JPS6072001A - Input/output device for controller - Google Patents

Abstract

PURPOSE:To execute easily an interface to a process and to reduce a cost of a controller by providing a switching circuit part, an A-D converting part and a D-A converting part. CONSTITUTION:An A-D converting part 5, a D-A converting part 7, a switching curcuit part 6, etc. are provided on a substrate. Each inputted signal S11-S13 is led to the switching circuit part 6 through an inputting circuit part 2 and an insulating circuit part 3, respectively, led directly to an internal controlling circuit part 4 at its one switching position, and led to the internal controlling circuit part 4 through the A-D converter 5 at the other switching position. This circuit part 4 operates as an interface circuit to its external operating part, this circuit and the external operating part are connected through a data bus 9 and a control bus 16, and a data formation processing is executed. In this regard, said switching circuit 6 determines a switching position by whether signals from input/output circuit parts 2, 8 are digital or analog, and etermines which of both the converters is made to pass through.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an input/output device for a controller used, for example, as an interface between a controller and a process.

[Technical background of the invention]

Conventional input/output devices for controllers are mainly designed for large-scale processes, and are classified into analog input boards, digital signals, input, and output, respectively.

An input/output device is constructed by storing module boards with functions such as an analog output board, a digital input board, and a digital output board, as many as necessary for the process or in a controller 7, or the like.

On the other hand, small-scale processes.

In particular, the input/output devices used in processes such as the Wanrusi controller rarely exist independently as input/output devices, and are often installed on the same board together with arithmetic units, control units, storage devices, etc. It is configured as a one-zade type.

[Problems with background technology]

Therefore, in particular, one-loop controllers used in small-scale processes have to design various boards each time according to the number of input/output points, which reduces design efficiency and ultimately makes the controller expensive.

When the above-mentioned input/output module board with divided functions is applied to a one-loop controller, there is no need to design each time, but on the other hand, the number of input/output points is considerably larger than the required number of input/output points, Since the controller is mounted on a physical board, there is a drawback that the size of the controller itself increases. In this case, an excessive number of idle input/output points are generally installed, which also increases costs.

[Purpose of the invention]

The present invention has been made in consideration of these problems, and is an input/output device for a controller that is cost-effective and has good performance, and is suitable for interfacing with a process that has a relatively small number of input/output points, such as a one-loop controller. The purpose is to provide the following.

[Summary of the invention]

To achieve the above object, the present invention provides at least one A-D converter and at least one D-converter provided for a plurality of input/output signal lines formed on the same substrate.
Depending on the A converter and whether the input/output signal is a digital signal or an analog signal, the incoming signal may be transmitted straight or
This is an input/output device for a controller, which includes a switching circuit section that switches for each input/output signal line whether to transmit through the A-D converter or the DA converter.

[Embodiments of the invention]

Hereinafter, the present invention will be explained in more detail according to Examples.

1, 2, 3, and 4 show an embodiment of the present invention. On the board l, there is an input circuit section 2.
．． Insulated circuit section 3. Internal control circuit section 4゜A-D conversion section 5,
Switching circuit section 6. A D-A converter section 7° output circuit section 8 is provided. The input circuit section 2 is provided with surge absorption means, etc., and the signals 81 , 82 , 8 input thereto are
3 indicates each insulation circuit 3 of the insulation circuit section 3 for each signal.
1 , 32 , and 33 to the changeover switches 61 , 62 , and 63 of the switching circuit section 6 . Each insulation circuit 31
, '32, and 33 are composed of photocouplers, isolation transformers, and the like, and electrically insulate signals from each other, and adjust signal levels in some cases. When each of the changeover switches 61 to 63 is set to one of the switching positions (upper side in the figure), the signals from the insulation circuit section 3 are directly transmitted to the internal control circuit section 4.
, and when it is set to the other switching position (bottom 1itl in the figure), the signals from the insulation circuit section 3 are sent to the A-D converter 51.
, 52 and 53 to the internal control circuit section 4. A-
The D converters 51 to 53 are included in the A-D converter 5 and are used to match the input signal to the input circuit 2, which is input as an analog or digital signal, to the format of the processed signal in the internal control circuit 4. It is provided. The internal control circuit section 4 can have both a digital type and an analog type circuit system, but here it is assumed that it is a digital type, and has a calculation section externally. The explanation will proceed assuming that it acts as an interface circuit between. In connection with this, each changeover switch 61
~63 is.

If the input signals 811-813 are digital, for example, a binary signal generated by turning off/off contacts, they are switched to the direct side without an A-D converter, and if they are analog, they are switched to the side with an A-D converter. Thus, the input signal Sll~S1
Regardless of whether 3 is digital or analog, a unified digital signal is introduced into the internal control circuit section 4. Note that the switching circuit section 6 sends an additional switching signal to the internal control circuit section 4 indicating which side the valley selector switch is switched to, and depending on the switching signal, the internal control circuit section 4 is switched to an analog type or a digital type. Depending on the case, it is also possible to use a switching method. Internal control circuit section 4
A data bus 9 and a control path 1 are connected between the
We are contacted via 6.

In response to the control signal from the control path 16, the input signal Sll~
The digital signals corresponding to 813 are sequentially sent to the arithmetic unit via the data bus 9.

The output signal output from the arithmetic unit is transmitted via the data bus 9, and taken into the internal control circuit unit 4 by a control signal transmitted via the control path 16, where data organization processing is performed. Furthermore, from here, the signals are distributed and output for each output signal system.

Output signals 821 and 822 output from the output circuit section 8
The switching position of each of the changeover switches &+3, 67, and 68 included in the changeover circuit section 6 is determined depending on whether the input signal is a digital signal or an analog signal. That is, when the output signals 821 , 822 , 823 are digital signals, the output signals from the internal control circuit 84 are directly routed to the respective insulation circuits 36 , 37 , 38 of the insulation circuit section 3 without passing through the D-A converter. are outputted to the output circuit section 8 via the output signals 821 and 822.

When 823 is an analog signal, the internal control circuit section 4
The digital output signal from is converted into an analog signal via the DA converters 76 , 77 , 78 of the DA converter 7 , and then output to the output circuit section 8 via the isolation circuits 36 , 37 , 38 . As shown in FIG.
67 and 68 are direct side without D-A converter or D-A
Pre-switched to the side with the transducer. Output signal S21
, 822, and S23 may all be digital or analog, but they do not have to be unified to either one, and may be a mixture of both. The selection is made using individual changeover switches 66, 67, 68.
carried out by The output signals 821 to S23 are used, for example, to drive meters connected to the outside by analog output, and to drive auxiliary relays connected to the outside by digital output.

In the embodiment shown in FIGS. 1 to 4, each signal circuit has an A
- to be able to insert a D converter or a D-A converter or to bypass it, in other words, to accommodate whether each input/output signal is analog or digital; All signal circuits are configured to be switchable. However, depending on the field of application, this type of input/output device has a ratio of analog to digital input/output points of approximately 1:4 (=additional percentage=8).
0%), which is often fixed based on experience.For such cases, as shown in Figure 5,
On the input side, assuming that 50% of the total input/output points are digital signals.

The switching circuit section 6 and the A-D converter section 5 are connected to each other.

The signal circuit from the insulation circuit section 3 to the internal control circuit section 4 via the bypass line 10 consisting of signal lines for each signal system is fixedly wired in advance, and similarly on the output side,
A bypass line 11 that bypasses the A-D conversion section 7 and the switching circuit section 6 and directly connects the internal control circuit section 4 to the insulation circuit section 3 can be used as a fixed wiring. In this case, the other parts are the same as those in FIGS. 1 to 4, and the entire device shown in FIG. 5 can be said to be of a semi-fixed type. By providing the fixed wiring portion using the binocular lines in this way, the total cost of the device can be reduced.

In the above embodiment, an A-D converter or a D-A converter is provided for each valley selector switch.
In order to transmit the digital signal obtained by D conversion to the data bus 9, a predetermined number of pits are required for every six converters. As a means to reduce the number of pits, a multiplexer 15 is arranged between the switching circuit section 6 and the A-D converter section 5, and the A-D converter section 5 is connected to a single commonly used A-D converter section. The input signal data may be transmitted to the data bus 9 by operating the multiplexer 15 in a time-sharing manner in response to commands from an external arithmetic unit or an external control device. By doing so, the cost of the A-D converter 5 can be reduced, and the cost of the entire device can be reduced. A similar idea can be applied to the output signal side. That is, in this case, the demultiplexer 17 may be placed between the DA converter 7 and the switching circuit section 6.

〔Effect of the invention〕

According to the present invention described above, by providing the switching circuit section, the AD conversion section, and the DA conversion section.

It can handle either analog or digital signals, making it easy to interface with processes. Furthermore, when designing a one-Russian controller, for example, the input/output section can be treated as a detachable or independent component, and this can be mass-produced. Therefore, it is possible to reduce the cost of the input/output device itself or the controller incorporating it.

[Brief explanation of drawings]

1 is a perspective view showing a schematic configuration of an input/output device according to a first embodiment of the present invention, FIG. 2 is a block diagram functionally expressing the device shown in FIG. 1, and FIG. FIG. 4 is a block diagram showing the specific configuration of the input signal circuit portion of the device; FIG. 4 is a block diagram showing the specific configuration of the output signal circuit portion of the device of FIG. 1;
FIG. 5 is a block diagram showing an input/output device according to a second embodiment of the invention, and FIG. 6 is a block diagram showing an input/output device according to a third embodiment of the invention. 1... Board, 2... Input circuit section, 3... Insulated circuit section. 4... Internal control circuit section, 5... A-D conversion section, 6.
...Switching circuit section, 7...D-A conversion section, 8...Output circuit section. Applicant's agent Kiyoshi Inomata 1 Figure 2 Figure 53 Figure 54 Figure

Claims (1)

[Claims] 1. At least one A-D converter and at least one D-A converter provided for a plurality of input/output signal lines formed on the same substrate; A switching circuit section that switches for each input/output signal line whether to transmit the incoming signal straight or through the A-D converter or the D-A converter, depending on whether the output signal is a digital signal or an analog signal. An input/output device for a controller, comprising: and on the substrate. 2. The input/output device for a controller according to claim 1, wherein an A-D converter or a DA converter is provided for each input/output signal line. 3. An A-D converter or a D-A converter is provided in common for multiple input/output signal lines, and the common A-D converter is provided in common for multiple input/output signal lines.
2. The input/output device for a controller according to claim 1, wherein a converter or a DA converter is used in a time-sharing manner for each input/output signal.