JPS62149248A - Terminal calling type transmission equipment - Google Patents

Abstract

PURPOSE:To send a data with high reliability by allowing a center equipment to release a line when a reception data is normal to bring the state to the re-reception state at a fault and allowing a terminal equipment to apply re- transmission when no call tone is received after the data transmission thereby eliminating the need for the sending of a reply signal. CONSTITUTION:When a data transfer request takes place, a control section 38 of a terminal equipment 30 throws a changeover section 31 to the position of the equipment 30 and closes a closing section 33. When a call signal detection section 55 of a center equipment 50 detects a call signal, a control section 56 closes the closing section 51 to form the incoming state. The equipment 30 sends a data from a transmission section 37 in this state. When the equipment 50, when the data received by a reception section 51 is erroneous, keeps the closing section 51 continuously. When a call tone detection section 36 does not detect a call tone for a prescribed time after data transmission, the equipment 30 resends the data. The equipment 50 receives the data and when the data is normal, the closing section 51 is opened. Thus, a telephone line 40 is opened and the call tone is sent from an exchange 41 to the equipments 30 and 50.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field of the Invention) The present invention relates to an improvement in a terminal-originated transmission device in which data is transmitted in only one direction from a terminal device to a center device using a telephone line.

[Technical background of the invention]

Conventionally, when transmitting data from a terminal device to a center device in data transmission, the terminal device uses JIS-
Parity pits and block check characters as shown in C6360 are added and sent, while the center device checks the received data according to the transmission procedure shown in JIS-06362 and if a transmission error is detected. Control is performed to ensure accurate data transmission by requesting retransmission to the terminal device.

By the way, there are devices that transmit data through telephone lines, and in this case, it is not practical to install a telephone line exclusively for transmission on the terminal side, so it is necessary to use a general subscriber telephone line to switch between calls and data transmission. It is efficient to do so. However, in order to switch between calls and data transmission, it is not possible to automatically receive calls because it is difficult to distinguish between normal calls and data transmission when a call is received, and an automatic dialing method from the terminal device must be adopted. I can't do it. In this way, since the center device cannot request data transmission to the terminal device, it is an absolute requirement to receive data reliably.

In addition, a common method used to ensure the reliability of data transmission is the terminal transmission method, in which the data receiving side judges the validity of the data and sends a response back to the data sending side. On the other hand, on the data transmitting side, the response that is returned after data transmission is checked to determine whether the data has been transmitted correctly, and if necessary, the data is retransmitted to ensure data transmission.

FIG. 5 is a block diagram of a conventional terminal originating transmission device that employs the terminal originating method. Terminal device 1 has telephone line 2 and exchange 3
The data transmission is performed as shown in the operation timing chart shown in FIG. 6. Note that in FIG. 6, A indicates the operation of the terminal device 1, and B indicates the operation of the center device 4. That is, as shown in FIG. 5, at time t1 when data is to be transmitted,
First, the control section 5 in the terminal device 1 switches the switching section 6 from the telephone 7 to the terminal device 1 side, and the closing section 8
is closed. As a result, the dial tone H of 400H2 from the exchange 3 is received by the dial tone detector 11 through the coupler 9 and the interface 1o, and upon confirmation of this dial tone, the control section 5 receives a selection signal (dial signal) D from the transmitter 12.
send out.

This dial signal is sent from the telephone line 2 to the exchange 3, and from this exchange 3 a ringing signal (ringing φ tone) Y
The data is sent to the center device 4 as a. This call signal Y is input to the center device 4, detected by the call signal detection section 13, and the detection signal is issued to the control section 14, and at this time t.
At step 2, the control section 14 closes the closing section 15 to enter the incoming call state. After entering this state, in the terminal device 1, the transmitter 12
Data DT1 is sent from. This data DTI is transmitted to the center device 4 via the telephone line 2 and the exchange 3.

The signal is then received by the receiving unit 18 through the coupler 16 and interface 17 of the center device 4 . The control unit 14 determines whether the received data DTI is normal or not.

Here, if an abnormality is detected, the control section 14 causes the transmission section 19 to send out a negative response signal G1. This negative response signal G1 is sent to the terminal device 1 through the telephone line 2 and the exchange 3, and is received by the receiving section 20 thereof. Then, the control unit 5 causes the transmitting unit 12 to transmit data DT2 having the same content as the data DT1 again. When this data DT2 is also detected to be abnormal by the center device 4, a negative response signal G2 is sent out again and transmitted to the terminal device 1. Then, data DT3 having the same content as data DT1 is sent again to the center device 4, and if the data is determined to be normal, an acknowledgment signal K is sent. Then,
When this acknowledgment signal K is received by the terminal device 1, a termination signal S is sent to the center device 4, and the control section 5 roughly opens the closing section 8 and switches the switching section 6 to the telephone side. In addition, in the center device 4, the closing portion 15 is opened upon reception of the termination signal S.

[Problems with background technology]

However, in the above device, the data transmission direction is only one direction from the terminal device 11 to the center device [4], but in order to send out a response signal indicating whether the data is normal,
, a receiving section 20 must be provided. Therefore, the price of the valve device becomes high. Therefore, in order to avoid increasing the price of the device, there is a method in which the transmitter 19 and receiver 20 for transmitting a response signal indicating whether the data is normal are eliminated, and the same data is repeatedly transmitted multiple times. However, with this method, even if the same data is sent multiple times, there is no guarantee that the data will be sent accurately, and the data transmission time will only increase. , which is a fatal flaw.

[Object of the Invention] The present invention has been made based on the above-mentioned circumstances, and its purpose is to provide reliable and accurate data transmission without sending a response signal indicating whether the data is normal. The object of the present invention is to provide a terminal-originated transmission device with high performance.

[Summary of the invention]

In the present invention, when data is transmitted from a terminal device, the center device releases the telephone line if the data is normal, and if it is abnormal, connects the telephone line continuously to enter a data re-receiving state, while the terminal device The device is a terminal-originating type transmission device that attempts to achieve the above-mentioned purpose by retransmitting the data if a dial tone due to the release of the telephone line of the center device is not received after the data is sent.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of a terminal originating type transmission device.

The terminal device 30 is connected to a center device 50 via a telephone line 40 and an exchange 41. Although a plurality of terminal devices 30 are connected to the center device 50, only one terminal device is connected here. Terminal device 30
In particular, if a dial tone is not received even after a predetermined period of time has elapsed after data transmission, it has a function of transmitting the same data again. Specifically, a switching unit 31 is connected to the telephone line 40, and the switching unit 31 switches the terminal device 30 and the telephone 1a32 to the telephone line 40. One end of a coupler 34 is connected to this switching part 31 via a closing part 33, and an interface 35 is connected to the other end of this coupler 34. Transmission section 37
Data is exchanged between the telephone line 40 and the telephone line 40. Now, the i control unit 38 controls data transmission according to the program of the data transmission flowchart shown in FIG.
It has a function of transmitting data with the same content again if the dial tone detection section 36 does not receive the dial tone even after a predetermined period of time has elapsed.

On the other hand, the center device 50 receives the data after receiving the call signal from the exchange 41, judges whether the data is normal or not, and releases the connection with the telephone line 40 if the data is normal, or if there is an abnormality. If so, it has a function of continuing the connection with the telephone line 40 and waiting for data to be re-received. Specifically, the coupler 5 is connected to the telephone line 40 via the switching unit 51.
2 is connected to one end of the coupler 52, and an interface 53 is connected to the other end of the coupler 52. The receiving unit 54 is configured to receive data through this interface 53. Further, a calling signal detecting section 55 is provided on the telephone line 40 side of the switching section 51, so that a calling signal is detected and the detection signal is sent to the control section 56. Now, this control section 56
Data reception is controlled according to the program of the data reception flowchart shown in the figure. Specifically, data is received after receiving a call signal from the exchange 41, and it is determined whether or not this data is normal. telephone line 40
It has a function to release the connection to the telephone port 840 and, if there is an abnormality, to continue the connection to the telephone port 840 and to make it possible to re-receive data.

Next, the operation of the apparatus configured as described above will be explained according to the data transmission flowchart shown in FIG. 2, the data reception flowchart shown in FIG. 3, and the operation timing chart shown in FIG. 4. In FIG. 4, Aa indicates the operation of the terminal device 30, and Ba indicates the operation of the center equipment M50.

When a data transmission request occurs at time t10, the control section 38 of the terminal device 30 switches the switching section 31 from the telephone 8132 to the terminal device 30 side in step e1, and the closing section 33 is closed in step e2.

As a result, in step e3, the dial tone Ha from the exchange 32 is received by the dial tone detector 36 from the coupler 34 through the interface 35, and upon confirmation of the dial tone Ha, the control section 38 selects the tone from the transmitter 37 in step e4. Sends the signal @ (dial signal) D. This dial signal is sent from the telephone line 40 to the exchange 41, and from this exchange 41 is sent to the center device 50 as a call @Ya.

On the other hand, the center device 50 is in a state of detecting the calling signal Ya, and when the calling signal ya is input to the center device 50,
This is detected by the calling signal detection section 55 and a detection signal thereof is issued to the control section 56. This results in step f
1, the control section 56 closes the closing section 51 to enter the incoming call state (time t11).

Here, the control unit 38 of the terminal device @30 determines whether the center device 50 has entered the incoming call state in step e5 and determines that the center device 50 has entered the incoming call state at time t11.
At this point, data is sent from Yu. Note that step e6
If the center device 50 does not receive an incoming call for a predetermined period of time, it is determined that the time has elapsed and the process is terminated as an error.

Now, when the terminal device 30 enters the incoming call state, the terminal device 30 transmits the data DTa from the transmitter 37 in step e1. This data DTa is transmitted to the center device 50 via the telephone line 40 and the exchange 41. And the center device 5
0 coupler 52 and interface 53, and is received by the receiving unit 54 (step f2). By the way, when the data DTa is thus received in step f2, it is determined whether the data DTa is normal in the next step f3. Here, if it is determined that there is an abnormality, the process moves to step f4 and the reception state of the retransmitted data, that is, the closing unit 51
Keep it closed.

On the other hand, after sending the data DTa, the terminal @@30 moves to step e8 and is in the state of detecting the dial tone Ha-. Therefore,
At this time, since the center device 50 continues to be connected to the telephone line 40, the dial tone Ha- does not arrive. Therefore,
If the beep Ha- is not received for a predetermined period of time, that is, step e
In step 9, it is determined that the time has elapsed, and the process returns to step e7, where the data DTt having the same content as the data DTa is generated.
) will be resent. In the center device 50, this data DTb
is received, and the data DT is received in step f3 in the same manner as above.
If it is determined whether b is normal or not and again it is determined to be abnormal, the center device 50 keeps the closing part 51 in the closed state. Therefore, the terminal device 30 returns to step e7 and sends data DTc having the same content as data DTa.

Now, if this data DTc is received by the center device 50 and judged to be normal by the judgment in step f3, then
In step f5, the closing section 51 is opened by the control section 56. As a result, the telephone line 40 is released, and the dial tone Ha- is sent from the exchange 41 to the terminal device 30 and the center device 50. In this manner, the terminal device 30 receives the dial tone Ha- in step e8, so it moves to the next step e10, ell, opens the closing part 33, and then switches the switching part 31 to the telephone 32 side. This means that the data has been accurately transmitted.

Note that if data is transmitted several times and all of them are determined to be abnormal, the process moves to step e12 and ends with an error. Further, when the center device 50 is in the data receiving state (step f2), if no data is received for a predetermined period of time as determined in step f6, the closing portion 51 is opened and an error termination occurs.

In this way, in the above embodiment, when data is transmitted from the terminal device 30, the center equipment ff50 releases the telephone line 40 if the received data is normal, and closes the telephone line 40 if the received data is abnormal. On the other hand, if the terminal device 30 does not receive the dial tone Ha= due to the release of the telephone line 40 of the center device 50 after transmitting the data, the data is retransmitted, so that the data transmission direction is set to the terminal device. 30 to the center device 150, there is no need for a transmitting/receiving section for a response signal that is a result of determining whether the data is normal or not, and the telephone line 40 is necessary for telephone calls.
Data can be transmitted reliably and accurately using only the connection means and the like. Moreover, the center device M50 can also determine whether the data is normal or not, and can repeat the transmission until the data is transmitted normally. Therefore, the time required for data transmission can also be reduced. Roughly speaking, if data is not transmitted even after a predetermined period of time has elapsed, or if data is determined to be abnormal even after being transmitted several times, an error can be displayed, and the abnormality can be quickly notified.

It should be noted that the present invention is not limited to the above embodiment, and can be modified without departing from the spirit thereof. For example, the format of the transmitted data may be a frequency modulation signal (FSK), a multifrequency mixed signal (DTMF), or the like. Further, as the dial signal, a dial pulse may be generated by opening and closing the closing section 33, or a dial tone may be generated by the transmitting section 37.

〔Effect of the invention〕

As described in detail above, according to the present invention, it is possible to provide a highly reliable terminal-originated transmission device that can reliably transmit data without sending a response signal indicating whether the data is normal.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of a terminal origination type transmission device according to the present invention, FIG. 2 is a data transmission flowchart of the device of the present invention, FIG. 3 is a data reception flowchart of the device of the present invention, and FIG. The figure is an operation timing diagram of the device of the present invention, FIG. 5 is a configuration diagram of the conventional device, and FIG. 6 is an operation timing diagram of the conventional device. 3o...Terminal device, 31...Switching section, 33...Closing section, 35...Interface, 36...Tone detection section, 37...Transmission section, 38...Control section , 40・
...Telephone line, 41... Switchboard, 50... Center device, 51... Closing unit, 53... Interface,
54... Receiving section, 55... Calling signal detection section, 56.
...Control unit. Applicant's representative Patent attorney Takehiko Suzue Figure 1 Figure 2 1I 3 Prisoner

Claims (1)

[Claims] In a terminal transmission transmission device in which a terminal device and a center device are connected via a telephone line and data is transmitted in only one direction from the terminal device to the center device, the terminal device waits for a predetermined period of time after transmitting data. The center device has a function of retransmitting the data if it does not receive a dial tone, and the center device receives the call signal and receives the data from the terminal device, and if the data is normal, releases the telephone line. . A terminal-originating type transmission device having a function of maintaining the connection state of the telephone line and waiting for re-reception of the data if there is an abnormality.