JPS59100948A - Communication circuit system - Google Patents

Abstract

PURPOSE:To share a communication circuit and to connect with switching plural terminal devices to a host processor by detecting a terminal switching signal by the host processor and connection switching device provided among plural terminal devices and discriminating the terminal device. CONSTITUTION:The data signal and the terminal indicating signal supplied from a host processor are supplied to a serial-parallel converting part SP of a terminal switching part K from a terminal T1 via a communication circuit of a single system and an MODEM M'. These signals are converted into parallel data signals and supplied to registers R1 and R2. The terminal indicating signals ESC and DCn (n=1, 2) stored in the registers R1 and R2 are detected at a detecting part F, and the terminal device to be selected is discriminated. Then switching signals are transmitted to a switching circuit J1 and a switch J2. If a display device TM1 is selected, the data signal is displayed to the device TM1 from the data signal D1 following the terminal indicating signal via the circuit J1, a register R3 and a parallel-serial converting part PS1 respectively. If a sound output device TM2 is selected, the data signal is delivered via the circuit J1, a register R4 and a parallel-serial converting part PS2.

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Technical Field of the Invention The present invention relates to a communication line 7 system in which a host computer and a plurality of terminal devices are connected via a communication line.

(BJ Technology Background In order to make effective use of electronic nasal meters, multiple terminal devices are connected to one post-processor, and between these terminal devices,
Exchanging data is widely practiced.

Particularly in the field of facsimile, it is desirable to connect a host processor and a terminal device via a communication line to make effective use of the communication line.

(0) Prior Art and Problems As shown in Figure 1, in the past, the host processor H has two communication lines, and these are connected to terminal devices TM, TM2, respectively.
is connected.

Each of these communication lines is connected to a communication line adapter A1, A2.
Modem MI + Ml' + M! t M,l are connected.

Data is exchanged between the terminal device TM and the host processor H using an adapter AI that has functions for starting and stopping the transmission and reception of data to be transmitted and received, and a function for adding parity bits.
, via a modem M12M1' that modulates and demodulates data.

Similarly, data is exchanged between the terminal device TM and the host processor H using the adapter A1. This is done via modem M2 + M2'.

However, in such a system, since a communication line is provided for each terminal device, the system becomes large and the communication line cannot be used effectively.

(D) Purpose of the Invention The present invention was made in view of the above-mentioned drawbacks of the prior art, and an object of the present invention is to provide a communication line system that can share a communication line and switch and connect a plurality of terminal devices to a host converter. do.

(1) Structure and object of the invention According to the present invention, in a communication line system comprising a host processor and a plurality of terminal devices connected to the host processor via a communication line, the host processor A terminal device connection switching device is provided between the terminal device and the plurality of terminal devices, and the terminal device connection switching device includes a register for storing data sent and received via the communication line, and a terminal device connection switching device for terminal switching based on the data stored in the register. A communication device comprising: a detection unit that detects a signal and determines a terminal device specified by the terminal switching data; and a switching unit that switches and connects the line based on the output of the detection unit. This is achieved by providing a line system.

(F) Examples of the invention Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 82 is a configuration diagram of an embodiment of the present invention, in which parts equivalent to those in FIG. 1 are given the same reference numerals.

In FIG. 2, A is a communication line adapter.

M' is a modem, and K is a terminal switching section.

The terminal device at TMt*TMt is a display device and a speech synthesizer.

FIG. 3 is a configuration diagram of the switching section.

from the host processor via modem M' to terminal T1.
The terminal instruction signal and data signal inputted manually are input to the serial/parallel converter sp and converted into parallel data signals.

The signal is a terminal instruction signal gs as shown in FIG.

and Do, or DC, and data signal DI+D! ...
...consists of Dn.

These signals ff1s O, DOn(n-1, 2), D
, D2 . . . Dm are changed in parallel and input to registers R1 and R2, respectively.

Of these, registers R, , R2 have terminal instruction signals FISe.
.

When Dom(n-1, 2) is stored, it is detected by the detection unit F, which terminal device is determined to be selected, and a switching signal is sent to the switching circuit J1 and the switching device J2.

First, when the display device TM is selected, the data signal D following the terminal instruction signal first passes through the switching circuit J.
I is input to register R8, and data signal D2 is input to register R1. Note that the terminal instruction signal is not output from the terminal switching section K.

The data signal is transferred to the terminal device side in units of clock cycles, converted into a serial signal by the parallel-to-serial converter ps1, and appears at the terminal Tt. This data signal is transmitted to the display device TM,
is input to and displayed.

On the other hand, in this case, the switch J2 is switched under the control of the detector F so that the terminal T3 on the display device side and the terminal T4 on the modem M' side are connected. Accordingly, the operator can input a new request signal to the host processor H via the keyboard via the terminal T3+switcher J2r terminal 'I4 in response to the display by the data signal output from the host processor H.

In response to this request signal from the terminal device side, the host processor H transmits a new data signal by the above-described operation.

In this way, the host processor H and the display device gTM,
Signals are exchanged between the two.

Note that the same operation can be used to connect the audio output device TM and the host processor H, and the terminal instruction signal [k30. If a signal for selecting the audio output device d'rm* is used as Don (n=1, 2), the signals stored in the registers R, , R, will be transferred to the switching unit J.

The signal is inputted to register R4+parallel-serial converter Pa through register R4, where it is converted into a serial signal and appears at terminal T.

This signal enters the audio output device TM and is output as audio.

In this case, the switch J2 is connected to the audio device TM, and the audio output end signal is sent to the terminal T6. Cut mdiJ
The signal is transmitted to the host processor H via the 21 terminal T4.

Note that L is a clock signal source, and N is a register R1-R4+serial-to-parallel conversion circuit SP that receives the clock signal.

Instruction No. 16 in the parallel-to-serial conversion circuits PS, PB, is a control unit that controls the transfer of data signals.

(G) Detailed Description of the Invention As described above, the communication line system according to the present invention can switch and control line connections by signals sent and received between the host processor and the terminal devices, so that many terminal devices can be connected to the same terminal. It can be connected to the host processor using a line, simplifying the system configuration.

[Brief explanation of the drawing]

FIG. 1 is a conventional system configuration diagram, FIG. 2 is an embodiment configuration diagram of the present invention, FIG. 3 is a configuration diagram of a switching section, and FIG. 4 is a signal configuration diagram.

Claims (1)

[Claims] In a communication line system comprising a host processor and a plurality of terminal devices 6 connected to the host processor via a communication line, a terminal device connection switching device is provided between the host processor and the plurality of terminal devices, The terminal device connection switching device has a register that valves the communication line and stores data to be sent and received, and a terminal switching signal that is generated from the data stored in the register and a terminal switching device that uses the terminal switching data. 1. A communication line system comprising: a detection unit that determines a designated terminal device; and a switching unit that switches and connects the line based on the output of the detection unit.