JPS6028372A - Facsimile equipment - Google Patents

Abstract

PURPOSE:To attain sure polling communication independently of timing of depression of a start button by providing a means detecting a received signal having a prescribed frequency and a means measuring the length of the received signal so as to discriminate the kind of the received signal after an initial identification signal is transmitted. CONSTITUTION:When a signal of 2,100Hz is received by a 2,100Hz signal detecting circuit 15, a timer circuit 17 set to 4sec is started. If the signal is interrupted before the time of the timer circuit 17 is over, it is decided that signal of 2,100 Hz is a CED (called station identification signal) to transmit an NSF signal (non-standard device signal) and a DIS signal (digital identification signal) again. When the phase matching of 9Hz is finished by a phase matching detection circuit 16, the mode moves to the standard mode communication of a mini-fax. When the phase matching of 6Hz is finished by the phase matching detection circuit 16, a timer circuit 18 set to 6.5sec at the point of time is started. If the signal is interrupted within 6.5sec, the communication of the mini-fax with high quality mode is attained.

Description

TECHNICAL FIELD The present invention relates to a facsimile machine, and more particularly to a facsimile machine having a polling function.

BACKGROUND OF THE INVENTION Conventionally, facsimile machines having a polling function are known. In this polling communication, a document is set on the image transmitting side device and placed in an automatic transmission state, a so-called polling standby state, and then the image receiving side makes a call to perform automatic transmission.

To have a device that is waiting for polling transmit,
It is sufficient to call this waiting device from the image receiving side and press the reception start button at a predetermined timing, but this timing may cause the communication to end due to an error.

FIG. 1 shows an example of such an error. The right side of FIG. 1 shows a signal sent by a facsimile machine into which a document is placed while waiting for polling, and the left side shows a signal sent by a facsimile machine about to perform polling reception. However, in the following explanation, only the signal names will be described for standard signals specified in the CCITT Recommendations, unless they are important, and the frequencies, formats, functions, etc. will not be described in detail.

In FIG. 1, the symbol 1 indicates the CED signal (
(Called Station Identification Signal) This is a signal indicating that the called device is a non-voice terminal. This signal is sent in response to a call, and if the operator on the calling side who wants to perform polling reception hears this CHD signal through the handset and immediately presses the reception start button, the NSF signal and DIS signal will be sent from the calling side. The image is transmitted, the transmission and reception are alternated, and the called device that is on standby for polling can be caused to transmit the image.

However, if the reception start button is not pressed, the called device in standby receives a binary procedure signal consisting of the following NSF signal (non-standard equipment signal) 2 and DIS signal (digital identification signal) 3, as shown in the figure. Send out. moreover,
Assuming that the called device that is on standby for polling is a device that can also perform tonal procedures, then the GI2 signal (Group 2
The NSF signal 2 and DIS signal 3 prefixed with 4 (identification signal) are sent out again from the called side.

At this stage, if the reception start button is pressed with a delay as shown in the figure, after the second DIS signal 3 is sent from the called side, the calling side equipment receives CED signals 1. NSF signal 2,
An attempt is made to transmit DIS signal 3 and receive an image.

But here the called device is still in receive mode and
When CHD signal 1, which is a tonal signal of 21.00 Hz, is received, it is mistaken as a phase signal of GC2, (Group 2 command signal) or mini-fax, etc., and attempts to match the phase. Since no signal is sent, the process ends in error.

OBJECTS The present invention has been made in view of the above points, and an object of the present invention is to provide a facsimile device that can perform reliable polling communication regardless of the timing at which a start button is pressed.

EXAMPLES Hereinafter, the present invention will be explained in detail based on examples shown in the drawings.

FIG. 2 shows the structure of the facsimile machine of the present invention. In the same figure, the symbol LO indicates the line 1 for using the telephone network for data communication, etc.

This is an NCU (network control unit) that is connected to terminal a and controls connections to the telephone switching network, switches to data communication paths, and maintains loops.

The output of this NCUIO is transmitted to the equalizer 1 via the signal line 10b.
1 is input.

The equalizer 11 is for correcting attenuation distortion, group delay distortion, etc. of the telephone line, and its output is sent to the AG via the signal line 11a.
C (automatic gain adjuster) 12 and signal detection circuit 14.

The AGC 12 amplifies the received signal attenuated by the telephone line 10a to a constant level, and its output is input to the demodulator 13 and the 2100 Hz signal detection circuit 15.

The demodulator 13 is an AM-PM-VSB demodulator, and the AGC 22
After extracting the carrier from the output signal and performing synchronous detection, it further performs aftereffect rectification and outputs the binarized signal to the phase matching detection circuit 16 via the signal line 13a.

The signal detection circuit 14 inputs the output of the equalizer 11, and sends an rlJ signal to the signal line 14 when a signal is being sent from the other device, and sends a "0" signal to the signal line 14 when the signal is not being received.
Output to a. Here, the detection condition is, for example, 3 consecutive
Receive a signal continuously for 0m5 or more, or 30. m
It is assumed that the signal switches from "0" to "1" or from "1" to "0" when the signal is not received for more than s.

The 2100Hz signal detection circuit 15 inputs the output of AGCl 2 and detects a 2100Hz signal, which has a frequency of about 0.
When the signal is received for 75 seconds, a pulse is generated on the signal line 15a.

The phase matching detection circuit 16 inputs the output of the demodulator 13,
If phase matching is completed when a phase signal of 6 Hz or 9 Hz is received for 3 lines consecutively, the signal is sent to signal line 16a in the case of 6 Hz, and to signal line 1 in the case of 9 Hz.
6b, respectively.

The above signal lines 14a, 15a, and 16a.

The signal 16b is input to the control circuit 19. A timer circuit 17 is connected to the control circuit 19 via signal lines 19a and 17a, and a timer circuit 18 is connected via signal lines 19b and 18a.

The control circuit 19 is composed of a microprocessor or the like, and controls the entire apparatus, and performs the following operations.

When the 2100'Hz signal detection circuit 15 receives a 2100Hz signal, the timer circuit 17, which is set to 4 seconds, is started (4 seconds is the longest time of the CHD signal). If the signal is cut off before the timer circuit 17 times out, the 2100H
The signal z is determined to be a CED signal, and the NSF signal and DIS signal are transmitted again.

Furthermore, when the phase alignment detection circuit 16 completes the phase alignment at 9 Hz, the process shifts to standard mode communication for mini-fax.

When the phase matching detection circuit 16 completes the 6Hz phase matching, the timer circuit 1-8, which is set to 6.5 seconds, is started at that point (this 6.5 seconds is the longest phase signal in Group 2 mode). time). 6
．． If the signal is cut off within 5 seconds, communication is performed in the mini-fax high quality mode.

Next, the operation of the above configuration will be explained in detail with reference to FIGS. 3 and 4.

FIG. 3 is a flowchart showing the control procedure of the control circuit 19 described above, and only routines related to the present invention are shown. It is assumed that this routine is entered after the second DIS signal 3 in FIG. 4 is sent. FIG. 4 is an explanatory diagram similar to FIG. 1, and up to the first and second transmission of the DIS signal 3, exactly the same signal exchange as in FIG. 1 is performed.

In step S30 in FIG. 4, the process waits until a pulse is generated on the signal line 15a, that is, until a 2100 Hz signal is received for about 0.75 seconds. If a signal of 2100 Hz is received, the process moves to step S31.

In step S31, a pulse is generated on the signal line 19a, and 4
The timer circuit 17, which is set to seconds, is started.

Subsequently, in step S32, it is determined whether the signal line 14a is at level "0", that is, whether the signal from the other party is disconnected. If the signal is disconnected, the process moves to step S33, where it is determined that the received signal is a CHD signal, and the NSF signal and DIS signal are transmitted again. If not, the process moves to step S34.

In step S34, it is determined whether a pulse has been generated on the signal line 16b, that is, whether 9 Hz phase matching has been completed. If this step is affirmative, the process moves to step S35, and the process moves to communication in the mini-fax standard mode; if this step is negative, the process moves to step S336.

In step S36, it is determined whether a pulse has been generated on the signal line 16a, that is, whether the 6Hz'z phase matching has been completed. If this step is affirmed, the process moves to step 338, and if this step is negative, the process moves to step S37.

In Stella 7'S37, it is determined whether a pulse has been generated on the signal line 17a, that is, whether the timer circuit 17 that was brought into the state in step S31 has timed out. If 4 seconds have not elapsed and the time has not exceeded, the process returns to step S32, and if a pulse is generated, and 4 seconds have elapsed, the process returns to step S334.

In step 33B, a pulse is generated on the signal line 19b, and
．． Start the timer circuit 18, which is set to 5 seconds.

Subsequently, in step S39, the signal on the signal line 14a is input, and it is checked whether the level is "0", that is, whether the signal from the other party's device is disconnected. If this step is affirmed, the 6Hz phase matching will be completed as shown in the subsequent steps, and the 6Hz phase matching will be completed after the completion of the phase matching.
．． Since this is a case where the phase signal is cut off within 5 seconds, the process moves to step S40 and the communication moves to G2 mode. 1. If step S39 is negative, step S
41.

In step S41, it is determined whether a pulse has been generated on the signal line 18a, that is, whether the set time of 6.5 seconds of the timer circuit 18, which was brought into the state in step 538, has elapsed. If this step is denied, the process returns to step 339, and if it is affirmed, the 6Hz phase matching is completed and the phase signal is not cut off even after 6.5 seconds have passed after the completion of the phase matching. So, Step S
42, the mini-fax is received in high quality mode.

As described above, even if the other party's reception start button is not pressed immediately after the first CHD signal during polling standby, an error termination will not occur. This situation is shown in FIG.

As shown in FIG. 4, if the calling side's CED signal 1 is received immediately after the second transmission of the initial identification signal including the GI2 signal 4, a loop of steps 330 to 332 to step S37 in FIG. The length of a 2100 Hz signal was measured at
Since it is determined that the signal is an HD signal and the process moves to step S33, there is no error termination here as in the conventional case. After receiving this CED signal l from the calling side, this device
It transmits signal 4, NSF signal 2 and DIS signal 3 and waits for the response, but the first GI2 signal 4 to NSF signal 3 overlap on the line with the calling side's NSF signal 2 and DIS signal 3, as shown in the figure. Therefore, the response by the calling side's NSC signal (non-standard device command signal) 5 and DTC signal (digital transmission command signal) 6 is the second GI2 signal 4 to
This occurs after the DIS signal 3 is sent.

The NSC signal 5 and the DTC signal 6 are for responding to the NSF signal 2 and the DIS signal 3, respectively, and thereafter automatic polling transmission similar to the conventional one is performed.

Additionally, if a GC2 signal or a mini-fax phase signal is received from the other party's device at the same timing as the previous CHD signal, it is possible to switch to each mode as described above, and image transmission can be performed without error. Ru.

Effects As is clear from the above explanation, according to the present invention, - a means for detecting a signal of a predetermined frequency received after the initial identification signal is received, and a means for measuring the length of the received signal are provided, and the initial identification signal is Since a configuration is adopted that determines the type of signal received after the signal advances, even if a CHD signal is received after receiving the initial identification signal, it will not be misidentified as a phase signal and an error termination will occur. It is possible to provide an excellent facsimile device that can reliably perform polling communication no matter what timing an operator on a calling side presses a start button to receive a call.

[Brief explanation of drawings]

FIG. 1 is a signal explanation diagram showing the drawbacks of the conventional facsimile machine, FIG. 2 is a block diagram explaining the configuration of the facsimile machine of the present invention, and FIG. 3 is a flowchart diagram explaining the processing procedure of the device of FIG. 2. , FIG. 4 is a diagram of the same format as FIG. 1, and is a signal explanatory diagram showing the operation of the facsimile apparatus of the present invention. 10...NCU l l...equal stopper 12...AG
, C13...Demodulator 14...Signal detection circuit 15...2100Hz signal detection circuit 16...Phase matching detection circuit 17.18...Timer circuit 19...Control circuit Fig. 1 Nougin 11 'J) (穎d!t41i) 4th word

Claims (1)

[Claims] In a facsimile machine having a polling function, means for detecting a signal of a predetermined frequency received after transmitting an initial identification signal and means for measuring the length of the received signal are provided, and the type of signal received after the initial identification signal is advanced is determined. A facsimile device characterized by: