JP3707600B2 - Facsimile machine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a facsimile apparatus having an energy saving function capable of reducing power consumption in a standby state.
[0002]
[Prior art]
Facsimile machines are strongly required to reduce their power consumption in consideration of the environment. Especially in the standby state where there is no operation by the operator and only waiting for an incoming call from the line, it is possible to suppress unnecessary power consumption by suppressing circuit operations other than the operator operation and the function for monitoring the incoming call from the line. Done.
[0003]
In particular, a modem digital signal processing apparatus (hereinafter referred to as a DSP) responsible for modulation / demodulation processing does not consume a small amount of power during its operation in order to perform high-speed signal processing. For example, power supply is not performed or a transition to a low power consumption operation is performed.
[0004]
FIG. 4 is a diagram showing a configuration of a conventional facsimile apparatus having an energy saving function. In FIG. 4, a facsimile apparatus includes a CPU 401, a program ROM (PROGROM) 402, a data RAM (DATARAM) 403, an operation unit 404, a reading unit 405, a writing unit 406, a compression / decompression unit 407, a modem digital signal processing device (modem). DSP) 408, modem analog front end (modem AFE) 409, I / O port 410, power saving operation control unit 411, binarization circuit 412, monitor speaker drive circuit 413, and interface between telephone line and modem It consists of a data access device (DAA) 420.
[0005]
In FIG. 4, a DAA 420 is a part that takes an interface (I / F) between a telephone line and a facsimile machine, and is connected to the telephone line. In the DAA 420, network control functions such as incoming call detection from a line and call processing to a telephone line, and analog signals exchanged with the telephone line are isolated and connected to the modems 409 and 408 and the IO port 410. It has two functions. For this purpose, the DAA is connected to both the modem and the IO port.
[0006]
This DAA 420 insulates the primary side circuit connected to the telephone line, the secondary side circuit connected to the modem, the photocoupler relay, etc., the high impedance termination, and the primary side and the secondary side. It consists of an insulation transformer for giving and receiving.
[0007]
When the facsimile apparatus shifts to the power saving operation, the CPU 401 instructs the power saving operation control unit 411 to stop supplying power to circuits that do not require power supply during the power saving operation including the modem DSP 408 and the modem AFE 409. Reduce power consumption of the entire facsimile machine. At this time, the IO port 410 and the operation unit 404 to which signals required by the power saving operation control unit 411 are connected continue to operate with a minimum power.
[0008]
When there is an incoming call from the telephone line in the power saving operation state, the incoming signal is supplied from the DAA 420 to the directly connected IO port 410, and the power saving control unit 411 detects the incoming call via the IO port 410. ,Confirm. In response to the incoming confirmation of the power saving control unit 411, an interrupt is generated for the CPU 401, and the CPU 401 returns the entire facsimile apparatus to the normal operation.
[0009]
By the way, as a function unique to a facsimile for domestic use, there is an incoming call detection by a tone signal of 1300 Hz from a facsimile communication network (F network). This 1300 Hz tone signal is transmitted at a level substantially equal to the transmitted signal level, unlike a normal ring signal having a large amplitude. When a 1300 Hz tone signal is detected by a simple means, a false detection often occurs.
[0010]
For example, many of the tone detection functions of a modem are based on a narrow band filter, but this method is likely to cause false detection when noise including a 1300 Hz component is superimposed on the line. Therefore, when a modem is used, in the example of FIG. 4, redundancy processing is performed by the CPU 401, and detection is determined only when a 1300 Hz signal is detected continuously for a predetermined time.
[0011]
In a facsimile, a signal on the line is constantly monitored by a high impedance transformer in a state where the line is not closed (not terminated), and a 1300 Hz tone signal is detected. However, since various noises are superimposed on the signal on the line that is not terminated, the detection at 1300 Hz is performed by means other than the modem, such as the frequency counter of the IO port 410.
[0012]
In the facsimile apparatus configured as described above, the DAA 420 that takes an interface (I / F) between the telephone line and the facsimile apparatus is an indispensable component, but the primary side and the secondary side are insulated from each other and the signal is transmitted. In order to send and receive, a relatively large insulating transformer is required, which has been one of the factors that hinder miniaturization of facsimile machines.
[0013]
By the way, with the spread of data communication such as the Internet and digital cellular phones, communication devices such as portable terminals and small terminals have been downsized. Similar to the facsimile apparatus, a communication apparatus connected to a public telephone line requires a relatively large transformer for connection to the line. Recently, however, semiconductor technology and isolation technology have advanced, and devices that substitute the functions of conventional transformers with semiconductor elements have appeared and are becoming popular. For example, Japanese Patent Laid-Open No. 6-98038 constitutes a DAA with an integrated analog circuit and a pulse transformer that is much smaller than the conventional transformer, instead of the conventional large transformer. As another example, there is one in which a similar function is realized by an isolation technique using a capacitor and a semiconductor instead of a pulse transformer (see Japanese Patent Laid-Open No. 9-116642).
[0014]
DAA using these semiconductor elements is expected to further reduce costs in the future due to advances in semiconductor device processes, and further by reducing the number of parts for realizing functions, reducing the board area, etc. Even when employed in a communication device that is not a portable terminal, the cost of the device can be reduced.
[0015]
FIG. 5 shows the configuration of a conventional facsimile apparatus using a DAA composed of these semiconductor elements. In FIG. 5, the facsimile apparatus includes a CPU 501, a PROGAM ROM 402, a DATE RAM 403, an operation unit 404, a modem DSP 508, a power saving operation control unit 511, and a semiconductor DAA 520 that interfaces between a telephone line and a modem DSP 508. Yes.
[0016]
The DAA 520 includes a primary side circuit connected to a telephone line and a secondary side circuit. A network control monitoring circuit is provided in the primary side circuit, and a modem AFE is provided in the secondary side circuit. The function of the transformer is replaced by a semiconductor element or the like. In the typical example of the semiconductor DAA shown here, the connection to the apparatus side is made only through the digital I / F with the modem DSP. This digital I / F is, for example, a serial I / F used for general-purpose CODEC. Along with analog / digital conversion of modulation / demodulation signals and AFE digital signals for digital / analog conversion, a network control instruction / network monitoring state signal, which has been performed by a conventional DAA, is transmitted and received via the serial I / F. The modem DSP has a function of transferring a network control instruction / network monitoring state signal to the CPU in addition to the original modulation / demodulation data processing. The DSP 508 uses a CPU bus as means for exchanging network control instruction / network monitoring state signals with the CPU 501.
[0017]
[Problems to be solved by the invention]
In the example of FIG. 5, as is clear from comparison with FIG. 4, when the modem DSP 508 is not operating, the network monitoring signal cannot be transferred to the CPU 501. Therefore, since it is impossible to detect incoming calls from a telephone line, it is necessary to operate the modem DSP 508 even during power saving operation.
[0018]
As described above, when a modem using the semiconductor DAA 520 is used for a facsimile, an incoming call from the outside is notified via the modem DSP and the digital I / F, so that the DSP is operated even during the power saving operation. Therefore, there is a problem that the power consumption of the facsimile apparatus becomes larger than when the conventional DAA is used.
[0019]
Further, in the semiconductor DAA 520, it is usual that the signal on the line can be detected with a high impedance without closing the line by the setting. However, when the facsimile apparatus has the semiconductor DAA 520 as shown in FIG. 5 and performs a power saving operation, even if the modem DSP 508 is normally operated, the operation of the CPU is suppressed or restricted. Means for avoiding erroneous detection of a 1300 Hz tone signal as described above with reference to FIG. 5 are extremely limited. With such a configuration, if a false detection of a 1300 Hz tone detection signal occurs during the power saving operation, the facsimile apparatus will respond, so the power saving operation will be interrupted and the power will be effectively suppressed. I can't do things. As described above, the malfunction due to the erroneous detection of the tone signal is conspicuous in the erroneous detection of the 1300 Hz signal. However, it is desirable that the tone signal of other frequencies used in the facsimile communication has a low possibility of erroneous detection. Needless to say.
[0020]
Accordingly, an object of the present invention is to provide a low-cost facsimile equipped with an inexpensive semiconductor DAA while suppressing power consumption during power saving operation.
[0021]
It is another object of the present invention to provide a low-cost facsimile using an inexpensive semiconductor DAA by reducing erroneous detection of an incoming call detection tone signal, thereby suppressing power consumption during power-saving operation of the apparatus.
[0022]
It is another object of the present invention to provide a semiconductor DAA having an optimum configuration for detecting a tone signal for detecting an incoming call, thereby reducing the cost of a facsimile apparatus including a low power operation.
[0023]
[Means for Solving the Invention]
According to a first aspect of the present invention, a facsimile apparatus combines a digital signal processing apparatus (hereinafter referred to as DSP) for modulating / demodulating transmission signals and reception signals, a telephone line and the DSP, and is connected to the DSP. A digital interface, a semiconductor data access device (hereinafter referred to as a semiconductor DAA) for analog / digital conversion and digital / analog and network control for modulation / demodulation, a host CPU for controlling the entire facsimile device, and power saving of the facsimile device A power-saving control unit for controlling the operation, and switching the connection of the digital interface of the semiconductor DAA from the DSP to the power-saving control unit and stopping or suppressing the operation of the DSP at the time of power-saving operation of the facsimile apparatus. It is characterized by doing.
[0024]
In the facsimile apparatus according to the first aspect, since the signal from the semiconductor DAA is monitored by the power saving operation control unit instead of the modem DSP during the power saving operation, the power of the modem DSP can be suppressed during the power saving operation. The cost of the facsimile apparatus can be reduced by using the semiconductor DAA.
[0025]
According to a second aspect of the present invention, there is provided a facsimile apparatus for combining a DSP for modulating / demodulating a transmission signal and a received signal, a telephone line and the DSP, a digital interface means connected to the DSP, for modulation / demodulation. Analog / digital converter and digital / analog converter, network control mechanism, semiconductor DAA having an analog output terminal for monitoring communication signals, a comparator for binarizing the analog output of the analog output terminal, It has a frequency counter that detects the frequency of the signal binarized by the comparator, has a power-saving control unit that controls the power-saving operation of the facsimile, and a host CPU that controls the entire facsimile apparatus. In some cases, incoming call detection control of a communication network is performed without using a modulation / demodulation DSP.
[0026]
In the facsimile apparatus according to claim 2, since tone detection is performed using an analog signal output for line monitoring, even if the operation of the modem DSP is suppressed during low power operation, tone detection without false detection, particularly facsimile. The incoming call of 1300 Hz in the communication network can be detected, and the cost of the facsimile apparatus can be reduced by using an inexpensive semiconductor DAA.
[0027]
According to a third aspect of the present invention, there is provided a facsimile apparatus for combining a DSP for modulating / demodulating a transmission signal and a received signal, a telephone line and the DSP, a digital interface means connected to the DSP, for modulation / demodulation. Analog / digital converter and digital / analog converter, network control mechanism, analog output terminal for monitoring communication signals, and digital signal for binarizing and outputting analog signals for monitoring communication signals at predetermined thresholds A semiconductor DAA having an output terminal, a frequency counter for detecting the frequency of the binarized signal from the digital output terminal, a power saving control unit for controlling a power saving operation of the facsimile, and control of the entire facsimile apparatus And a host CPU for performing communication without using a modulation / demodulation DSP during power saving operation. It is characterized in that incoming call detection control is performed.
[0028]
The facsimile apparatus according to the third aspect of the present invention has the same effects as the facsimile apparatus of the second aspect, and further includes a digital output terminal for monitoring communication signals included in the semiconductor DAA. It can be set as the optimal structure.
[0029]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing a configuration of a facsimile apparatus according to the first embodiment of the present invention, which uses a semiconductor DAA and has an energy saving function.
[0030]
In FIG. 1, the facsimile apparatus includes a CPU 101, a PROGRAM 102, a DATARAM 103, an operation unit 104, a modem DSP 108, a power saving operation control unit 111, a semiconductor DAA 120 that interfaces between a telephone line and a modem DSP 108, and a semiconductor DAA 120 and a modem DSP 108. Switching means 130 for switching the connection to the power saving operation control unit 111 side. The reading unit, writing unit, compression / decompression unit, etc. are not shown.
[0031]
The semiconductor DAA 120 connects a network control function such as detection of incoming calls from a telephone line and call processing to the telephone line and an analog signal exchanged with the telephone line in the same manner as in the past. It has two functions. For this purpose, the semiconductor DAA 120 includes a network control monitoring circuit 122 in the primary circuit 121 and a modem AFE 109 in the secondary circuit 123. Although not shown, the modem AFE 109 is provided with an A / D converter for modulation / demodulation, a D / A converter, and a digital interface (digital I / F) for connection to the modem DSP 108. The isolation between the primary side circuit 121 and the secondary side circuit 123 is not an isolation transformer as in the prior art, but is constituted by an integrated analog circuit and an extremely small pulse transformer, or by a capacitor and a semiconductor. The thing which implement | achieved the same function is used.
[0032]
In the embodiment of FIG. 1, the semiconductor DAA 120 is connected to the modem DSP 108 by a changeover switch 130 in a normal state, and a transmission signal and a reception signal are exchanged between the two using a CODEC I / F serial signal. The
[0033]
When the facsimile apparatus shifts to the power saving mode, the CPU 101 instructs the power saving operation control unit 111 to stop supplying power to circuits that do not require power supply during the power saving operation including the modem DSP 108, and the entire facsimile apparatus. Reduce power consumption. At this time, the operation unit 104 to which a signal required by the power saving operation control unit 111 is connected continues to operate with a minimum power. At this time, the power saving operation control unit 111 generates a CODEC I / F switching control signal, switches the changeover switch 130 to the power saving operation control unit 111 side, and changes the CODEC I / F signal of the semiconductor DAA 120 to the power saving operation control unit 111. Connect to.
[0034]
The power saving operation control unit 111 has a serial I / F that can receive a signal from the general-purpose CODEC I / F, monitors the network monitoring state from the semiconductor DAA 120, and interrupts the CPU 101 when an incoming call is detected. The CPU 101 returns the entire facsimile apparatus from the power saving state to the normal operation.
[0035]
As described above, according to the first embodiment, the CODEC I / F serial signal from the semiconductor DAA 120 is monitored by the power saving operation control unit 111 instead of the modem DSP 108 during the power saving operation. Therefore, the modem DSP 108 is used during the power saving operation. The cost of the facsimile apparatus can be reduced by using an inexpensive semiconductor DAA.
[0036]
FIG. 2 is a diagram showing a configuration of a facsimile apparatus according to the second embodiment of the present invention, which uses a semiconductor DAA and has an energy saving function as in FIG.
[0037]
In FIG. 2, a facsimile apparatus includes a CPU 201, a PROGRAM 202, a DATARAM 203, an operation unit 204, a modem DSP 208, a power saving operation control unit 211 having a frequency counter 211a, a semiconductor DAA 220 that interfaces between a telephone line and a modem DSP 208, and A binarization circuit 212 that binarizes an analog signal output for monitoring from the semiconductor DAA 220 and supplies a binarized digital signal to the frequency counter 211a, and a monitor speaker drive circuit 213 are provided. The reading unit, writing unit, compression / decompression unit, etc. are not shown.
[0038]
As in the semiconductor DAA 120 of FIG. 1, the semiconductor DAA 220 includes a network control monitoring circuit 222 in the primary side circuit 221, a modem AFE 109, a monitoring circuit 224, and an analog output of this monitoring circuit in the secondary side circuit 223. An analog output terminal is provided for output. Although not shown, the modem AFE 209 is provided with an A / D converter for modulation / demodulation, a D / A converter, and a digital I / F for connection to the modem DSP 208. The isolation between the primary side circuit 221 and the secondary side circuit 223 is not an insulation transformer as in the prior art, but is constituted by an integrated analog circuit and an extremely small pulse transformer, or by a capacitor and a semiconductor. The thing which implement | achieved the same function is used.
[0039]
The monitor circuit 224 of the semiconductor DAA 120 normally sends a call signal on the line being called to the secondary side circuit 223 so that the operator can confirm the connection of the line by driving a speaker of the facsimile apparatus. Outputs analog output. In the present embodiment, the analog output is binarized not only by the speaker drive circuit 213 but also by a binarization circuit 212, and a signal having an amplitude exceeding an appropriate threshold value is binarized and supplied to the frequency counter 211a as a digital signal. The frequency counter 211a monitors the period of the binarized digital signal, and determines that it is detected only when the period of a predetermined range can be detected continuously a predetermined number of times.
[0040]
In the embodiment of FIG. 2, in the normal operation state, the modem DSP 108 is normally supplied with power, and is connected to the semiconductor DAA 120, and the transmission signal and the signal are transmitted between the two using the CODEC I / F serial signal. Received signals are exchanged.
[0041]
When this facsimile apparatus shifts to the power saving mode, the CPU 201 instructs the power saving operation control unit 211 to stop supplying power to circuits that do not require power supply during the power saving operation, including the modem DSP 208, and the entire facsimile apparatus. Reduce power consumption. At this time, the operation unit 204 or the like to which a signal required by the power saving operation control unit 211 is connected continues to operate with a minimum power.
[0042]
During the power saving operation, when there is an incoming call detection by a 1300 Hz tone signal from the facsimile communication network, it is transmitted from the primary side circuit 221 of the semiconductor DAA 220 to the secondary side circuit 223 in the form of an analog signal. The 1300 Hz tone signal is extracted by the monitor circuit 224 and output from the analog signal output terminal of the secondary side circuit 223. The 1300 Hz tone signal from the analog signal output terminal is binarized by a binarization circuit 212 and a signal having an amplitude exceeding an appropriate threshold value is input to the frequency counter 211a as a digital signal. In the frequency counter 211a, a cycle value for detection determination and the number of times to be detected are set in advance, the cycle of the binarized digital signal is monitored, and the cycle in a predetermined range is Only when a predetermined number of times can be detected continuously, it is determined to be detected, an interrupt is generated for the CPU 201 as an incoming call detection from the facsimile network, and the CPU 201 returns the entire facsimile apparatus to normal operation.
[0043]
As described above, according to the second embodiment, the analog signal output for line monitoring provided in the semiconductor DAA 220 is used, the tone signal is detected after the signal is digitally processed, so that the power saving operation is performed. Even if the operation of the modem DSP 208 is sometimes suppressed, it is possible to perform tone detection without false detection, particularly detection of incoming calls at 1300 Hz in the facsimile communication network, and reduce the cost of the facsimile apparatus using an inexpensive semiconductor DAA. it can.
[0044]
FIG. 3 is a diagram showing a configuration of a facsimile apparatus according to the third embodiment of the present invention. Only the semiconductor DAA 320 is different from FIG. 2, the other configurations are the same, and the corresponding components are the same. Are given the same reference numerals.
[0045]
In the semiconductor DAA 320, the binarization circuit 212 is incorporated in the secondary side circuit 323. As a result, the 1300 Hz tone signal extracted by the monitor circuit 224 is binarized into a signal having an amplitude exceeding an appropriate threshold value by the binarization circuit 212 and output as a digital signal from the digital signal output terminal of the semiconductor DAA 320. The Other operations are the same as those in the second embodiment of FIG.
[0046]
According to the third embodiment, the same effect as in the second embodiment is obtained, and the semiconductor DAA 320 is further provided with a binarization circuit 212 for monitoring a tone signal and a digital output terminal. Therefore, it is possible to obtain an optimum configuration for detecting incoming calls at 1300 Hz in a facsimile communication network.
[0047]
【The invention's effect】
In the facsimile apparatus according to the first aspect, since the signal from the semiconductor DAA is monitored by the power saving operation control unit instead of the modem DSP during the power saving operation, the power of the modem DSP can be suppressed during the power saving operation. The cost of the facsimile apparatus can be reduced by using the semiconductor DAA.
[0048]
According to another aspect of the present invention, since the tone is detected by using the analog signal output for line monitoring, even if the operation of the modem DSP is suppressed at the time of low power operation, tone detection without false detection, particularly facsimile. The incoming call detection at 1300 Hz of the communication network can be performed, and the cost of the facsimile apparatus can be reduced by using an inexpensive semiconductor DAA.
[0049]
The facsimile apparatus according to the third aspect of the present invention has the same effects as the facsimile apparatus of the second aspect, and further includes a digital output terminal for monitoring communication signals in the semiconductor DAA. It can be set as the optimal structure.
[Brief description of the drawings]
FIG. 1 is a diagram showing a configuration of a facsimile apparatus according to a first embodiment of the present invention.
FIG. 2 is a diagram showing a configuration of a facsimile apparatus according to a second embodiment of the present invention.
FIG. 3 is a diagram showing a configuration of a facsimile apparatus according to a third embodiment of the present invention.
FIG. 4 is a diagram showing a configuration of a conventional facsimile apparatus having an energy saving function.
FIG. 5 is a diagram illustrating a configuration of a facsimile apparatus using a conventional semiconductor DAA.
[Explanation of symbols]
108,208 Modem DSP
111, 211 Power saving operation control unit 212 Binary circuit 120, 220, 320 Semiconductor DAA
122, 222 Network control monitoring circuit 109, 209 Modem AFE
224 monitor circuit 130 switching circuit

Claims (3)

A digital signal processing device (hereinafter referred to as DSP) for modulating / demodulating a transmission signal and a reception signal;
A telephone line and the DSP, which are connected to the DSP, a digital interface connected to the DSP, an analog / digital conversion and digital / analog for modulation / demodulation, and a semiconductor data access device (hereinafter referred to as a semiconductor DAA) for network control. )When,
A host CPU for controlling the entire facsimile apparatus;
A power-saving control unit that controls a power-saving operation of the facsimile apparatus, and at the time of the power-saving operation of the facsimile apparatus, the connection of the digital interface of the semiconductor DAA is switched from the DSP to the power-saving control unit, and the DSP A facsimile machine characterized by stopping or suppressing its operation. A DSP for modulating / demodulating transmission signals and reception signals;
A telephone line and the DSP are combined, and digital interface means connected to the DSP, analog / digital converter and digital / analog converter for modulation / demodulation, network control mechanism, and communication signal are monitored. A semiconductor DAA having an analog output terminal for
A comparator that binarizes the analog output of the analog output terminal;
A power saving control unit that has a frequency counter that detects the frequency of the signal binarized by the comparator and controls the power saving operation of the facsimile;
A host CPU that controls the entire facsimile apparatus;
A facsimile apparatus characterized by performing incoming call detection control of a communication network without using a modulation / demodulation DSP during a power saving operation. A DSP for modulating / demodulating transmission signals and reception signals;
A telephone line and the DSP are combined, and digital interface means connected to the DSP, analog / digital converter and digital / analog converter for modulation / demodulation, network control mechanism, and communication signal are monitored. A semiconductor DAA having an analog output terminal for output, a digital output terminal for binarizing and outputting an analog signal for monitoring a communication signal at a predetermined threshold;
A power saving control unit that has a frequency counter that detects the frequency of the binarized signal from the digital output terminal and controls the power saving operation of the facsimile;
A host CPU that controls the entire facsimile apparatus;
A facsimile apparatus characterized by performing incoming call detection control of a communication network without using a modulation / demodulation DSP during a power saving operation.

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