. At this time, the data is sent in the order of data 1 to data 6 by regarding the plurality of data transmission paths 120 as one logically as in the conventional example. The transmitted data sequentially enters the node 130 from the frame head. In the node 130, the data analysis unit 140 installed corresponding to each loop analyzes SA and DA of the data coming from the loop, and if the DA indicates the node 130, the data is converted into the S
Output to the buffer memory 160 corresponding to A. When data is output from the data analysis unit 140 in the buffer memory 160, the data and the time slot number to which the data is sent are written to the address indicated by the value of the counter 150 corresponding to the buffer memory 160, and the counter 150 Advances the value of by one. Since all of these operations are performed independently in each loop, the operation of the counter 150 may be performed at a loop-compatible operation speed. As described above, all the data transmitted to the node 130 in one frame is divided for each SA, and as shown in FIG. It is written in the buffer memory 160. Further, the data in the buffer memory 160 are all given the time slot number to which the data was sent. Next, in order to output the data stored in the buffer memory 160 to the outgoing line, it is necessary to output the data sent from the node without breaking the order. by the way,
When sending data from a node to a plurality of data transmission paths 120, since the data transmission paths are logically regarded as one and the data is sent, the data must always have the same time slot number and be the same. In the time slot, the time slots of the loop with the highest rank are listed first. Therefore, even in the data in the buffer memory 160 provided for the loop, the order relation sent from the nodes is maintained. Therefore, the selector 170 selects from the data having the smallest time slot number to which the data is sent among the data having the value of the counter 150 in the buffer memory 160 provided for each loop as an address and the youngest time slot. If the data sent by is present in many loops, the loops with the highest priority will be output in order. Also, every time data is output to the outgoing line, the counter 150 is incremented by 1 corresponding to the loop, the time slot number corresponding to the next data is read out, and then it can be compared with other time slot numbers.

For example, as shown in FIG. 1 (b), data 1 to data 6
Is sent to the relevant node, data 1 to data 6 are stored in the order in which the data was sent from the beginning of the address, as described in the buffer memory 160 in FIG. 1 (a). It When outputting the data 1 to 6 to the outgoing line, first, the counter 150 of all loops is reset. Then, the address indicated by the counter 150, that is, the time slot number of the data stored in the address 0 of the reception buffer memory 160 of all the loops is compared. Then, it can be seen that there is data sent in the earliest time slot 1 in loop 1 and loop 3. In this case, since there are two pieces of data sent in the same time slot, the data of loop 1 having a higher rank is output to the outgoing line first, and the counter 150 of loop 1 is incremented by one. In order to determine the data to be output next, the same comparison operation is performed, and the data sent in the earliest time slot is the data 2 of loop 3, so this is output to the output line and the loop is output. The value of the counter 150 of 3 is incremented by 1. By repeating the above operation, data 1 to data 6 are sequentially output to the outgoing line as shown in the output of FIG.

Note that the function of outputting the data of the loop with the highest rank when a large number of data are sent with the same time slot number can be realized by inserting a priority encoder or the like in the data selector 170. The operation speed of the data selector 170 described above may be a speed matching the output speed of the outgoing line, because the speed of the outgoing line is slower than the speed of the loop in which data from many lines are flowing.

(Effects of the Invention) As described above, according to the present invention, high-speed data arriving simultaneously from a plurality of loops is temporarily stored in the loop-capable reception buffer memory 160, and the low-speed outgoing line selector 170 is stored.
By determining the order of the data with and outputting to the outgoing line, the selector 170 can be operated at a speed corresponding to the low-speed outgoing line, and the buffer memory 160 and the counter 150 can also be operated at the speed corresponding to the loop. , It is possible to exclude high-speed operation units that operate corresponding to multiple loops from the entire node.

[Brief description of drawings]

FIGS. 1 (a), (b), (c) and (d) are schematic diagrams of one embodiment of a data transmission / reception system using a plurality of loops of the present invention,
2A and 2B are schematic diagrams showing a conventional data transmission / reception method using a plurality of loops.

Claims (1)

[Claims] 1. A plurality of nodes are connected by a plurality of loops,
A frame with a constant time period is provided on each loop, the frame is divided into a plurality of time slots, the frames of all the loops and the phases of the time slots are synchronized, and each node transmits data to be transmitted on the plurality of loops arbitrarily. In a data transmission / reception method using multiple loops in a slotted drink type data communication system in which communication is performed between nodes by transmitting using the empty time slots of A reception time slot number counter and a reception buffer memory are further provided, and each node is provided with a selector for selecting data to be output from the reception buffer memory to the outgoing line. Each node divides the data to be transmitted into time slot units. Then, add the sending node number and the receiving node number to the divided data, Information that should be sent from the self node is sent to the empty time slot of the loop according to the order of the loop, and each node takes in the data addressed to the self node that is flowing on the loop, and is set for each partner node in response to the loop. The received time slot number counter counts the data addressed to its own node sent from the partner node through the loop, and uses the value of the received time slot counter as an address to send the data and the time when the data was sent. The slot number is stored in the reception buffer memory corresponding to the partner node, and each node has the reception buffer memory of each loop corresponding to the partner node in the order of the address of the reception buffer memory for each partner node. The time slot number stored together with the received data in the If there is a plurality of data corresponding to the smallest one among the timeslot numbers, or a plurality of data corresponding to the smallest timeslot number, the predetermined priority is the highest among the data. A data transmission / reception method using a plurality of loops, wherein data of a loop is determined, the data is read from the reception buffer memory, and is output to an outgoing line.