JPH0418606A - Sequence controller - Google Patents

Abstract

PURPOSE:To confirm all the operation states and to maintain slave station units by providing a storing means forming a condition data memory area to store the operation states of all the slave station units and a display means to display these operation states. CONSTITUTION:This device is equipped with a host communication station unit 1 so as to connect plural slave station units 4 through a communication cable 5 connected to this unit 1. On the other hand, this device is equipped with a RAM 9 forming the condition data memory area so that the operation states of all the above-mentioned slave station units 4 can be stored in this condition data memory area. Therefore, when the operation states stored in this condition data memory area are displayed at a display part 10, all the operation states can be confirmed. Then, the slave station units 4 can be easily maintained. On the other hand, since this device can confirm all the objective slave station units 4 in advance even when the plural slave station units are operated in abnormal states, the abnormality can be grasped as a whole.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a sequence control device equipped with a communication master station unit to which a plurality of input and output crab units are connected via communication cables.

[Conventional technology]

Generally, a sequence control device has a main body unit I- having a memory in which control procedures and the like are stored, and an input/output unit connected to actuators, sensors, etc. disposed in the device. The above-mentioned sequence control device monitors and controls sensors and actuators installed in the device, and operates the device according to a preset procedure.

Further, the sequence control device may be provided with a communication master station unit to which input/output crab units can be connected to the main body of the sequence control device via a communication cable. This communication master station unit is designed to be expanded by distributing multiple input/output units as slave station units, and is designed to cope with the increase and decentralization of monitoring targets and control targets due to larger devices, etc. There is.

The communication master station unit described in item 1 includes a CPU that monitors the communication status such as whether there is an abnormality in the slave unit, a ROM that stores a system program, a RAM that stores communication data, etc.
It also has a display unit that displays the station number and error details of the slave unit (see Figure 2).
The slave units with the lowest station numbers are searched in order, and when an abnormal slave unit is detected, the station number and error details are displayed on the display section of the programmer via the programmer. As a result, the conventional sequence control device
-] It is now possible to check whether or not there is an abnormality in the slave station unit using the communication master station unit (2), making maintenance and assembly easier.

(Problems to be Solved by the Invention) However, in the conventional sequence control device described above, when an abnormality occurs in a plurality of slave station units, only the smallest station number displayed on the programmer can be confirmed by the communication master station unit. Therefore, in the communication master station unit described above, it is difficult to use the programmer's display as data for maintenance when an abnormality occurs because it is not possible to grasp the abnormality as a whole. When attaching a set of sequence control devices, it is necessary to repair the slave station unit with the station number indicated by the programmer, and then fix the slave station unit with the station number displayed next. , the rise of the system will be delayed due to decreased workability.

Therefore, an object of the present invention is to provide a sequence control device that can comprehensively grasp the abnormality even when an abnormality occurs in a plurality of slave units.

[Means to solve the problem]

In order to solve the above-mentioned problems, a sequence control device according to the present invention includes a communication master unit to which slave units such as a plurality of input/output units are connected via communication cables, and includes a communication master unit to which slave units such as a plurality of input/output units are connected via communication cables. In a sequence control device capable of checking unit 1~, a RAM of a communication master station unit which is a storage means in which a situation data storage area for storing the operating states of all slave units is formed, and a RAM capable of displaying the above operating states. It is characterized by comprising a display section which is a display means.

[For production]

According to the configuration described in -1-, the sequence control device includes a communication master unit, and can connect a plurality of slave units via a communication cable connected to the communication master unit. There is. The sequence control device also includes a storage means in which a status data storage area is formed, and the status data storage area stores the operating status of all the slave stations mentioned in 1. It has become. Therefore, when the operating statuses stored in this status data storage area are displayed on the display means, all operating statuses can be checked, making it easier to maintain the slave unit.

In addition, even if multiple slave units are in an abnormal state, the sequence control device can check all target slave units in advance, making it possible to understand the entirety of the error. This will shorten the time it takes to start up a system due to improved work efficiency.

〔Example〕

An embodiment of the present invention will be described below based on FIGS. 1 and 2.

As shown in FIG. 1, the sequence control device according to this embodiment has a P
C (Programmable Control
r) It has a main body unit 2, and a programmer 2a, which is used for checking data contents etc. and is a display means such as manual operation keys, 7th segment, ED, etc., can be attached and detached to this PC main body unit 2. It is set in. Also,
The PC main unit 2 includes an input/output unit 3 that is connected to sensors, actuators, etc. installed in the device and transmits and receives control signals, and a communication master station unit 1 that uses a time slot method to exchange data at high speed. It is connected. Then, the PC main unit 2 monitors sensors, etc. by sending and receiving control signals etc. between the input/output crab unit 3... and the communication master station unit 1, and operates the device according to a preset control procedure. It looks like this.

The communication master unit 1 connected to the PC main unit l-2 is connected to one end of the communication cable 5.
The other end of the communication cable 5 is connected to a plurality of slave units 4, which are input/output units connected to sensors, actuators, etc., similar to the input/output units 3, etc. described above. In addition, slave station unit 4 described in -
may be an incoming unit and an outgoing unit with dedicated inputs and outputs.

As shown in FIG. 2, the communication master station unit 1 described above has a communication circuit 6 to which the communication cable 5 described above is connected, and this communication circuit 6 has a CPU (Central P
processing unit) 7.

The communication circuit 6 converts the signal output from the CPU 7 into a signal suitable for communication, while the slave unit 4...
・The signal transmitted from the CPU 7 is converted into a signal suitable for reception by the CPU 7.

A CPU monitoring circuit 12 is connected to the CPU 7 described above. This CPU monitoring circuit 12 includes, for example, a voltage monitoring circuit, a watchdog timer, etc., and is designed to stabilize the voltage and reset the CPU 7 that has gone out of control. The CPU 7 also includes a ROMB in which system programs are stored, a RAM 9 which is a storage means for temporarily storing communication data, etc., and a display unit that displays the station number and error details of the slave unit 4 when an abnormality occurs. 10 and an interface circuit 11 that allows data to be transmitted and received between the PC main body unit 2 and the PC main body unit 2.

A situation data storage area is formed in the RAM 9 to store the data shown in Table 1, and this situation data storage area stores the station number data of the slave station units 4, . . .・Input/output data showing the mode of no response,
Abnormality flag data indicating three types of abnormalities, such as errors and collisions, and status data indicating the presence or absence of an abnormality in the slave unit 4 are stored.

(Left below) Table 1: The data stored in the above status data storage area is transferred to the PC via the interface circuit 11 by handshake.
This handshake uses the 2 bytes at addresses 1570 and 1571 of the flag area of the PC unit 2, which are formed in the memory of the PC unit 2. It looks like this.

The data stored at address 1570 above is such that D7 and D6, which are two pins from the upper bit, are used as handshake flags, and
In the data stored at address 71, the two bits from the most significant bit, D7 and D4, are used as an error count flag and an error station number flag.

Furthermore, the station number where the error occurred is stored in addresses 1571 to 1571. The data stored at address 1571 is displayed on the programmer 2a, for example, as the total number and station numbers of slave units 4 in an abnormal state.

In the above configuration, the procedure for checking abnormal slave unit 4 will be described below.

The communication master station unit 1 monitors the operating status of the slave station units 4..., and data indicating this operating status is transmitted to the RA.
It is stored in the situation data storage area formed in M9. When reading data stored in the status data storage area, data for transmission is first written from the PC main body unit 2 to, for example, address 1570 in the PC main body flag area.

For example, if you want to check the total number of slave units 1-4... that are in an abnormal state, 00"' in octal is set to address 1570 above, and the status data stored in the status data storage area is The total number of data showing abnormalities is 1571.
It will be output to the address. At this time, if all slave stations Konin l-4... are normal, "'oo" is stored in octal number at address 1571, as shown in Table 2, and this "00"' is displayed on the programmer 2a.

Table 2 On the other hand, as shown in Table 1, three slave units 4 and 4
... is in an abnormal state, as shown in Table 3, ``83'' is stored in octal at address 1571.
This "83" will be displayed. This makes it possible to check whether or not there is an abnormality in the child station units 4 and the total number of them.

Table 3 Next, when checking the station number of the slave unit 4... that is in an abnormal state, as shown in Table 4,
"40" is set in octal at address 570. As a result, the smallest station number among the station number data stored in the status data storage area, for example 'C2'', is set to 157.
It will be stored at address 1, and this ``C2'' will be displayed.

After this, the first handshake between the PC main unit 2 and the communication master station unit 1 is completed by setting "80'" in octal to address 1570, and then '40' is set at address 1570. By setting , the station number of the slave station unit 4 . . . in the next abnormal state is displayed. With this in mind, by repeating the operation described in 1 above, it becomes possible to check all the station numbers of the abnormal slave unit 4...

Table 4 As described above, the sequence control device according to the present embodiment can confirm the presence or absence and total number of slave station units 4... that are in an abnormal state, and can also perform certain operations on the target station number. By repeating it, you can confirm it continuously. Therefore, since the sequence control device can grasp the entire abnormality at once, it becomes effective as data for maintenance when an abnormality occurs, and system start-up time is shortened due to improved workability. will be done.

In this embodiment, the total number and station numbers of the slave units 4 in an abnormal state are displayed, but the display is not limited to this, and for example, the number of slave units 4 in a normal state is displayed. ..., the station number, etc. may be displayed.

[Effects of the Invention] As described above, the sequence control device according to the present invention includes a storage means in which a situation data storage area for storing the operating states of all slave units is formed, and a display capable of displaying the operating states. The configuration includes means.

As a result, the operating status stored in the status data storage area can be displayed on the display means, making it possible to check all operating statuses, facilitating maintenance of slave units, and Even if the slave station unit I is in an abnormal state, it is possible to understand the overall abnormality, which improves work efficiency when starting up the system, making it possible to shorten the start-up time. It has the effect of becoming.

[Brief explanation of the drawing]

Figures 1 and 2 show an embodiment of the present invention. FIG. 1 is a schematic configuration diagram of a sequence control device. FIG. 2 is a block diagram of the communication master station unit. 1 is a communication master station unit, 2 is a PC main unit, 2a is a programmer (display means), 3 is an input/output crab unit, 4 is a slave station unit, 5 is a communication cable, 6 is a communication circuit, 7 is a C
PU, 9 is RAM (storage means).

Claims (1)

[Claims] 1. In a sequence control device that includes a communication master unit to which a plurality of slave units are connected via a communication cable and is capable of checking slave units in an abnormal state, all the slave stations A sequence control device comprising: storage means in which a status data storage area for storing the operating state of a unit is formed; and display means capable of displaying the operating state.