JPS6286946A - Line connection switching system - Google Patents

Abstract

PURPOSE:To reduce the quantity of hardware of a communication control equipment by providing a driver/receiver corresponding to the interface of a communication line and a communication line common to the driver/receiver in a line connecting unit, and providing a switching means that selects one of communication lines between the driver/receiver and the communication line. CONSTITUTION:In a communication system between a host 1 and a CPU 12, a line switching device 6 selects a specified communication line 5 by a switching control signal 13 outputted from a CP 11 basing on the control of the CPU 12, and the specified communication line 5 is connected to the interface driver/ receiver 8 by a line interface switching circuit 14. When a fault is occurred in the specified communication line 5 or a MODEM 2, the CP 11 rewrites the register of an LSI 10 for communication so as to match the content of parameter of the circuit specification with a communication circuit for backing up. Then, the CP 11 outputs a switching control signal 13 that the communication circuit and circuit interface are switched mutually against the circuit switching device 6 and circuit interface switching circuit 14.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a line connection switching system for communication lines of different interfaces in a communication control device.

(Conventional technology) Conventional communication lines with different interfaces? When connected to a communications control device, each interface was an independent line interface, connected to a separate line channel.

FIG. 2 shows a block diagram of communication lines of different interfaces, a line connection method of communication control devices, and a communication system. As shown in the figure, a host computer (hereinafter referred to as host) 1 and a central processing unit (hereinafter referred to as CPU)
In the 12 communication systems (hereinafter abbreviated as CCE), a communication control device (hereinafter abbreviated as CCE) 30 is provided between them. C.C.
The E30 connects and accommodates communication lines of different interfaces from the host 1, one of which is a specific communication line 5 equipped with a modem 2. The other communication line is a backup communication line used when the specific communication line 5 or modem 2 fails. This backup communication line uses a line termination unit (hereinafter referred to as DSU) that uses the DDX network 4.
(abbreviated as ) 3).

The internal configuration of CCE20 is CCI for specific communication line 5.
Line connection unit 1 with TTV28 interface standard
5, a line connection unit 16 of CCIT TV II interface standard for backup communication line, and CCE3.
A common control section (hereinafter abbreviated as CP) 11 controls the entire operation of the 0. Furthermore, the line connection unit 15 has a CCITTV28 standard interface driver/
The receiver 8 and the interface driver/communication LS 118 that is connected to the receiver 8 and performs communication control based on its specifications, and the line connection unit 16 is a CCIT TV II standard interface driver/LS 118 that performs communication control based on the specifications.
It is composed of a receiver 9 and a communication LS 119. In this communication LS 118°I9, various line specification parameters such as data transfer speed and data synchronization method are set and registered in internal registers.

The CCE 30 having such a configuration is connected to the CPU 12 through the data channel 17 which instantaneously exchanges data, and is controlled by the software of the CPU 1.2. This software is for switching and controlling the line connection units 15 and 16, for example.

In the above communication system configuration, the CPU 12 and the host 1 are logically connected.

Next, the operation of a communication system using a conventional line connection method will be explained.

Typically, communication data from a host is input to an interface driver/receiver 8 of a line connection unit 15 via a specific communication line 5. The interface driver/receiver 8 that you received from Bootara is the communication LS118.
provides an electrical interface for the data. Communication LSI 1.8 is under the control of CPll,
Adjust the speed and synchronization of the data to be transferred, and then transfer the data. The transferred data is sent to the CPU 12 via the data channel 17 via the CPII. On the other hand, when outputting data processed by the CPU 12,
The PU 12 is connected to the line connection unit 15 by software.
Performs all logical conversions of the port addresses, and outputs a command to use all line connection units 15 & CP11. the result,
The output data from [CPU]2 is sent to the CPll that received the command.
The data is distributed to the line connection unit 15 under the control of the communication line 5, and sent to the host 1 via the specific communication line 5.

Next, consider a case where a failure occurs in the specific communication line 5 or modem 2. In this case, the data processed by the communication LSI 8 and sent to the CPU 2 is
It is detected by the software No. 2 that there is an abnormality in the data. Then, as described above, the CPU 12 uses the software to logically convert the address of the line connection unit 16, and outputs a command to use the line connection unit 16 to the CPII. The CPII that received the command
12 is distributed to line connection unit I6. As a result, communication between the host] and the CPU]2 is performed using the communication line for the pack amplifier.

(Problems to be Solved by the Invention) However, the line connection method in the communication system as described above has the following problems.

Since the backup communication lines using the specific communication line 5 and the DDX network 4 have different interfaces and are connected to and accommodated in the communication control device 30, the line connection units 15 and 16 are connected to each other according to the respective interfaces.
In addition, communication LS Ik must be used individually for each line unit (15, 16), which poses a problem in that the amount of hardware increases.

Also, the line connection units 15 and 16 seen from the CPU 12
Since each port address is different, the software of the CPU 12 performs logical conversion of each port address to switch and control these line units 15 and 16. Therefore, the software user program (
There was a problem that the burden on the AP ') was too heavy.

Furthermore, since it is necessary to prepare a line connection unit 16 for backup communication lines that are not normally used, the number of lines that can be accommodated by the communication control device is apparently reduced.
The problem was that it was limited.

The present invention eliminates the above-mentioned problems, creates a hardware configuration for the line connection unit without reducing the number of lines that can be accommodated by the communication control device, and further reduces the burden on the software of the CPU that controls the CCE as much as possible. The purpose is to provide a connection switching method.

(Means for Solving the Problems) According to the present invention, in order to solve the above-mentioned problems, there is provided a communication control device for connecting and accommodating communication lines of different interfaces, and a device connected to the communication control device. However, in a communication system that communicates using one of the communication lines of different interfaces, the following means are provided.

The line connection switching method of the communication system includes a driver/receiver that is individually provided in the communication control device corresponding to the interface of the communication line, and a driver/receiver that is individually provided in the communication control device corresponding to the interface of the communication line.
A line connection unit is provided in common with the receiver, and includes a communication circuit that performs communication control based on the interface specifications of the 1-in-1 communication line, and the communication line is connected between the communication line and the driver/receiver. A switching means is provided for selecting one of the following and connecting it to the corresponding driver/receiver.

(Operation) According to the present invention, since the line connection switching system is configured as described above, the operation is as follows.

The device connected to the communication control device described above is, for example, a central processing unit. The communication lines of different interfaces and the above-mentioned switching means provided in the communication control device select one communication line from the communication lines of different interfaces based on the output signal from the central processing unit, and switch the interface of the selected line. Connect the corresponding driver/receiver. As a result, communication with the central processing unit is performed using the communication line selected by the switching means.

Therefore, by providing the switching means, the line connection unit of the communication control device that connects the communication lines of different interfaces can solve the problems described above while improving the communication lines.

(Example) Hereinafter, the present invention will be explained in detail using an example with reference to FIG.

FIG. 1 is a block diagram showing a communication line, a line connection switching method of a communication control device, and a configuration of a communication system according to this embodiment. In this figure, the same components as in the configuration of the conventional line connection method shown in FIG. 2 described above are given the same reference numerals.

In a communication system of a host computer (hereinafter abbreviated as host) 1 and a central processing unit (hereinafter abbreviated as CPU) 12, a specific communication line 5 and a backup communication line are controlled by communication from the host via a line switching device 6. It is connected to a device (hereinafter abbreviated as CCE) 20. The line switching device 6 includes a common control unit (hereinafter abbreviated as CP) 11 of the CCE 20.
This is a device that switches communication lines using a switching control signal 13 output from a communication line. The inside of the CCE 20 is composed of a line connection unit 7 and a CPII. Furthermore, inside the line connection unit 7, there are an interface driver/receiver 8 based on the CCITTV28 standard, an interface driver/receiver 9 based on the CCITTV11 standard, a communication LS 110 that is connected to each interface driver/receiver 8 and 9 and performs communication control, and an interface driver/receiver 9.
It is composed of a line interface switching circuit 14 that switches between the receivers 8 and 9. The switching control signal 13 output from the CPII is input to the line switching device 6 and the line interface switching circuit 14. In such a communication system configuration, the host 1 and the CPU 12 are logically connected.

Next, the operation of the line connection type communication system according to this embodiment will be explained.

Usually, in the communication system between the host] and the CPU 12,
Based on the switching control signal 13 output from the CPII based on the management of the PUI 2, the line switching device 6 selects the specific communication line 5, and the line interface switching circuit 14 selects the specific communication line 5 and the interface driver/receiver 8.
is connected to.

Now, consider a case where a failure occurs in the specific communication line 5 or the modem 2. As mentioned above, this failure is caused by the communication L
An abnormality in the data transferred from the S I 10 to the CPU 12 is detected by the software of the ecPU 12. The CPU 12 that detected the failure
The following commands are all output to the PII based on the failure. The contents of this command are to change the contents of the line specification parameters initialized in the register of the communication LS 110, to switch the communication line, and to switch the interface driver/receiver. In response to the former command, the CP 11 rewrites the register of the communication LSI 10 so that the contents of the line specification parameters match the backup communication line. As mentioned above, the parameters include the data transfer rate, synchronization method, etc. in line specifications. Next, in response to the latter command, the CPII outputs a switching control signal 13i to the line switching device 6 and the line interface switching circuit 14, respectively, for switching between the communication line and the line interface. This signal causes the line switching device 6 and the line switching interface circuit 14 to operate, select a backup communication line, and connect the corresponding interface driver/receiver 9. CPU12
When the CP 11 receives the completion of the sequence of settings changes, line switching, etc. from the CP 11 as a command completion notification, communication with the host 1 is resumed.

As described above in detail, according to this embodiment, when a failure occurs in the specific communication line 5 or the modem 2, the CP
Based on the command from U 12, the line switching device 6 and line interface switching circuit 14 are operated, and the communication line can be automatically switched to the back amplifier communication line.

In this embodiment, the setting changes of the line specification parameters of the communication LSI 10 may be received by the CPll at the same time as a command from the CPU 12, or may be stored in advance in the local control information memory for the CP of the CPII. You can also register.

In this embodiment, two communication lines for different interfaces are used.
However, the communication line may have a plurality of different interfaces. In that case, an interface driver/receiver compatible with multiple communication lines and a common communication LSI are provided in the line connection unit, and a line switching device and a line interface switching circuit are used to connect one communication line and this communication line. You can select the corresponding driver/receiver and switch the communication line to be used.

In this embodiment, a single line switching device 6 that switches communication lines is used.
Although the line interface switching circuit 14 for switching the interface driver/receiver 8.9 is individually provided, the connection relationship between the communication line and the interface driver/receiver is uniquely determined, so the line switching device 6.
The line interface circuit 14 can also be replaced by a switching device having other configurations having these functions. Furthermore, if this switching device is installed between the communication line and the interface driver/receiver 8, 9, it is possible to
It may be provided either inside or outside. Similarly, the line connection device 6 and line interface switching circuit 14 also
It may be provided either inside or outside the CaF 22 as long as it is provided between the communication line and the interface driver/receiver.

(Effects of the Invention) As described above in detail, according to the present invention, the line connection unit of the communication control device is provided with one stage of switch for selecting the driver/receiver corresponding to the interface of the communication line. The effect is as follows.

(b) Since there is no need to have individual connection line units, the amount of hardware in the communication control device can be significantly reduced.

(b) When switching to select one communication line from different interfaces, the port address of the line connection unit seen from the CPU is specified, so there is no need for logical conversion of the port address by the CPU software, and the CPU directly With this command, it is possible to automatically switch to another communication line, which can be expected to have the effect of reducing the processing load of CPU notware and the switching time.

(c) Since there is no need to use dedicated line connection units for communication lines of different interfaces, there is an effect that the effective line channels of the communication control device are not reduced.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of a line connection switching system according to an embodiment of the present invention, and FIG. 2 is a block diagram showing the configuration of a conventional line connection system. ]...Host computer, 2...Modem, 3...
・Line termination unit (DSU), 4...DDX network, 5...
・Specific communication line, 6... line switching device, 7, 15
, 16... Line connection unit, 8, 9... Interface driver/receiver, 1.0, 18, 1.
9--Communication LSI; 11--Common control unit (CP)
, 12...Central processing unit (CPU), 13...Switching control signal, 14...Line interface switching circuit, 1
7...Data channel, 20, 30...Communication control device.

Claims (1)

[Claims] A communication system that includes a communication control device that connects and accommodates communication lines of different interfaces, and a device connected to the communication control device, and that communicates using one of the communication lines of different interfaces. In the communication control device, a driver/receiver is provided individually corresponding to the interface of the communication line, and a communication circuit is provided in common with the driver/receiver and performs communication control based on the interface specifications of the communication line. A line connection unit is provided, and a switching means is provided between the communication line and the driver/receiver to select one of the communication lines and connect it to the corresponding driver/receiver. Line connection switching method.