JP3673752B2 - Facsimile communication apparatus and facsimile communication method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a facsimile communication apparatus, particularly an ITU-T recommendation V.30. The present invention relates to a facsimile communication apparatus and a facsimile communication method capable of eight communications.
[0002]
[Prior art]
In 1994, ITU-T recommended V. 8 is established. It is conceivable to apply the procedure specified in 8 to a facsimile apparatus.
[0003]
This V. A facsimile machine to which the procedure according to No. 8 is applied is described in V. A facsimile apparatus that supports the procedure defined in 34 and image transmission is targeted.
[0004]
Here, V. 8, Although there is a description of 17, communication is not clearly determined.
[0005]
[Problems to be solved by the invention]
However, the transmitter is 34 communication is supported, and an ANSam signal is received from the receiver when a call is made. When a CM signal designating 34 communication is transmitted, V.24 is transmitted from the receiver. 17 when the JM signal instructed to be communicated by the terminal 17 is received. 8 Communication procedures are not clearly determined. Therefore, V.V. 8 After performing communication, It is a DIS signal of 21 signals. 8 When there is a reception function and when a CI signal is transmitted, 17 There is a problem that communication may not be established.
[0006]
In the present invention, the transmitter is a V.D. 34 communication is supported, and an ANSam signal is received from the receiver when a call is made. When a CM signal designating 34 communication is transmitted, V.24 is transmitted from the receiver. An object of the present invention is to provide a facsimile communication apparatus and a facsimile communication method capable of shortening the communication time when a JM signal instructed for communication at 17 is received.
[0007]
[Means for Solving the Problems]
The present invention relates to an ITU-T recommendation V. ANSam signal receiving means for receiving an ANSam signal in a facsimile communication apparatus that executes a procedure defined in FIG. 8 and sets an image transmission mode that can be executed with the counterpart apparatus based on the procedure, and a CM CM signal transmitting means for transmitting a signal, and after receiving the ANSam signal, V. 34, a CM signal designating communication is transmitted, and the V. 34 When a JM signal that cannot be communicated is received, a CJ signal is transmitted, and V.40 is transmitted from the other receiver. 21 when the DIS signal of 21 is received. After executing the protocol No. 21 and receiving the ANSam signal, 34, a CM signal designating communication is transmitted. 8 The above V. When the DIS signal of 21 is received for the first time, the CI signal is transmitted. 34, a CM signal designating communication is transmitted. 8 The above V. The next time the DIS signal of 21 is received, 8 Even if the reception function is provided, the process does not shift to the transmission of the CI signal. And a control means for executing 21 protocols.
In addition, the present invention relates to ITU-T recommendation V. 8 is a facsimile communication method for setting an image transmission mode executable with the counterpart device based on the above procedure, and an ANSam signal receiving step for receiving an ANSam signal; CM signal transmission stage for transmitting a signal, and after receiving the ANSam signal, 34, a CM signal designating communication is transmitted, and the V. 34 When a JM signal that cannot be communicated is received, a CJ signal is transmitted, and V.40 is transmitted from the other receiver. 21 when the DIS signal of 21 is received. After executing the protocol No. 21 and receiving the ANSam signal, 34, a CM signal designating communication is transmitted. 8 The above V. When the DIS signal of 21 is received for the first time, the CI signal is transmitted. 34, a CM signal designating communication is transmitted. 8 The above V. The next time the DIS signal of 21 is received, 8 Even if the reception function is provided, the process does not shift to the transmission of the CI signal. And a control step of executing 21 protocols.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
First, the V.C. The procedure signal No. 8 will be described.
[0009]
V. The procedure signal 8 includes a call menu signal (hereinafter referred to as “CM”), a CM end terminal (hereinafter referred to as “CJ”), and a common menu signal (hereinafter referred to as “JM”). Yes.
[0010]
The signal CM is a signal transmitted from the calling DCE, and this signal CM is mainly used for displaying a modulation scheme available in the calling DEC. The signal CM is a recommendation V.3. The low frequency channel V.21 defined in FIG. It is composed of a repetitive bit string of 300 bits / s modulated by 21 (L).
[0011]
The signal CJ is a signal indicating the confirmation that JM has been detected and the end of CM. The signal CJ is a 300 bit / s V.V. It is modulated by 21 (L) and is composed of three consecutive “0” octets including a start bit / s and a stop bit / s.
[0012]
The signal JM is a signal transmitted from the response DEC, and this signal is mainly used to indicate an available modulation scheme common to the call origination and the response DEC. The signal JM is the recommendation V. High-frequency channel V.21 defined in FIG. It is composed of a repetitive bit string of 300 bits / s modulated by 21 (H).
[0013]
Next, the encoding format of each signal of CM, CJ, and JM will be described.
[0014]
FIG. FIG. 10 is a diagram illustrating a configuration of a preamble included in 8 procedure signals.
[0015]
A common encoding format is used for the signals CM, CJ, and JM, and each signal CM, CJ, and JM is composed of a repeated bit sequence. As shown in FIG. 7, one sequence is composed of octets carrying 10 “1” s first, followed by a 10-bit synchronization code, and further information. In each octet, a preceding start bit (“0”) and a subsequent stop bit (“1”) are added.
[0016]
The same V. is applied to the signal JM. Recommendation T.21 using 21 (H) modulation. In order to avoid confusion with 30, a code constraint condition is imposed on the bit arrangement so that the HDLC flag (01111110) never appears.
[0017]
Each octet belongs to a certain information category. This coding format allows the information category to be extended for a particular application, provided that the simplicity of the signal is preserved by the majority of applications.
[0018]
The first information category in a sequence must be a calling function. Among the information categories that follow, no particular order is defined. All information in a category is conveyed in one octet or, if necessary, in an ordered octet sequence.
[0019]
Next, category octets will be described.
[0020]
FIG. It is a figure which shows the form of the category octet which determines the information category of 8 procedure signals.
[0021]
The category octet is the first octet generated in a new information category, and this octet includes a 4-bit code that determines the information category.
[0022]
This format is configured as follows, and the displayed bits are transmitted in order from left to right.
[0023]
Start bit (0) b0 b1 b2 0 1 0 b6 b7 Stop bit (1)
As shown in FIG. 8, bits b0 to b3 form a category having b0 as the least significant bit, and bit b4 is set to “0” so that the flag is not established. Further, b5 to b7 are information category option bits.
[0024]
If three option bits are insufficient to represent a particular category, any number of extended octets can follow immediately after the category octet.
[0025]
The format of this extended octet is configured as shown below.
[0026]
Start bit (0) b0 b1 b2 0 1 0 b6 b7 Stop bit (1)
Bits b0 to b2, b6, and b7 are five bits added to the category at that time. Bit b4 is set to “1” in order to distinguish the extended octet from the category octet, and b3 and b5 are set to “0” so that the flag is not satisfied.
[0027]
Next, the calling function, modulation mode, protocol, and GSTN access, which are information categories determined by bits b0 to b3, will be described.
[0028]
FIG. 9 is a diagram illustrating a usage example of the bits of the calling function octet.
[0029]
The three option bits in the calling function octet are used to specify a particular calling function, as shown in FIG.
[0030]
FIG. 10 shows ITU-T recommendation V.10. FIG. 9 is a diagram illustrating a modulation mode designated by a procedure signal 8.
[0031]
As shown in FIG. 10, V series modulation modes usable in GSTN are designated by three codes. The availability setting is limited to the displayed call function when the modulation mode is available and it is desired to communicate the capability to the remote DCE.
[0032]
FIG. 11 shows ITU-T recommendation V.10. 9 is a diagram illustrating a code list inside a protocol category of a procedure signal in FIG.
[0033]
A list of codes within the protocol category is shown in FIG. If the LAPM protocol code is indicated by CM and the response DCE side that has received it wants to use LAPM as well, the protocol octet for displaying LAPM is also displayed in JM.
[0034]
FIG. 12 shows ITU-T recommendation V.12. It is a figure showing the code | symbol which shows the cellular access connected to GSTN in the procedure signal of 8. FIG.
[0035]
The code indicating the cellular access connected to the GSTN is shown in FIG.
[0036]
Next, V. The information bits of INFO0 specified in 34 will be described.
[0037]
FIG. 13 shows the V.I. It is a figure which shows the bit definition of 34 INFO0 sequences.
[0038]
INFO0 is a signal used to indicate the transmission capability, and the bits of the signal sequence are defined as shown in FIG.
[0039]
In this embodiment, INFO0a is a signal transmitted from the called side, and INFO0c is a signal transmitted from the calling side.
[0040]
Next, a first embodiment of the present invention will be described.
[0041]
FIG. 1 is a block diagram showing the configuration of a facsimile apparatus FS1 according to the first embodiment of the present invention.
[0042]
The facsimile machine FS1 includes a network control unit (hereinafter referred to as NCU) 2 connected to a telephone line 2a. The NCU 2 performs connection control of the telephone exchange network such as connection to a line terminal for using the telephone network for data communication, switching to the data communication path, connection between the telephone line 2a and the telephone 4, and telephone line The connection between 2a and the hybrid circuit 6 is selectively switched.
[0043]
The NCU 2 and the telephone 4 are connected by a signal line 2b, and the NCU 2 and the hybrid circuit 6 are connected by a signal line 2c. The switching operation of the NCU 2 is controlled by a control circuit 20 described later. When the control signal supplied from the control circuit 20 via the signal line 20a is “0”, the telephone line 2a and the telephone 4 are connected. On the other hand, when the control signal is “1”, the telephone line 2 a and the hybrid circuit 6 are connected. In the normal state, the connection between the telephone line 2a and the telephone 4 is selected.
[0044]
The hybrid circuit 6 separates a transmission signal from the transmission system transmitted via the telephone line 2a and a reception signal to the reception system received via the telephone line 2a.
[0045]
The transmission system includes an image sensor such as a CCD (electrically coupled device), a reading circuit 14 including an optical system, and an ANSam transmission circuit 10.
[0046]
The reading circuit 14 sequentially reads an image for one line in the main scanning direction from the transmission original, and data indicating the read image is output to the signal line 14a.
[0047]
The ANSam sending circuit 10 outputs an ANSam signal to the signal line 10a when a signal of level “1” is given from the control circuit 20 via the signal line 20d. On the other hand, when a signal of level “0” is given from the control circuit 20 via the signal line 20d, the ANSam signal is not output to the signal line 10a.
[0048]
Data output from the reading circuit 14 via the signal line 14 a is given to the control circuit 20. The control circuit 20 encodes the data captured via the signal line 14a, and the encoded data is output to the modem 8 via the signal line 20b.
[0049]
The modem 8 modulates the encoded data from the signal line 20b to generate a modulated signal, and also demodulates the received signal received from the hybrid circuit 6 via the signal line 6a to obtain demodulated data. Is generated. The modulation process and the demodulation process are ITU-T recommendation V. 8, V. 21, V.R. 27ter, V.I. 29, V.R. 17, V. 34. The contents of the modulation and demodulation processing by the modem 8 are instructed by a signal given from the control circuit 20 via the signal line 20c, and the transmission mode is determined by the instructed modulation and demodulation processing.
[0050]
The modulation signal generated by the modem 8 is given to the adder circuit 12 through the signal line 8a. The adder circuit 12 adds the modulation signal from the modulator / demodulator 8 and the ANSam signal from the ANSam transmission circuit 10. The added signal is output to the hybrid circuit 6 via the signal line 12a, and the hybrid circuit 6 sends the added signal to the telephone line 2a via the NCU 2 as a transmission signal.
[0051]
On the other hand, in the receiving system, a signal received from the counterpart device via the NCU 2 is output from the hybrid circuit 6 to the modem 8 via the signal line 6a. As described above, the modem 8 demodulates the received signal received via the signal line 6a to generate demodulated data. The demodulated data generated by the modem 8 is given to the control circuit 20 via the signal line 8b. The control circuit 20 performs a process such as decoding the demodulated data, and the decoded data is given to the recording circuit 16 via the signal line 20e.
[0052]
The recording circuit 16 sequentially records the image indicated by the decoded data on a recording sheet line by line.
[0053]
Data read by the reading circuit 14, data obtained by encoding the data, received data, and data obtained by decoding the data are stored in the memory circuit 18 as necessary.
[0054]
The control circuit 20 receives information from the counterpart device and performs transmission control for transmitting information to the counterpart device.
[0055]
The transmission control procedure for defining this transmission control includes ITU-T Recommendation V.3. 8, V. 21, V.R. 27ter, V.I. 29, V.R. 17, V. 34 procedures are used.
[0056]
Specifically, the ITU-T recommendation V. 8 is a facsimile communication apparatus that executes an image transmission mode that can be executed with the counterpart device based on the procedure defined in FIG. 8, and has an ANSam signal receiving unit and a CM signal transmitting unit. After receiving the ANSam signal, V. 34 A CM signal designating communication is transmitted, and V. 34, when the JM signal that cannot be communicated is received, the CJ signal is transmitted, and V.40 is transmitted from the other receiver. When the DIS signal of 21 is received, V. 21 protocols are executed.
[0057]
Here, V.V. When the DIS signal of 21 is received, 8 Even if the reception function is provided, the process does not shift to the transmission of the CI signal. 21 protocols are executed.
[0058]
On the other hand, after receiving the ANSam signal, V. 34 A CM signal designating communication is transmitted, and V. When a JM signal capable of 34 communication is received, a CJ signal is transmitted. When the DIS signal of 21 is received, 8 The subsequent protocol is changed depending on the presence or absence of the reception function. Specifically, V.D. If there is an 8 reception function, a CI signal is transmitted. 8 If there is no reception function, V. 21 protocols are executed.
[0059]
2, 3 and 4 are flowcharts showing the control operation of the embodiment shown in FIG.
[0060]
In step S2, a signal of level “0” is output to the signal line 20a and the CML is turned off. In step S4, a signal of level “0” is output to the signal line 20d so that the ANSam signal is not output. In step S6, 0 is set in the path FLG.
[0061]
Next, step S8 is executed. In step S8, it is determined whether or not a call is selected. If a call is not selected, step S10 is executed, and if a call is selected, step S11 is executed.
[0062]
In step S10, other processing is executed, and after the other processing is executed, the processing returns to step S2.
[0063]
In step S11, a signal of level “1” is output to the signal line 20a and CML is turned on. In step S12, a calling circuit is used to call a designated destination. In step S13, an ANSam signal is sent. Receive.
[0064]
In step S14, V.P. 21, V.R. 27ter, V.I. 29 half duplex, V.E. 17, V. A CM signal designating 34 half-duplex communication is transmitted, and in step S16, the timer is set to 6 seconds.
[0065]
In step S18, V.P. It is determined whether or not the DIS signal of 21 is received. If the DIS signal of 21 is received, the process proceeds to step S42 and V.21 is received. If the DIS signal of 21 is not received, the process proceeds to step S20.
[0066]
In step S20, V.P. 8 determines whether or not a JM signal of 8 has been received. If the JM signal of 8 is received, the process proceeds to step S24, where If the 8 JM signal is not received, the process proceeds to step S22.
[0067]
In step S22, it is determined whether or not the timer has expired. If the timer has expired, the process proceeds to step S2, and if the timer has not expired, the process proceeds to step S18.
[0068]
In step S24, a determination is made based on the received JM signal. 34 determines whether or not half duplex communication is possible. If half-duplex communication of 34 is possible, the process proceeds to step S26. If 34 half-duplex communication is not possible, the process proceeds to step S38.
[0069]
In step S26, V.P. 34 transmits a CJ signal designating half-duplex communication. It is determined whether or not a DIS signal with 21 signals has been received. If the DIS signal with the 21 signal is received, the process proceeds to step S32, where If the DIS signal with 21 signals is not received, the process proceeds to step S30.
[0070]
In step S30, INFO0c is transmitted. 34 shows execution of image transmission.
[0071]
In step S32, the received V.P. Judging from the DIS signal of 21 signals, 8 is determined whether or not there is a reception function. If there is a reception function of No. 8, the process proceeds to step S34, where If there is no 8 reception function, the process proceeds to step S36.
[0072]
In step S34, V.P. 8 CI signals are transmitted. In step S36, the V.V. 21 signal NSS / TSI / DCS signal is transmitted. 21. V. 27ter, or V.I. 29, or V.I. 17 image transmission is executed. 17 A CJ signal designated for communication is transmitted.
[0073]
In step S40, the V.V. It is determined whether the NSF / CSI / DIS signal with the 21 signal is received or not. If an NSF / CSI / DIS signal with 21 signals has been received, the process proceeds to step S36 (in this case, it is important to proceed to S36 regardless of the presence or absence of the V.8 reception function included in the DIS signal) V.). If the 21 signal NSF / CSI / DIS signal is not received, the process proceeds to step S2.
[0074]
In step S42, it is determined whether or not the path FLG is 0. If the path FLG is 0, the process proceeds to step S44, 1 is set in the path FLG, and if the path FLG is not 0, the process proceeds to step S36. .
[0075]
Next, the transmission control procedure will be described.
[0076]
FIG. 5 is a diagram showing an example of a transmission control procedure applied to the facsimile apparatus FS1.
[0077]
FIG. 6 is a diagram showing another example of the transmission control procedure applied to the facsimile apparatus FS1.
[0078]
First, a V.30 based on the ANSam signal received from the called terminal. The transmission control procedure up to the execution of step 34 and image transmission will be described.
[0079]
In FIG. 5, a signal (an ANSam signal, which is 2100 Hz modulated by 15 Hz) enabling full duplex communication is transmitted from the called terminal. From the calling side, V.D. A CM signal by modulation based on 8 is transmitted, and a transmission mode that can be executed at the time of image transmission is notified to the called terminal by this CM signal.
[0080]
The called terminal that has received the CM signal notifies the calling terminal of a transmission mode (V.34) that can be received among the transmission modes specified by the CM signal, and the JM signal is used for this notification.
[0081]
The calling terminal that has received the JM signal notifies the called terminal of the transmission mode by sending a CJ signal.
[0082]
After sending the CJ signal, After 50 msec have elapsed after the completion of 8 procedures, the calling terminal The execution of the 34 procedure is started, and a line probing signal (INFO0c is added to the head) for checking the status of the telephone line 2a is transmitted.
[0083]
The called terminal sends a signal in response to the line probing signal from the calling terminal (INFO 0a is added at the head), and the sending terminal corrects the subsequent transmission level, amplitude level, and transmission baud rate by this signal. Notify
[0084]
The calling terminal sends a long training signal after 50 msec has passed since the line probing signal has been sent, and the called terminal performs modem equalizer adjustment, timing detection, etc. based on this long training signal To do.
[0085]
The calling terminal sends a parameter exchange signal after 50 msec has elapsed after sending the long training signal. The called terminal sends a signal in response to the parameter exchange signal, and notifies the calling terminal of the subsequent link correction and bit rate by this signal.
[0086]
After responding to the parameter exchange signal, the called terminal sends a CSI and DIS signal, sends a flag until receiving a TSI and DCS signal from the calling terminal, receives a TSI and DCS signal, and then receives a CFR signal. Is sent out. The calling terminal sends the TSI and DCS signals after receiving the CSI and DIS signals, and sends a flag until receiving the CFR signal from the called terminal.
[0087]
The calling terminal transmits the V.V. after 50 msec has elapsed since the flag was sent. 34 starts image transmission and transmits an image signal. V. After 50 msec from the end of image signal transmission, V. 34 is executed, a PPS-MPS signal is transmitted from the calling terminal, and a flag is transmitted until an MCF signal from the called terminal is received. The called terminal sends an MCF signal after receiving the PPS-MPS signal.
[0088]
V. 50 msec after sending the flag, 34 is executed, and the image signal is sent again from the calling terminal. V. After 50 msec from the end of image signal transmission, V. Step 34 is executed, and the calling terminal sends a PPS-EOP signal and sends a flag until it receives an MCF signal. The called terminal transmits the MCF signal after receiving the PPS-EOP signal. Thereafter, the same procedure is repeated until the image transmission is completed.
[0089]
Next, from reception of the ANSam signal from the called terminal, V. 21. V. A transmission control procedure up to execution of 17 image transmission will be described.
[0090]
In FIG. 6, first, the called terminal transmits ANSam, and the calling terminal 34 A communicable CM signal is transmitted. At this time, the receiver receives V. 17 Transmits a communicable JM signal. Based on the reception of the JM signal, the calling terminal receives the V.V. 17 A CJ signal designating communication is transmitted. Subsequently, if the called terminal is V.D. 21 NSF / CSI / DIS signals are transmitted. The calling terminal transmits the V.V. of the received DIS signal. 8 V. Regardless of the presence or absence of the reception function. 21 TSI / DCS signals are transmitted. 21 procedures; 27ter, or V.I. 29, or V.I. Execute 17-screen transmission.
[0091]
In FIG. If the 34 communication is designated, the received V.V. 21 with the DIS signal. 8 If there is no reception function, V. 21 shifts to the transmission of the TSI / DCS signal. 21 with the DIS signal. If there is 8 reception function, V. 8 to transmit the CI signal, and again receives the ANSam signal. 34 Try to execute communication.
[0092]
According to the above embodiment, the transmitter is a V.V. 34 communication is supported, and an ANSam signal is received from the receiver when a call is made. When a CM signal specifying 34 communication is transmitted, When a JM signal instructed for communication at the time 17 is received from the receiver, 8 After executing communication, It is a DIS signal of 21 signals. 8 With reception function, V. 21 DCS signals are transmitted to ensure V. 17 communication, while the other receiver receives V.17 communication. When a JM signal capable of 34 communication is received, a CJ signal is transmitted. When the DIS signal of 21 is received, If there is an 8 reception function, a CI signal is transmitted. Since 34 communications can be executed, the communication time can be shortened.
[0093]
【The invention's effect】
According to the invention, the transmitter is a V.V. 34 communication is supported, and an ANSam signal is received from the receiver when a call is made. When a CM signal designating 34 communication is transmitted, V.24 is transmitted from the receiver. The communication time can be shortened when a JM signal instructed for communication at 17 is received.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of a facsimile machine FS1 according to a first embodiment of the present invention.
FIG. 2 is a flowchart showing a control operation of the embodiment shown in FIG.
FIG. 3 is a flowchart showing a control operation of the embodiment shown in FIG. 1;
4 is a flowchart showing a control operation of the embodiment shown in FIG.
FIG. 5 is a diagram illustrating an example of a transmission control procedure applied to the facsimile apparatus FS1.
FIG. 6 is a diagram showing another example of a transmission control procedure applied to the facsimile apparatus FS1.
FIG. 7: ITU-T recommendation V. FIG. 10 is a diagram illustrating a configuration of a preamble included in 8 procedure signals.
FIG. 8: ITU-T recommendation V. It is a figure which shows the form of the category octet which determines the information category of 8 procedure signals.
FIG. 9 is a diagram illustrating a usage example of a bit of a calling function octet.
FIG. 10: ITU-T recommendation V. FIG. 9 is a diagram illustrating a modulation mode designated by a procedure signal 8.
FIG. 11: ITU-T recommendation V. 9 is a diagram illustrating a code list inside a protocol category of a procedure signal in FIG.
FIG. 12: ITU-T recommendation V. It is a figure showing the code | symbol which shows the cellular access connected to GSTN in the procedure signal of 8. FIG.
FIG. 13 is a diagram of V.100 according to ITU-T recommendation. It is a figure which shows the bit definition of 34 INFO0 sequences.
[Explanation of symbols]
FS1 ... facsimile machine,
4 ... Telephone,
10 ... ANSam circuit,
14: reading circuit,
16 ... Recording circuit,
18 ... Memory circuit,
20: Control circuit.

Claims (2)

ITU-T recommendation V. between the counterpart device. In the facsimile communication apparatus that executes the procedure defined in FIG. 8 and sets an image transmission mode that can be executed with the counterpart apparatus based on the above procedure,
ANSam signal receiving means for receiving the ANSam signal;
CM signal transmitting means for transmitting a CM signal;
After receiving the ANSam signal, V. 34, a CM signal designating communication is transmitted, and the V. 34 When a JM signal that cannot be communicated is received, a CJ signal is transmitted, and V.40 is transmitted from the other receiver. 21 when the DIS signal of 21 is received. After executing the protocol No. 21 and receiving the ANSam signal, 34, a CM signal designating communication is transmitted. 8 The above V. When the DIS signal of 21 is received for the first time, the CI signal is transmitted. 34, a CM signal designating communication is transmitted. 8 The above V. The next time the DIS signal of 21 is received, 8 Even if the reception function is provided, the process does not shift to the transmission of the CI signal. Control means for executing 21 protocols ;
A facsimile communication apparatus comprising: ITU-T recommendation V. between the counterpart device. 8, a facsimile communication method for setting an image transmission mode executable with the counterpart device based on the procedure described above,
Receiving an ANSam signal; receiving an ANSam signal;
A CM signal transmission stage for transmitting the CM signal;
After receiving the ANSam signal, V. 34, a CM signal designating communication is transmitted, and the V. 34 When a JM signal that cannot be communicated is received, a CJ signal is transmitted, and V.40 is transmitted from the other receiver. 21 when the DIS signal of 21 is received. After executing the protocol No. 21 and receiving the ANSam signal, 34, a CM signal designating communication is transmitted. 8 The above V. When the DIS signal of 21 is received for the first time, the CI signal is transmitted. 34, a CM signal designating communication is transmitted. 8 The above V. The next time the DIS signal of 21 is received, 8 Even if the reception function is provided, the process does not shift to the transmission of the CI signal. A control phase implementing 21 protocols ;
A facsimile communication method characterized by comprising:

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