JPS58182740A - Key scanning device - Google Patents

Abstract

PURPOSE:To shorten the processing time of a key scanning device, by providing a muCOP exclusively used for key scanning with each key switch group to detect a change of state, transmitting the detected change of state to a control computer and providing a data converting function for each plant. CONSTITUTION:Matrix-shaped key switch groups 5A and 6A are joined to exclusive muCOP5B and 6B to form key scanning parts 5 and 6. The muCOP5B and 6B scan successively the groups 5A and 6A to detect the presence or absence of a change of state. The change of state if detected is fed to a CPU8A of a muCOP8 through cables 7A and 7B. The muCOP8 performs the necessary conversion of data for the change of state by means of a memory 8B which stores different data for each plant and for the change of state of the received key switch. Then the state of change is sent to a host computer 4. In such a way, the number of cables is decreased. This reduces the load of the computer 4.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a key scanning device using a microcomputer, and more particularly to a device for coupling a key switch group and a microcomputer.

Generally, in a plant monitoring and control system, the operation status of push-button switches installed in the monitoring and control room and the status of equipment to be monitored and controlled are input into the main body of the monitoring and control device as status monitoring signals, and each glaze is controlled based on these monitoring signals. get the output. The status monitoring items for each part of the system are grouped into the departments that make up the entire system, but there are not many items, and the status monitoring items are imported using a microcomputer that determines whether or not changes are made for each item. A key scan method is used that performs periodic sequential checks.

FIG. 1 shows a conventional key scanning device. The key switch group 1, in which the source of the status monitoring signal is a push button switch or a relay contact, is arranged in a matrix and connected to the key controller 2 by cables 3A and 3B. Through the key controller 2 and cable 3Ai, the row trace selection details of key switch group 1 are sequentially driven, and through the cable 3B, the output states of the column outputs are used as parallel data to drive each switch of 114th order drive 9 and key switch #+1. Determine whether or not there is a state change. The key controller 2 issues an interrupt to the computer 41111 when there is a change in the state of the key switch.

The data received by the 0PU4A of the computer 4 due to this interrupt is changed to indicate that the switch in the row and column of the key switch group 1 has the status 'NJ4 changed.

0PU4A performs necessary calculations based on state change data,
For example, a memo 1J that stores shared data for each plant.
4E-i is used to convert the data, and a control output for a display, a relay, etc. is sent out through the output device 40. Note that a plurality of key switch group 1, controller 2, and cables 3A and 3B are installed depending on the scale of the plant, and computer 4
is combined with

As the opportunities for monitoring and controlling these conventional devices increase,
This increases the number of cables 3A and 3B, increases the burden on the computer 4, increases construction costs, increases installation space, and lowers cost performance.

The present invention detects changes in the state of the key switch using a microcomputer dedicated to key scanning in the key switch group, and connects the control computer with a microcomputer dedicated to suppressing the key switch using a data transmission cable. By providing a microcomputer for the transmission controller and providing the microcomputer for the transmission controller with a data conversion function for each plant according to changes in the status of the key switch, the conventional problem of failure can be solved and the effects described later can be achieved. The purpose of the present invention is to provide a key scanning device that can perform the following tasks.

FIG. 2 is a block diagram showing one embodiment of the present invention. The matrix-shaped key switch groups 5A, 5A are arranged in key scanning sections 5, 6 connected to dedicated microcomputers 5B, 6B, respectively.

Microcomputer 5Bj6Bi, J: Like the conventional key controller 2, it has a function of sequentially scanning each of the key switches Bt'5Aj6A to detect whether or not there is a change in state. And microcomputer 5B.

When 6B detects a state change in the key switch, it transmits it to optrB of the common transmission controller microcomputer 8 through transmission cables 7A and 7B'. The microcomputer 8 performs the necessary data conversion in response to the received key switch state change using a memo IJ8B' that stores data that differs from plant to plant, and sends this converted data to the post computer 4 via an interrupt. input.

According to such a key scanning device, the key switch group 5A, 5A has a microcomputer 5B, 6B\r dedicated for key scanning, so the cable 3A for key scanning seen in the conventional device is required.

In this embodiment, instead of 3B, 2 to 4 pairs of transmission cables 7mm i7" are used, reducing the number of transmission cables and construction costs. In addition, the computer 4ill is connected to the key switch section. Since it has a transmission controller microcomputer 8 that performs data conversion and data conversion, the load on the computer 4 can be reduced.Furthermore, key switch status changes can be done by data transmission between the computers 5B, 6B and 8, allowing for distributed monitoring and control. It is possible to centralize management and reduce the processing time of the system.In addition, in the present invention, the key operations from the operator's perspective are the same as in the past, making it easy to apply to existing systems. achieved.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a conventional key scanning device, and FIG. 2 is a block diagram showing an embodiment of the present invention. 4... Computer, 5, 6... Key switch section,
5A, (iA...key switch group, 5B, 6B...
Giescan dedicated microcomputer, 7A, 7B.
...Transmission cable, 8...Microcomputer for transmission controller.

Claims (1)

[Claims] In a key scanning device that reads the states of a group of key switches by sequential scanning, this microcomputer is connected to a microcomputer dedicated to key scanning, which sequentially scans the keyswitches 8+ to detect all changes in their states, and this microcomputer is connected by a transmission cable. The present invention is characterized by a transmission controller microcomputer that receives all key switch data and performs necessary data conversion, and an interrupt from this microcomputer that inputs data corresponding to the key switch whose state change is detected to the control computer. key scanning device.