JPH11215260A - Communication equipment, reception control method and storage medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow communication equipment having a function for a dial-in call to surely and correctly receive a signal sent directly from an exchange in the case of receiving a dial-in call. SOLUTION: In the case of receiving a specific signal sent directly from an exchange at dial-in call reception, level setting of a receptible incoming call is controlled. Concretely, a usual receptible incoming call level in a modem 8 charge in a range of -9 dBm to -43 dBm. Then in the case of receiving a DTMF signal sent directly from the exchange after a primary reply, corresponding to the dial-in call, a loss circuit 22 is controlled to have a receptible incoming call level range of 0 dBm to -34 dBm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication apparatus such as a facsimile apparatus which can respond to a dial-in call.

[0002]

2. Description of the Related Art In a conventional facsimile machine capable of dial-in, a receivable incoming call level is constant. When the 34 modem was used, the reception level was -9 dBm to -43 dBm.

[0003]

However, a facsimile apparatus compatible with dial-in operates so as to receive a DTMF signal transmitted from an exchange after a primary response to an incoming call. The maximum transmission level of the DTMF from the exchange in this case is -3.5 dBm and -4.
This is a composite wave of 5 dBm, and has a transmission level of about -1.5 dBm.

For this reason, in a facsimile apparatus using a modem having a fixed reception level as described above, when a facsimile apparatus is connected to a place close to the exchange, the allowable reception level of the modem and the actual reception level from the exchange are determined. DTMF signal cannot be received, and communication is disconnected.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a communication device capable of correctly and reliably receiving a signal directly transmitted from an exchange when dial-in is received.

[0006]

According to a first aspect of the present invention, there is provided a communication apparatus having a function corresponding to dial-in reception, a reception level setting means for variably controlling a receivable reception level, and receiving a specific signal. When receiving, there is provided control means for changing the setting of the reception level that can be received by the reception level setting means.

[0007] In a second aspect of the present invention, in the first aspect, the specific signal is a signal transmitted directly from an exchange. Further, the third invention of the present application is:
In the first or second invention, the specific signal is a DTMF signal after a primary response.

A fourth invention of the present application is characterized in that, in a reception control method corresponding to dial-in, when a specific signal is received, the setting of a receivable reception level is changed. Furthermore, a fifth invention of the present application provides a computer-readable storage medium storing a program for controlling a communication device having a function corresponding to dial-in reception, a reception level setting for variably controlling a receivable reception level. A program for executing a step and, when a specific signal is received, a control step of changing a setting of a receivable incoming level in the incoming level setting step is stored.

In the first to fifth aspects of the present invention, when performing communication corresponding to dial-in, the setting of the receivable incoming level is changed when a specific signal is received. The signal transmitted from A to the facsimile apparatus B via the exchange has a signal level of -15 dBm or less even when the facsimile apparatus B is close to the exchange, but the signal transmitted directly from the exchange has a higher signal level. In some cases, when a signal transmitted directly from the exchange is received, for example, a loss is inserted, and it is possible to receive the signal correctly and reliably.

[0010]

FIG. 1 is a block diagram showing the configuration of a facsimile apparatus according to one embodiment of the present invention.

An NCU (network control unit) 2 connects to a terminal of the line in order to use the telephone network for data communication and the like.
It controls connection of a telephone exchange network, switches to a data communication path, and holds a loop. If the signal (signal line 20a) from the control circuit 20 is “0”, the NCU 2 connects the telephone line 2a to the telephone 4
If the signal is "1", the telephone line 2a is connected to the facsimile apparatus, and if the signal is "2", the telephone line 2a is connected to the call signal detection circuit 24. In a normal state, the telephone line 2a is connected to the telephone 4 side.

The telephone 4 outputs a signal of signal level "1" to the signal line 4a when off-hook, and outputs a signal of signal level "0" to the signal line 4a when on-hook.

The hybrid circuit 6 separates the transmission system signal and the reception system signal, sends the transmission signal from the addition circuit 12 to the telephone line 2a via the NCU 2, and transmits the signal from the other party via the NCU 2. The signal is received and sent to the modem 8 via the signal line 6a.

The modulator / demodulator 8 includes a DTMF signal, an ITU-T
Recommendation V. 8, V.I. 21, V.I. 27ter, V.I. 29,
V. 17, V.I. The modulation and demodulation are performed based on the signal line 34, and each transmission mode is designated by the signal line 20c. The modulator / demodulator 8 receives a signal output on a signal line 20b, outputs modulated data on a signal line 8a, receives a received signal output on a signal line 6a, and outputs demodulated data on a signal line 8b. Output. Here, when the loss of the loss circuit 22 is 0, the modem 8 assumes that the receivable incoming level on the signal line 2a is, for example, -9 dBm to -43 dBm.

The ANSam sending circuit 10 is a circuit for sending an ANSam signal. When a signal of signal level "1" is output to the signal line 20d, the ANSam sending circuit 10 sends an ANSam signal to the signal line 10a and sends it to the signal line 20d. When the signal of the signal level “0” is being output, no signal is output to the signal line 10a.

The addition circuit 12 receives the information of the signal line 8a and the information of the signal line 10a, and adds the result of the addition to the signal line 12a.
a. The reading circuit 14 reads an image of a document and outputs the read image data to a signal line 14a. The recording circuit 16 is for sequentially recording information output to the signal line 20e line by line.

The memory circuit 18 is used for storing raw information of read data or encoded information, and also for storing received information or decoded information.

The loss circuit 22 is a circuit for inserting a loss into a signal input to the modem 8 and a signal line 20g.
When a signal of signal level “1” is output to
Include a 9 dB loss. As a result, the receivable incoming level on the telephone line 2a is changed from 0 dBm to -34 dBm.
Becomes

On the other hand, when the signal of the signal level "0" is output to the signal line 20g, the loss circuit 22 does not cause loss. Therefore, the receivable incoming level on the telephone line 2a is changed from -9 dBm to -43 dBm.

The call signal detection circuit 24 is a circuit for detecting a call signal. The input impedance of the call signal detection circuit 24 is high, and no DC loop is formed. Further, in the calling signal detection circuit 24, when a signal on the signal line 2d is input and a calling signal is detected, a signal of signal level "1" is output on the signal line 24a, and the calling signal is not detected. Then, a signal of signal level "0" is output to the signal line 24a.

The operation unit 26 has a one-touch dial, abbreviated dial, numeric keys, * / # keys, a set key, a start key, a stop key, a registration key for the registration circuit 28, and other function keys. The respective key information is output to a signal line 26a.

The registration circuit 28 performs a switching operation between a call and a communication by a four-digit telephone number transmitted from the exchange after a primary response for dial-in. A circuit for registering numbers in advance,
For example, it is assumed that 1111 is registered for communication and 1112 is registered for communication.

The false ringing tone generating circuit 30 is a circuit for generating a false ringing tone, and has a signal level "1" on the signal line 20f.
, A pseudo ringing tone is generated, and if a signal of signal level "0" is output to the signal line 20f, no pseudo ringing tone is generated.

The control circuit 20 controls the entire facsimile apparatus. In particular, in the present embodiment, when performing communication corresponding to dial-in, when a specific signal is received, a receivable reception level is set. Is performed to change the setting of.

That is, normally, the receivable reception level is from -9 dBm to -43 dBm, and a specific signal, specifically, a DTM transmitted directly from the exchange after the primary response
When the F signal is received, the loss circuit 22 is controlled so that the receivable reception level is changed from 0 dBm to -34 dBm.

FIGS. 2 to 4 are flowcharts showing the control flow of the control circuit 20 in this embodiment.

In FIG. 2, the operation starts at S0, and at S2
Then, the information of the registration circuit 28 is cleared via the signal line 28a. In S4, a signal of signal level "0" is output to the signal line 20f, and no pseudo ringing tone is generated. In S6, a signal of the signal level “0” is output to the signal line 20g, and the loss of the loss circuit 22 is eliminated.

In S8, the signal "2" is output to the signal line 20a, the signal line 2a is connected to the signal line 2d, and the DC loop is opened. In S10, a signal of the signal level "0" is output to the signal line 20d, and the ANSam signal is not transmitted.

Next, in S12, the information of the signal line 26a is inputted, and it is determined whether or not the registration to the registration circuit 30 is selected. When the registration is selected, the process proceeds to S14, and the call is made via the signal line 30a. For example, the telephone number for communication is registered as 1111 and the telephone number for communication is registered as 1112 in the registration circuit 30, and if registration is not selected, the process proceeds to S16.

In step S16, information on the signal line 24a is input, and it is determined whether or not a call signal has been detected. If a call signal has been detected, the process proceeds to step S20.
Proceed to 18. In S18, other processing is performed. This processing includes a transmission operation and the like.

In S20, a signal of signal level "1" is output to the signal line 20g, and the loss of the loss circuit 22 is set to 9 dB. In S22, a signal “1” is output to the signal line 20a, the signal line 2a is connected to the signal line 2c, and the CML is turned on (primary response).

At S24, D transmitted directly from the exchange
Receive a TMF signal. Thereafter, in S26, the signal line 2
0g, a signal of a signal level “0” is output to the loss circuit 22.
Return the loss of a to 0 dB.

Next, in S28, it is determined whether the signal is for communication or communication by inputting information on the signal line 28a to the detected DTM. If it is for communication, the process proceeds to S30, and if it is for communication, S4 is performed.
Proceed to 2.

In S30, the signal "2" is output to the signal line 20a, the signal line 2a is connected to the signal line 2d, and the DC loop is cut. In S32, a wait for 500 ms is performed. In S34, a signal "1" is output to the signal line 20a, the signal line 2a is connected to the signal line 2c, the CML is turned on, a DC loop is formed, and a secondary response is performed. I do.

The pre-procedure is executed in S36, the reception / recording of an image signal is executed in S38, and the post-procedure is executed in S40.

In S42, the signal "2" is output to the signal line 20a, the signal line 2a is connected to the signal line 2d, and the DC loop is cut. In S44, the timer is set to 30 seconds,
In S46, a signal of signal level "1" is output to the signal line 20f, and a pseudo ringing tone is generated.

In S48, information on the signal line 4a is input, and
It is determined whether or not the user is off-hook. When the user is off-hook, the process proceeds to S52, in which a signal of signal level "0" is output to the signal line 20f to stop the pseudo ringing tone, and a call is made in S54.
Thereafter, information on the signal line 4a is input in S56, and it is determined whether or not on-hook is performed. If on-hook is performed, the process proceeds to S8, and if not, the process proceeds to S54.

If the hook is not off-hook in S48, S
Go to 50. In S50, it is determined whether or not the 30-second timer has timed out.
The process proceeds to S48 if the time is not over.

In S58, a signal of signal level "0" is output to the signal line 20f to stop the pseudo ringing tone, and the flow proceeds to S8.

Although the above-described operation of the control circuit has been described as being performed by the CPU in the control circuit based on a program stored in a ROM, a RAM, or the like in the control circuit, the present invention provides such a circuit. The program is stored in an external storage medium such as a flip-flop, a hard disk, an optical disk, a CD-ROM, or a memory card, and is loaded into a control circuit by a dedicated reading device, and is executed by a CPU in the control circuit. It may be.

In the above embodiment, a stand-alone type facsimile apparatus has been described as an example. However, the present invention is not limited to this. For example, a copy function, an electronic file function, and a data processing function are combined with a communication function. The present invention can be applied to data communication control in a comprehensive data processing system. Further, the present invention can be similarly applied to a communication device separated from a reading circuit and a recording circuit.

[0042]

As described above, according to the first to fifth inventions of the present application, when performing communication corresponding to dial-in, when a specific signal is received, the receivable reception level of the receivable level is determined. Since the setting is changed, for example, a signal directly sent from the exchange can be correctly and reliably received by correcting the signal to a receivable reception level by inserting a loss, for example.

As a result, even when the exchange is near the communication device, for example, the DTMF signal after the primary response at the time of dial-in reception can be reliably received, and proper operation can be obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention.

FIG. 2 is a flowchart showing the operation of the embodiment.

FIG. 3 is a flowchart showing the operation of the embodiment.

FIG. 4 is a flowchart showing the operation of the embodiment.

[Explanation of symbols]

 2 ... NCU, 4 ... telephone, 6 ... hybrid circuit, 8 ... modulator / demodulator, 10 ... ANSam sending circuit, 12 ... addition circuit, 14 ... reading circuit, 16 ... recording circuit, 18 ... memory circuit, 20 ... control circuit, 22 ... Loss circuit, 24 ... Paging signal detection circuit, 26 ... Operation unit, 28 ... Registration circuit, 30 ... Pseudo ringing sound generation circuit.

Claims (5)

[Claims] 1. A communication apparatus having a function corresponding to an incoming call of a dial-in, comprising: an incoming call level setting means for variably controlling a receivable incoming call level; and receiving a specific signal by the incoming call level setting means. A communication device, comprising: control means for changing a setting of a possible incoming call level. 2. The communication device according to claim 1, wherein the specific signal is a signal transmitted directly from an exchange. 3. The communication device according to claim 1, wherein the specific signal is a DTMF signal after a primary response. 4. A reception control method corresponding to dial-in, wherein when a specific signal is received, a setting of a receivable reception level is changed. 5. A receiving level setting step of variably controlling a receivable receiving level in a computer-readable storage medium storing a program for controlling a communication device having a function corresponding to dial-in receiving. And a control step of changing the setting of the receivable level that can be received in the incoming level setting step when the signal is received.