JPS6010943A - Line adaptor - Google Patents

Abstract

PURPOSE:To attain the connection of a DCE having various interfaces with a CCU by providing a line adaptor whose connecting state is changed by an RT signal from a line terminator (DCE) and an RS signal from a communication controller (CCU) between the CCU and the DCE. CONSTITUTION:When the DCE is a synchronism type MODEM, a line adaptor receives the RT signal from the DCE, and an FF3 is set, then a relay 13 is inoperative, and an NS signal and an ST1 signal are transmitted to the DCE. Since an input signal A is incoming, an FF2 is set, a relay 12 is inoperative and an RS signal is transmitted to the DCE. When the DCE is an asynchronous MODEM, since the RT signal is not inputted to the line adaptor, an FF3 is set and the relay 13 is operative, and the NS and the ST1 are not transmitted to the DCE. Since the A signal is not risen, the FF2 is reset, the relay 12 is operative and no RS signal is transmitted.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Technical Field of the Invention The present invention relates to a circuit for a line adapter installed in a line connection section of a communication control device and connected to a communication line via a line termination device such as a modem. It is.

(2) Prior Art and Problems Line termination devices such as modems use different types of control signals due to differences in control procedures. Table 1 shows the relationship between the types of line termination devices and control signals.

Table 1 In Table 1, A represents the line adapter side, T represents the line termination device side, and the arrow indicates the direction of the signal.

Further, a circle mark indicates that the corresponding signal is used, and a diagonal line indicates that the corresponding signal is not used.

Conventionally, dedicated line adapters have been manufactured for each of the above-mentioned types of modems, etc., which has the drawback of complicating design, management, etc. during product development and manufacturing.

(3) Purpose of the Invention In view of the above-mentioned drawbacks of the conventional art, it is an object of the present invention to provide a line adapter that can be used with a single type of modem, etc. with different control methods.

(4) Structure and object of the invention According to the present invention, as described in the claims, there is provided a line adapter that is located between a control unit of a communication control device and a line termination device and transfers signals. A circuit for controlling whether or not to send the NS signal, ST, and signals to the line terminating device depending on the presence or absence of the RT double signal from the line terminating device, and a line terminating device for sending the ER signal to the line terminating device. DR double signal presence/absence from R8 to line termination device
A circuit is provided to control whether or not to send the R8 signal to the line termination device depending on whether or not there is a need to send the signal, and when the RT double signal is not sent from the line termination device, the NS signal and the S
T, the signal transmission is suppressed, the DR double signal is being sent from the line termination device, and the R8 signal is being sent from the communication control device control unit.
This is achieved by a line adapter characterized in that it suppresses the transmission of the R8 signal except when all signal transmission is instructed.

(5) Embodiment of the invention FIG. 1 is a block diagram of one embodiment of the invention, and shows
5 is a Noritub 70 tube, 6.7 is an inverter, 8.9 is an AND circuit, 10.11 is a relay driver, 12.13 is a relay, 14 is a signal driver,
Reference numeral 15 represents a signal receiver, 9, A and B represent input signals, and aXb and c represent relay contacts. Input signal A is a signal that sets and resets the R8 signal, and input signal B is a signal that sets and resets the ER multiplication signal.
This is a signal that is controlled by the control program of the communication control device.

In Fig. 1, when the line adapter is connected to a line termination device (for example, a synchronous modem) that uses the RT double signal, the flip-flop 3 is set to receive the RT double signal from the line termination device, so the relay 13 does not operate and maintains the state shown in the figure, so the NS signal and ST1 signal are sent to the line termination device side through the relay contact or C.

When the line adapter is connected to a line termination device that does not use the RT double signal (for example, an asynchronous modem), the flip-flop 3 remains in the reset state because the RT double signal is not sent from the line termination device. Time is relay 1
3 is activated, relay contact bXc is opened, and the transmission of the NS and ST signals is inhibited.

On the other hand, in response to the ER double signal from the line adapter, if the line termination device side is operable, the DR notifies the ready state.
Since the double signal is sent back, these conditions are received by the AND circuit 9 and the shift flip-flop 5 is set by its output. Further, the output of the flip-flop 5 and the reset side output of the flip-flop 2 are input to an AND circuit 8,
Since the relay 12 is operated by the output of the AND circuit, the contact a of the relay 12 is opened and the transmission of the signal 8 is inhibited. However, when the input signal A arrives in this state, the flip-flop 2 is activated. Since it is set, the drive current to relay 12 is cut off and the R8 signal is sent through contact a' (i-).

By performing the above-mentioned control, the line adapter of this embodiment is of one type, and can be used as an asynchronous modem, a synchronous modem,
It is possible to support line termination devices with different control methods, such as CA16-NCU.

(6) Effects of the Invention As explained in detail above, one type of line adapter of the present invention can be used with various types of line termination devices, so it is not necessary to prepare dedicated ones for each type of line termination device as in the past. Since there is no system, design, management, etc. during product development and manufacturing are simplified, and there are advantages in terms of maintenance, which is very effective.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of one embodiment of the present invention. 1.2.3.4.5... Song flip-flop, 6.7.
Song/Inverter, 8.9...AND circuit, 10
．． 11... Relay driver, 12.13...
...Relay, 14...Signal driver, 15.
...Signal receiver

Claims (1)

[Claims] A line adapter that is located between the control unit of a communication control device and a line termination device and transfers signals, and is used to transfer NS and ST1 signals to the υ line termination device depending on the presence or absence of the RT double signal from the line termination device. A circuit that controls whether or not to send an ER signal to the line terminating device, the presence or absence of a DR double signal from the line terminating device in response to sending an ER signal to the line terminating device, and whether or not it is necessary to send an R8 signal to the line terminating device. A circuit for controlling whether or not to send the R8 signal is provided, and the R8 signal is sent from the line termination device.
When the T-fold signal is sent and there is no rice, the transmission of the NS signal and ST1 signal is suppressed, and when the DR-fold signal is being sent from the line termination equipment and the transmission of the R8 signal is instructed by the communication control unit control unit, the transmission of the R8 signal is suppressed. A line adapter characterized in that the transmission of an R8 signal is suppressed at times other than when the line adapter is in use.