JPH01112844A - Communication control equipment - Google Patents

Abstract

PURPOSE:To easily specify a part in which a trouble occurred, and at the same time to extreme ly reduce a busy line by connecting many line interface parts to one wire transmission line through transmitting and receiving parts, provided at the communication control part sides of the respective line interface parts, and performing the collection of supervisory information inside a device and the transmission and the reception of busy information by using those interface parts in the way of time division. CONSTITUTION:A signal transmission system is constituted of a time-division multiplex control part 10, the many transmitting and receiving parts and one transmission line 1 to connect between both. The time-division multiplex control part transmits a bit synchronization pattern and a frame synchronization pattern to the wire transmission line at a definite frame period, and the transmitting and receiving part establishes bit synchronism according to those. In every frame, the time-division multiplex control part designates one of the transmitting and receiving parts by a first time slot previously determined in this frame, and transmits the supervisory information to the wire transmission line, and in response to it, the transmitting and receiving part transmits answer information to the wire transmission line by the second time slot previously determined in the frame. The time-division multiplex control part takes in it, and executes the test of a transmission system. The respective transmitting and receiving parts perform the transmission and the reception of the busy information by using one wire transmission line in the way of the time division.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a communication control device, and more particularly to a collection control technique for busy information indicating the usage status of a communication line and monitoring information inside the device.

(Prior Art) As is well known, a communication control device is a device placed between a communication line and a host computer, etc., and has an interface function with the communication line (line interface section) and an interface function with the host computer etc. (host interface section) and communication control function (communication control section).

Although a large number of line interface units perform the required operations under the control of one communication control unit, each line interface unit does not have a one-to-one correspondence with a communication line, but only one communication line. A plurality of line interface units are associated with each line interface unit. In other words, the communication control unit performs line connection control for multiple line interface units that share one communication line, and sends and receives busy information via any of the line interface units within this unit. It has become. Therefore, since one busy line is provided in common for a plurality of line interface sections constituting one unit, the number of busy lines is equal to the number of communication lines.

(Problems to be Solved by the Invention) As described above, in the conventional communication control device, G-lines are required for the number of communication lines, so when increasing the number of communication lines, G-lines are also required. It is necessary to add the same number of additional lines. As the number of signal lines increases, the failure rate also increases, which is a problem. In addition, the conventional fault detection method is to detect the occurrence of a fault when the signal transmission from the line interface section on the busy line is interrupted and this continues for a specified time; however, in this method, the busy line is If this occurs, or if a failure occurs in the transmitting/receiving function for the G-line in a particular line interface, it is extremely difficult to identify the location where the failure has occurred.

The present invention was devised in view of these conventional problems, and its purpose is to significantly reduce the number of busy information transmission lines (signal lines) required between the communication control unit and the line interface unit. In addition, it is an object of the present invention to provide a communication control device that is capable of detecting a disconnection fault in the transmission line and detecting a specific interface section that has caused the fault.

(Means for Solving the Problems) In order to achieve the above object, the communication control device of the present invention has the following configuration.

That is, the communication control device of the present invention includes a large number of line interface units and a number of line interface units that are connected to n(
(n is the number of communication lines) In the grouped n line interface units, one line interface unit is used as a unit to control line connection with one communication line, and any one of the line interface units in the line interface unit group is controlled. A communication control device comprising: a communication control unit that sends and receives busy information via a line interface unit;
The plurality of line interface units are each provided with a transmitting/receiving unit on the side of the communication control unit, and one
The bit synchronization pattern and the frame synchronization pattern are transmitted to the wired transmission path at a constant frame period, and one transmitting/receiving unit is connected at a predetermined first time slot within the frame. When specifying , the monitoring information is sent to the wired transmission path, and the corresponding transmitting/receiving section captures the response information sent to the wired transmission path in a predetermined second time slot in the frame to test the transmission system. A division multiplexing control section is provided; the transmitting/receiving section includes bit synchronization means for regenerating a transmitting/receiving clock used in the wired transmission line based on the bit synchronization pattern taken in from the wired transmission line and establishing bit synchronization; time slot identification means for identifying a time slot position within a frame based on a frame synchronization pattern; and taking the monitoring information sent to the wired transmission line in the first time slot and receiving the response information when the monitoring information is addressed to the self. and a response control means for generating and transmitting it to the wired transmission line in the second time slot; a time slot assigned to the line interface group to which the self belongs among the n time slots set within the frame; The present invention is characterized by comprising: a busy information transmitting/receiving means for exchanging busy information with a wired transmission line;

(Function) Next, the function of the communication control device of the present invention configured as described above will be explained.

The time division multiplexing control unit sends a bit synchronization pattern and a frame synchronization pattern to the wired transmission line at a constant frame period, and the transmitting and receiving unit transmits the bit synchronization pattern and frame synchronization pattern to the wired transmission line based on the bit synchronization pattern taken in from the wired transmission line for each frame. Regenerate the transmit and receive clocks used and establish bit synchronization (
(bit synchronization means) and identifies the time slot position within the frame based on the frame synchronization pattern taken in from the wired transmission line (time slot identification means).

Then, in each frame, the time division multiplexing control unit performs one
Specify one transmitter/receiver and send the monitoring information to the wired transmission path. Then, the transmitting/receiving unit takes in the monitoring information sent to the wired transmission line in the first time slot, creates response information when it is addressed to itself, and transmits it at a predetermined second time within that frame. As a result, the time division multiplexing control unit receives the response information sent by the corresponding transmitting/receiving unit to the wired transmission line in the second time slot and transmits it to the wired transmission line in the second time slot (response control means). This means that the test can be conducted.

Since this is performed for all the transmitting/receiving sections, it is possible to identify the transmitting/receiving section in which the fault has occurred, and it is also possible to detect a disconnection fault in the wired transmission line.

On the other hand, the transmitter/receiver can exchange busy information with the wired transmission path in the time slot assigned to the line interface group to which it belongs among the n time slots set in the frame (busy information sending/receiving means). That is, since each transmitter/receiver can transmit and receive busy information by using one wired transmission line in a time-division manner, only one busy line is required.

As explained above, according to the communication control device of the present invention,
A large number of line interface units are connected to a single wired transmission line through transmitting/receiving units provided on each communication control unit side, and this wired transmission line is used in a time-sharing manner to collect monitoring information inside the device. This is done for each transmitting/receiving unit, as well as sending and receiving busy information, which not only makes it possible to easily and reliably identify the location of a failure, but also significantly reduces the number of g-lines between the line interface unit and communication control unit to one. In addition, when lines are added, there is no need to add a busy line, and it can be easily handled by simply adding a time slot within the frame, which can significantly reduce the failure rate related to signal line wiring. effective.

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

The present invention provides a number of line interface units and a number of line interface unit groups in which the number of line interface units are grouped into n groups (nJ number of communication lines). In a communication control device that is equipped with a communication control section that performs line connection control with a line, etc., and sends and receives busy information via any line interface section in the group of line interface sections, This relates to a signal transmission method for transmitting busy information and monitoring information between communication control units.

This signal transmission method, as shown in FIG.
..., the same noo to the same neo, and one transmission line 1 connecting these two.

The time division multiplexing control section 1o is provided either on the communication control section side or on the line interface side (neither is shown), but considering its function, it is better to provide it on the communication control section side. The unit 10 basically includes a control circuit 11, and a transmitting circuit 12 and a receiving circuit 13 which are under the control of the control circuit 11 and exchange signals with the transmission line 1, and handle frame management on the transmission line 1 and the transmission concerned. The structure of the transmission frame, which mainly monitors the system, is shown in Figure 2 (a).
), one frame consists of a bit synchronization slot, a frame synchronization slot, a monitoring information slot, n time slots, and a response information slot. The bit synchronization slot is a time slot for each transmitter/receiver to establish bit synchronization and form an operating clock. The frame synchronization slot is a time slot for enabling time-division use of the transmission line 1. The monitoring information slot is a first time slot and is used to test the transmission system. The n time slots are used for transmitting and receiving busy signals. This is provided for the number of communication lines. The last response information slot is the second time slot and is used by the designated transceiver. One monitoring information slot and one response information are provided in one frame.

On the other hand, the transmitting/receiving section (100~1mO, -, n00~n L
O> are provided on the communication control unit side of the corresponding line interface unit (not shown).

That is, the m transmitting/receiving units from transmitting/receiving unit 100 to 1mO are for a group of m line interfaces that share the first communication line, and the first time slot among the n time slots is 1 is assigned.

Similarly, L transmitting/receiving units from n00 to nLO are for L line interface groups that share the nth communication line, and are for the nth time of the n time slots. Slot n is assigned. Each transmitter/receiver has a similar configuration, and has a control circuit (101
~1ml, -, no1~n Ll) and a transmitting circuit (1
02~1m2. ....

no2~nL2) and receiving circuit (103~1m3.・
.

In the above configuration, the time division multiplex control unit 1o first forms a predetermined bit synchronization pattern (a clock pattern in this embodiment) and sends it to the transmission line 1 in the bit synchronization slot located at the beginning of each frame. do. Then, in each transmitter/receiver section, each receiving circuit (103~1m3.-
, no3 to n L3) have an operating clock regeneration circuit as shown in Fig. 3, which regenerates the operating clock from the clock pattern taken in from the transmission line 1, that is, establishes bit synchronization and reproduces it within the period of one frame. The required operations will be performed according to the operating clock.

Next, the time division multiplex control unit 10 forms a predetermined frame synchronization pattern and sends it to the transmission path 1 in a frame synchronization slot following the bit synchronization slot. Then, each transmitting/receiving unit selects at least the monitoring information slot based on the frame synchronization pattern taken in from the transmission path 1.
The time slot position of each time slot (one of time slots 1 to n) and response information slots assigned to the line interface unit group to which it belongs is identified.

Then, the time division multiplex control unit 10 sends the monitoring information to the transmission path 1 in the monitoring information slot following the frame synchronization slot. The monitoring information may be only the address information of one transmitter/receiver to be received, but specific monitoring items may be added to the address information.

The operations described above are repeated for each frame,
The signal form on the transmission path 1 is as shown in FIG. 2(b). The monitoring slot of each frame is received by all transmitting/receiving units, and the address information included in the monitoring information determines whether the frame is addressed to itself or not.The designated transmitting/receiving unit creates response information for the monitoring item and sends it to itself. Forms response information with address information added (if the monitoring information is only address information, the response information only needs to be address information), and sends it to transmission path 1 in the response information slot, which is the final time slot of the same frame. (Figure 2(e)).

As a result, the time division multiplex control unit 10 can test the normality of the transmission system by confirming that response information is correctly returned from one transmitter/receiver in each frame. By monitoring the address information in the response information sent back from each transmitter/receiver, it is possible to determine whether or not a fault has occurred in the transmission line 1, and if a fault occurs, to identify the location of the fault, as well as to identify the occurrence of an abnormality. It is possible to determine which transmitter/receiver unit is responsible for the failure, and furthermore, by decoding the response information in the response information, the extent of the failure can be easily determined, and fine-grained failure handling can be performed.

On the other hand, the busy signal may be generated by a remote terminal or a communication control unit. When a terminal in a remote location generates a busy signal, the busy signal is input to the control circuit of the corresponding transmitting/receiving unit via a communication line and one line interface unit in a group of line interface units that use that communication line. It looks like this. Therefore, the control circuit of the corresponding transmitter/receiver unit sends out the input busy signal to the transmission path 1 in a predetermined time slot (one of time slots 1 to n) (see Fig. 2). (d)) The trace signal sent to the transmission line 1 is received and received by the communication control section. On the other hand, when the communication control unit generates a busy signal, it is sent to the transmission line 1 in a predetermined time slot, so the busy signal on the transmission line 1 is taken in by the transceiver unit belonging to that time slot. The information is transmitted to the corresponding line interface unit via the control circuit.

In short, by using one transmission line in a time-division manner, it is possible to handle busy signals for n lines.

Finally, as shown in FIG. 3, the aforementioned operating clock regeneration circuit includes a shift register circuit d, a tarlock pattern detection circuit f, a 1/N frequency divider circuit C, a shift register circuit e, and a latch circuit g. and the clock phase difference detection circuit.
It basically consists of an encoder circuit i and a selector circuit j.

The built-in clock b has a frequency that is an integral multiple of the transmitting and receiving clock on the transmission line 1, and is supplied to the 1/N frequency divider circuit C, and is also supplied to the shift register circuits d and e as a sampling clock.

The shift register circuit d samples the received signal a taken in from the transmission line 1 using the built-in clock b, outputs it serially and sequentially to form a received signal, and also outputs the contents of a predetermined number of shift stages in parallel. Output to clock pattern detection circuit f.

The clock pattern detection circuit f has a clock pattern to be detected set in advance, determines whether or not this clock pattern matches the input parallel output signal, and outputs a matching pulse to the latch circuit g when they match. .

Further, the 1/N frequency divider circuit C divides the built-in clock b by 1/N to form a clock having the same frequency as the transmission/reception clock (however, the phase is different), and supplies it to the shift register circuit e.

The shift register circuit e samples the output clock of the 1/N frequency divider circuit C using the built-in clock b, and outputs the contents of a predetermined number of shift stages in parallel to the latch circuit g and the selector circuit j.

As a result, the latch circuit g latches the parallel output signal of the shift register e in response to the input of the coincidence pulse, and sends it to the clock phase difference detection circuit. In other words, the latch circuit g latches the clock pattern sent onto the transmission line 1 in the bit synchronization slot, although the phase is different.

The clock phase difference detection circuit compares the latched output clock pattern with the original clock pattern (preset), detects the phase difference, and provides it to the encoder circuit i.

Encoder circuit i encodes the contents of the given phase difference and provides it to selector circuit j.

The selector circuit j selects the clock with the smallest phase difference from the clock pattern appearing in the received signal t among the clocks of various phases outputted in parallel by the shift register circuit e, and reproduces it. Output as clock.

In order for the clock pattern detection circuit f to correctly detect the tarokk pattern, it is necessary to place restrictions on the bit patterns that can be used in the monitoring information, busy signal, and response information included in the received signal a.

(Effects of the Invention) As explained above, according to the communication control device of the present invention,
A large number of line interface units are connected to a single wired transmission line through transmitting/receiving units provided on each communication control unit side, and this wired transmission line is used in a time-sharing manner to transmit and receive monitoring information inside the device. Since this is done for each section and busy information is exchanged, it is not only possible to easily and reliably identify the location of a failure, but also to greatly reduce the number of lines between the line interface section and the communication control section to one. , and when lines are added, there is no need to add a busy line, and it can be easily handled by simply adding a time slot within the frame, which has the effect of significantly reducing the failure rate related to signal line wiring. There is.

[Brief explanation of the drawing]

FIG. 1 is a configuration block diagram of a signal transmission method implemented in a communication control device of the present invention, FIG. 2 is a time chart of transmission and reception, and FIG. 3 is a configuration block diagram of an operating clock recovery circuit. 1...Transmission path, 10...Time division multiplex control unit, 11.101.1ml, nol, n Ll...
...Control circuit, 12,102.1m2. n02.
nL2...Transmission circuit, 13,103.1m3
．． n03゜n L 3----...Reception circuit, 100
．． 1 mO, noo. nLO... Transmitting/receiving section, a, -L...
・Received signal, b...Built-in clock, C. Old.
・17N frequency divider circuit, d, e...shift register circuit, f...clock pattern detection circuit,
g...Latch circuit, h...Clock phase difference detection circuit, i...Encoder circuit,
j...Selector circuit, k...Regeneration clock. Agent Patent Attorney Yoshihiro Hachiman

Claims (1)

[Claims] A line between a large number of line interface units and one communication line using one line interface unit group as a unit in n line interface unit groups in which the large number of line interface units are grouped into n groups (n is the number of communication lines). In a communication control device comprising a communication control unit that performs connection control, etc. and also transmits/receives busy information via one of the line interface units in the line interface unit group; A transmitting/receiving section is provided on the control section side, and is connected via one wired transmission path through the transmitting/receiving section; while transmitting a bit synchronization pattern and a frame synchronization pattern to the wired transmission path at a constant frame period, One transmitter/receiver is specified in the first predetermined time slot in the frame and the monitoring information is sent to the wired transmission path, and the corresponding transmitter/receiver is designated in the second predetermined time slot in the frame. A time division multiplexing control unit is provided that takes in response information to be sent to the transmission line and tests the transmission system; bit synchronization means for reproducing and establishing bit synchronization;
a time slot identification means for identifying a time slot position within a frame based on a frame synchronization pattern taken in from a wired transmission path; response control means for creating the response information and transmitting it to the wired transmission line in the second time slot; A communication control device comprising: busy information transmitting/receiving means for exchanging busy information with a wired transmission line in an assigned time slot.