JPH0723077A - Intelligent modem - Google Patents

Abstract

PURPOSE:To provide an intelligent MODEM in which a V.25 bis command can be used without being limited by a communicating environment at a data terminal equipment (DET) side. CONSTITUTION:This device is equipped with a communicating environment setting part 14 which sets a communication mode emvironment at the time of operating communication with the opposite party DTE and a command mode environment at the time of transmitting and receiving a command/ indication with a DTE 20 connected to its own device. The communication mode environment is made to correspond to a character format matching the communication environment of the opposite party DTE, and the command mode environment can be arbitrarity selected from either of the fixed information of '7 bit' and 'Even parity' and the character format at the time of the communication mode. Thus, the switching of a serial port at the DTE side can be unncessitated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intelligent modem controlled by CCITT (International Telegraph and Telephone Consultative Committee) Recommendation V.25bis command.

[0002]

2. Description of the Related Art Various commands such as a personal computer or a data terminal equipment (hereinafter referred to as DTE) can be used to perform various communication controls such as automatic transmission and automatic call reception. An intelligent modem having an automatic identification function is known. CCITT Recommendation V.25 is one of the command systems for controlling the communication mode of this kind of intelligent modem.
There is bis. This V.25bis defines the following three methods for controlling an intelligent modem.

(1) Asynchronous command / indication (2) BSC command / indication (3) HDLC command / indication In the above control methods, "command" refers to general commands from the DTE to the modem side. "Indication" refers to a response from the modem side to the DTE.

Among them, in the control method of the asynchronous command / indication, the character format is "7bi" mainly in consideration of use in the alphabet.
t "and" Even parity ".

[0005]

However, in Japan, which is a non-alphabet, the shift JIS code composed of 2 bytes (8 bits × 2), which is one unit of the Kanji code, is frequently used. Communication is often "without parity". Therefore, when the conventional intelligent modem is used, the DTE must change the setting of the serial port between the command mode and the communication mode. That is, "7 bit" and "Even parity" in the command mode of issuing a command to the modem / receiving an indication from the modem, and "8 bit" and "no parity" in the communication mode of communicating with the other side DTE. "2
It was necessary to switch between different character formats, and the processing procedure (communication software, etc.) had to be complicated.

Further, for example, most communication software for personal computer communication (network communication using a general-purpose personal computer or a word processor and a modem) "performs command / indication and communication with the partner DTE in the same character format". Like this,
The switching itself becomes impossible.

[0007] Further, some communication software for business use "correctly complies with V.25bis, performs command / indication with 7 bits and even parity, and the other side DTE.
Communication is performed according to the other party (for example, 8 bits, without parity). However, in this case, it becomes impossible to operate with the conventional intelligent modem in which "the command / indication and the communication with the partner DTE are performed in the same character format".

The present invention has been made under such a background, and an object thereof is any DTE utilizing V.25bis asynchronous command / indication.
It is to provide an intelligent modem that can also support.

[0009]

The structure of the present invention which achieves the above object is controlled by the procedure according to CCITT Recommendation V.25bis and is connected to the communication mode for communicating with the DTE on the other side. In the intelligent modem having a command mode for transmitting and receiving commands and indications to and from the DTE, the other side DT
A first memory for storing first character format information predetermined according to the communication environment of E;
a second memory for storing second character format information, for example, in asynchronous operation defined in bis,
And a setting means for setting the first character format information in the communication mode and selectively setting the first or second character format information in the command mode. There is.

[0010]

In the intelligent modem of the present invention, the first character format information is determined in advance according to the communication environment of the DTE on the other side and stored in the first memory. Further, the second character format information in the asynchronous operation of CCITT recommendation V.25bis is stored in the second memory. Then, the setting means sets the character format information according to the current mode. For example,
In the communication mode, the communication environment based on the first character format information is set, while in the command mode, the communication environment based on the first or second character format information is selectively set. This eliminates the need to switch the character format on the controlling DTE side.

[0011]

Embodiments of the present invention will now be described with reference to the drawings.

FIG. 1 is a connection configuration diagram of an embodiment of the present invention. 10 is an intelligent modem, 11 is an interface setting unit, 12 and 13 are memories, 14 is a communication environment setting unit, and 15 is an intelligent processing unit. . 20 is D
TE, which is connected to the intelligent modem 10 via a transmission cable. Further, this intelligent modem 10 is connected to the other party D (not shown) via a communication line.
It is connected to a TE (modem).

The intelligent modem 10 of this embodiment will be described as being controlled by the above-mentioned asynchronous command / indication.

The interface setting unit 11 sets the character format information according to the current mode, and specifically, does not show the selective reading function of different character format information stored in advance in the memories 12 and 13. It can be set by DIP-SW.

For example, when the modem 10 is in the communication mode, the memory 1 is previously set in accordance with the communication environment of the DTE on the other side.
“8 bit” and “non parity” (first character format information) stored in 2 are read out,
When in command mode, the same character format information as in communication mode or CCITT Recommendation V.
Either one of the fixed information of "7 bit" and "Even parity" (second character format information) according to 25 bis is selectively read.

The first character format information is not necessarily limited to that corresponding to the shift JIS code, and may be arbitrarily selected from a plurality of character formats.

In the communication environment setting unit 14, each memory 12,
The above-mentioned character format information read from 13 is registered on the communication environment table. As a result, subsequent communication or command / indication will be performed according to this registration information. The setting and registration of the character format information can be performed by a command directly sent from the DTE 20 as well as by the DIP-SW.

The intelligent processing unit 15 performs normal intelligent processing, automatic transmission and automatic call reception, and automatic identification of communication speed and communication standard according to the communication environment set by the communication environment setting unit 14.

In the intelligent modem 10 having the above configuration, for example, the communication software used in the DTE 20 is
If "command / indication and communication with partner DTE are performed using shift JIS code", both communication mode environment and command mode environment of communication environment setting unit 14 are registered as "8 bit" and "non parity". To do. Also, "correctly according to V.25bis, command / indication is" 7bit "and" Eve ".
In the case of commercial communication software that uses "n-parity" to communicate with the DTE of the other party according to the other party using shift JIS code, the communication mode environment of the communication environment setting unit 14 is "8bi
"t" and "non parity" are registered, and the command mode environment is registered with "7 bit" and "Even parity". Furthermore, if any DTE complies with V.25bis, both the communication mode environment and the command mode environment are registered with "7 bit" and "Even parity".

In this way, the DT connected to itself is
The E20 side does not need to change the setting of the serial port between the command transmission and the data communication, and the load of the communication software is remarkably reduced. Therefore, data communication and command / indication transmission / reception can be performed without being restricted by the communication environment of each DTE, and the conventional problems can be solved.

Although the present embodiment is as described above, the present invention is not limited to the above embodiment, and the configuration can be changed without departing from the scope of the invention.

[0022]

As is apparent from the above description, according to the present invention, it is not necessary to switch the serial port and the communication environment setting on the DTE side. Therefore, the CCITT recommendation V.25bis asynchronous command / indicator is not required. It is possible to provide an intelligent modem capable of supporting any DTE utilizing the application.

[Brief description of drawings]

FIG. 1 is a configuration diagram of essential parts of an intelligent modem according to an embodiment of the present invention.

[Explanation of symbols]

 10 ... Intelligent modem 11 ... Interface setting unit 12, 13 ... Memory 14 ... Communication environment setting unit 15 ... Intelligent processing unit

Claims (2)

[Claims] 1. A communication mode in which communication is performed with a counterpart data terminal device, controlled by a procedure according to CCITT Recommendation V.25bis, and transmission and reception of commands and indications with a data terminal device connected to itself. In the intelligent modem having a command mode for performing the above, a first memory for storing first character format information predetermined according to the communication environment of the other party's data terminal device, and the V.25bis standard. A second memory for storing second character format information, and setting the first character format information when in the communication mode, and the first or second character format information when in the command mode And a setting means for selectively setting Event modem. 2. The second character format is
2. The intelligent modem according to claim 1, wherein the intelligent modem has a character format for asynchronous operation defined by V.25bis.