JPH0693690B2 - Loop type data transmission system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention is used in a loop data transmission system for data communication. In particular, the present invention relates to a 1: 1 and 1: N communication method in which data is transmitted using only a specific frame when loop transmission delay correction is performed in frame units instead of multiframe units in a data transmission path that constitutes a multiframe.

〔Overview〕

According to the present invention, in a loop data transmission system, in the case of a multi-frame structure, a channel frame number having a number equal to the frame number other than the frame number of each frame is added to the frame data and inserted, and added to this frame data. By branching the frame data based on the channel frame number, the data slave stations before and after the loop master station can acquire the channel at the same frame timing, and perform 1: N communication using a predetermined frame number. It was made possible.

[Conventional technology]

Conventionally, the loop type data transmission line has a single frame structure. The loop master station synchronizes the received data with the frame, inputs the received data to the loop transmission delay correction circuit, temporarily accumulates the data, and outputs the data at independent frame timings.
The data master station inputs / outputs the transmission / reception data of the master terminal which carries out frame synchronization with the received data and constantly adds / drops the data. The data slave station synchronizes the received data with the frame to make the data branched and accommodated as the received data of the slave terminal, and inserts the transmitted data based on the transmission request from the slave terminal.

[Problems to be solved by the invention]

However, in such a conventional loop-type data transmission method, the frame configuration is changed from a single frame configuration to a multi-frame configuration, and the loop transmission delay correction of the loop master station is performed in the conventional frame unit to prevent the transmission delay time from increasing. If you leave it as it is, if you transmit data using some frames in the multi-frame, when the data passes through the loop master station, it is output at the next frame timing by the loop transmission delay correction circuit, and the data is output to different frames. There is a drawback that only the data transmission in which all the frames are continuously used can be performed because the transfer becomes impossible and the communication becomes impossible.

The present invention solves the above-mentioned drawbacks, and data slave stations before and after a loop master station can acquire a channel at the same frame timing and perform 1-to-N communication using a predetermined frame number. An object is to provide a loop type data transmission system.

[Means for solving problems]

According to the present invention, in the loop type data transmission system, the branching / inserting means of the data master station adds a channel frame number having a number equal to the frame number to the frame data and inserts the frame number from the received data. It is characterized in that it includes means for branching the frame data to which the number is added, and the branching and inserting means of the data slave station includes means for inserting and dropping the frame data to which the corresponding frame number for the channel is added.

[Action]

The branching / inserting means of the data master station adds the channel frame number of the same number as the frame number to the inserted frame data and inserts it, and branches the frame data to which the corresponding channel frame number is added from the received data. The branching / inserting means of the data slave station inserts the frame data with the corresponding channel frame number added, and drops the frame data with this number added from the received data. By the above operation, the data slave stations before and after the loop master station can acquire the channel at the same frame timing,
One-to-N communication can be performed using a predetermined frame number.

〔Example〕

Embodiments of the present invention will be described with reference to the drawings. First
FIG. 1 is a block diagram of a loop type data transmission device according to an embodiment of the present invention. FIG. 3 is a block diagram of a loop master station of the loop type data transmission device of the present invention. FIG. 4 is a block diagram of a data master station of the loop data transmission device of the present invention. FIG. 5 is a block diagram of a data slave station of the loop type data transmission apparatus of the present invention. Figures 1 and 3
In FIG. 4, FIG. 4 and FIG. 5, the loop-type data transmission device includes one loop master station 1 and one data master station 3.
A plurality of data slave stations 2a, 2b, 2c, a loop type data transmission line connecting the above stations in a loop, a master terminal 4 connected to the data master station 3, and data slave stations 2a to 2c And the slave terminals 5c, 5a, 5b
A frame synchronization circuit 6a, a loop transmission delay correction circuit 7, a master clock generation circuit 8, a multiframe generation circuit 9 and a multiplex circuit 10 as loop transmission delay correction means for temporarily accumulating received data and transmitting at the next multiframe timing.
, The data master station 3 and the data slave station 2,
Frame synchronization circuits 6b, 6c and data add / drop insertion circuits 11a, 11b as means for relaying frame data in synchronization with the multiframe timing, and means 12a, 12b for adding / dropping corresponding frame data in the multiframe, terminal data Separation circuits 13a and 13b and terminal data multiplexing circuit 15
Includes a and 15b.

The feature of the present invention is that the branching / inserting means of the data master station 3 adds a channel frame number having a number equal to the frame number to the frame data and inserts it.
A channel frame synchronization circuit 12a and a channel frame generation circuit 1 are provided as means for branching the frame data to which the corresponding channel frame number is added from the received data.
The means for inserting and dropping the data slave stations 2a, 2b, 2c including 4 is a channel frame synchronizing circuit 12b and a channel frame number transmitting circuit as a means for inserting and dropping the frame data to which the corresponding channel frame number is added. 1
It is to include 6.

The operation of the loop-type data transmission device having such a configuration will be described.

FIG. 2 is a time chart of signals of each part of the loop type transmission line of the present invention. In FIGS. 1 and 2, the data master station 3 uses the frame number 1 (F1) in the multiframe.
The transmission data from the master terminal 4 accommodated in synchronization with the frame No. 1 is inserted into the loop type data transmission line as frame data A (# 1) to which the frame number # 1 for the same channel as frame number 1 (F1) is added, The data slave station 2b relays the received data and branches to the slave terminal 5a accommodating the frame data A (# 1) in synchronization with the channel frame number # 1. Similarly to the data slave station 2b, the data slave station 2c relays the received data and also transmits the frame data A (#
It branches to the slave terminal 5b accommodating 1).

Further, since the loop master station 1 temporarily stores the received data and transmits it at the next frame timing, the frame data A (#
1) is transmitted as data of frame number 2 (F2).
Further, the data slave station 2a relays the received data in the same manner as the data slave station 2b, and at the same time, synchronizes with the frame of the channel frame number # 1 to obtain the frame data A (# 1) from the frame of frame number 2 (F2). In addition, the loop-shaped data is branched as frame data B (# 1) of the channel frame number # 1 in synchronization with the transmission data based on the transmission request from the accommodating slave terminal 5c. Inserted in the transmission line, the data master station 3
In synchronization with the channel frame number # 1, it branches to the master terminal 4 that accommodates the frame data B (# 1).

In FIG. 3, the loop master station 1 determines the synchronization of the received data by the frame synchronization circuit 6a, inputs the received data to the loop transmission delay correction circuit 7 in frame units, and operates with the output clock signal of the master clock generation circuit 8. The loop transmission delay correction circuit 7 outputs the reception data at the frame timing of the multi-frame generation circuit 9, and the multiplexing circuit 10 adds the frame number output from the multi-frame generation circuit 9 to the reception data and transmits the data.

In FIG. 4, the data master station 3 is a data add / drop circuit.
The reception data branched at 11a is subjected to synchronization determination by the channel frame synchronization circuit 12a, and the timing of the corresponding frame data output from the terminal data separation circuit 13a to the master terminal 4 is controlled. The terminal data multiplexing circuit 15a outputs from the master terminal 4 the channel frame number output from the channel frame generation circuit 14 which operates at the control timing of the frame synchronization circuit 6b which determines the frame synchronization of the reception data of the loop type data transmission line. The data is added to the transmission data, and the frame data is inserted from the data add / drop circuit 11a at the timing of the frame synchronization circuit 6b.

In FIG. 5, the data slave station 2a is a data add / drop circuit.
The reception data branched at 11b is subjected to synchronization determination by the channel frame synchronization circuit 12b, and the timing of the corresponding frame data output from the terminal data branch circuit 13b to the slave terminal 5c is controlled. The terminal data multiplexing circuit 15b uses the channel frame synchronization circuit 12 based on the transmission request from the frame terminal 5c.
Add the channel frame number output from the channel frame number transmission circuit 16 operating at the control timing of b to the transmission data from the slave terminal 5c, and insert the frame data from the data add / drop insertion circuit 11b at the timing of the frame synchronization circuit 6c. To do.

〔The invention's effect〕

As described above, according to the present invention, the data slave stations before and after the loop master station can acquire the channel at the same frame timing and can freely perform the 1: N communication using the predetermined frame number. There is an excellent effect that the band can be efficiently divided according to the terminal data rate.

[Brief description of drawings]

FIG. 1 is a block diagram of a loop type data transmission device according to an embodiment of the present invention. FIG. 2 is a signal time chart of each part of the loop type data transmission device of the present invention. FIG. 3 is a block diagram of a loop master station of the loop type data transmission device of the present invention. FIG. 4 is a block configuration diagram of a data master station of the loop type data transmission apparatus of the present invention. FIG. 5 is a block configuration diagram of a data slave station of the loop type data transmission apparatus of the present invention. 1 ... Loop master station, 2a-2c ... Data slave station, 3 ... Data master station, 4 ... Master terminal, 5a-5c ... Slave terminal,
6a to 6c ... Frame synchronization circuit, 7 ... Loop transmission delay correction circuit, 8 ... Master clock generation circuit, 9 ... Multi-frame generation circuit, 10 ... Multiplex circuit, 11a, 11b ... Data add / drop circuit, 12a, 12b ... channel frame synchronization circuit, 13a, 13b ... terminal data separation circuit, 14 ... channel frame generation circuit, 15a, 15b ... terminal data multiplexing circuit, 16 ... channel frame number transmission circuit.

Claims (1)

[Claims] 1. A loop master station comprising: one loop master station; one data master station; a plurality of data slave stations; and a loop type data transmission line connecting the stations in a loop. , A loop transmission delay correction means for temporarily accumulating received data and transmitting at the next multi-frame timing, wherein the data master station and the data slave station respectively relay frame data in synchronization with the multi-frame timing. In the loop data transmission method including a unit for adding and dropping the corresponding frame data in the multiframe, the unit for adding and dropping the data master station adds a channel frame number equal to the frame number to the frame data. Including a means for branching the frame data to which the frame number for the corresponding channel is added from the received data. Means for branching and inserting the data slave station, a loop-shaped data transmission system which comprises means for inserting branches frame data corresponding channel frame number appended.