JP2001251443A - Communication terminal device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a communication terminal device which can continue a current telephone call even when a communication is started during the telephone call. SOLUTION: A codec part is switched to a telephone set side and when a given operation input indicating the start of a facsimile communication is done during a telephone call through the telephone set, the CODEC part is switched from the telephone set to a modem; when a document to be sent is set, G3 facsimile transmitting operation is performed and when not, G3 facsimile receiving operation is carried out by using the same B channel with the channel used for the telephone call through the telephone set. Then the CODEC part is switched back to the telephone set from the modem after the G3 facsimile transmitting or receiving operation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication terminal device such as a facsimile device, and more particularly, to a G4 through an ISDN.
While performing facsimile communication, a telephone or a modem is switched and connected to a codec unit for performing mutual conversion between analog signals and digital signals according to a predetermined rule, and a telephone call by the telephone via the ISDN or G3 by the modem. The present invention relates to a communication terminal device that performs facsimile communication.

[0002]

2. Description of the Related Art In a communication terminal device for performing communication via ISDN, a telephone call can also be performed.

[0003]

However, conventionally, ISD
If an attempt is made to make a communication during a call on N, the call is once terminated and a call is made to the same number, so that there was a problem that the call that had been made cannot be continued.

[0004] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a communication terminal device capable of continuing a call during a call even when the communication is activated during the call.

[0005]

According to a first aspect of the present invention, there is provided a communication terminal device for performing a G4 facsimile communication via an ISDN and a codec unit for performing mutual conversion between an analog signal and a digital signal according to a predetermined rule. Alternatively, in a communication terminal device for performing a G3 facsimile communication with the modem via the ISDN by switching connection of a modem, the connection of the codec unit is switched to the telephone side and a call with the telephone is performed. When there is a predetermined operation input for instructing the start of facsimile communication, the connection of the codec unit is switched from the telephone to the modem, and if a transmission original is set, G3 is set.
If a facsimile transmission operation is not performed, a G3 facsimile reception operation is performed using the same B channel used for the telephone call if the transmission original is not set, and the G3 facsimile transmission or reception operation is completed. And a communication start-up communication control unit for switching connection of the unit from the modem to the telephone.

According to a second aspect of the present invention, there is provided a communication terminal apparatus comprising:
While performing G4 facsimile communication via a telephone, a telephone or a modem is switched and connected to a codec unit for performing mutual conversion between an analog signal and a digital signal according to a predetermined rule, and a call by the telephone via the ISDN, or In a communication terminal device for performing G3 facsimile communication by the modem, when a predetermined operation input for instructing start of facsimile communication is performed during a call by the telephone by switching the connection of the codec unit to the telephone, a transmission original is transmitted. If is set, a call start communication control means for calling the same calling number as the current call destination and performing a G4 facsimile transmission operation using a B channel which is not currently used for the call by the telephone is provided. It is characterized by having.

According to a third aspect of the present invention, in the communication terminal device according to the second aspect, when the connection of the codec unit is switched to the telephone side and a G4 incoming call is detected during a telephone call by the telephone, A guidance message indicating whether or not to accept the incoming call is displayed, and if a response to accept is received, a G4 facsimile reception operation is performed using a B channel that is not currently used for the call, and a response to not accept is received. Is obtained, further comprising a call receiving control means for performing an operation of rejecting the G4 call when が is obtained.

According to a fourth aspect of the present invention, in the communication terminal device according to the second aspect, when the connection of the codec unit is switched to the telephone side and a G4 incoming call is detected during a telephone call by the telephone, Sending a voice message to the telephone as to whether or not to accept the incoming call,
If a response to the reception by a signal or a dial pulse is obtained, a G4 facsimile reception operation is performed using a B channel which is not currently used for a call, and DTMF is performed.
When a response indicating that the call is not accepted is obtained by a signal or a dial pulse, a call incoming call control means for rejecting a G4 call is further provided.

A communication terminal device according to a fifth aspect is an ISD
While performing G4 facsimile communication via N, a telephone or a modem is switched and connected to a codec unit which performs mutual conversion between analog signals and digital signals according to a predetermined rule, and a call by the telephone via the ISDN, or ,
In a communication terminal device that performs G3 facsimile communication by the modem, the connection of the codec unit is switched to the telephone side, and during a telephone call by the telephone, when there is a predetermined operation input for instructing the start of facsimile communication, When there is no vacancy in the B channel other than the B channel used for the telephone call, the connection of the codec unit is switched from the telephone to the modem,
The G3 facsimile transmission operation is performed when the transmission original is set, and the G3 facsimile transmission operation is performed when the transmission original is not set.
While performing the 3 facsimile reception operation using the same B channel used for the telephone call by the telephone,
When there is a vacancy in the B channel other than the B channel currently used for the telephone call by the telephone, if a transmission original is set, a call is made to the same calling number as that of the current call destination, and the call by the telephone is now made. A communication control unit for performing a G4 facsimile transmission operation using an unused B channel is provided.

[0010]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
An embodiment of the present invention will be described in detail.

First, FIG. 1 shows a block configuration of a communication terminal device 1 according to an embodiment of the present invention.

In FIG. 1, a system control unit 2 is a microcomputer that controls the entire communication terminal device 1. The system memory unit 3 is for storing information necessary for system control. The image memory unit 4 is for storing image information.

The encoding / decoding section 5 is for encoding and decoding image information. The recording unit 6 is for recording image information on recording paper. The reading section 7 is for reading original image information. The operation display unit 8 includes a display such as an LCD, and various operation keys such as numeric keys. As shown in FIG.
s] key 8b, [No] key 8c, and the like.

An I / O control unit 9 controls input / output ports in accordance with a command from the system control unit 2, and
1, for controlling / monitoring the status of the TEL interface unit 12.

The modem unit 10 converts a protocol signal and image information into V. 21, V.I. 34, V.I. 17, V.I. Modulation and demodulation in accordance with standards such as H.29, HDLC framing / deframing of data during protocol and ECM transmission / reception, C
It performs RC check or DTMF signal transmission, tone transmission and reception, and voice message signal transmission.

The communication analog unit 11 includes a modem unit 10, T
EL interface unit 12 or codec unit 14
For performing analog filter processing, switching of signal paths, and the like. TEL interface 1
Reference numeral 2 denotes an interface with the analog telephone 13.

The codec section 14 converts the analog signal to A / μ
The B-channel transmission control unit 15 for converting to PCM according to the rule is for transmitting image information as an HDLC frame on the B channel. The D channel transmission control unit 16 is for performing call control on the D channel. The layer 1 signal control section 17 is for matching each data of the D channel and the B channel with the layer 1 specification. The ISDN interface 18 is for interfacing with an ISDN digital line. The above components exchange data via the system bus 19.

FIG. 3 shows a block diagram of the communication analog 11 and the TEL interface unit 12.

In FIG. 1, a line transformer section 12a of a TEL interface section 12 is an analog telephone 1
The audio signal is transmitted by impedance matching with the signal 3 and is connected to the 2-wire to 4-wire conversion unit of the communication analog unit 11. The DC supply unit, ringing signal generation unit, and off-hook detection unit 12b supplies DC to the telephone, makes the telephone ring, and detects the off-hook or dial pulse of the telephone.

In the communication analog section 11, the 2-wire to 4-wire conversion section 11a includes a transmission / reception signal and a transmission signal TX / reception signal R.
It performs mutual conversion with X. Tone detector 11b
Is for detecting the frequency of the input signal, and is connected to the received signal RX between the modem unit 10 and the codec. The DTMF receiver 11c detects the number of the input DTMF signal.

SW1 is for switching the reception signal RX of the 2-wire / 4-wire conversion unit 11a to a reception signal RX (contact a side) or a transmission signal TX (contact b side) between the modem unit 10 and the codec unit 14. The contact is normally switched to the contact a side.

SW2 is the transmission signal T of the codec unit 14.
X is the transmission signal TX of the modem unit 10 (contact a side) or
The connection is switched to the transmission signal TX (contact b side) of the 2-wire-4 wire conversion unit 11a, and is always switched to the contact a side.

The SW3 connects the DTMF receiver 11c to:
A reception signal RX (contact point a side) between the modem unit 10 and the codec unit 14 or a transmission signal T of the two-wire to four-wire conversion unit 11a
The connection is switched to X (contact b side), and is always switched to the contact a side.

Next, a communication communication processing procedure in the facsimile apparatus according to the embodiment of the present invention in communication terminal apparatus 1 will be described with reference to FIGS.

First, in FIG.
Is a DC supply unit, a ringing signal generation unit, and an off-hook detection unit 1.
2b, the handset of the telephone 13 to which the DC voltage is constantly supplied is lifted, and it is monitored whether or not the off-hook of the telephone 13 is detected by the DC supply unit, the ringing signal generation unit, and the off-hook detection unit 12b (decision 101). When the off-hook of the telephone set 13 is detected (Yes in decision 101), SW1 is switched to the contact b side so that the reception signal RX of the telephone set 13 is transmitted to the modem unit 1.
It is connected to the transmission signal TX of 0 (process 102).

Then, a dial tone is transmitted from the modem unit 10 in the same manner as in the case where the local exchange is connected to the off-hook subscriber line (process 103). Also,
By switching SW2 to the contact b side, the telephone 13
Is connected to the transmission signal TX of the codec unit 14 (process 104). Further, by switching SW3 to the contact b side, the DTMF receiver 11c is connected to the transmission signal TX of the telephone 13 (process 105).

Then, according to the setting on the telephone 13 side, D
It is monitored whether the selection signal transmitted depending on the TMF signal or the dial pulse is detected by the DTMF receiver 11c or the off-hook detector 12b (decision 1).
When the first digit of the selection signal from the telephone is detected (No in step 06), the transmission of the dial tone started in step 103 is stopped (step 107).
By switching SW1 to the contact a side, the telephone 13
Is connected to the received signal RX of the codec unit 10 (process 108). In this case, the selection signal 2
The detection after the digit is continued.

Then, until the detection of the selection signal is completed,
The detection of the selection signal is continued (No in decision 109, processing 11
When the detection of the selection signal is completed (decision 10)
9 (Yes), the process moves to the process 201 in FIG.

In step 201 of FIG. 5, a call setting message is transmitted to the telephone number specified by the detected selection signal, and a predetermined call control procedure is performed (step 20).
1) The communication using one B channel is started (process 202).

After the process 202, the [Start] key 8b
Is pressed or an incoming call is detected, or the telephone 13
The call state is continued while monitoring whether or not the on-hook is detected (No in step 203, judgment 204, judgment 205).
No, No loop of judgment 206).

When the telephone 13 is on-hook without the [Start] key 8b being pressed and no incoming call during a telephone call with the telephone 13 (determination 2).
06, Yes), a call disconnection message is sent, the network is released, and the telephone call by the telephone set 13 is terminated. When the call is over, SW2 and SW3 are both returned to the initial state on the contact a side.

Instruction to start communication during a call [Start]
When the key 8b is depressed, the switch SW2 is switched to the contact a side, the switch SW3 is switched to the contact a side to return to the communication state (process 301), and the original is set by the original sensor (not shown) of the reading unit 7. Is determined (step 302).

If a document set is detected (Yes in decision 302), it is determined that a transmission document has been set, and the G3 transmission operation is terminated following the call on the B channel currently in use and being used. (Step 303,
When the G3 transmission operation is completed (No in decision 304), the flow proceeds to decision 307.

If the original set has not been detected (Yes in decision 302), it is determined that facsimile reception has been started, and the G3 receiving operation is terminated following the call on the currently used B channel during the call. Perform (Process 3
05, the No loop of the decision 306), when the G3 receiving operation is completed (Yes of the decision 306), the process proceeds to the decision 307.

In the judgment 307, it is judged whether or not the telephone 13 is still off-hook during the G3 transmission operation in the process 303 or after the G3 reception operation in the process 305 is completed (decision 307). (Yes in decision 307), switch SW2 to contact b side,
W3 is switched to the contact b side to return to the call state (step 308), and returns to step 203 to return to the call state.
If it is no longer off-hook (decision 307)
No), the processing shifts to the processing 207 in FIG. 5 to disconnect the call and release the network.

Thus, even if the communication is activated during the call and communication is performed, if the telephone 13 is still off-hook by the user who intends to continue the call after the communication is completed, the call can be continued. Can be.

If there is an incoming call during the communication in the judgment 205 in FIG. 5 (Yes in the judgment 205), the process 4 in FIG.
01, and G in B channel not used in the call
4 The receiving operation is started (process 401), and the process 20 in FIG.
Return to 3.

Of the above-described call communication processing procedures shown in FIGS. 4 to 7, when the determination 204 in FIG. 5 is Yes, the processing returns to the processing 203 in FIG. 5 after the end.
Instead of the processing procedure shown in FIG. 6, the processing procedure shown in FIG. 8 may be performed.

In FIG. 8, first, it is confirmed whether or not a B channel not used in a call during communication is in use by G4 transmission / reception (process 501), and when it is in use (Yes in decision 502). , The message "communicating" is displayed on the display 8a for a certain period of time, and the user is informed that communication using a B channel other than the B channel used for the active call cannot be started. The process is notified and the process ends, and the process returns to the process 203 in FIG.

If it is determined in step 502 that the document is not being used (No in step 502), it is determined whether a document is set in the reading unit 7 (step 504). (No in decision 504), no operation is performed in order to wait for an incoming call from the other party, and a preparation is made for a G4 reception operation by processing 401 in FIG.

If the original is set (judgment 5
04, Yes), the G4 transmission operation using the vacant B channel not used in the active call is started (process 505), the process ends, and the process returns to process 203 in FIG.

Thus, even if the communication is activated during the call and the communication is performed, the call during the call can be continued without interruption.

4, 5, 7 and 8 are performed when the determination 205 in FIG. 5 is Yes, and after the end, the process returns to the process 203 in FIG. Instead of the processing procedure shown in FIG. 7, the processing procedure shown in FIG. 9 may be performed.

In FIG. 9, first, a display 8a is displayed on the display 8a.
As shown in the display D01 of 0, a guidance display of “There is an incoming call.
1) It is monitored whether the [Yes] key 8b or the [No] key 8c is pressed (No in the judgment 602, a No loop in the judgment 603), and when the [No] key 8c is pressed (the judgment 603). Yes), the process ends, and the process 2 in FIG.
Return to 03.

When the [Yes] key 8b is pressed (Yes in decision 602), the G4 receiving operation is started on the B channel not used in the call (process 401), and the process returns to process 203 in FIG. .

As described above, when an incoming call is received, the user does not unconditionally respond to the incoming call, but through the user's judgment. Whether to use a B channel other than the B channel used for the call, which is likely to be used, for communication activated during the call, or for a G4 reception operation in response to an incoming call Can be selected by the user, and a flexible response in accordance with the priority considered by the user is possible.

In the call communication processing procedures of FIGS. 4, 5, 7, and 8, the processing is performed when the determination 205 of FIG. 5 is Yes, and after the end, returns to the processing 203 of FIG. Instead of the processing procedure shown in FIG. 7, the processing procedure shown in FIG. 11 may be performed.

In FIG. 9, first, SW1 is connected to the modem 1
0 is switched to the transmission signal TX side (contact b side), and a voice message saying “There is an incoming call. Would you like to receive it?” Is sent from the modem unit 10 (process 701). By pressing the numeric key of the handset, the DTMF is set according to the setting of the telephone 12 side.
An operation of notifying a number as a selection signal by a signal or a dial pulse is performed.

In response to this, it is monitored whether or not the selection signal is detected by the DTMF receiver 11c or the off-hook detection unit 12b (decision 702). When the selection signal is detected (Yes in decision 702), the selection signal is identified by the number " It is determined whether the number indicates "2" or the number "0" (determination 703, determination 704). If the number indicates "0" (Yes in determination 704), the process is terminated. Finished, Figure 5
The process returns to step 203.

If the number indicates "2",
The G4 receiving operation is started on the B channel not used in the call (process 705), and the process returns to process 203 in FIG.

As described above, when an incoming call is received, the user does not unconditionally respond to the incoming call but through the user's judgment. B used for calls that may be used
The user can select whether to save a B channel other than a channel for communication activated during a call or to use the B channel for a G4 receiving operation in response to an incoming call. Flexible response is possible. Further, transmission of a voice message to the telephone 13 and the telephone 1
Since it is possible to receive the user's determination as to whether or not to respond to the incoming call by the selection signal from the terminal 3, the user's determination can be reliably received even when the telephone 13 is far from the communication terminal device 1.

Of the communication communication processing procedures of FIGS. 4 to 7 described above, the processing is performed when the determination 204 of FIG. 5 is Yes, and after the end, returns to the processing 203 of FIG.
Instead of the procedure shown in FIG. 6, the procedure shown in FIG. 12 may be performed.

In FIG. 12, first, it is confirmed whether or not a B channel not used in a call in use is in use by G4 transmission / reception (process 801). If it is in use (Yes in decision 802). Then, the processing shifts to judgment 805.

If it is determined in step 802 that the document is not in use (No in step 802), it is determined whether a document is set on the reading unit 7 (step 803). (No in step 803), the process returns to step 203 in FIG. 5 without performing any operation to wait for an incoming call from the other party, and prepares for the G4 reception operation in step 401 in FIG.

If a document is set (judgment 8
03, Yes), the G4 transmission operation using the vacant B channel not used in the active call is started (process 804), the process ends, and the process returns to process 203 in FIG.

If the determination in step 802 is Yes, a determination is made in step 805 whether or not a document is set on the reading unit 7 (step 805). If no document is set (No in step 805) 5), the process returns to step 203 in FIG. 5 without performing any operation to wait for an incoming call from the other party, and prepares for the G4 reception operation in step 401 in FIG.

If a document is set (judgment 8
05, Yes), the display 8a shows the display D1 shown in FIG.
0 is displayed and the B channel other than the B channel used in the call cannot be used due to the communication, so the B channel currently used for the call is used for the communication by interrupting the call. Prompts the user to determine whether

Then, the [Yes] key 8b or the [N
o] key 8c is monitored for depression (N in decision 807)
o, No loop of the judgment 808), when the [No] key 8c is pressed (Yes of the judgment 808), the processing is ended and the processing returns to the processing 203 of FIG.

If the [Yes] key 8b is pressed (Yes in decision 808), the processing shifts to processing 301 in FIG. 6, and the processing procedure in FIG. 6, which is a communication procedure using the B channel during a call, is performed. Then, according to the determination 307, the processing shifts to the processing 203 of FIG. 5 or the processing 207 of FIG.

Thus, when communication is activated during a call, if there is a vacant B channel in addition to the B channel used for the call, the vacant B channel is used without interruption of the call. If the user can start communication and want to suspend the call and use it for communication even if there is no free B channel, the B channel used for the call is temporarily The communication can be performed by interrupting the call and used for communication, and the call can be returned after the communication ends. It should be noted that, after Yes in decision 802 in FIG.
It is also possible to omit the process of asking the user of steps 05 through 808 and automatically proceed to the process 301 of FIG. 6, in which case the activation of the communication activated during the call without user intervention is performed. Control can be performed.

As described above, according to the present embodiment, even when communication is activated during a call, the activated communication can be performed while continuing the call during the call.

[0062]

According to the first aspect of the present invention, when the start of communication is started during a call by the telephone, communication can be performed by switching the connection destination of the codec unit from the telephone to the modem, and the communication ends. Thereafter, since the connection destination of the codec unit can be returned from the modem to the telephone so that the telephone call can be continued, even when the communication is activated during the telephone call, the telephone call during the telephone call can be continued. Is obtained.

According to the second aspect of the present invention, when the communication start is started during the telephone call by the telephone, the communication is performed by using the vacant B channel which is not used for the telephone call. Calls and communications can be performed at the same time without interrupting the call during the call temporarily by the communication activated in
Even when the communication is activated during the call, the effect that the call during the call can be continued can be obtained. In addition, since high-speed communication (64 kbps) in G4 can be performed, there is an advantage that the communication time can be shortened.

According to the third aspect of the present invention, the communication is started during the call to answer or reject the answer according to the judgment of the user during the call without unconditionally responding to the incoming call of the communication during the call. If so, an effect is obtained in which the communication to be activated can be prioritized.

According to the fourth aspect of the present invention, the communication is started during the call to answer or reject the call according to the judgment of the user during the call without unconditionally responding to the incoming call of the communication during the call. If so, an effect is obtained in which the communication to be activated can be prioritized. Further, a notification of an incoming call of a communication during a call is performed by sending a voice message to the telephone, and an instruction from a user as to whether or not to accept the incoming call is received by a DTMF signal or a dial pulse. And it is possible to reduce the number of operation errors caused by overlooking the guidance.

According to the fifth aspect of the present invention, if there is a vacant B channel that is not used for a call, communication is performed using the B channel. Calls and communications can be performed at the same time without temporary interruption of the current call.
Communication speed (64 kbps) can be performed, so that the communication time is short. In addition, a vacant B not used for calls
Even if there is no channel, communication can be performed by switching the connection destination of the codec unit from the telephone to the modem, and after communication is completed, the connection destination of the codec unit is returned from the modem to the telephone to continue the call. Can be. Therefore, even when the communication is activated during the call, the effect that the call during the call can be continued as long as possible without any judgment by the user is obtained.

[Brief description of the drawings]

FIG. 1 is a diagram showing a block configuration of a communication terminal device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a partial configuration of an operation display unit of the facsimile apparatus according to the embodiment of the present invention.

FIG. 3 is a diagram showing a block configuration and the like of a communication analog unit of the facsimile apparatus according to the embodiment of the present invention.

FIG. 4 is a flowchart showing a call communication processing procedure in the facsimile apparatus according to the embodiment of the present invention.

FIG. 5 is a flowchart showing a call communication processing procedure in the facsimile apparatus according to the embodiment of the present invention.

FIG. 6 is a flowchart showing a call communication processing procedure in the facsimile apparatus according to the embodiment of the present invention.

FIG. 7 is a flowchart showing a call communication processing procedure in the facsimile apparatus according to the embodiment of the present invention.

FIG. 8 is a flowchart showing a call communication processing procedure in the facsimile apparatus according to the embodiment of the present invention.

FIG. 9 is a flowchart showing a call communication processing procedure in the facsimile apparatus according to the embodiment of the present invention.

FIG. 10 is a diagram illustrating an example of guidance display in the processing procedure of FIG. 9;

FIG. 11 is a flowchart showing a call communication processing procedure in the facsimile apparatus according to the embodiment of the present invention.

FIG. 12 is a flowchart showing a call communication processing procedure in the facsimile apparatus according to the embodiment of the present invention.

FIG. 13 is a diagram showing an example of guidance display in the processing procedure of FIG.

[Explanation of symbols]

 Reference Signs List 1 communication terminal device 2 system control unit 3 system memory unit 4 image memory unit 5 encoding / decoding unit 6 recording unit 7 reading unit 8 operation display unit 8a display unit 8b [Yes] key 8c [No] key 9 I / O control Unit 10 Modem unit 11 Communication analog unit 11a 2-wire to 4-wire conversion unit 11b Tone detection unit 11c DTMF receiver unit 12 TEL interface unit 12a Line transformer unit 12b DC supply / ringing signal generation / off-hook detection unit 13 Telephone 14 Codec unit 15B Channel transmission control unit 16 D-channel transmission control unit 17 Layer 1 signal control unit 18 ISDN interface unit 19 System bus SW1, SW2, SW3 Switch

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5C062 AA03 AA12 AA34 AB46 AC27 AC39 AC40 AC42 AC58 AE07 AE11 AF02 AF03 5C075 AB03 AB08 BA03 BB14 CD25 FF04 FF90 5K101 KK01 LL03 PP07 QQ02 QQ08 QQ13

Claims (5)

[Claims] 1. While performing G4 facsimile communication via ISDN, a telephone or a modem is switched and connected to a codec unit for performing mutual conversion between an analog signal and a digital signal according to a predetermined rule. In a communication terminal device for performing a telephone call or a G3 facsimile communication using the modem, there is a predetermined operation input for instructing a start of facsimile communication during a telephone call by switching the connection of the codec unit to the telephone. Switch the connection of the codec section from the telephone to the modem, and use the G3 facsimile transmission operation if the transmission original is set, and use the G3 facsimile reception operation if the transmission original is not set for the telephone call. The same B that was doing
A communication terminal device comprising a communication start-up communication control unit that performs communication using a channel and switches connection of the codec unit from the modem to the telephone after a G3 facsimile transmission or reception operation is completed. 2. While performing G4 facsimile communication via ISDN, a telephone or a modem is switched and connected to a codec unit for performing mutual conversion between an analog signal and a digital signal according to a predetermined rule. In a communication terminal device for performing a telephone call or a G3 facsimile communication using the modem, a predetermined operation input for instructing a start of facsimile communication during a telephone call by switching the connection of the codec unit to the telephone. In the case where the original is set and a call is made to the same calling number as the current call destination and a G4 facsimile transmission operation is performed using a B channel which is not currently used for the telephone call, A communication terminal device comprising start communication control means. 3. When the connection of the codec unit is switched to the telephone side and a G4 incoming call is detected during a telephone conversation by the telephone, a guidance message indicating whether or not the incoming call is to be accepted is displayed, and a response to the acceptance is received. If it is obtained, a G4 facsimile reception operation is performed using a B channel which is not currently used for a call, and if a response of rejection is obtained, a call reception control means for performing a G4 call rejection operation is provided. The communication terminal device according to claim 2, further comprising: 4. When a G4 incoming call is detected during a telephone call by switching the connection of the codec unit to the telephone side, a voice message as to whether or not to accept the incoming call is sent to the telephone, and a DTMF signal is transmitted. Alternatively, if a response indicating that the call is to be accepted by a dial pulse is obtained, a G4 facsimile reception operation is performed using a B channel that is not currently used for a call, and a response indicating that the call is not accepted by a DTMF signal or a dial pulse is obtained. 3. The communication terminal device according to claim 2, further comprising a call incoming call control unit that performs a G4 incoming call rejection operation in a case. 5. While performing G4 facsimile communication via ISDN, a telephone or a modem is switched and connected to a codec section for performing mutual conversion between an analog signal and a digital signal according to a predetermined rule. In a communication terminal device for performing a telephone call or a G3 facsimile communication using the modem, a predetermined operation input for instructing a start of facsimile communication during a telephone call by switching the connection of the codec unit to the telephone. In this case, when there is no available B channel other than the B channel currently used for the telephone call, the connection of the codec unit is switched from the telephone to the modem, and when the transmission original is set, G3 facsimile transmission operation when the transmission original is not set While the G3 facsimile receiving operation is performed using the same B channel used for the telephone call, if there is a free B channel other than the B channel currently used for the telephone call, If the transmission original is set, a call is made to the same calling number as that of the current call destination, and G4 is used using the B channel which is not currently used for the telephone call.
A communication terminal device comprising: a communication start-up communication control unit that performs a facsimile transmission operation.