JP2000003238A - Input and output terminal equipment for electronic equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the inexpensive input and output terminal equipment of an electronic equipment for efficiently using a terminal for both an input and an output. SOLUTION: A bi-directional input and output 12 is constituted of a transistor 121 and an input buffer 122, and the collector of the transistor 121 is connected with a terminal 111, and one input of the input buffer 122 is connected with the terminal 111. When a control signal from a transmission controlling part 13 is applied to the base of the transistor 121, the terminal 11 can be used as an output terminal. Also, the transistor 121 is made non-conductive, and a signal inputted to the terminal 111 is applied through the input buffer 122 to the transmission controlling part 13 so that the terminal 111 can be used as an input terminal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an input / output terminal device for electronic equipment, and more particularly to an input / output terminal device in which one terminal can be used for both input and output.

[0002]

2. Description of the Related Art To connect various electronic devices to each other, there are a method using a dedicated connector and a method using a dedicated terminal. The dedicated terminal is provided with an input terminal and an output terminal separately, and the input signal is connected to the input terminal, the output signal is connected to the output terminal, and so on.

FIG. 6 shows a conventional output unit, and FIG. 7 shows an input unit. The output terminal 1 and the input terminal 2 are provided with eight circuits, respectively. The output terminal 1 is connected to the output of the output driver 3, and the input terminal 2 is connected to the input of the input buffer circuit 4.

[0004]

The output terminal 1 and the input terminal 2 shown in FIG. 8 and FIG. 9 are usually provided collectively for each unit like eight circuits or sixteen circuits. However, in actual use, the required number of terminals varies, and a unit is prepared for connection for each input for input and for each output for output. For example, even when two inputs and five outputs are required, eight input units and eight output units have to be prepared. As a result, the terminals of the input unit and the output unit cannot be used efficiently, resulting in extra terminals and waste of cost and space.

SUMMARY OF THE INVENTION Accordingly, it is a main object of the present invention to provide an inexpensive input / output terminal device for electronic equipment in which terminals can be used for both input and output, and terminals can be used efficiently.

[0006]

SUMMARY OF THE INVENTION The present invention relates to an input / output terminal device for electronic equipment in which one terminal can be used as an input terminal and an output terminal, the output of which is connected to one terminal and the one terminal. And an input buffer circuit having one input connected to the one terminal and receiving a signal supplied to one terminal in accordance with a reference signal input to the other input. It is configured with.

[0007]

FIG. 1 is a diagram showing an entire configuration of an embodiment of the present invention. In FIG. 1, a master unit 10 and a plurality of terminal devices 11, 12,... 1n constitute a network, and data is serially and mutually transmitted between the master unit 10 and each of the terminal devices 11, 12,. . And each terminal device 11,
.. 1n input / output data in both directions by input / output control.

FIG. 2 is a block diagram of the terminal device shown in FIG. Terminal device 11 is a bidirectional input / output unit 1
2, a transmission control unit 13 and a transmission driver receiver unit 14. The bidirectional input / output unit 12 includes an open collector transistor 121 and an input buffer circuit 122.
The input of the collector of the transistor 121 and one input of the input buffer 122 are connected to the terminal 111, the emitter of the transistor 121 is grounded, and the base thereof is supplied with a control signal from the transmission control unit 13. Also, the other input terminal of the input buffer circuit 122 has
The reference voltage is supplied, and the output signal of the input buffer circuit 122 is supplied to the transmission control unit 13. The bidirectional input / output unit 12 includes, for example, eight circuits.

The transmission control unit 13 checks the serial data transmitted from the master unit 10 shown in FIG.
Output to the base. The transmission control unit 13 converts the parallel data output from the input buffer 122 into serial data, and outputs the serial data to the master unit 10 via the transmission driver receiver unit 14. The transmission driver receiver section 14 performs a transmission interface between the master unit 10 and the transmission control section 13. Note that the transmission control unit 13
When the transistor 121 is turned on, the buffer 122
The gate is closed so that the output of the device is not taken in, so that its own signal is not fed back.

Next, the operation will be described. Data is serially transmitted from the master unit 10 to each of the terminal devices 11, 12,... 1n via a transmission line. At this time, the data includes an identification code for identifying each terminal device. Terminal device 1 shown in FIG.
At 1, the serial data input from the transmission line via the terminal 112 is input to the transmission control unit 13 via the transmission driver receiver unit 14.

When the transmission control unit 13 determines that the data for identifying its own terminal device has been sent, it converts the subsequently input serial data into parallel data and supplies the parallel data to the base of the transistor 121. , Terminal 111 outputs data in parallel. When outputting the data input to the terminal 111 to the master unit 10, the transmission control unit 13 turns off the transistor 121. Then, when the input signal exceeds the reference voltage, the input buffer 122 supplies an output signal to the transmission control unit 13. The transmission control unit 13 converts the data input from the input buffer 122 into serial data, and transmits the data from the transmission driver receiver unit 14 to the master unit 1 via the transmission line.
Send to 0.

Therefore, in the embodiment shown in FIG. 2, the terminals of the terminal devices 11, 12,... 1n can be shared for inputting and outputting data.

FIG. 3 is a diagram showing another embodiment of the present invention. In the embodiment shown in FIG. 1 described above, data is serially transmitted between the master unit 10 and each of the terminal devices 11, 12,.
Is each sequencer, each CPU 100 and each terminal device 1
Data is transmitted in parallel between 10, 120... 1n0 by an external parallel bus.

FIG. 4 is a block diagram of the terminal device shown in FIG. The terminal device 11 shown in FIG.
0 indicates that the transmission control unit 130 controls the base of the transistor 121 in accordance with the signal from the external parallel bus, and outputs the signal received by the input buffer 122 to the external parallel bus, as compared with the terminal device 11 of FIG. Other operations are the same as those in FIG.

FIG. 5 is a diagram showing a specific example in which a light emitting diode and a switch are connected to the terminals of the terminal device shown in FIG.

In the example shown in FIG. 5A, the terminal 111 is used as an output terminal, and a series circuit of the resistor R1 and the light emitting diode LED is connected between the power supply and the terminal 111. Transistor 1 of device 11
By driving the LED 21, the light emitting diode LED is turned on.

FIG. 5B shows the case where the terminal 111 is used as an input terminal. A series circuit of the resistor R1 and the switch SW is connected between the power supply and the ground, and the connection point of the resistor R1 and the switch SW is connected to the terminal 111. It was done. When the switch SW is closed, an input signal is provided to the transmission control unit 13 via the input buffer 122.

FIG. 5C shows the case where the terminal 111 is used as an input / output terminal. The resistors R1 and R2 and the light emitting diode LED are connected between the power supply and the ground, and the connection point between the resistors R1 and R2 is connected to the terminal 111. And a switch SW is connected between the terminal 111 and the ground. In this example, the light emitting diode LED is lit when the transistor 121 is not driven and the switch SW is off. When the switch SW is closed, the light emitting diode LED is turned off, and a signal from the switch SW is input to the input buffer 122. When the switch SW is not pressed and the transistor 121 is driven, the light emitting diode LED
Turns off.

In the example shown in FIG. 5D, the resistor R1, the light emitting diode LED, and the switch SW are connected between the power supply and the ground, and the connection point between the light emitting diode LED and the switch SW is connected to the terminal 111. is there. When the switch SW is pressed, the light emitting diode LED is turned on and a signal is input to the input buffer 122. When the switch SW is not pressed and the transistor 121 is driven, the light emitting diode LED is turned on. As described above, since various input / output devices can be connected to the terminal 111, the terminal device 11 can be used for various purposes.

The examples shown in FIGS. 1 and 2 can be effectively applied to a picking system such as a warehouse. The picking system is a system that collects necessary materials from shelves based on shelf information and a delivery list managed by a computer, and circulates them.

FIG. 6 is an external view of the terminal 20 provided in the picking system. The terminal 20 has a 2-digit 7-segment display 2 for displaying the number of materials.
1 and a switch 22 for confirming that the material has been removed from the shelf. In order to connect this terminal 20 to the master unit, 14 signal lines of a 2-digit 7-segment display 21 and a switch 22
Requires one input line. This is a conventional general-purpose input,
If an output unit is to be used, 16 output units and 8 input units are required, resulting in two outputs and seven inputs remaining.
Wiring and power supply for each unit are required.

On the other hand, when the terminal device 11 shown in FIG. 2 is used, it is only necessary to prepare one unit having 16 circuits of the bidirectional input / output unit 12, thereby reducing the cost, facilitating the wiring, The effect of power saving can be achieved.

FIG. 7 is a diagram showing a harness checker using the present invention, and is used, for example, to check a complicated transmission harness of an automobile.

In FIG. 7, transmission control units 31, 32, 3
3, a corresponding transistor 41, 42, 43 and an input buffer 51, 52, 53 are connected. A collector of the transistor 41 and one input of the input buffer 51 are connected to a terminal 61. One input of buffer 52 is connected to terminal 62, and the collector of transistor 43 and one input of input buffer 53 are connected to terminal 63. The input buffers 51, 52,
The other input of each of the 53 is supplied with a reference voltage.

Now, a harness is connected between the terminals 61 and 62 and between the terminals 61 and 63 with the terminal 61 set to the output side and the terminals 62 and 63 set to the input side by the transmission control unit 31. Under the control of the transmission control unit 31, the transistor 4
When the input buffers 52 and 53 are able to determine that the state of the terminals 62 and 63 has changed by turning ON the harness 1, it can be determined that the harness is normal. The input / output can be set arbitrarily even if it is changed to another harness. If the maximum number of connection points is prepared, it is possible to check the harness of any pattern by setting the input / output.

[0026]

As described above, according to the present invention, the output of the driver circuit and the input of the input buffer are commonly connected to one terminal, and when used as an output terminal, the driver circuit is driven. By operating the input buffer when using the terminal, one terminal can be used also as an input terminal and an output terminal, and an inexpensive input / output terminal device that can use terminals efficiently can be realized.

[Brief description of the drawings]

FIG. 1 is a diagram showing an overall configuration of an embodiment of the present invention.

FIG. 2 is a block diagram of the terminal device shown in FIG.

FIG. 3 is a diagram showing a configuration of another embodiment of the present invention.

FIG. 4 is a block diagram of the terminal device shown in FIG. 3;

FIG. 5 is a diagram showing a specific example of a case where a light emitting diode and a switch are connected to terminals of the terminal device shown in FIG. 2;

FIG. 6 is an external view of a terminal device according to an embodiment of the present invention applied to a picking system.

FIG. 7 is a diagram showing a harness checker using one embodiment of the present invention.

FIG. 8 is a diagram showing a conventional output unit.

FIG. 9 is a diagram showing a conventional input unit.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Master unit 11,12 ... 1n, 110,120 ... 1n0 Terminal device 12 Bidirectional input / output part 13,31,32,33,130 Transmission control part 14 Transmission driver receiver part 61,62,63,111 Terminal 41,42 , 43, 121 Transistors 51, 52, 53, 122 Input buffer

Claims (1)

[Claims] 1. An input / output terminal device for an electronic device that can use one terminal as an input terminal and an output terminal, wherein an output of the driver is connected to the one terminal and a signal is output to the one terminal. And an input buffer circuit having one input connected to the one terminal and receiving a signal supplied to the one terminal in accordance with a reference signal input to the other input. Input / output terminal device.