JPS60226253A - Data terminal ready signal generating system - Google Patents

Abstract

PURPOSE:To generate simply and easily a data terminal ready signal by allowing a data terminal equipment to generate the data terminal ready signal from a called party display signal and a reception carrier detecting signal from a line terminator in a data terminal equipment. CONSTITUTION:The data terminal equipment DTE3 stores the called party display signal CI from an automatic incoming line terminator DCE2 at a one-shot multivibrator 2 for a prescribed period so as to generate the data terminal ready signal ER. After the DCE2 detects the carrier detecting signal CD, the signal CD from the DCE2 is used as it is as the signal ER. The signal ER is returned from the DTE3 to the DCE2 from the start of the CI to the end of communication.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention 3] The present invention relates to a data terminal ready signal generation method in a data terminal device connected to an automatic call termination type data line termination device. The present invention relates to a data terminal ready signal generation method that easily generates a data terminal ready signal using a called indication signal and a data channel received carrier detection signal from a receiver.

[Background of the invention j Generally, data line 1m termination equipment (hereinafter referred to as DCE) is implemented by a network control equipment (NCtLJ, modem equipment (MODEM), etc.), and is located in the same position as a telephone in a switched network. The connection between the line and the data terminal equipment (hereinafter referred to as DTE) is established over a switched network.Automatic termination type DCE automatically responds to a call (incoming signal) from the switched network. It is used to set up switching network lines. The D'I'E connected to the auto-terminating DCE is the
If the data terminal ready signal (hereinafter referred to as the ER double signal) is not returned in response to the called indication signal from the CE (hereinafter referred to as the CI double signal), the DTE does not respond to the call and the E
When the R signal is turned off, it functions to automatically restore the line.

Until now, whether or not a DTE is in an operable state, that is, a ready state, requires not only its hardware but also its software to be in a ready state.Generally, these states are monitored by software, and both of them are in a ready state. The reality is that the ER multiplied signal is generated and sent for the first time in a certain case. The end of communication is also detected by the software, but if the ER signal is to be generated and sent out by software, a control program is required for that purpose, and if the software processing is unnecessarily burdened, problems may occur. be.

[Purpose of the invention]

Therefore, it is an object of the present invention to provide a data terminal ready signal generation system that can easily generate an ER multiplied signal using wiring logic without imposing a burden on software processing.

[Summary of the invention]

For this purpose, the present invention provides automatic termination type DCH in DTE.
The CI double signal from the DCB starts to return the JER signal, but the return is held for a certain period of time until the data channel reception carrier is detected in the DCRt, but after that, the data channel reception carrier detection signal from the DCB starts. The signal is directly multiplied by ER and sent back to D(l).

The ER double signal DCE must be returned to 9D C11l from the time the CI double signal is received until the end of the communication, but as a general rule, when using an automatic call receiving type as the DCB. When the line is restored from the calling side, the receiving side can recognize that communication is in progress (by detecting the data carrier). Therefore, the data carrier detection signal can be used as is for controlling the termination of the EtR signal.

[Embodiments of the invention]

The present invention will be explained below with reference to FIGS. 1 and 2.

FIG. 1 shows the internal structure of the main part of an example of D'['E according to the present invention in relation to DCE).

FIG. 2 shows signal waveforms of examples of various signals exchanged between the DTEI and DCE.

As shown in the figure, the DT 13 according to the present invention includes a one-shot circuit 4 triggered by the rising edge of the CI double signal, and an output from the one-shot circuit 4 and a data channel reception carrier detection signal (hereinafter referred to as CD) from the DCB 2. signal)
The output of the OR circuit 5 is multiplied by BR and sent back to the DCE.

When there is an incoming call from @1 to the DCE2, the DCB2 is busy sending out a CI double signal to the DTE5, thereby notifying that there is an incoming call. In the DTE 5 that receives the CX signal, the one-shot circuit 4 is triggered at the rising edge of the signal, and the CI' signal as the trigger output is sent back to the DCB 2 as an ER multiplied signal via the OR circuit 5. be. Upon receiving the ER double signal, DCB 2 responds to the incoming call, connects the line, and then receives the data carrier from the originating station.

If a data carrier is detected, the CD during the detection period.
The signal is then sent to the DTE3.

By the way, the CI' signal is generated over a certain period of time, and since the certain period of time is set to be longer than the time it takes for the line to be connected and the data carrier to be detected, the CI' signal is generated. A 1 ccD signal will be obtained before the generation ends. That is, even if the C signal no longer exists, the CD signal continues to be sent back to the DCIi 12 as an ER multiplied signal via the OR circuit 5. When the communication ends and data carrier transmission from the other station stops, the CD signal to DTE5, and therefore the ER double signal D
The signal is no longer sent to CB2, and as a result, 9DCFt2 has to restore the line for the first time.

〔Effect of the invention〕

As explained above, the present invention has the advantage that the DTE can easily generate the BR multiplied signal based on the CI multiplied signal and the CD signal from the DCK.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the internal configuration of the main parts of an example of the DTP according to the present invention in relation to DCEIfC, and FIG.
'[' is a diagram showing signal waveforms of examples of various signals exchanged between E and DCI. 2...DCE (data line terminal equipment), 3...DT
E (data terminal device) S4...One-seat cut circuit, 5
...Akio Takahashi, Patent Attorney for OR Circuit, Figure 1, Section 2

Claims (1)

[Claims] Data terminal ready, where the data terminal device generates a data terminal ready signal to be sent back to the automatic termination type data line termination device based on a called indication signal sent from the automatic termination type data line termination device when there is an incoming call. This is a signal generation method in which data terminal equipment uses a fixed time width that lasts at least from the rise of the called indication signal until after the automatic termination type data line termination equipment detects a data carrier from the other station. A new called indication signal is generated by hardware, and a data terminal ready signal is generated by a hardware-wise OR of this signal and a data channel reception carrier detection signal from the automatic incoming data line termination device. Characteristic data terminal ready signal generation method.