JPS61199353A - Communication line interface - Google Patents

Abstract

PURPOSE:To improve the operability in using one of plural independent input/ output ports with plural functions in common by adopting the constitution that ports used in common by plural functions are set only with switch changeover. CONSTITUTION:A selector 9 connects an input/output controller 6 for X mode and a communication line interface connector 3 depending on the selecting condition given by a switch 10 or connects an input/output controller 2 for Y mode and the connector 3. The switch 10 is effective for the X mode only and has no function to give the selection condition for the Y mode. Thus, the controller 6 is not connected to the connector 3 at the Y mode and the connectors 3, 7 are used independently of each function.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a communication line interface suitable for connecting a multi-function system to a communication line.

[Technical Background of the Invention] Conventionally, multi-functional systems have been used, for example, in one system to perform office computer functions (hereinafter referred to as Y mode, ball).
It has a personal computer function (hereinafter referred to as X mode) and a communication line interface corresponding to each mode.

FIG. 4 is a block diagram showing an example of the communication line interface of a conventional multi-function system of this type. (modulator/demodulator) 4. X on 5 on CPtJPt
The mode serial input 7/' output controller 6 is connected to a modem 8 or other equipment via a communication line interface connector 7.

[Problems with Background Art] By the way, there is no problem if the ports installed independently on the NCP and CPIJ boards 1 and 5 are used individually for each function. However, if you want to use these ports in common, for example if you want to connect both ports to the same host computer system, etc., if the ports are independent as described above, you will have to reconnect the cable each time, Alternatively, countermeasures such as having two modems are required, which often has the drawback of being extremely difficult to use.

OBJECT OF THE INVENTION] In view of the above drawbacks, an object of the present invention is to provide a communication line interface that improves operability when one of a plurality of independent input/output ports is used in common for a plurality of functions. It's about doing.

[Summary of the Invention] The present invention provides a communication line interface that has a plurality of input/output ports corresponding to each function of a multifunctional system and connects these input/output ports to a communication line. signal selection means for connecting one or more of the data transmission and reception lines to data transmission and reception lines corresponding to a plurality of functions; It is preferable that the above object is achieved by including a selection condition signal generating means for outputting a signal that disturbs the operation connected to one or more input/output ports.

[Embodiment of the Invention] An embodiment of the present invention will be described below with reference to the drawings, in which the same parts as those of the conventional example are given the same reference numerals. FIG. 1 is a block diagram showing an embodiment of the communication line interface of the present invention. The X-mode serial input/output controller 2 is connected to a communication line interface connector 3 via a selector 9. The X-mode serial input/output controller 6 is connected to a communication line interface connector 7 and also to the communication line interface connector 3 via a selector 9. Communication line interface connector 3 is connected to modem 4, and communication line interface connector 7 is connected to modem or other equipment 8. A switch 10 for providing selection conditions is connected to the selector 9. Note that the NCR board 1 is equipped with a port for office computer functions, and the CPU board 5 is equipped with a port for personal computer functions.

The switch 10 provides selection conditions to the selector 9.

The selector 9 performs an operation of connecting the serial input/output controller 6 for the X mode and the communication line interface connector 3, or connects the serial input/output controller 2 and the communication line interface connector 3 for the Y mode, depending on the above selection conditions. .

It is assumed that this function is valid only in the X mode in which the switch 10 system is used as a personal computer, and that there is no function to provide selection conditions in the X mode in which the switch 10 system is used as an office computer. Therefore, in X mode, the X mode serial input/output controller 6 is not connected to the communication line interface connector 3, and each communication line interface connector 3, 7 is used independently for each function. It will be done.

FIG. 2 is a block diagram showing a detailed example of the communication line interface shown in FIG. 1. Here, the selector 9 shown in FIG. 1 is shown divided into a selector 91 for transmitting signals and a selector 92 for receiving signals.

FIG. 3 shows the selector 91 and
This is an example of a logic circuit for creating a selection condition signal outputted to 92. This logic circuit consists of Nant gate 11 and Noah gate 2.
1 and a switch 10.

Next, the operation of this embodiment will be explained. Here, it is assumed that the selectors 91 and 92 connect the communication line interface 3 side to the CPU 5 side when the selection condition signals SEL and R3EL are at low level. One input of the Nant gate 11 in FIG. 3 is always at a high level due to the voltage VCC. Further, when the system operates as a personal computer, the X mode signal 500 becomes high level, and the other input of the Nant gate 11 becomes high level. Therefore, the output of the Nant gate 11 becomes low level. In this state, when switch 10 is turned to side A in the figure, R3
The EL output signal line is grounded, and the selection condition signal RSEL becomes low level. Therefore, the selector 92 selects the received data 100 on the communication line interface connector 3 side and sends it to the CPU board 5 side. switch 1
When 0 is turned to the A side, the signal line connected to one input of the NOR gate 21 becomes high level, so the output signal of this NOR gate 21 becomes low level. Therefore, since the selection condition signal TSEL signal is also at a low level, the selector 91 selects the transmission data 200 on the CPU board 5 side and outputs it to the communication line interface connector 3. In this way, when the system operates in the X mode and the switch 10 is switched to the A side, the communication line interface connector 3 can also be used for the personal computer function.

Further, when the switch 10 is switched to the open side, the selection condition signal R3EL becomes high level, and the output signal TSEL of the NOR gate 21 also becomes high level.

Therefore, the selector 91 selects and outputs the transmission data 300 on the NCP board 1 side, and the selector 92 selects and outputs the transmission data 400 on the communication line interface connector 5 side.
is selected and output to the CPU board 5 side. That is,
At this time, the communication line interface connectors 3 and 5 are used independently for each function of the office computer personal computer.

Further, in both of the above states, if the system is no longer in the X mode, the X mode signal 500 becomes low level and the output of the Nant gate 11 becomes high level.

Therefore, the output of the NOR gate 21 is always at a high level, and the selector 91 always selects the transmission data 300 on the NCR board 5 side, making it impossible to share the communication line interface connector 3.

According to this embodiment, the communication line interface connector 3 can be shared by both the office computer and the personal computer by simply switching the switch 10.
When both of the above functions are used by connecting to one communication line through one port, the operability can be significantly improved.

``Effects of the Invention'' As described above, according to the communication line interface of the present invention, a port that can be used in common for multiple functions can be set simply by switching a switch, thereby allowing multiple independent input/outputs. This has the effect of improving operability when one port is shared by multiple functions.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing one embodiment of the communication line interface of the present invention, Fig. 2 is a block diagram showing a detailed example of the circuit shown in Fig. 1, and Fig. 3 is a block diagram showing a detailed example of the circuit shown in Fig. 2. FIG. 4 is a block diagram showing an example of a conventional communication line interface. 2.6...Serial input/output controller 3.7...
・Communication line interface connector 4.8...Modem 9.91.92...Selector 10...Switch 11...Nant Gate 21...Noah Gate agent Patent attorney Noriyuki Chika (and 1 other person) Figure 1 Figure 2

Claims (1)

[Claims] In a communication line interface that has a plurality of input/output ports corresponding to each function of a multifunctional system and connects these input/output ports to a communication line, one or more of the plurality of input/output ports can be used for multiple functions. a signal selection means connected to a data transmission/reception line corresponding to the signal selection means;
and selection condition signal generating means for outputting a signal that selects a specific data transmission/reception line among the data transmission/reception lines and connects it to the one or more input/output ports. A communication line interface featuring: