JPH02264538A - Communication equipment - Google Patents

Abstract

PURPOSE:To sample a sine-wave subjected to phase modulation and to output a digital data equal to a digital-converted value by reading the digital data from a storage means at an interval based on a picture signal. CONSTITUTION:In this example, picture information is sent to a facsimile equipment 14 and a printout function of the equipment 14 prints out the picture information. The transmission information to the equipment 14 is converted by a sub CPU 18 according to the facsimile modulation rule and PCM companding rule while keeping the digital code as it is. Then an extension interface 16 decodes the converted PCM code into an analog signal and the signal is sent to the equipment 14. On the other hand, the control signal sent from the equipment 14 is converted into the digital signal from the analog signal by a MODEM 7. Thus, in this example, the comparatively inexpensive low speed MODEM 7 is used and the CPU 18 can fulfill the same function without using expensive MH code, decoder and high speed MODEM.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a communication device that transmits data by modulating a signal.

[Conventional technology]

Traditionally, communication devices that send information to facsimile machines are
For example, the configuration shown in FIG. 4 was required.

In the figure, 2 is a central control unit (CPU), 3 is a memory into which the central control unit 2 writes or reads data, and 4
is a parallel-to-serial and serial-to-parallel converter,
5 is a MH (Modified Huffman) encoding/decoding device; 6 is a high-speed modulation/demodulation device such as V, 27 tar standard; 7 is a low-speed modulation/demodulation device such as V, 21 standard for well-known FAX procedures; 8 and 9 are changeover switches. , 10 is a 2-wire to 4-wire converter, and 11 is a communication line, which is connected to a facsimile machine.

(Problems to be Solved by the Invention) However, in the conventional example described above, the MH encoding/decoding device 5 and the modulation/demodulation device 6 are expensive, resulting in an expensive device as a whole.

(Means for Solving the Problems) According to the present invention, an oscillation means for generating a sine wave, a first generation means for generating a control signal, and a sine wave generated by the oscillation means based on the control signal. a frequency modulation means for frequency modulating; a storage means for storing a plurality of digital data corresponding to the waveform of the sine wave; a second generation means for generating an image signal; To generate a phase modulated signal without using an oscillation means by providing a reading means for reading out data and outputting digital data equivalent to a value obtained by sampling and digitally converting a phase modulated sine wave. I can do it.

(Embodiment) Fig. 1 shows an embodiment of the present invention, and is a configuration diagram of a system centered on a communication device having a telephone conversion function. It is a communication device that has an exchange function for the device 14, and is also called a main device or a private branch exchange. 2 is a central control device, 3 is a memory, and 4 is a parallel-serial/serial-
The parallel converter 7 is a low speed modem (MODEM) and has a sine wave oscillator 7o. MODEM7 generates a sine wave oscillator 7 based on the signal input from the switch 8 side.
By modulating the frequency of the sine wave generated by o, C0DEX1
Output to 20. Furthermore, the MODEM 7 demodulates the analog modulation signal input from the CODEC 7 into a serial digital signal based on the sine wave generated by the oscillator 7o, and outputs the serial digital signal to the switch 8.

8 and 9 are changeover switches, and 2 to 9 correspond to those with the same numbers in FIG. 5, respectively. Further, 12 is an outside line, 13 is an extension telephone, 14 is a facsimile machine housed in the extension, 15 is an outside line interface, 16 is an extension interface, 17 is a call path using a time switch, etc.
8 is a sub CPU, 19 is a memory into which the sub CPU writes or reads, 20 is an encoding/decoding device,
21, 22, 23, 24.25 are P CM highways.

In this embodiment, image information is transmitted to the facsimile device 14,
The image information is printed out using the printout function of the facsimile device 14. The image information to be transmitted to the facsimile machine 14 is converted by the sub CPU 18 as digital code according to the facsimile modulation side and the PCM companding rule. Then, the extension interface 16 decodes the converted PCM code into an analog signal and transmits it to the facsimile machine 14. On the other hand, the control signal transmitted from the facsimile machine is converted from an analog signal into a digital signal by the modulation/demodulation device 7. Therefore, in this embodiment, a relatively inexpensive low-speed modem 7 is used. However, expensive MH
Encoder/decoder (5 in Figure 4) and high-speed modulation/demodulation device (
6) shown in Figure 4 is not used, and the sub CPU 18 composed of a general-purpose microcomputer etc. performs the same function.
An inexpensive communication device can be configured.

- As an example, FIG. 2 shows a procedure in which the system shown in FIG. 1 transmits call charge data required for an outside line 12 during a certain fixed period to a facsimile machine 14 in response to an instruction from an extension telephone 13. For call charge data, call extension 1
According to instructions from 3, the data is totaled by type of extension telephone or by external line 12 if there are a plurality of external lines 12, and stored in the memory 3.

The extension interface 1 indicates that the extension telephone 13 has been operated to transmit call charge data to the facsimile device 14.
6 (step 5IOI), the central controller 2 reads out the status of the facsimile machine 14 from the status table in the memory 3 (step 5102). If the facsimile device 14 is not in communication, the extension interface 16c is instructed to call the facsimile device 14 (step 5103). Extension interface 16
When the response detection circuit in c detects a response from the facsimile machine 14 (step S104), the central control unit 2 again instructs the extension interface 16c to stop sending out the calling signal (step 5105), and then the memory 3
facsimile 14 is registered in the status table. Then, the central processing unit 2 sends a well-known FA to the sub CPU 18.
Instructs to start the X transmission procedure (step 5106)
. Furthermore, communication paths are connected in both directions between the extension interface 16c and the switch 9 (step 5107).

The sub CPU 18 performs a well-known FAX (facsimile) procedure via the telephone line 17 and the extension interface 16c in accordance with the program stored in the memory 19 (step 5108). The fax procedure is 30% even in G II+ standard.
A relatively inexpensive low-speed MODEM with 0DPS and low speed.
7 can be used. That is, the sub CPU 18
A transmission signal sent from the facsimile device 14 to the facsimile device 14 is first converted into a serial signal by the parallel-serial converter 4.

Furthermore, based on the serial signal output from the parallel-serial converter 4, the MODEM 7 frequency modulates (FSX) the sine wave generated by the oscillator 70. And MODEM
The modulated signal outputted by 7 is encoded by the C0DEC 20 in order to be loaded on the PCM highway 21. The signal passing through the communication path 17 enters the extension interface 16C via the highway 22. Then, it is decoded by the C0DEC of the extension interface 16c and reaches the facsimile machine 14 as an analog signal. Conversely, the received signal from the facsimile machine 14 is sent to the extension interface 16.
The signal is PCM coded (encoded) by the C0DEC within c, passes through the PCM highway 22, the communication path 17, and the PCM highway 21, and is decoded into an analog signal by the C0DEC 20. Then, the MODEM 7 demodulates the serial digital signal again using the oscillator 70, parallelizes the signal using the serial-parallel converter 4, and reaches the sub-CPU 18.

When the predetermined FAX procedure is completed as described above and arrangements are made to send the information to the facsimile machine 14, the sub-c
puia is switch 8. Switch 9 is switched so that switch 8 and switch 9 are directly connected (step 5t)
o9). Upon receiving the notification (step 5tio), the central control unit 2 transfers the information to be transmitted to the facsimile machine 14, ie, call charge data, to the sub CPU 18 through the memory 3, and develops it into a bitmap (step 5111). Sub C
The PU 18 stores the transferred call charge data in the temporary memory 19.
Save up to. The sub CPU 18 reads data, for example, one line at a time, from the memory 19, modulates it according to a predetermined facsimile modulation rule (step 5112), and further,
PCM code according to PCM companding rules (Step 5)
113).

This operation will be explained using FIG. 3. The memory 19 stores a table having the peak values of each sine wave divided into 40 equal parts as PCM codes. Then, the sub CPU 18 shifts the address by nine addresses and cyclically reads out the peak value of the PCM code from the table, thereby reproducing the sine wave. That is, for example, po, p
, , P18+P27. P36. P5 (5=m
Od4o(45)).

Read out in the order of PI3... When performing phase modulation, the address is shifted by 19 to advance +90@. That is, for example, if P33 is read out after p+4, +90'' phase modulation can be achieved.

Moreover, in the case of +180', it is sufficient to shift the address by 29 addresses. When the angle is +270°, it is enough to shift the address by 39 addresses.

The sub CPU 18 compresses the bit data read line by line from the memory 18 using the MH (Modified Huffman) method or the like. Then, the PCM code of the peak value is read from the address corresponding to the compressed data. In other words, if the value to be transmitted is 00, there is no phase change, if it is 01, it is 90°, if it is 11°, it is 180°, and if it is 10°, it is 2
Shift the phase by 70°. By doing so, data transmission using phase modulation becomes possible. And sub CP018
The generated PCM code is sent to parallel-serial converter 4.
Convert to serial signal by The serial signal is
PCM Highway 21, Call Route 17. C0DEC in extension interface 16c through PCM highway 22
is decoded into an analog signal by facsimile machine 1.
4 (step 5114), and when the information to be transmitted has been completed (step 5115), the central control unit 2 sends an instruction to the sub CPU 18 to terminate the axis transmission.

The sub CPLJ 18 thereby returns the switch 8.9 to the state shown in the figure and performs a predetermined FAX procedure using the MODEM 7 (step 5116). When it is detected that the fax has been sent normally according to the FAX procedure (step 311B), the central control device 2 is notified (step 3119).

On the other hand, the central control device 2
The communication path between the two is disconnected (step 5120). Furthermore,
When the central control unit 2 is informed from the extension interface 16c that the facsimile machine 14 has been disconnected, it re-enters the availability of the facsimile machine 14 into the status table.

[Other Examples]

The above is an example of starting the transmission of call charge data to the facsimile machine 14 by operating the extension telephone 13a or 13b, but the "information transmission request" in step 5101 is
For example, the central control device 2 may have a clock and automatically transmit the information by detecting that a certain time has arrived.

It goes without saying that the information transmitted to the facsimile machine may include setting data, fault data, traffic data, etc. in addition to call charge data.

As explained above, according to this embodiment, low-speed fax procedures are sent and received via MODEM, and high-speed data transmission is performed by the sub CPU to create facsimile signals, making communication cheaper than the conventional configuration. It becomes a device.

〔Effect of the invention〕

According to the present invention, by reading digital data from the storage means at intervals based on the image signal, digital data equivalent to a value obtained by sampling and digitally converting a phase-modulated sine wave can be obtained without using an oscillation means. It can be output.

Therefore, since no oscillation means is required, costs can be reduced.

[Brief explanation of drawings]

FIG. 1 is a system configuration diagram implementing the present invention, FIG. 2 is a flowchart showing the procedure for transmitting facsimile information in this embodiment, FIG. 3 is a map diagram of the waveform table of the memory 19, and FIG. FIG. 1 is a configuration diagram of a conventional communication device. 2 is a central control unit, 3 is a memory, 4 is a parallel-to-serial converter, and 7 is a low-speed MODEM. 14 is a facsimile machine, and 70 is an oscillator.

Claims (1)

[Scope of Claims] Oscillation means for generating a sine wave; first generation means for generating a control signal; frequency modulation means for frequency modulating the sine wave generated by the oscillation means based on the control signal; A storage device that stores a plurality of digital data corresponding to the waveform of the wave, a second generation device that generates an image signal, and a phase modulated signal that is phase modulated by reading the digital data from the storage device at intervals based on the image signal. 1. A communication device comprising: reading means for outputting digital data equivalent to a value obtained by sampling and digitally converting a sine wave.