JPS6225524A - Frame multiplex transfer system - Google Patents

Abstract

PURPOSE:To improve the utilizing efficiency of a line by starting the frame transmission from a frame transmission start time slot assigned fixedly at each allocated line and sending data while monopolizing the succeeding time slot until the end of transmission. CONSTITUTION:A frame received from a line 2 is transferred and stored into a buffer memory 5 by a DMA circuit 3. Each time slot on a line 7 is assigned as the time slot starting the transmission of the frame received from the line corresponding to each allocated line 2, a multiplexing/distribution circuit 6 checks the presence of a frame in the state of transmission standby at each transmission time slot of a line 7, and when the frame exists, the succeeding time slot is used continuously and all the signals are sent. The similar operation is repeated after the end of transmission of one frame. Thus, the utilizing effi ciency of the multiplex line is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention provides a method for receiving frames 'f! from a plurality of lines. : This relates to a method for multiplexing data into a single line and efficiently transmitting data to a processing device installed in a remote location.

(Prior art) Conventional frame multiplexing methods include a method in which the line between a multiplexer and a processing device at a remote location is time-divided, and each time slot is fixedly assigned to an accommodation line. A method was adopted in which a line identification number was added to the signal received from the network and transferred in packet multiplex format. The former identifies the line accommodating position by the time slot position, and the latter identifies by the line identification number.

(Problems to be Solved by the Invention) However, in the former method, the time slots of the line between the frame multiplexing device and the processing device are fixedly allocated to the accommodation line, resulting in a decrease in the efficiency of use of the surroundings. Also, the line usage rate? If you lower the line speed to increase the speed, the communication speed will decrease. In the latter case, the frame received from the accommodation line can be sent using any time slot, so it does not have the drawbacks of the former case, but it adds an accommodation line identification number to the frame and You will need a function to delete it. In addition, a new frame check sequence (Fe2) calculation is required between the frame multiplexing device and the higher-level processing device in order to check for errors in the added accommodated line identification number.

An object of the present invention is to make it possible to identify the line accommodation position of the frame multiplexer based on the time slot position of the line between the frame multiplexer and the processing device that have started receiving frames, and to When a frame is transferred between a line accommodated in a device and a processing device, each accommodated line shares all time slots for transfer, thereby preventing a decrease in line usage efficiency.

(Means for Solving the Problems) The present invention provides a time slot for starting frame transmission that is fixedly assigned to each accommodation line when frames received from a plurality of accommodation lines are multiplexed onto one line and transmitted. The most important feature is that transmission of frames on the accommodation line is started from , and that subsequent time slots are exclusively used for transmission until the transmission is completed. In the past, only the time slots in which transmission could begin were fixedly assigned to each accommodation line.
The difference is that the time slots that can be transmitted are not fixedly assigned to each accommodation line.

(Operation) According to the present invention, identification of the accommodation line is performed by the time slot at the start of transmission, and once transmission is started, subsequent time slots are used continuously. Therefore,
Address information that can be used to identify accommodation lines without reducing line usage efficiency or communication speed due to separate use of time slots for each accommodation line, as in the case of general packet multiplex transfer. To enable multiple transmission of frames without the need for attachment.

(Embodiment) FIG. 1 is a diagram showing an embodiment of the present invention, in which 1 is a frame multiplexing device, 2 is a line accommodated in 1, and 3 is a transfer of signals received from each accommodated line to a buffer memory. 5 is a buffer memory used to transfer frames from 1 to 8, 6 is a multiplexing/distribution circuit, 7 is a line between the upper processing unit, and 8 is installed in a remote location. Processing device, 9 is a multiplexing/distribution circuit in the processing device, 10 is H
A DLC processing circuit, 11 a processor bus, 12 a processing processor, and 13 a buffer memory used when transferring frames from 8 to 1.

Frames received from line 2 are transferred to buffer memory 5 by 3 and stored therein. Each time slot on line 7 is allocated to each accommodation line 2 as a time slot in which to start transmitting frames received from that line, and 6 is a line corresponding to that time slot for each transmission time slot of 7. It checks whether there is a frame received from , stored in 5, and waiting to be transmitted to 7, and transmits all of the signals using subsequent time slots consecutively. Once the frame has been transmitted, a flag pattern is transmitted. While the frame is being transmitted, the presence or absence of 5 frames waiting to be transmitted is not checked. When the transmission of one frame is completed, it is received again from the corresponding line 2 for each time slot, and it is checked whether there is a frame waiting to be transmitted to 7 stored in 5. If there is, it is sent to the next time slot in the same way. Use to send frames continuously. 9 monitors the signal received from 7, and senses that a frame has been received when the flag pattern is interrupted. 10 is line 2 and 1
The accommodating line number of 2 is identified by the time slot in which reception of the 9+t frame starts, and the frame is transferred to 10 corresponding to that line. After 1o performs HDLC procedure processing, it is transferred to 12 via 11.

12 further performs upper layer processing and then transfers the signal to another processing device. Conversely, from 8 to 1, 2
In some cases, frames may be transferred to In this case, 0 is 13 (if the frame is transmitted from 1 to 8 after transmitting and accumulating the c frame, and when the frame is transmitted in the manner of mouth j, and when 6 receives the frame, it is the time slot at which reception started) [Send directly to the corresponding line 2.]

FIG. 2 shows the flow of frames above 7.

Line 1 is associated with time slot a, line 2 with time slot b, line 3 with time slot C, and line 4 with time slot d. After the signal received from line 2 is stored in the buffer memory, transmission starts from time slot b and is transmitted using time slot cod. Similarly, the signal received from line 1 starts transmitting from time slot a) and time slot a) b + c.
use. The same applies below. Note that the top time slot 7 is used as a synchronization signal. With such a structure, each time slot of 7 can be shared to transfer the signal of each accommodation line, and there is no need to add an accommodation port@identification number to the frame on 7. As is clear from this result, frame multiplex transfer can be realized without requiring a line identification code addition/deletion circuit and a circuit to check for errors in the code, and without causing a decrease in the efficiency of use of 7.

(Effects of the Invention) As explained above, the device that receives the frame can identify the line number based on the position of the time slot where reception started, and the frames sent and received between each accommodation line and the remote processing device are frame multiplexed. This is possible by sharing all the time slots on the line between the converter and the processing unit for transmission and reception, so there is no need to add an accommodating line identification number, and it is possible to improve line usage efficiency by sharing time slots. can do.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of the apparatus of the present invention, and FIG. 2 is a diagram showing how to use multiplexed lines. In FIG. 1, 1 is a frame multiplexing device, 2 is a line accommodated in 1, 3 is a DMA circuit for transferring signals received from each receiving port to a buffer memory, 5 is a buffer memory, and 6 is a multiplexer. reference numeral 7 indicates a circuit for connecting to a higher-level processing device, 8 indicates a processing device installed in a remote location, 9 indicates a multiplexing/distribution circuit within the processing device, 10 indicates an HDLC processing circuit,
11 is a processor bus, 12 is a processing processor, and 13 is a buffer memory used when transferring frames from 8 to 1.

Claims (1)

[Claims] Signal frames from each line are multiplexed onto one line and transferred to a processing device installed at a remote location, and conversely, signal frames sent multiplexed from the remote processing device are distributed to each communication line. In a frame multiplexing device that has the function of transmitting data, a line between the frame multiplexing device and a processing device at a remote location is used in a time-division manner, and each storage stored in the buffer memory within the frame multiplexing device is transmitted over the line. Fixedly assign a time slot to start transmitting received frames from the line to each accommodated line, wait for frame transmission until that time, and start transmitting frames using the once assigned transmit start time slot. Then, the subsequent time slots are used continuously for transmission, and the processing device on the receiving side identifies the line number accommodated in the frame multiplexing device based on the position of the first time slot of the received frame, and conversely processes it. A frame multiplex transfer method characterized in that a similar method is used when transferring from a device to a frame multiplexer.