JPS5929882B2 - sequence controller - Google Patents

Description

[Detailed description of the invention] The present invention relates to a stepwise sequence controller.

There are two types of sequence controllers: progressive type and scanning type.
The step-by-step type controls in such a way that when the operation corresponding to a certain step of the control program is completed, the program is caused to advance one step by the completion detection signal and the operation of the next step is started. be. In the scanning type, data indicating the state of the controlled system is input to the input device of the control device, and the control device constantly scans the input device to detect the state of the controlled system and determines the state according to the state. It is now possible to carry out controlled controls. The scanning type allows virtually continuous control, but it is difficult to create a control program and the control device is complicated and expensive. Step-by-step control devices have the disadvantage that the controlled system operates in stages and can sometimes only be controlled in a clumsy manner, but the program is easy to create, anyone can create one, and the control device is relatively inexpensive. Moreover, since there are many controlled objects for which stepwise control is actually sufficient, the sequence controller is very economical for such objects. The present invention is directed to the above-mentioned step-type sequence controller. Conventionally, this type of sequence controller used a pin board and pins to create a program and input it to a control device (sequence controller). The purpose of this design was to enable a program to be input to a control device by operating several keys arranged on a keyboard.

With a pinboard type sequence controller, the program is input to the sequence controller by inserting a pin into a predetermined position of a pin hole in a predetermined stage of the pinboard for each step of the Pukagram, so the entire program created is based on the pin arrangement. Although it has the advantage of being displayed by the pin board, it is not reliable enough due to poor pin contact, requires a large number of pins, and managing them is troublesome. There are disadvantages such as an area force of .

According to the present invention, a program can be input to a sequence controller by operating keys on a keyboard, so problems such as pin management, poor pin contact, and the need for a sequence controller with a large pin board when the number of steps in a program increases. This eliminates the need for a pinboard system in terms of management, reliability, and cost (especially when the number of program steps is large). However, with the method of inputting programs by key operations, there is a possibility of pressing the keys in the wrong order or pressing the wrong key altogether, and such erroneous operations can disrupt the format of the commands and cause completely meaningless commands to be input. Therefore, it is necessary to avoid making mistakes in key operations. On the other hand, the result of the operator's operation is displayed on the display screen of the device, and the operator should be able to read the display and judge whether his or her operation is correct or not, but what appears on the display screen are codes that encode commands and data. Therefore, even if an operator is a skilled operator, it is difficult to immediately notice his/her mistake just by looking at the display, and there is a possibility that he/she may continue writing the program without noticing the mistake. Therefore, the present invention is a step-by-step sequence controller in which a program is input by key operation, and in order to solve the above-mentioned problems, when an error occurs in the operation, the device detects the erroneous operation. The present invention provides a sequence controller that issues a warning and makes an operator aware of an erroneous operation.

The present invention will be explained below with reference to Examples. FIG. 1 is a front view of an operation panel of a sequence controller according to an embodiment of the present invention. The set of keys 1 in the lower right corner of the panel are commands,
The keys on which numbers are written as input keys for data etc. are used for both inputting commands and inputting data numbers, and the keys on which Roman letters are written are keys for operation. The two upper and lower display sections 2 and 3 at the bottom left are rows of output terminal indicator lamps, numbered 32 from 1 to 32.The lamp at the position indicating the output terminal specified in a certain program step will light up. ing. The two rows of display sections 4 and 45 on the upper right are a row of input terminal indicator lamps numbered 1 to 32, and when an input is applied to the input terminal specified in a certain program step, the corresponding lamp lights up. . The number display section 5 below the display section 3 is divided into four frames 51, 52, 53, and 54. The leftmost frame 51 displays the step number in two frames, and the right frame 52 displays the step number. represents the type of instruction as a one-digit number, and the number 4 in the example shown in the figure means, for example, an AND instruction.
A bilingual table of the command word and its code number is written in the frame 6 below the number section 5. 3rd from the left in number display section 5,
The rightmost frames 53 and 54 are each two-digit numbers, each representing a numerical value of data. Next, we will outline the operation method for the above panel.

Program writing. First, turn the power switch PS to the on side, then turn the program console switch CS to the on side, and then turn the switch S2 to set the step to ``00''.
Flip it once to the reset side. Also, it is assumed that all memory for storing programs has been cleared. Then, input each step of the program in sequence. Each step of the program starts with INS in the key group at the beginning of writing.
Press the key and then press the command key. Since the command for each step is always one word, pressing the numeric key after the INS key automatically becomes a command input operation, and subsequent key operations automatically become data input. Therefore, the same key can function either for command input or for data entry, depending on the order in which it is pressed during a write operation. First, write the instruction for the 0th step. Press the INS key, then press the number 2 key. The number 2 key is a return command, that is, a command to return to the starting point.
From the left of the number display section, the first frame 51 is 00, and the second frame 52 is 62''. This is all you need to do at the 0th step, and then press the R/W key. , a return command is written in the memory, and by pressing the R/W key, the step is automatically advanced, and the display in the first frame 51 of the number display section becomes 6011, and all other frames become 0. Here, enter the command for the first step.For example, if this step is to output output to output terminals 2 and 4 by ANDing the inputs of input terminals 1 and 3, first input the INS as expected. When you press the key and press 4, which indicates the AND command, the display in the frame 51 of the numeric display section becomes 4.Since the command is limited to one word, the next key you press will naturally be a data input operation. In this case, the command is to AND the inputs of input terminals 1 and 3, so press the number key "00" and then "1".The display in the frame 53 of the number display section becomes 01, and then the number key "O" is pressed. When you press , and then press ``4'', the display in the frame 54 of the numeric display becomes 04, and the numeric display shows the content of the first step of the program by 6 and ``01''.
04" will be displayed. Next, press the 0UT key to specify the output terminal, and the lamp with the number 1 on the display section 3 will blink. Next, press the 0FF key, and the lamp above the number 1 on the display section 3 will flash. The lamp disappears and the lamp above the number 2 flashes.Next, when you press the 0N key, the lamp above the number 2 lights up and the command content to output to the output terminal 2 is displayed.The output is Terminals 2 and 4 are connected, so press the 0FF key again.Then, by pressing the OFF key, the number 3 on the display section 3 will change.
The lamp above goes out, and then by pressing the 0N key, the fourth lamp lights up, indicating that the fourth output terminal has been designated. Now that the configuration of the first step command is complete, press the R/W key to write the first step command in the memory and advance the program step one step. 802'' will be displayed.The program contents will be input into the memory step by step by the operations described above.In this way, if the last step is to repeat the entire program 15 times, Then press the keys in the following order:
INS” “8” (Repeat instruction code number) “1”
．． "5" (means 15 times) "O""1" (means from step 1 of the program, that is, steps from step 1 to this step will be repeated 15 times.) "R/W"
Press as if saying. The formal end of the program is “EN
In the next step of the above repeated command with the command "D", "IN
Entering the entire program is completed by key operations in the order of ``S'', ``END'', and ``R/W''. Next, to run the above program, set the program console switch CS to 0.
Turn it to the FF side, turn the switch S1 to the 6-auto 0 side, and turn the start switch S3 down one degree.

The program will now start running. While the program is being executed, the indicator light 55 to the right of the number display section 5 is lit. Each frame of the numerical display section 5 numerically displays the number of the program step currently being executed, the contents of the program, etc. For example, while the first step is being executed, the number 01 appears in the first frame 51 of the numeric indicator 5, indicating that it is the first step, and when the command for this step is AND, the number 01 appears in the first frame 51 of the numeric indicator 5
2 indicates the number 04, and if the two input terminals that should satisfy the AND condition are No. 1 and No. 3, the third frame 5 of the number display section
The number 01 appears in 3, and the number 03 appears in the fourth frame 54. In this first step, the specified output terminal 2
, 4, and the lamps 2, 4 of the display section 2.
lights up. In the first step, when input signals are input to both input terminals 1 and 3, the program advances through the first step, and the display of the numeric display section changes to the content display of the second step, and the execution of the second step is started. That is, as the program progresses, when the command contents of a certain step, that is, the setting conditions are satisfied, the step is incremented and the next step is executed. FIG. 2 is a block diagram showing the internal structure of the above-mentioned apparatus.

The block marked "CPU" is the central control unit of this device, which is a microcomputer, and M is the memory for storing the program to be executed by this sequence control device, into which the program is stored by the program write operation described above. Assume that a certain step of a program is currently being executed and output specified by that step is being output.At this time, the CPU reads the instruction of the above step from memory M and stores it in the accumulator in the CPU. On the other hand, the human input terminals 1NI-1Nn are constantly scanned to sense their input states, and this input state and the input terminal number and conditions in the instruction of that step stored in the accumulator are used by the CPU's built-in arithmetic discrimination circuit. Compare with
If the two match, 1 is added to the number of addresses specified in memory M, the next step is read out, and the same operation as above is performed. That is, this device uses a step-by-step type of external load control, but internally performs a scanning-type sequence control. (Shikomi)
This scanning-type sequence control is constant as described above, regardless of the operations to be executed externally, and this internal control program is stored in the read-only memory (
It is stored in ROM). When writing a program to control an external load, the CPU reads an internal control program for program writing from the ROM, and according to the program, the above-mentioned panel keys 1, console switch CS, switch S2, etc. are connected. Repeatedly scans the input state of the internal input circuit. To be exact, the CPU is a ROM
External input circuit 1 according to the internal control program written in
Scans the open/close states of the console switch CS, switch S2, etc. connected to each input terminal INl to INn of N and the internal input terminal, and the key group 1, etc., and writes or executes the program depending on the input state of the internal input circuit. or other operations, and each operation is executed according to the input state of the internal input circuit. In this case, the input state of the internal input circuit is program writing, so as mentioned above, only key group 1 and the internal input circuit are scanned, and the commands set by the key group are sequentially written to memory M. Go. Furthermore, during program writing, execution, and other operations, the CPU displays the contents of the steps in the program being written, the contents of the steps in the program being executed, the contents of specified steps in the program, etc. on the numerical display section 5 and the display section. The operations displayed in 2, 3, etc. are executed according to an internal control program in the ROM. In short, C.P.
The U is operated by an internal control program written in the ROM that controls the CPU itself, and the internal control program that controls the CPU is switched depending on the input state of the internal input circuit to control the external control of the entire device. The operation switches to writing the external load control program, executing the program, etc.

Further, a random access memory RAM is used as a step counter that increments steps in the execution of an external control program. Since the general description of the normal program writing operation and the operation during program execution of the apparatus of the present invention has been completed above, the erroneous operation during program writing and the corresponding operation of the apparatus at that time will be explained below. An example of an erroneous operation in the program writing operation is, for example, when writing one program step by pressing the ``W'' key, the display on the display section 51 displays the next step number. Writing the next step command is IN.
Since it starts by pressing the S key, you should generally press the INS key after pressing the R/W key, or if you want to check the command of a step that has already been written, or if you want to change the program. If you want to skip a step and write to the next step, press the SETSTEP key. Therefore, it is wrong to press the number key immediately after pressing the key. Also, when you press the INS key, you are writing a command, so the command key is used.In this example, the command key is used in combination with the numeric keys, so you need to use keys other than the numeric keys, such as the SETSTEP key or the 0UT key (command key). It is a mistake to press ) to specify the output key in . When an erroneous operation as described above is performed, the device detects the erroneous operation and issues a visual warning such as flashing a display to draw the operator's attention.

Also, the result of the erroneous operation is not entered into the memory at all, and the write operation remains in the state it was in before the erroneous operation was performed. Therefore, the operator only has to look at the displays on the displays 2, 3, and 5 and perform the correct operation to continue with the content represented by the displays. For example, when you press the INS key and then press the 0UT key, the buzzer will sound, so you can immediately press the desired number key again.The incorrect operation is caused not only by the program write operation but also by the written program. This can also occur when checking the program by going back and displaying the steps.

In such a case, press the SETSTEP key mentioned above, but when you press this key, you should press a number key next to specify the step number, and then press the INS key or R
It is a mistake to press the /W key. Even in such a case, the device displays a warning display, does not accept the result of the erroneous operation, and the device remains in the state before the erroneous operation. FIG. 3 is a flowchart of the above-mentioned operation in the apparatus of the present invention, and a program for realizing this operation is preset in the ROM shown in FIG. 2.

The CPU repeatedly scans the open/close states of switches such as console switch CS, the state of key group 1, etc., and determines whether the console switch CS is on or off. If it is on, it means writing a program or checking a program, so next it is SET.
Asks if the STEP key was pressed, if NO, asks if the INS key was pressed, if NO, asks if the 0UT key was pressed, and if the SETSTEP key was pressed, then asks if a numeric key was pressed. If NO, it is an incorrect operation and the buzzer will sound, indicating that the SETSTEP key was not pressed and it is IN.
If the S key has been pressed, a question is asked as to whether a command key (in the embodiment, a numeric key) was pressed next, and if NO, it is an erroneous operation and the buzzer sounds.

Similarly, the 0UT key is pressed, then the 0N key or 0F
If the F key is not pressed, a warning is displayed because it is an erroneous operation. In the explanation of the flowchart above, the question "Whether a numeric key was pressed" was written that way for convenience; in reality, at this stage, the question is whether or not a key other than the numeric key was pressed, and is simply It does not operate to display a warning just because a number key is not pressed. Otherwise, since the CPU is scanning at high speed, there will be some blank time between pressing the INS key and pressing the next number key (command key).
During this blank time, a warning display is displayed, creating a very noisy situation. Therefore, SETSTEP the details of the flowchart.
The line after the question asking whether a key has been pressed is shown as a representative example in FIG. That is, if YES to the question of whether the SETSEP key was pressed, it asks whether a key other than the numeric key was pressed; if YES to this question, a warning is displayed; if NO, it asks if a numeric key was pressed; if NO, then it asks whether a numeric key was pressed. The operation of returning to the step of asking whether a key other than a numeric key has been pressed is repeated until a numeric key is pressed. Various methods of visual warning are possible.

For example, you can leave the display on the display as it was just before the erroneous operation and simply make it blink, or you can make the letter E appear on the display to indicate the erroneous operation (Figure 5a), or you can make dots or lines appear on the display. (Fig. 5B, c), or a separate warning indicator light may be provided and turned on or blinking. These displays can be implemented in various formats depending on a control program for displaying a warning in the event of an erroneous operation, which is stored in the ROM. The device of the present invention has the above-described configuration, and when an erroneous operation is performed, a visual warning is displayed, so the operator does not notice the erroneous operation immediately, unlike when the result of the erroneous operation is simply displayed. This allows operations such as writing and checking programs to be performed efficiently.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention; FIG. 1 is a front view of the device, FIG. 2 is a block diagram showing the internal configuration, FIG. 3 is a flowchart of the main part of the device's operation, and FIG. 4 is a flowchart of the above flowchart. FIG. 5, which is a partially detailed flowchart, is a front view of the display section showing three examples of malfunction warning display formats. 1...゜・Key of key group, 2, 3, 5...
Display unit, ℃PU...Central control unit, M...
...Memory to write the sequence control program.

Claims (1)

[Claims] 1 Input terminals, output terminals, command and data input keys, switches for switching between program writing and program execution, and memory for writing programs, and the input terminals, commands and data input keys, and switching operations for program writing and execution. The switch is scanned, and when the switch is set to the program write operation, the above command and the command set by the data input key are written to the memory, and when the switch is set to the program execution side, the command set by the data input key is written to the memory. When the program is running, the internal control program reads the contents of one step of the program from the memory, executes the read instruction, and when the execution is completed, reads and executes the contents of the next step in the memory. a central control unit with a ROM that is
The ROM determines whether or not the next operated key is appropriate for the format of one step of the program, and if it is incorrect, displays a visual warning on the display. A sequence controller characterized in that an internal control program is set to prevent the results of the inappropriate key operation from being written into the memory in which the program is written.