JPS60236547A - Data communication controller - Google Patents

Abstract

PURPOSE:To reduce the hardware quantity and therefore to simplify the control of data communication by connecting the output of a selection circuit means which gives a selective action to a data transmission/reception control circuit to the input of a response propriety signal for data terminal of an interface and sharing a circuit selection register of a data communication controller. CONSTITUTION:When a circuit is selected at the side of a data terminal device DTE, an output of a high level is produced at an output terminal Q of a circuit selector LSL11. Then each element of a DTE transmission/reception control circuit 12 is activated to turn on a DTE propriety response signal ERT. Under such conditions, a network controller 4 sends a call display signal CI to a modulator/demodulator 3 when the controller 4 receives a call signal. The modulator/ demodulator 3 secures an AND between the signal CI and a signal ER given from a data communication controller 2 and sends a circuit connection command signal CML back to the controller 4. The controller 4 gives a reply to the signal CML and connects a subscriber circuit 5 to the modulator/demodulator 3. Then the controller 4 turns on the carriers with each other to perform the data communication.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical field of the invention The present invention relates to a data communication control device, and particularly to a network control device,
・Modulation and demodulation equipment, ・Data communication equipment when connecting data terminals through telephone lines (network control equipment, modemation equipment, etc.)
Hereinafter referred to as DCE. ) and data terminal equipment (hereinafter referred to as DT)
It is called E. ) to each interface connected to the DCE and connected to the DCE.
ER (f!quipmen) sent to the CE modem
The present invention relates to a data communication control device that improves the manner in which a tReady signal is generated.

(0) Technical background In the data communication system, the DCE and DT'E are each connected to a data communication control device through separate interfaces, and the data communication control device is connected to the data processing system. There is a format. This type of data communication system employs a configuration in which an ER signal for line connection and release control is sent from a data communication control device to a modulation/demodulation device for line connection and release control.

The means for generating the ER multiplied signal is simply provided as a separate component without any consideration for other components in the data communication control device, and the number of components increases accordingly.
This has led to complicated control, and there is a demand for the development of progressive solutions to this type of problem.

(C) Prior Art and Problems The conventional ER signal generating means is constructed so that a register provided exclusively for it in the above-mentioned data communication control device can be programmably controlled by a data processing system. Therefore, an increase in hardware is unavoidable, and provision for its control is also essential.

The present invention has been made in view of the technical problems faced by the conventional system as described above.The purpose of the present invention is to share the line selection register of a data communication control device, and to An object of the present invention is to provide a data communication control device that can enjoy a reduction in the amount of data and the accompanying simplification of control.

(G) Structure of the Invention And, in order to achieve this object, the device of the present invention includes a first interface for connecting a DCE and transmitting a DTE response availability signal to the modulation/demodulation device of the DCE, and a first interface for connecting the DTE. 2 interfaces, the first and second
In the data communication control device, the output of the selection circuit means is connected to the first interface of the data transmission and reception control circuit, and selection circuit means for causing selective operation of the data transmission and reception control circuit. This is configured by connecting to the DTE response availability signal input.

(F) Embodiments of the Invention The present invention will now be described in detail with reference to the accompanying drawings.

FIG. 1 shows a data communication system implementing the present invention, FIG. 2 shows an embodiment of the present invention implemented within the data communication system shown in FIG. 1, and FIG. 3 shows the main points of the embodiment shown in FIG. FIG. 3 is a diagram showing a partial configuration.

In FIG. 1, 1 is a data processing system, 2 is a data communication control device, 3 is a modulation/demodulation device, 4 is a network control device, 5 is a subscriber telephone line, and 100 is a data terminal device. A data processing system is constituted by a data processing device 1 and a data communication control device 2, and a D
In some cases, the data terminal equipment (DTE) 100 is connected to the telephone line via the CE, and in other cases, the data terminal equipment (DTE) 100 is connected directly to the data processing system. Note that a DTE response permission signal [hereinafter referred to as E R (Equipment Rea
dy ) signal. ] Line 6, call display signal (hereinafter referred to as
CI multiplication signal is abbreviated as CI. ) line 7, and line connection command signal (
Hereinafter, it will be abbreviated as CML signal. ) only line 8 is shown; other data lines and control lines are not necessary for the detailed description of the invention and are omitted for clarity of the drawing. When configuring a system as shown in FIG. 1, when DC and E are connected to the above-mentioned communication control device 2, the communication control device 2 is connected to the DTE from the DCE side. When a DTE is connected to the communication control device 2, the communication control device 2 needs to have an ink face in which five DCEs are connected when viewed from the DTE side.

Therefore, the configuration of the communication control device 2 according to the present invention will be explained with reference to FIG.

In FIG. 2, 10 is a control register programmably controlled by the central processing unit (not shown) of the data processing system 1. This register 10 includes various bits, including a line selection bit. There is a line selector (LS'L) 11. The LSL output 11A is connected to the DTE transmission/reception control circuit 12 and the DCE transmission/reception control circuit 1.
Connected to 3. Reference numeral 14 denotes an interface for DCE (simulating DTE, hereinafter referred to as DTE interface) connected to data communication control device 2, which receives the receive data signal (RD
The double signal is sent to the DTE transmission/reception control circuit 12, and the send data signal (SD double signal) from the DTE transmission/reception control circuit 12 is received and sent to the modulation/demodulation device 3.
This is for receiving A at its ER signal input 16 via an inverter 15 and sending it to the modulation/demodulation device 3 via a driver 17. 18 is D connected to data communication control bag W2
An interface for TE (which simulates DCE and is hereinafter referred to as DCE interface).
Send the SD double signal from E to the DCE transmission/reception control circuit 13,
The RD double signal received from the DCE transmission/reception control circuit 13 is for receiving and sending to the DTE. R from modem 3
receiver 19 of the D-times signal DTE interface 14;
The data is received by the data transmitting/receiving circuit 22 via the AND gate 20 of the DTE transmitting/receiving control circuit 12 and the OR gate 21, and the SD double signal from the DTE is received by the receiver 23 of the DCE interface 18, the AND gate 24 of the DCE transmitting/receiving control circuit 13, and the OR gate. 21 and then received by a data transmitting/receiving circuit 22. The SD double signal sent from the data transmission/reception circuit 22 to the modulation/demodulation device 3 is sent to the modulation/demodulation device 3 via the AND gate 25 and OR gate 26 of the DTE transmission/reception control circuit 12, and the driver 27 of the DTE interface 14, and is also emitted from the data transmission/reception circuit 22. The RD multiplied signal received by the DTE is sent to the DTE via the AND gate 28 and OR gate 29 of the DCE transmission/reception control circuit 13, and the driver 30 of the DCE interface 17. The LSL output 11A of the control register 10 is connected to the input knot circuit of the AND gate 20.25 and the OR gate 26 of the DTE transmission/reception control circuit 12, and the input knot of the AND gate 28 of the AND gate 24 of the DCE transmission/reception control circuit 13. circuit and or gate 2
Connected to 9.

The LSL is connected to the clock terminal C as shown in FIG.
, data signal terminal D, cent terminal S, reset terminal R1
and an output terminal Q, the flip-flop is configured such that when a clock pulse is supplied to its clock terminal C, an output signal determined according to a data signal supplied to the data signal terminal appears at the output terminal Q. (Same for each bit of the control register) In addition, the set terminal S
and a switch means for selectively changing the signal level supplied to the reset terminal R, such as a manual switch 31, is installed between the signal level supply terminals 32, 33 and the neutral 34 and the earth, depending on the set position of the manual switch. The configuration is such that an output signal determined by the output signal appears at the output terminal Q. The clock terminal C of LSLll is connected to an address detection circuit (not shown) which indicates that the control register 10 has reached an address within the address space for the various addressable components including the control register 10 that is being accessed. The output line 35, the read/write signal line 36, and the clock signal line 37 are connected to the output of a Nant gate 38'.

Next, the operation of the embodiment of the present invention having the above-described structure will be explained.

LSLII when the switch 31 of the LSLII configured as described above is placed in the neutral 34
The cent mode is a programmable set mode determined by control of the central processing unit. Therefore, DTE
When line selection is performed on the side, a high level output is generated at the output terminal Q of the LSLII, activating each element of the DTE transmission/reception control circuit 12, and inverter 15,
The ER double signal is turned on via the driver 17.

In this state, the subscriber connected to the subscriber line 5,
For example, when a call is made from a maintenance center and the network control device 4 receives the call signal, it is sent from the network control device 4 to the CI double signal modulation/demodulation device 3 . The modulator/demodulator 3 performs a logical product of the ER multiplied signal from the Ct multiplied signal data communication control device 2 and returns the CML signal to the network control bag W4. After the network control bag W4 responding to the CML signal connects the subscriber line 5 to the modem 3, they mutually turn on their carriers and start data communication.

After the required data communication is completed and the carriers are mutually turned off, the maintenance center side releases the line, while the data communication control device 2 updates the LSLI of its control register 10.
I is set off. Therefore, the ER multiplier signal is turned off, and the CML signal from the modem 3 to the network control device 4 is switched off, so that the network control device 4 releases the line.

In this way, when the TE side is selected, the LSL output IIA is at a high level, so the DCE side is not selected.
The DCE side is selected at the same time as the LSL output switches to low level.

Unlike this normal operation, if the subscriber maintenance center side becomes required to take action, the switch 31 is set to the terminal 33 side and the reset terminal R of LSLIO is set to a low level. A low-level ER multiplied signal is generated from the output terminal Q to perform fixed selection on the DCE side. By doing so, communication between the DCE side and the data communication control device 2 can be performed while allowing the activities of the maintenance center.

In addition, to perform fixed selection on the DTE side, switch 29
It is sufficient to send the signal to the terminal 32 side, set the set terminal S of LSLII to a low level, and generate a high level ER multiplied signal from the output terminal Q.

Additionally, according to the present invention, it is not necessary to provide dedicated hardware and control it in order to generate the ER multiplied signal, as in the past, so the amount of hardware can be reduced and the control can be simplified. I can figure it out.

In the above embodiment, an example was explained in which the LSL output signal level is fixed in the internal circuit of the LSL 11, but the output of the LSLII, the input of the DTE transmission/reception control circuit 12, the ER signal input 16, and The switch 31 may be configured to produce the same effect with the input of the DCE transmission/reception control circuit 13, or the switch 31 may be remotely controlled.

(g) Effects of the invention As described above, according to the present invention, ■Can reduce hardware, ■Enjoy simplified control, Effects such as this can be obtained.

[Brief explanation of drawings]

Figure 1 is a diagram showing a data communication system implementing the present invention, Figure 2 is a diagram showing a data communication system implementing the present invention.
1 is a diagram showing an embodiment of the present invention implemented within the data communication system of FIG. 1, and FIG. 3 is a detailed diagram of the main part of the embodiment of FIG. 2. In the figure, 2 is a data communication control device, 3 is a modem device, 11
12 is a line selector, 12 is a DTE transmission/reception control circuit, 13 is a DCE transmission/reception control circuit, 14.18 is an interface, and 31 is a switch. Figure 1 Figure 2

Claims (2)

[Claims] (1) A first interface for connecting a data communication device and transmitting a data terminal device response availability signal to the modem of the data communication device, and a second interface for connecting the data terminal device; In a data communication control device having a data transmission/reception control circuit separately connected to a second interface, and selection circuit means for causing selective operation of the data transmission/reception control circuit, the output of the selection circuit means is connected to the first interface. A data communication control device characterized in that it is configured to be connected to a data terminal device as an interface to signal whether a response is possible or not. (2) said selection circuit means comprising switch means for generating at least two output levels, said selection control being effected in response to a first of said at least two output levels; Claim 1, characterized in that the device is configured to fixedly cause the operation of the transmission/reception control circuit connected to the second interface in response to a second output level of the output levels. The data communication control device according to item 1.