JPH0453337A - Communication equipment - Google Patents

Abstract

PURPOSE:To eliminate the need for the discrimination and the operation of the operator by discriminating the type of an opposite communication equipment with an input signal inputted from the communication opposite party via a connector so as to select the type of its own equipment automatically. CONSTITUTION:The equipment consists of a receiver 1, driver/receiver 2, 3, relays 5, 6, a relay control circuit 4, an RS 232C connector 7 and a serial control unit 8. Then the function of input and output terminals of the connector 7 is selected and set based on the result of detection of the input signal inputted via the connector 7. Thus, the communication is implemented in a different communication form from the opposite communication equipment.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a communication device that performs communication based on a standard such as an R3-232C interface.

[Prior Art] When performing communication using the R3-232C interface, it is necessary to determine in advance whether the other party's R3-232C format, data terminal equipment (hereinafter referred to as DTE), or data line termination equipment (hereinafter referred to as DCE). The connector must be connected according to the type of the other party.

Figure 3 (1) shows an example of connection between DTEs (hereinafter referred to as T-T connection), and Figure 3 (2) shows an example of connection between DTE and DCE (hereinafter referred to as M-■ connection). shows. As described above, in the past, the wiring configuration had to be changed depending on the model of the other party, which was inconvenient.

Also, communication devices have been put into practical use that can function as either DCE or DTE by switching a tip switch or the like depending on the model of the other party.

[Problem to be solved by the invention] In the above conventional technology, a straight cable must be used to connect the DCE and DTE (Figure 3 (2)).
, when communicating between DTEs, cross cables must be used. (Figure 3 (1)). Furthermore, even if one of the communication devices could function as either a DCE or a DTE, settings using the dip switch and the like had to be made by a human. Moreover, if the cable selection or the dip switch setting is incorrect, the input/output relationship of each terminal will be reversed, and there is a risk that the circuit elements may be destroyed.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above technical problems and provide a communication device that can detect the type of communication device of the other party and perform communication using different types.

[Means and effects for solving the problems] In order to achieve the above object, a communication device according to the present invention includes a connector having a plurality of input terminals, and a detection means for detecting an input signal inputted through the connector. and a switching means for switching and setting the function of the input/output terminal of the connector based on the detection output of the detection means.

According to the present invention, it is possible to determine the type of communication device of the communication partner (for example, DTE or DCE) based on an input signal input from the communication partner via a connector, and to automatically switch the type of the communication device of one's own device.

[Embodiment] Fig. 1 is a drawing that best represents the features of the present invention. In the figure, l is a receiver, 2.3 is a triver/receiver having the functions of a triver and a receiver, and 4 is a relay control circuit. The signal lines from pin 6 and pin 20 of the connector are connected through receiver l. 5゜6
The relay is controlled to open and close by the relay control circuit 4. 7
is an R3232C standard connector, and 8 is a serial control unit.

FIG. 2 shows the operation flow of the present invention, and the operation of this embodiment will be explained below. First, in the initial state, both relays 5 and 6 are in an open state (step Sl). When a signal is input to the relay control circuit 4 from either the 6th pin or the 20th pin of the connector, operation begins (step S2).

In the R3232C, there is a data set ready signal (DSR) that tells whether data can be transmitted or received from the DCE to the DTE, and this uses pin 6 of the connector. Conversely, pin 20 is used for the data terminal ready signal (DTR), which tells the DTE to the DCE whether transmission or reception is possible. Therefore, when communicating, a signal enters either the 6th pin or the 20th pin of this device, and the type of the other party's device (DTE or DCE) can be determined based on the pin number.

When an input signal is received from the 6th pin of the connector to the relay control circuit 4 (step S3), since the communication device of the other party is DCH, the relay control circuit 4 closes the relay 5 (step S4). Therefore, communication is carried out by serial control unit 8, driver/receiver 2. This is performed between relay 5 and connector 7 (step S5). This allows the communication device to function as a DTE. This connection is M-
It has a T connection. Relay control circuit 4 is connected to connector 6
If the input signal from the No. pin is no longer present (step S6), the process returns to step Sl and the relay 5 is opened.

In step S3, if the relay control circuit 4 receives an input signal from pin 20 of the connector, the other party is DTE.
Therefore, the relay control circuit 4 closes the relay 6 (
Step S7).

So communication is via serial control unit,
8: Performed between the driver/receiver 3 relays 6 connectors (step S8). This allows the communication device to function as a DCE. This connection is an M-T connection. When the input signal from the 20th pin of the connector disappears (step S9), the relay control circuit 4
), the process returns to step S1 and the relay 6 is opened.

In this way, in this embodiment, if the other party's communication device is a DTE, it functions as a DCE, and if it is a DCE, it automatically switches to function as a DTE, so human judgment and operation are not required. Did you explain the case where two communication devices or Stray 1 to Cable are connected?
Even if it is connected in a cross-scale manner (FIG. 3 (1)), the signal is input to the 6th bin, so it functions as a DTE (T-T connection).

[Effects of the Invention] As explained below, according to the present invention, communication can be performed in different communication formats depending on the communication device of the other party, etc., without performing any operation.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of the present invention, and FIG. 2 is a block diagram of an embodiment of the present invention.
Flowchart for explaining the operation of the illustrated embodiment. FIG. 3 is a diagram that does not show an example of the connection mode at the R3-232C interface. l is receiver 2.3 is l-lime/receiver 5.6 is relay 4 is relay control circuit 7 is connector for R3232C

Claims (1)

[Claims] (1) A connector having a plurality of input/output terminals, a detection means for detecting an input signal inputted through the connector, and switching the functions of the input/output terminals of the connector based on the detection result of the detection means. A communication device characterized in that it has a switching means for setting.