JPH03204059A - Programmable controller - Google Patents

Abstract

PURPOSE:To prevent erroneous data from being inputted and to attain the improvement of safety and the reduction of processing time by checking whether or not an appropriate peripheral unit is loaded with hardware before performing a data input/output operation. CONSTITUTION:At a controller main body 11, the code of a rack slot stored in a memory 12 for unit code and a machine specification identification code corresponding to the rack slot are read out, and they are sent to the slot of a corresponding rack as a unit code (a). The code (a) is written on the storage part of a discrimination circuit 16 in an input/output unit 13. At this time, a rack slot code (b) stored in a memory 14 for rack slot and a code (c) stored in a memory 15 for machine specification identification are read out at the circuit 16, and the collation of the codes (b), (c) with the code (a) is performed, and a coincidence signal (d) is sent from the discrimination circuit 16 to the main body 11 when coincidence is obtained. The main body 11 reads the signal (d), and confirms the normal/defective condition of loading of the unit 13 based on the signal (d).

Description

[Detailed description of the invention] Industrial applications The present invention relates to programmable control devices.

BACKGROUND ART FIG. 3 is a block diagram showing a schematic configuration of a conventional control device.

The control device main body 1 has a code that identifies the device, that is, the rack, in which the input/output crab unit 4, which is a peripheral device that exchanges signals with the control device, is installed, and codes of the plurality of installation positions, that is, slots set in the rack. A function is provided to send the rack/slot notification signal p containing the rack/slot notification signal p to the slot of the corresponding rack. The control device main body 1 also includes an input/output unit 1-4 and identification data, that is, an input/output cover pattern for identifying whether the input/output crab unit 4 is an input device or an output device, and the input/output crab unit 4 and controls. tx
A model identification memory 2 is provided in which the number of bytes of data to be input/output to/from the device main body 1 is written in association with each rack/slot.

On the other hand, the input/output crab unit 4 includes a rack/slot memory 5 in which the code of the rack and slot in which the input/output crab unit 4 is to be installed is written, and a code and a control device read from the rack/slot memory 5. Main body 1
A determination circuit 6 is provided which determines whether or not the code of the rack/slot selection signal p sent to the rack slot matches the code of the rack/slot selection signal p sent from the rack/slot selection signal p. Furthermore, this input/output unit 4 is reset by a coincidence signal output from the discrimination circuit 6, and is incremented every time one byte of data is input/output between the control device main body 1 and the input/output unit 4. A counter 7 that counts up to the number of bytes of input/output data specified in the input/output crab unit 4, and a memory 8 for input/output patterns in which input/output cover patterns of the input/output crab unit 4 are written are provided. The input/output cover pattern 8 is controlled as an input/output determination signal q for determining whether the input/output unit 4 is an input device or an output device, and is sent to the TII\i device main unit. Further, the count value of the counter 7 that has reached the number of bytes specified in the input/output unit j.4 is sent to the control device main body l as an end signal r indicating the end point of the data input/output operation.

Furthermore, the control device main body l includes the input/output unit I-4.
+7) A memory 3 is provided to temporarily store an input/output discrimination signal q and an end signal r sent from the input/output cover turn memory 8.

In the above control device 11, when the rack/slot selection No. 13 p for selecting the input/output crab unit 4 to be subjected to input/output operation from the control device main body l is sent to the slot of the corresponding rack, it is installed in that slot. The determination circuit 6 of the input/output crab unit 4 that has been input/output selects the rack/slot selection signal p from each code of the rack/slot and the rack/slot selection signal p.
A comparison is made with the code read from the slot memory 5. When these codes match, a match signal S is outputted from the discrimination circuit 6, and the color/tough is reset by the match signal S. As a result, the data written in the input/output pattern memory 8, that is, the input/output pattern is read out by the counter 7, and the input/output pattern is read out by the counter 7.
The output pattern is applied to the memory 3 of the control device 1 as an input/output determination signal 9.

Thereafter, data input/output operations are performed between the control device main body 1 and the input/output crab unit 4 based on the read signal R and write signal W output from the counter 7. The counter 7 is incremented every time one byte of data is input/output, and when the count value reaches a specified number of bytes, the count value is output as the end signal r and written to the memory 3 of the control device main body 1. . As a result, the control device main body 1 knows that the data input/output operation should be ended.

Through the above operations, the input/output discrimination signal 9 written in the memory 3, that is, the input/output cover turn of the input/output crab unit 4, and the end signal r, that is, the number of bytes specified for the input/output crab unit 4, is used for model identification of the control device 2. The input/output pattern and number of bytes corresponding to the rack/slot code at this time, which are written in advance in the memory 2, are compared with the input/output pattern and number of bytes, and based on the results, it is determined whether the correct input/output uni-soto 4 is installed in the rack/slot. It is determined whether or not.

Problems to be Solved by the InventionHowever, in the case of the conventional control device described above, the composition is such that it is determined whether or not the correct input/output crab unit 4 is installed only after the data input/output operation is actually performed. Not only is there a possibility that data input/output operations are performed with the wrong input/output crab unit 4, but also the input/output pattern and the number of bytes sent from the input/output crab unit 4, which have been previously stored in the control device main body 1 at t3, may be incorrect. Since the input/output patterns and number of bytes are checked by software, the problem is that the processing takes time.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a programmable control device that prevents erroneous data from being input/output and can shorten processing time.

Effect According to the present invention, before performing an actual data input/output operation,
Since the hardware is configured to check whether the appropriate peripheral devices are installed, it prevents incorrect data from being input/output, improving safety and reducing overall processing time. can.

Embodiment FIG. 1 is a block diagram showing a schematic configuration of a control device that is an embodiment of the present invention. The control device main body 11 includes
A code that identifies the rack in which the input/output crab unit 13, which is a peripheral device that sends and receives signals, is installed and the slot that is the installation position set in the rack;
The model identification code for identifying the input/output crab unit 13 associated with that rack and slot is one-to-one.
A unit code memory 12 is provided in which the unit code a is stored in the form of a comparison table in correspondence with the unit code a, and the unit code a in this memory 12 is sent to the slot of the corresponding rack. In this case, if the data amount of the unit code a is, for example, 1 byte, 5 bits of it are allocated to the rack/slot code, and the remaining 3 bits are allocated to the model identification code. As specific contents of the model identification code, the input/output pattern and number of bytes shown in the conventional example are used.

On the other hand, in the input/output crab knit 13, the input/output crab knit 1
A rack/slot memory 14 stores the codes of racks and slots to be installed, and a model identification code assigned to each input/output unit 13 to identify the model of the input/output unit 13 is stored. Do the codes b and c read from the rack/slot memory 14 and model identification memory 15 match the code a sent from the control device main body 1 to the rack/slot? A determination circuit 16 is provided which determines whether or not the two match, and sends a match signal d to the control device main body 11 when they match.

FIG. 2 is a flowchart showing the operation of checking the attachment of the input/output crab knit 13 in the control device.

Next, the operation of checking the attachment of the input/output crab knit 13 by the control device will be explained. First, in step S1,
In the control device main body 11, the rack/slot code and the corresponding model identification code stored in the unit code memory 12 are read out, and this is sent to the corresponding rack slot as the unit code a.

The unit code is written in a storage section (not shown) of the discrimination circuit 16 of the input/output crab unit 13 installed in the rack/slot in step S2.

At this time, the discrimination circuit 16 uses the rack/slot code b stored in the rack/slot memory and the model identification code C stored in the model identification memory 15.
An operation is performed to compare these codes bc with the unit code a from the control device main body 11, and if these codes match, a match signal d is sent from the determination circuit 16 to the control device main body 11. is sent out.

In the next step S3, the coincidence signal d sent from the determination circuit 16 is read in the control device main body 11.

At this time, it is determined in step S4 whether or not there is a coincidence signal (l).
1, if there is a coincidence signal d, it can be confirmed that the correct input/output crab knit 13 is installed, and if there is no coincidence signal d, it can be confirmed that the wrong input/output crab knit 13 is installed.

Effects of the Invention As described above, according to the present invention, before an actual data input/output operation is performed, the hardware is configured to check whether or not a proper peripheral device is installed. There is no need to input or output data, improving safety and reducing overall processing time.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing a schematic configuration of a control device according to an embodiment of the present invention, FIG. 2 is a flow diagram showing a check operation of the control device, and FIG. 3 is a schematic diagram of a conventional control device. FIG. 2 is a block diagram showing a configuration. DESCRIPTION OF SYMBOLS 11... Control device main body, 12... Memory for unit code, 13... Input/output crab unit, 14... Memory for rack/slot, 15... Memory for model identification, 1
6...Discrimination circuit

Claims (1)

[Claims] By mounting a peripheral device corresponding to a predetermined mounting position of a device for mounting a peripheral device in which a plurality of peripheral device mounting positions are provided, a connection between the peripheral device and the main body of the control device can be established. In a programmable control device that enables proper transmission and reception of signals, the main body of the control device includes a mounting position code that identifies the mounting position for each mounting position of peripheral device mounting equipment, and a mounting position code that identifies the mounting position. A selection signal output circuit is provided to send out a peripheral device selection signal including a model identification code assigned to a corresponding peripheral device, and the peripheral device is provided with a selection signal output circuit that indicates a mounting position of a peripheral device mounting device corresponding to the peripheral device. A mounting position code memory that stores the mounting position code, a model identification code memory that stores the model identification code indicating the peripheral device, and the mounting position code of the mounting position code memory and the model identification code of the model identification code memory. and a code comparison circuit that reads the code and compares it with the code of the selection signal sent from the control device main body, and sends a match signal to the control device main body when the two codes match, and the code comparison circuit reads the code of the selection signal sent from the control device main body. A programmable control device characterized in that a coincidence signal is used to inform the main body of the control device that a proper peripheral device is attached to a mounting position of a peripheral device.