JPH0336467B2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a data modulation/demodulation device used as a matching means for connecting a telephone line used for data transmission and various information processing devices or terminal devices, etc., and particularly to a mode setting device thereof. It is related to the method.

[Prior art]

With this type of data modulator/demodulator (acoustic coupler), for example, when performing full-duplex communication, one side receives an incoming call (1080±100Hz) with a low reception band (1080±100Hz) and a high transmission band (1750±100Hz). Data transmission between the data modulators and demodulators is performed by setting one device to the ANSWER mode and setting the other to the CALL mode in which the reception band is high and the transmission band is low. In this case, conventionally, both operators had a meeting over the phone or the like, and each set the mode manually based on the results of the meeting.

For this reason, there is a drawback that if either operator makes a mistake and sets each other to call origination or call reception mode, communication will not be possible. Also,
The disadvantage was that an expensive changeover switch was required to set the mode.

[Object and structure of the invention]

The present invention has been made in view of the above circumstances, and its purpose is to eliminate the labor required for mode setting, eliminate erroneous settings, and realize an inexpensive data modulation/demodulation device without a changeover switch. The object of the present invention is to provide a possible mode setting method for a data modem.

In order to achieve such an objective, the present invention
means for extracting a frequency signal arriving on a telephone line; an identification means for identifying the presence or absence and type of a receiving carrier from the extracted frequency signal; and setting to a predetermined mode among two modes in response to the identification result by the identification means. This means that there is a means to do so. Hereinafter, the present invention will be explained in detail using Examples.

〔Example〕

FIG. 1 is a block diagram showing one embodiment of the present invention. In the figure, reference numeral 10 denotes an acoustic coupling section consisting of a speaker 11 and a microphone 12, and a handset connected to a telephone line is set in this acoustic coupling section 10 for communication.

That is, the signal received from the receiver via the microphone 12 is filtered to remove noise components by the filter 20, demodulated by the modem 30, and transmitted via the interface section 40 to receive data.
Sent to the terminal device as RD. Furthermore, the transmission data SD sent from the terminal device is modulated by the modem 30, and sent via the amplifier 50 from the speaker 11 to the telephone line via the transmitter. Although omitted in the figure, 60 is a control circuit equipped with a well-known CPU, and is used to send and receive control signals to and from the terminal device via the interface section 40, for example, to receive a transmission request signal RS from the terminal device, and to receive the transmission request signal RS from the terminal device. It sends a send clear signal CS to the device and controls the transmission and reception of data to and from the telephone line. 61 is a carrier detection circuit,
A carrier is detected from the received signal and a carrier detection signal CD is sent to the terminal device. Reference numeral 62 denotes a gate circuit whose opening and closing are controlled by the output of the carrier detection circuit 61, and outputs an input clock pulse to the first counter 63. The output of the first counter 63 is sent to the filter 20 and the modem 30 and the second counter 64;
As will be described later, the output of No. 4 drives a buzzer circuit 65 that issues an alarm indicating that mode setting is not possible, and also resets the first counter 63.

Next, the operation of the above configuration will be explained in detail using FIGS. 2a and 2b and FIGS. 3a to 3e.

FIGS. 2a and 2b are flowcharts showing operations when transmitting and receiving data using the acoustic coupling device (data modulation/demodulation device) of this embodiment.

First, the handset is connected to the acoustic coupling section 10 described above.
(Step 1001). This turns on the power to the acoustic coupling device (step 1002).
Initialization is performed (step 1003).
At this time, the count value n of the second counter 64 is cleared to "0".

Here, the mode is temporarily set to calling mode (step 1004), and the presence or absence of a carrier is checked by the carrier detection circuit 61 (step 1005). At this time,
If a high group carrier is detected, it means that the other party is transmitting using a high group carrier, that is, it is set to incoming call mode, so the call mode is fixed as is (step 1006). , and thereafter perform normal communication. In other words, the carrier detection signal
Sends the CD (step 1007), receives data (step 1008), and sends the transmission request signal RS.
If it is detected (step 1009), a send enable signal CS is sent out (step 1010), and the transmission data sent from the terminal device is sent out to the telephone line (step 1011). This is repeated while the received carrier is detected (step 1012). If the transmission request signal RS is no longer detected, the transmission ready signal CS is stopped (step 1013), and in this case half-duplex communication is performed for reception only.

If the receiving carrier is no longer detected (step 1012), the transmission ready signal is stopped (step 1014), and the presence or absence of the transmission request signal RS is checked (step 1015). (Step 1016)
If there is a transmission request signal (step 1015,
1009), and sends out a transmission enable signal to perform data transmission (steps 1010 and 1011). That is, during this period, half-duplex communication is performed only for transmission.

On the other hand, in the detection of the receiving carrier after the provisional setting of the calling mode (step 1005), if a high group carrier is not detected, the predetermined time T1, e.g.
The low group carrier is sent out (step 1021) until a second has elapsed (step 1020), and after one second has elapsed, the incoming call mode is set (step 1022). T1=1
The seconds are provided to confirm the presence or absence of a received carrier, and are measured by the first counter 63.

That is, in FIGS. 3a to 3e, the first counter 63
This is a flowchart for explaining the operation of FIG. 3. When the power is turned on (FIG. 3a), a clock pulse b is input to the gate circuit 62 (FIG. 3b). At this time, while there is no received carrier and the output c of the carrier detection circuit is at the "H" level (Fig. 3c), the gate circuit 62 is in the open state, so the input clock pulse passes through the gate circuit 62 (see Figure 3c). 3d) Input to the first counter 63. The first counter 63 counts this input pulse, and sets its output e to the “H” level after one second has elapsed (the third
Figure e). This “H” level output is filter 2
0 and the modem 30, and the incoming call mode is set.

After setting the incoming call mode, the presence or absence of a receiving carrier (low group) is checked (step 1023), and if detected, it means that the other party is transmitting on a low group carrier, that is, the calling mode is set. Therefore, fix it to incoming call mode (step
1024) Transmit and receive data in the same manner as described above.

If the receiving carrier is not detected after setting the incoming call mode, the transmission of the carrier (high group) (step 1026) and the detection of the receiving carrier (low group) are performed until the predetermined time T2, for example, 2 seconds, has elapsed (step 1025). Step 1023) Repeat.

When the carrier is not detected and T2=2 seconds have elapsed, that is, the output of the first counter 63 becomes "L".
After returning to the level, it is determined whether or not the count value n of the second counter 64 exceeds a predetermined count value A, for example 20 (step 1027), and if it does not, the value of n is incremented by "1". (Step 1028) Temporary setting of call mode (Step 1004)
Repeat the above operations. If the received carrier is detected during that time, that is, the carrier detection circuit 6
1 turns to "L" (FIG. 3c), the gate circuit 62 is closed (FIG. 3d), and the output of the first counter 63 is fixed. In contrast,
When the value of n exceeds A=20, that is, the output of the first counter 63 repeats "L" for 1 second and "H" for 2 seconds as shown by the broken line in FIG.
2) If the mode cannot be fixed after x20=60 seconds have elapsed, it is determined that there is some kind of abnormality, and the buzzer is sounded to notify the operator of this fact (step 1030). In other words, when the count value n=20,
The output from the second counter 64 is transmitted to the buzzer circuit 65.
drive. At the same time, the first counter 63 is reset. It goes without saying that the buzzer circuit 65 may be replaced by a display device that provides some kind of visual display.

In this way, by detecting the presence or absence of a receiving carrier after temporarily setting the mode, fixing the mode according to the detection result, or temporarily resetting to another mode and repeating the same operation, mutually appropriate settings can be made. The mode will be set automatically.

In the above-described embodiment, the calling mode is first temporarily set, and then, if a receiving carrier is detected, the calling mode is fixed, whereas if the receiving carrier is not detected, the calling mode is provisionally set. In this case, if a receiving carrier is detected in that state, the mode is fixed to the incoming call mode, but first the incoming carrier mode is provisionally set, and if the receiving carrier (low group) is not detected, the mode is set again to the calling mode. Needless to say, you can do it this way.

An example in which the mode is set in the acoustic coupling device itself has been described above, but the mode may also be set by a control signal from a terminal device connected to the acoustic coupling device.

FIG. 4 is a block diagram showing an embodiment of the present invention in such a case. This embodiment is equipped with a keyboard and a display for people who make mistakes in speech, are hearing impaired, etc.
This is an example in which the present invention is applied to a text conversation device that enables text conversation using a telephone line, and includes a main body (terminal device) 100, an acoustic coupling device 2
00. The main body 100 includes a control unit 110 equipped with a well-known microprocessor, and a keyboard 1 equipped with character keys and various function keys.
20, a display section 130 consisting of a liquid crystal display panel, an AD conversion section 140 for converting a frequency signal arriving at a telephone line into a digital signal, and an acoustic coupling device 200 via an interface section 150;
is connected to. The acoustic coupling device 200 includes a control unit 210 equipped with a microprocessor, a microphone 220 for extracting frequency signals arriving at a telephone line, a speaker 230 for sending frequency signals to the telephone line, an amplifier 240, and a filter 250. , a modem 260, and is connected to the main body 100 via an interface section 270.

Here, from the amplifier 240 to the filter 250,
Interface unit 270 via modem 260
In addition to the normal received signal path to the amplifier 24
A telephone line status signal input line 280 is provided which extends directly from the telephone line 0 to the interface section 270, so that the frequency signal arriving at the telephone line can be taken out. The extracted signal is converted into a digital signal by the AD conversion section 140, and then sent to the control section 110 as described later.
identifies the state of the telephone line from the type and causes the display section 130 to display a predetermined guide.

That is, after the power is turned on, if a frequency signal (line status sound) arriving at the telephone line via the above-mentioned route is received as shown in FIG.
2001) First, the presence or absence of a 400Hz audible signal is checked (step 2002), and if it continues for 1 second or more (step 2003), it is determined that it is a dialable signal and a message to that effect is displayed on the display unit 130 (step 2002). 2004).

Even if there is an audible signal of 400 Hz, if it is not continuous for 1 second or more, it is further determined whether it is an intermittent sound with a duration of 0.5 seconds or less (step
2005), if the intermittent tone is present, a message indicating that the other party is busy is displayed (Step 2006), and if the above-mentioned intermittent tone is not, it is determined that it is a ringing tone (link back tone), and the message ``Calling'' is displayed. Do (step)
2007).

Also, if a 400Hz audible signal is not detected, the presence or absence of a receiving carrier, for example a high group receiving carrier, is detected (step 2008), and if detected, it means that the other party is transmitting a low group carrier. Since the incoming call mode is set, the control unit 110 controls the filter 2 via the control unit 210.
50 and modem 260, and set them to call mode (step 2009). Then, output the low group transmitting carrier (step
2010), and display that text conversation is possible (Step 2011). On the other hand, if a high number of receiving carriers are not detected, after waiting for the predetermined time T3 to elapse for confirmation (step 2020), a voice response is made, that is, if the other party is a text conversation device similar to this embodiment. It is determined that the phone is responding by voice as a normal phone call without using the phone, and a message to that effect is displayed (Step 2021).

On the other hand, if the line signal tone is not detected at first (step 2001), the system waits for the predetermined time T3 to elapse for confirmation (step 2001).
2030), determines that it is the called party, and sets the call receiving mode (step 2031). Then, the high group carrier is output (step 2032), and a display indicating that text conversation is possible is performed (step 2011).

After it is confirmed that both parties can have a text conversation, the text conversation is carried out with each other via the telephone line using input from the keyboard 120 and output to the display unit 130. That is, input data from the keyboard 120 is modulated by the modem 260 and sent to the telephone line via the speaker 230, and conversely, a signal received via the microphone 220 is demodulated by the modem 260, and the received message is displayed on the display. 130 is displayed on the display.

In this way, various guide messages are displayed on the display according to the state of the telephone line identified by the line signal tone extracted from the input line 280, so the operator can make a call with peace of mind by following the guide messages. be able to.

Here, the mode of the acoustic coupling device is the input line 2
80, the control unit 1
What is automatically set based on the judgment in 10.
This makes such a text conversation device even easier to use. This is true not only when applied to text conversation devices but also when applied to general data transmission.
This is especially useful for people with disabilities who have difficulty discussing setting modes over the phone in advance.

Note that in the above-described embodiment, it is of course possible to reverse the settings of the calling mode and the calling mode. That is, if the presence or absence of a low group reception carrier is detected, the mode may be set to the incoming call mode, and if no signal is detected, that is, if it is determined that the receiving carrier is on the receiving side, the mode may be set to the calling mode.

〔Effect of the invention〕

As explained above, according to the present invention, by providing means for detecting the presence or absence of a receiving carrier arriving at a telephone line, and means for setting a mode of a data modulation/demodulation device in accordance with the detection result, It is no longer necessary to manually set the mode as in the above, thereby eliminating setting errors and eliminating the need for a mode changeover switch, making it possible to realize an inexpensive data modulation/demodulation device.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing one embodiment of the present invention;
FIGS. 2a and 2b are flowcharts for explaining an example of its operation, FIGS. 3a to 3e are time charts, FIG. 4 is a block diagram showing another embodiment of the present invention, and FIG. It is a flowchart showing an example of operation. 10...Acoustic coupling unit, 11,230...Speaker, 12,220...Microphone, 20,25
0...Filter, 30,260...Modem, 4
0,150,270...Interface section, 6
0,120,210...Control unit, 61...Carrier detection circuit, 62...Gate circuit, 63,64...
... Counter, 65 ... Buzzer circuit, 100 ... Main body (terminal device), 140 ... AD conversion section, 200
...Acoustic coupling device, 280...Telephone line status signal input line.

Claims (1)

[Claims] 1. Modulating data from a connected terminal device in either a calling mode or an incoming call mode and transmitting the modulated data to a telephone line, and demodulating data from the telephone line and transmitting the data to the terminal device. The output data modulation/demodulation device includes means for extracting a frequency signal arriving at the telephone line, an identification means for identifying the presence or absence and type of a receiving carrier from the extracted frequency signal, and two corresponding to the identification result by this identification means. 1. A mode setting method for a data modulation/demodulation device, comprising: means for setting a predetermined mode among modes, and the mode is automatically set according to the presence or absence and type of a receiving carrier.