JPH03100805A - Data/input/output system for programmable controller - Google Patents

Abstract

PURPOSE:To decrease the number of connection signal cables and connectors by sharing input and output interface parts and transmitting the parallel input/ output data in time division via an external shared data transmission line connected to both interface parts. CONSTITUTION:The input and output interface parts are shared and an external shared data transmission line C is connected to a shared interface part (c). Simultaneously, a thumb-wheel switch 5 and an LED numerical display device 6 are connected to the line C. Then an input/output selection switch 21 is operated and simultaneously the parallel input or output data are transmitted in time division. Consequently, the number of input/output data transmission lines is halved. Furthermore the data transmission line can be immediately connected to the interface part with no hesitation regardless of the application for input or output signal. Also, just a single pair of connectors suffice is used.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a data input/output method for a programmable controller.

[Conventional technology]

In the programmable controller (hereinafter referred to as PC), as shown in Figure 2, -a is provided with an input circuit A that takes in an external parallel data signal and an output circuit B that outputs the external parallel data signal. .

The example shown in Figure 2 is 2 baud) RAM22, RA
M 23, ROM 24, CPU 25, input data buffer circuit 26, output data latch circuit 27, select signal latch circuit 28, output signal select signal latch circuit 2
9 and a timing signal generator 30 are connected to the output terminal of the PC main body 1, -
The input data signal is taken in through the dedicated input data transmission line 3 connected to the input data buffer circuit 26 via a photocoupler FC, and the output data signal is connected to the output data latch circuit 27 via the photocoupler FC. The data is transmitted to the other device via a dedicated output data transmission line 4.

Note that 5 is a thumbwheel switch connected between the input data transmission line 3 and the select signal latch circuit 28 via a photocoupler FC, and 6 is a thumbwheel switch connected between the output data transmission line 4 and the select signal latch circuit 29 via a photocoupler FC. This is an LED numerical display connected to the

[Problem to be solved by the invention]

However, this configuration adopts a format in which independent circuits are provided for input data signals and output data signals, so terminals or connectors for interface with input/output data signals are provided separately for input a and output a. , and a separate signal cable was also required to connect it.

Therefore, the present invention provides a data input/output method that makes it possible to reduce the number of signal cables (data transmission lines) for connection with external equipment, reduce the number of interface terminals or connectors, and makes handling easier for the user. This is what I am trying to propose.

[Means to solve the problem]

The present invention has been made to solve the above-mentioned problems, and the input interface section and the output interface section of a programmable controller are shared, an external shared data transmission line is connected to the shared interface section, and the external common data transmission line is connected to the shared interface section. Parallel input data or parallel output data is transmitted in a time-division manner using a shared data transmission line.

[Effect]

In the present invention, the input interface section and the output interface section are shared, and an external common data transmission line is connected to the common interface section, so the number of input/output data transmission lines is halved, and the data It does not matter whether the transmission line is connected to the interface section for input signals or output signals.

〔Example〕

FIG. 1 shows an embodiment of the present invention □, and the same parts as the conventional device shown in FIG. 1 are given the same reference numerals.

The embodiment shown in Fig. 1 is an example in which PCC main body colors 10 modules 2° are connected, similar to the conventional example shown in Fig. 2, and the input/output with the PCC main body colors 10 modules 2° is connected. Data exchange is performed via a two-button RAM 22, and switching between selecting an interface with an external device for input or for output is performed by an input/output selection switch 21←.

The difference from the conventional device shown in FIG. 2 is that the input interface section and the output interface section are shared, an external common data transmission line C is connected to the common interface section C, and the thumbwheel switch 5 and LED
The point is that both the numerical display devices 6 are connected to the external common data transmission line C.

By operating the input/output selection switch 21 and transmitting parallel input data or parallel output data in a time-division manner, it is possible to perform the same functions as the conventional device shown in FIG.

〔Effect of the invention〕

As described above, according to the present invention, since the external connection section for input data and the external connection section for output data are made common, connection with external equipment can be made using the same cable for input and output.

This makes it possible to reduce the number of connection cables with external devices and reduce wiring costs.

In addition, since the module can be used for either input or output depending on the user, any combination of input and output can be made, and one module can be used efficiently.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention, and FIG. 2 is a block diagram of a conventional device. l... PC main body 2.2'... 10 modules 3... Input data transmission line 4... Output data transmission line 5... Thumbwheel switch 6... LED numerical display 21... Input/output selection switch 22...2 baud) RAM 23...RAM 24...ROM 25...CPU 26, 27, 28, 29, 30, 31, A, B, C, C+, input data buffer Circuits/Output data latch circuits/Select signal latch circuits for input signals/Select signal latch circuits for output signals/Timing signal generator/Select signal latch circuits for input/output signals/Input circuits/Output circuits/External shared data transmission lines/Connectors

Claims (1)

[Claims] The input interface section and output interface section of the programmable controller are shared, an external shared data transmission line is connected to the shared interface section, and parallel input data or parallel output data is time-divided using this external shared data transmission line. A data input/output method for programmable controllers that is characterized by data transmission.