JP2802188B2 - Modem - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a modem connected between a portable telephone having a communication port defined as RS-232C and a data terminal.

[0002]

2. Description of the Related Art When data communication is performed, a data terminal device that transmits and receives data in accordance with communication regulations is connected to a telephone line via a modem and a telephone. If the place is a destination,
The modem is connected to a telephone line via a mobile phone. Therefore, in order to automate the communication at this time, it is necessary to cause the data terminal device to control the mobile phone in addition to the control of the modem.

There are two methods for realizing this control. One of them is to use a data terminal device having two RS-232C communication ports, and to use the data terminal device with a modem and a mobile phone respectively. This is a method of controlling the modem and the mobile phone by using a data terminal device by adopting a connected configuration.

Another one is two RS-232Cs.
Control using a modem equipped with a communication port, with a data terminal connected to one of the communication ports of the modem and a mobile phone connected to the other, and transmitted from the data terminal to the modem. Split the code into two sets of control codes. In this method, one set of control codes is used for controlling the modem, and the other set of control codes is a code for controlling the mobile phone via the modem.

[0005]

SUMMARY OF THE INVENTION The above two RS-2s
The configuration using a data terminal device provided with a 32C communication port has a single communication port when a portable computer, which is lightweight and miniaturized for portability, is used for the data terminal device. For this reason, there has been a problem that both the modem and the mobile phone cannot be connected to the data terminal device.

[0006] Further, in a configuration in which a modulation / demodulation device having two sets of RS-232C communication ports is used and a mobile phone is controlled via the modulation / demodulation device, the control code is divided into two sets of code groups. In the communication between the device and the data terminal device, both the control code related to the modem and the control code related to the mobile phone are mixed, and the identification of the control code is complicated.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a modem capable of preventing a control code from becoming complicated and an increase in the number of communication ports of a data terminal device. It is in.

[0008]

In order to solve the above-mentioned problems, a portable telephone control system according to the present invention comprises a first RS-23.
A TXD signal transmitted from the data terminal device is applied to a modem connected to the mobile phone via the 2C communication line and connected to the data terminal device via the second RS-232C communication line, TX sent to mobile phone
D signal or an input signal to the modulation / demodulation unit main body is switched, and the switching operation is performed by the first RS-232C.
A TXD signal switching unit controlled by a control signal transmitted from a mobile phone via a communication line, and a first RS-23
The switching operation is controlled by a control signal transmitted from the mobile phone via the 2C communication line, and a signal transmitted from the modem unit or R transmitted from the mobile phone is controlled.
An XD signal is switched so as to output the signal, and the switching output is used as an RXD signal to the data terminal device.
XD signal switching unit, and the second RS-23
Via a 2C communication line and a first RS-232C communication line,
A control signal transmitted from the data terminal device to the mobile phone is used to instruct the mobile phone to perform control.

[0009]

The second RS-232C communication line and the first RS-2
The mobile phone to which the control instruction is given by the control signal transmitted from the data terminal device via the 32C communication line transmits the control signal via the first RS-232C communication line, and The connection between the signal switching unit and the RXD signal switching unit is on the mobile phone side. In this state, the mobile phone receives control from the data terminal device.

Further, when the control is completed, the connection between the TXD signal switching section and the RXD signal switching section is made on the modulation / demodulation section main body side, so that the data terminal device, the modulation / demodulation section main body, and the mobile phone are connected in series.

[0011]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing an electrical configuration of an embodiment of the present invention.

In the figure, a data terminal device 15 and a modulation / demodulation device 13 are connected to a TXD signal TXD2 and an RXD signal RXD2 as signal lines for data, a DSR signal DSR2 and a DTR signal DTR2 as signal lines for control. They are connected to each other via a second RS-232C communication line 12 including a signal CI2 and a ground line SG2 for digital signals.

The modem 13 and the portable telephone 14 are connected to a TXD signal TXD1, which is a signal line for data.
RXD signal RXD1, DSR which is a signal line for control
Signal DSR1, DTR signal DTR1, CI signal CI1,
Ground line SG1 for digital signal, analog signal ASD
1, ARD1, and a ground line ASG1 for analog signals
Are connected to each other via a first RS-232C communication line 11 consisting of

TXD signal TX from data terminal device 15
D2 is connected to the contact c of the TXD signal switching unit 21 and the contact a is guided to the modem unit main body 23. Also T
The contact b of the XD signal switching unit 21 is introduced to the control unit 34 of the mobile phone 14 as a TXD signal TXD1.

An RXD signal RXD1 sent from the control unit 34 is connected to a contact b of the RXD signal switching unit 22, and an output from the modem unit 23 is guided to a contact a. The contact c of the RXD signal switching unit 22 is connected to R
It is introduced to the data terminal device 15 as an XD signal RXD2.

The DSR signal DS sent from the control unit 34
R1 is a TXD signal switching unit 21 and an RXD signal switching unit 22
, And are grounded via a resistor R. Also, the DSR signal DSR1 is DS
It is transmitted to the data terminal device 15 as an R signal DSR2.

DTR signal DT from data terminal device 15
R2 is supplied to the control unit 34 as a DTR signal DTR1, and the ground line SG2 is guided to the modem unit main body 23 and is also introduced to the control unit 34 as a ground line SG1. Further, a pair of inputs of the OR gate 24 includes a control unit 3
4 and an output from the modulation / demodulation unit main body 23, and the output of the OR gate 24 is provided to the data terminal device 15 as a CI signal CI2.

The analog signal ASD1 output from the modulation / demodulation unit main body 23 is guided to a contact a of a switch S11. The contact c of the switch S11 is connected to a modulation unit 31 for transmitting the guided analog signal as radio waves. ing. The output from the microphone 35 is guided to the contact b of the switch S11.

The output of the demodulation unit 32 for demodulating the received radio wave is introduced to the contact c of the switch S12, and the contact b is guided to the speaker 36. Switch S12
The contact a is guided to the modem unit main body 23 as an analog signal ARD1.

The output from the control unit 34 is guided to both the switches S11 and S12 as a switching control signal, and the control signal from the control unit 34 is introduced to the modulation unit 31 and the demodulation unit 32. Have been. The output from the antenna 33 is guided to the demodulation unit 32, and the output from the modulation unit 31 is sent to the antenna 33.

In the above configuration, the modem 13 is
The mobile phone 14 includes a TXD signal switching unit 21, an RXD signal switching unit 22, a modem unit 23, an OR gate 24, and a resistor R.
1, S12, modulation section 31, demodulation section 32, antenna 33,
The control unit 34 includes a microphone 35 and a speaker 36.

The TXD signal switching section 21 and the RXD signal switching section 22 are constituted by digital multiplexers, and the switches S11 and S12 are constituted by analog multiplexers.

The control signals transmitted from the portable telephone 14 and controlling the TXD signal switching unit 21 and the control signals for switching the RXD signal switching unit 22 are as follows: In the present embodiment, both of them are DSR signals DSR1 of a plurality of control signals of the first RS-232C communication line 11.

FIG. 2 is a timing chart showing the timing of main signals according to one embodiment of the present invention. The operation of one embodiment of the present invention having the above-described configuration will be described below with reference to FIG.

When data communication starts (time T1)
1), the data terminal device 15 sets the DTR signal DTR2 to H
By setting the level to H11 and setting the DTR signal DTR1 to the H level, the control unit 34 is instructed that the data to be transmitted is a control code.

At time T12, the control unit 34 given this instruction sets the DSR signal DSR1 to the H level H12 and sets the DSR signal DSR2 to the H level, thereby entering the control mode M11 in which the control code is received. This is notified to the data terminal device 15.

At this time, the TXD signal switching section 21 and R
Since DSR signal DSR1 attains the H level, XD signal switching unit 22 connects each c contact to each b contact, and outputs TXD signal TXD from data terminal device 15.
2 is guided to the control unit 34 as a TXD signal TXD1. The RXD signal RXD1 from the control unit 34 is RXD
The signal is transmitted to the data terminal device 15 as the D signal RXD2.

On the other hand, the data terminal device 15, to which the H level H12 has been guided, transmits a control code C11 for instructing off-hook as a first control for calling, as a TXD signal TXD2.
This control code C11 is transmitted to the TXD
It is provided to control unit 34 as signal TXD1.

The control unit 34 sets the operation state to off-hook, and sends a response code C12 indicating that the operation state is off-hook to the RXD signal RXD1, and outputs the RXD signal RXD.
This is given to the data terminal device 15 as D2. Next, when a control code C13 indicating the number of the other party is transmitted from the data terminal device 15 to the control unit 34, the control unit 34
Performs dialing and sends to the data terminal device 15 a response code C14 indicating that dialing has been performed.

When receiving the response code C14, the data terminal device 15 determines that the control of the portable telephone 14 has been completed, and indicates the end of the control.
The signal DTR2 is set to L level.

For this reason, the control unit 34 sets the DTR signal DTR
1 at the time T14 corresponding to the L level of
By setting the SR signal DSR1 to L level, it is notified that the operation mode has shifted from the control mode M11 to the data mode M12, and the TXD signal switching unit 21, RX
Each c contact of the D signal switching unit 22 is connected to each a contact. Further, the control unit 34 performs control to connect the respective c contacts of the switches S11 and S12 to the respective a contacts.

When the L level is transmitted to the DSR signal DSR2, the data terminal device 15 transmits the TXD signal TXD2 to the modem unit 23 to connect the internal modem to the cellular phone 14. The control code C15 to be instructed is transmitted.

For this reason, the modem unit 23 connects the modem to the portable telephone 14 and, when the partner device responds, responds with a response code C indicating that the connection has been completed.
16 is sent to the RXD signal RXD2, and the operation mode is shifted from the control mode M13 to the data mode M14.

Response code C via RXD signal RXD2
The data terminal device 15 to which the data terminal 16 has been guided determines that the preparation for data transmission has been completed.
Data communication with the modem unit 23 is started via the XD signal TXD2 and the RXD signal RXD2.

Therefore, the data D11 from the data terminal device 15 guided to the modem unit 23 via the TXD signal TXD2 is transmitted to the modulation unit 31 as an analog signal A11. An analog signal A12 indicating data from the partner device side is an RXD signal RXD as data D12.
The data is output from the modulation / demodulation unit main body 23 to the data terminal device 15 via the communication terminal 2. That is, data communication is performed.

When the communication is completed, the data terminal device 15 transmits the DTR signal DT similarly to the operation at the time of calling.
R2 is set to the H level, and the DSR signal DSR is
After waiting for the H level to be sent to the control unit 1, the control code indicating the end of the communication is sent to the control unit 34. Therefore, the control unit 34 sends a control code indicating that the end instruction has been received to the RXD signal RXD1, sets the state to the on-hook state, and sets each of the switches c11 and S12 to c.
Control is performed to connect a contact to each b contact.

The operation at the time of making a call has been described above. When there is an incoming call from the partner device, an output indicating the incoming call is output from the CI.
Indicated by the H level transmitted to the signal CI1 (when the destination is a facsimile and a facsimile-specific calling signal is transmitted, the modem unit 23 outputs an OR signal.
The H level is output to the output sent to the gate 24). Therefore, the data terminal device 15 outputs the CI signal CI2
Becomes H level, there is an incoming call, and an operation corresponding to the incoming call is performed.

It should be noted that the present invention is not limited to the above embodiment, and the control signal has been described in the case where the DSR signal DSR1 is used as the control signal among the plurality of control signals of the first RS-232C communication line 11. However, it is possible to adopt a configuration in which another signal is used for the control signal.

The control signal guided to each of the TXD signal switching section 21 and the RXD signal switching section 22 has been described assuming that both are DSR signals DSR1.
Both control signals include the first RS-232C communication line 11
Of the two control signals, one of which is TXD
The control signal of the signal switching unit 21 and the other is the RXD signal switching unit 2
A configuration using two control signals is possible.

[0041]

According to the portable telephone control system of the present invention, a TX whose operation is controlled by a control signal transmitted from the portable telephone via the first RS-232C communication line is provided.
Using the D signal switching unit, the TXD signal transmitted from the data terminal device is switched to the TXD signal to the mobile phone or the input signal to the modem unit,
Using an RXD signal switching unit, the operation of which is controlled by a control signal transmitted from a mobile phone via an RS-232C communication line, a signal transmitted from the modem unit or an RXD signal transmitted from the mobile phone The output is switched, and the switched output is used as an RXD signal transmitted to the data terminal device. The second RS-
The control signal transmitted from the data terminal device to the mobile phone through the H.232C communication line and the first RS-232C communication line instructs the mobile phone to perform control. Only one communication port is required, and control codes are separately sent to the modem and the mobile phone. Therefore, the control code becomes complicated and the number of communication ports of the data terminal increases. This can provide an effect that both can be prevented.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an electrical configuration of an embodiment of the present invention.

FIG. 2 is a timing chart showing timings of main signals according to one embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 1st RS-232C communication line 12 2nd RS-232C communication line 13 Modulator / demodulator 14 Cellular phone 15 Data terminal device 21 TXD signal switching unit 22 RXD signal switching unit 23 Modulation / demodulation unit main body TXD1 TXD signal TXD2 TXD signal RXD1 RXD Signal RXD2 RXD signal

Claims (1)

(57) [Claims] 1. A modem connected to a mobile phone via a first RS-232C communication line and connected to a data terminal device via a second RS-232C communication line. The TXD signal sent from the terminal device is switched to the TXD signal sent to the mobile phone or the input signal to the modem unit, and the switching operation is performed via the first RS-232C communication line. TXD controlled by a control signal sent from the mobile phone
The switching operation is controlled by a signal switching unit and a control signal transmitted from the mobile phone via the first RS-232C communication line, and a signal transmitted from the modem unit or transmitted from the mobile phone. And an RXD signal switching unit for switching the RXD signal to an output of the data terminal device and for setting the switching output to an RXD signal to the data terminal device, wherein a second RS-232C communication line and a first RS-232C A modulation / demodulation device, wherein a control signal transmitted from the data terminal device to the mobile phone via a communication line instructs the mobile phone to perform control.