JPS58171151A - Device for branching/inserting data - Google Patents

Abstract

PURPOSE:To simplify the change of a part to be connected in loop transmission, the change of a parameter, etc. by assigning a part to perform branching and insertion and a common bus line to transmit/receive signals to/from terminals to each node in a loop transmission system. CONSTITUTION:A transmission line interface 2 is continuously connected to a loop 1. A signal received by the transmission line interface 2 through a received data separating circuit 8, a selector 10 and a transmission data inserting circuit 9 is transmitted to the loop 1. The received data separating circuit 8 separates an address signal and data from a received TDM signal and impresses the separated signals to an address line ADD and a received data line RED of buses. A terminal reads out data coincident with the self-address. When a signal is to be sent from the terminal, a signal is outputted to a transmission request line RQS to switch the selector 10 and data are impressed to a transmission data line TRD, so that the transmission data are converted into a TDM by the inserting circuit 9 through the selector 10 and transmitted to the loop.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Technical Field of the Invention The present invention relates to a loop transmission system, and in particular to a data branching system in which data at a plurality of transmission speeds is branched or inserted from data on the loop transmission line using a time division multiplexing method. , relating to an insertion device.

(2) Technical background There are various methods for data transmission. One such method is a loop transmission method. In this method, devices that send and receive data are connected in series with the signal flow, and the last device is connected to the first device, that is, the data is transmitted through a transmission system connected in series in a loop. .

Furthermore, this method requires a circuit for branching data required by the terminal device from the loop system, and a data insertion circuit for transmitting data from the terminal device to another terminal device.

The data transmission speed of a terminal device connected to this loop system is not necessarily equal to the transmission speed of the loop system. For example, the data terminal line is 300 to 9600 bit/se
c. The transmission speed of an audio line is 64 Kbit/sec, which is different from that of a loop system, for example, 8 Mbit/sec.

(3) Conventional technology and problems Conventionally, data branching of different data transmission speeds.

As an insertion method, there is a mixed speed branching and insertion method.

This method further includes a multi-point sampling method and a dedicated area method in which the area of the data frame is divided and a dedicated area is used for a group of data having the same speed.

The multi-point sampling method uses data lines inefficiently,
The dedicated area system has the disadvantage that there are many restrictions on the lines that can be used, and operations such as adding to the loop system or relocating it within the loop, such as changing circuits within the device, are complicated.

(4) Purpose of the Invention The present invention solves the above-mentioned problems, and its purpose is to independently provide data branching and insertion;
It is an object of the present invention to provide a data branching/insertion device which makes it extremely easy to add or relocate terminal devices to a loop transmission system by connecting them with a path line.

(5) Structure of the Invention The characteristics of the present invention are that, in a device inserted into a time division multiplexed loop transmission line and transmitting and receiving data, a transmission line interface that transmits and receives data to and from the loop transmission line; a receive data separation circuit that outputs the received data and address obtained from the path to the path line; a selector that selects the received data and the transmitted data of the path line by a transmission request line of the path line; and the output of the selector is connected to the transmission line interface. and an interface circuit that is connected to a terminal device and sends and receives data from the terminal device to a path line, and the path line includes an address line, a sending data line, and a receiving data line. , a transmission request line, and when the selector receives a transmission request signal from the transmission request line of the path line, it selects the transmission data line of the path line, and when it does not receive the transmission request signal, it selects the reception data line of the path line. The interface circuit has the function of transferring data between the terminal device and the path line when specified by the address line of the path line.

It is in the insertion circuit.

(6) Examples of the invention Hereinafter, detailed explanation will be given using examples of the present invention.

FIG. 1 shows an embodiment of the invention. The loop transmission line 1 is connected to a transmission line input 3 and a transmission line output 4 of a transmission line interface 2. The common section 7 includes a received data separation circuit 8. Transmission data insertion circuit 9. Consists of 10 selectors. The local output 5 of the transmission line interface 2 enters the local input 10 of the received data separation circuit 8, and the local output 11 of the transmission data insertion circuit 9 enters the local input 6 of the transmission line interface 2. Bus output 1 of received data separation circuit 8
2.13 is the address line ADD of the pass line Bus.

The inputs 14 of the transmission data insertion circuits 9 connected to the reception data lines RED are the selection output terminals 15 of the selector IO.
connected to. Selection input terminals 16 and 17 of selector 10
are the reception data line RED of the pass line Bus, respectively.
Each is connected to the transmission data line TRD. Selector 1
0 control input 18 transmission request line RQ of bus line Bus
S enters. Each interface circuit 19, 19'... of the line section 21 is connected to the pass line Bus,
The output 20.20' is the corresponding terminal device (
(not shown) are connected.

The transmission line interface 2 performs conversion and inverse conversion of transmission line code formats, such as bipolar signals and optical signals. The received data separation circuit 8 performs frame synchronization from the received data obtained from the transmission line interface 2, that is, the converted data, and sends the address data indicating the time slot position and the received data to the address line AD of the path line Bus.
I) and the received data line RED.

The transmission data insertion circuit 9 multiplexes the transmission data input from the input 14, adds a frame synchronization flag, etc., and outputs the data to the transmission line interface 2.

If there is a transmission request from the transmission request line RQS, the selector 10 selects the transmission data on the transmission data line TRD and outputs it to the transmission data insertion circuit 9. If there is no transmission request, the reception data line RED is selected and output.

Each of the interface circuits 19 and 19' of the circuit section 21 has an address setting function that determines which time slot of the loop transmission path 1 data is to be inserted into. When the output address signal matches the set value, data is taken in from the reception data line RED, and the data is output to the transmission data line TRD, and at the same time, a transmission request signal is output.

Data on the loop transmission line in the data branching and inserting device of the present invention is time-division multiplexed, and specific time slots correspond to addresses of the interface circuits 19, 19', etc.

FIG. 2 shows a data multiplexing configuration according to an embodiment of the present invention. This configuration is a configuration for multiplexing data when transmission speeds are different. The basic frame SF is, for example, 125μse
c, and in the example of FIG. 2 where a plurality of these basic frames SF are collected to form a multi-frame MF, 20 basic frames SF are collected to form the multi-frame MF.

This multi-frame is sequentially and repeatedly transmitted to the loop transmission line 1. If one multi-frame MF is 2.5 msec, it is transmitted 400 times per second.

The basic frame SF consists of 8 bits of data per data line. For example, in the case of a data terminal that inputs and outputs character data, data LD is inserted into a specific time slot of the basic frame SF.

Note that bit C1 and bit C2 are control bits from the data terminal, and bits D1 to D6 are data bits. Furthermore, for example, in the case of a voice terminal device, the data is voice PCM signal %SD, and 8-bit data D
It is composed of 1 to DB. If the transmission rate of the loop transmission path is 8 Mbit/sec, the basic frame consists of approximately 128 bytes, and if the transmission rate is 2 Mbit/sec, it consists of 32 bytes.

In the above-mentioned time division multiplexing, the transmission rate of the data terminal is 24
00 baud (bit/sec), it is sufficient to allocate one time slot to one multiframe.
If the audio PCM signal is 64 baud, one time slot may be allocated to one basic frame.

FIG. 3 shows a system configuration using an embodiment of the present invention.

Set the terminal station N1 connected in a loop. Since the line unit having this address is not installed in the terminal station N2, the transmission request is not turned on, and the data from the terminal station N+ is directly bypassed and received by the terminal station N3.

(7) Effects of the Invention The present invention provides branching of loop transmission data by the transmission interface connected to the loop transmission path and the common part 7.
The common part has a pass line. As a result, the above-mentioned circuit can be used commonly for loop transmission, that is, it can be configured with one type of circuit, and by providing the interface circuit with a parameter setting function such as speed, it is possible to change the connection destination in the loop transmission system. , parameters can be changed easily.

[Brief explanation of the drawing]

FIG. 1 is a circuit configuration diagram showing an embodiment of the invention, FIG. 2 is a data configuration diagram of the embodiment of the invention, and FIG. 3 is a system configuration diagram of the embodiment of the invention. 2...Transmission line interface, 7...Common part,
8... Reception data separation circuit, 9... Transmission data insertion circuit, 10... Selector, 19.19"...
Interface circuit, Bus...pass line. Patent applicant Fujitsu Limited

Claims (1)

[Scope of claims] In a device inserted into a time-division multiplexed loop transmission path to send and receive data, a transmission path interface that sends and receives data to and from the loop transmission path, and received data and addresses obtained from the transmission path. a receive data separation circuit that outputs the received data to the pass line, a selector that selects the receive data and the transmit data of the pass line by a transmission request line of the pass line, and transmits the output of the selector to the loop transmission line via the transmission line interface. and an interface circuit connected to a terminal device to transmit and receive data from the terminal device to a path line, the path line consisting of an address line, a transmission data line, a reception data line, and a transmission request line,
When the selector receives a transmission request signal from the transmission request line of the pass line, the selector selects the transmission data line of the pass line;
The interface circuit has a function of selecting the reception data line of the pass line when the transmission request signal is not received, and transferring data between the terminal device and the pass line when specified by the address of the address line of the pass line. Data branching featuring. Insertion circuit.