JPS622325B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a sequence display device that converts a sequence program stored in the memory of a sequence controller into a predetermined symbol pattern and displays it externally in a ladder diagram format. By simply programming simple display data during programming, you can change the symbol depending on the type of input/output element and display the purpose of the input/output element, creating a display that closely resembles the actual relay circuit diagram. The goal is to make it possible. In recent years, sequence programs stored in the memory of sequence controllers have been converted into ladder diagrams and displayed externally, making it easier to monitor sequence programs. However, in conventional sequence display devices, if the read sequence program is a test command, a pattern representing a contact point is displayed, and if the read sequence program is an output command, a pattern representing a relay is displayed. In the ladder diagram displayed by the sequence display device, it is not possible to determine at all whether the input element is an auxiliary relay contact, a pushbutton switch, a limit switch, etc. It is very difficult to read compared to general relay circuit drawings, which are written with unique symbols. In addition, in general relay circuit diagrams, the purpose of the circuit, the names of input/output elements, etc. are written, but conventional sequence display devices cannot display these additional data, and the displayed It made the circuit more difficult to understand. The present invention has been made in view of the conventional problems, and when display data is added to sequence program data, a pattern of symbols specified by the display data is displayed, The present invention is characterized in that it is possible to display a usage code specified in the display data. Embodiments of the present invention will be described below based on the drawings. In FIG. 1, 1 indicates a stored program type sequence controller, which includes a sequence memory 10 for storing sequence programs;
Arithmetic processing unit 11 that executes a sequence program
and an input circuit 12 to which input elements such as a push button switch PS10 and a limit switch LS1 are connected.
and an output circuit 13 to which output elements such as a relay CR10 and a solenoid SOL13 are connected. In the sequence controller of this embodiment, a sequence program is created from a relay circuit diagram, and command words as shown in Table 1 are used.

[Table] Command words include test commands (TNA, TFA, TNO,
TFO, TNE, TFE), output instructions (YON), and invalid instructions (NOP).For test instructions and output instructions, the upper 5 of the 16 bits that make up one word are used as shown in Figure 2a. An instruction code is programmed into the bits, and input/output address data for selecting input/output elements is programmed into the lower 11 bits. In addition, the invalid command NOP is used to program data for display,
As shown in Figure 2b, of the lower 11 bits of the operand section, the upper 4 bits are programmed with a code for changing the symbol pattern, and the lower 7 bits are programmed with a code for displaying usage data. . In this embodiment, there are five types of codes for symbol change as shown in Table 2, and a third code for displaying usage data.
There are 32 types available as shown in the table.
If these codes are programmed into the operand portion of an invalid instruction, patterns can be changed and usage data can be displayed in accordance with the programmed codes.

【table】

[Table] After the data of the sequence program programmed with such command words is written into the sequence memory 10 by a program writing device (not shown), when the operation of the sequence controller 1 is started, the operation is started. The processing unit 11 sequentially designates different memory addresses in the sequence memory 10, reads out the sequence program, and performs processing according to the instruction words of the read sequence program. That is, if the sequence program read from the sequence memory 10 is a test instruction,
The input/output address data of the lower 11 bits of the sequence program is sent to the input/output circuits 12 and 13 to select the input/output element, and then the selected input/output address data is sent to the arithmetic processing unit 11 via the signal line IOB. The on/off signal from the output element is read internally, a test is performed, and the test result is stored. Further, if the sequence program is an output command, an output element is selected based on input/output address data, and a command signal to turn on/off the selected output element is sent to the output circuit. On the other hand, if the read sequence program is an invalid instruction NOP, the next sequence program is read without performing any processing. Therefore, even if display data is programmed into the operand portion of the invalid instruction NOP, it does not affect sequence control. Next, the sequence display device 2 according to the present invention will be explained. This sequence display device 2 selects and reads a sequence program related to a specified output element, converts the read sequence program into a ladder diagram, and displays it on a CRT (cathode ray display tube). It has the function of displaying on/off status and the function of changing the symbol pattern or displaying the purpose depending on the display data. The program reading circuit 20 is a digital switch.
It searches for a sequence program related to the output element connected to the input/output address set in DS1, and while the sequence program read from the sequence memory 10 is a test instruction or an invalid instruction, the read sequence program and the on/off state of the input/output element selected during the test are sequentially written into the buffer memory 21, and when the output command is read, the operand part of the read output command is set to the input/output state set in the digital switch DS1. It is determined whether they match the address data, and if they match, the output command and the following invalid command are transferred to the buffer memory 2.
1, stop reading the sequence program, and if the two do not match, clear the memory contents of the buffer memory 21, and write the test command following the output command and the on/off signal of the input/output element to the buffer memory 21. Write again. Now, if the starting circuit for advancing the jig shown in FIG. 3 is to be monitored, the input/output address 130 of the relay CR10 is set to the digital switch DS1 and the operation of the sequence display device is started. As a result, among the sequence programs stored in the sequence memory 10, the sequence program related to the indicated relay CR10 is read, and this is stored in the buffer memory 21 together with the signal indicating the on/off of the input/output element. For example, if the program related to relay CR10 is stored in addresses 1000 to 1007 of sequence memory 10 as shown in FIG.
The sequence program up to address 1007 is written into the buffer memory 21 along with signals representing the on/off states of the input/output elements. FIG. 5 shows the storage state in the buffer memory 10, in which 1 and 0 indicating the on/off state of input/output elements are stored after the sequence program data. Also, relay CR10
An invalid instruction NOP in which display data is programmed is also programmed in the sequence program related to the above, and this invalid instruction NOP is also stored in the buffer memory 21. A circuit constituted by a refresh memory 22, a character generator 23, and a timing signal generation circuit 24 sends pattern data corresponding to the data written in the refresh memory 22 to a video signal generation circuit 25. , a pattern according to the data written in the refresh memory 22.
This is something that is displayed on a CRT screen, and if you want to display numbers or uppercase alphanumeric characters, you can write the numbers or alphanumeric characters you want to display in ASCII code (ASCII code).
If it is desired to display patterns of relay contacts, limit switches, etc., a special code as described later is written in the refresh memory 22. In this embodiment, the CRT display screen is divided into 56 display areas of 8 rows and 7 columns, as shown in FIG.
Symbol patterns, input/output addresses, and usage data are displayed in two display areas, and each display area is divided into 24 small blocks arranged in 6 rows and 4 columns as shown in Figure 7. It is now possible to specify the numbers and patterns to be displayed for each block. For this reason, the refresh memory 22 is provided with 48 x 28 storage areas, and addresses are specified using column addresses from C00 to C75 and row addresses from R00 to R63. . Symbols for displaying input/output elements such as contact symbols are displayed by a combination of multiple patterns as shown in Figure 7.
In this embodiment, the character generator 23 is designed so that when an ASCII code corresponding to a lowercase alphabet a to t is written into the refresh memory 22, a pattern as shown in FIG. 8 is displayed. By combining these codes and writing them into the refresh memory 22, a predetermined symbol can be displayed. For example, when displaying the display area of column C1 and row R2 on the display screen as shown in FIG. Just write the data. The display control circuit 26 reads data of the sequence program written in the buffer memory 21 and data for display, and writes data for displaying the sequence program written in the buffer memory 21 to the refresh memory 22. It is composed of a microcomputer. The memory 27 stores a control program for controlling the operation of the display control circuit 26, as well as a symbol pattern corresponding to the command word of the sequence program, a symbol pattern specified by the invalid command, and a control program for controlling the operation of the display control circuit 26. In order to display the usage code, a conversion table as shown in FIG. 10 is stored. This conversion table stores display data corresponding to the command word, display data corresponding to the symbol change code, and display data corresponding to the usage display code. It is read out by the display control circuit 26 according to the sequence program and stored in the refresh memory 2.
2, and the symbols and usage codes of input/output elements are displayed. FIG. 11 is a flowchart showing a control program that controls the operation of the display control circuit 26, and the reading of the sequence program related to the output element specified by the digital switch DS1 is completed, and the reading from the program reading circuit 20 is completed. This program is executed when the signal RIF is sent. First, in step 30, the read counter ROC that specifies the read address of the buffer memory is reset, and then display data such as the bus line displayed on the screen is written into the refresh memory 22, and the process moves to step 31. At step 31, 1 is added to the read counter ROC to make the count value 1, and at step 32, the data of the sequence program stored at the address specified by the read counter ROC is read out. In this case, the fifth
As shown in the figure, at address 1 of buffer memory 21,
Since the program data of TN0110 is stored, this program data of TN0110 is read out. At step 33, it is determined whether the data has been read out. If the data has not been read out, the process returns to the main routine (not shown) and enters a waiting state; if the data has been read out, as in this case, the process returns to step 3.
Move to 4. Step 34 is a step for determining whether or not the read sequence program is an invalid instruction NOP. If it is an invalid instruction NOP, the process moves from step 34 to step 42.
If the instruction is not an invalid instruction NOP, the process moves to step 35. In this case, since the instruction is not an invalid instruction NOP, the process moves to step 35. Step 35 is an area for setting the display area. Initially, column address C1 and row address R are set.
1 display area is set. When the setting of the display area is completed in this way, the process moves to step 36, where the command word is decoded, and in step 37,
Data for displaying a symbol pattern according to the decoded command word is written into the refresh memory 22. Writing of this data is performed with reference to the conversion table shown in Figure 10, and when the instruction word is TNO as in this case, the data of aaghaa to display the normally open contact is set. The data is written to storage areas in the refresh memory 22 corresponding to the six display blocks in the third column from the top in the display area. When writing to the refresh memory 22, a switching command signal is sent to the gate circuit 28 so that the refresh memory 22 can be accessed by the display control circuit 26. Next, at step 38, the data in the input/output address part of the sequence program data is set to 8.
Convert it to a base number, and in step 39, convert the converted octal input/output address data to column address C.
1. Write to the storage area corresponding to the four display blocks from the left of the display block in the second column from the top of the display area of the row address R1. Furthermore, at step 40, the on/off of the input/output element is determined based on the data indicating the on/off of the input/output element read together with the sequence program, and if the input/output element is on, the specified display area is The data for displaying the * mark in the rightmost block of the block in the column is written to the refresh memory 22, and then step 41 is performed.
Move to. Step 41 is a step to determine whether the instruction word is TNE, and in this case,
Since it is not TNE, step 41 to step 3
Return to 1. Returning to step 31, the read counter ROC
is incremented, and the data stored at address 2 of buffer memory 21 is read out. Since the data of NOP1, 1 has been written to address 2 of the buffer memory 21, steps from step 34 to step 42 are performed.
The process moves to change the symbol and display the purpose. That is, when step 42 is reached, the invalid instruction
Code data 0001 for symbol change programmed in the upper 5 bits of the operand part of NOP
In step 43, symbol display data aaklaa for displaying the symbol of the normally open pushbutton switch corresponding to code data 0001 is read out from the conversion table, and in step 44, the symbol display data aaklaa is read from the conversion table from above the specified display area. The read display data aaklaa is written into the storage area corresponding to the display block in the third column, that is, the storage area where the contact display data aaghaa was written in step 37. As a result, data aaghaa written by the instruction word of the sequence program is rewritten to data aaklaa. In the following step 45, the invalid command NOP
The code 0000001 for displaying the usage written in the lower 7 bits of the data in the operand part of is read out, and in step 46, this read data is read out.
Search the conversion table for display data KIDOU corresponding to 0000001. Then, in step 47, it is determined whether the most significant digit of the usage display code is 1. If it is 1, the process moves to step 48 to write the display data, and if it is 0, the process moves to step 49. , and write the display data. When the process moves to step 48, display data is stored in the storage area corresponding to the rightmost display area of the column where the currently designated display area is located.
When KIDOU is written and the process moves to step 49, the display data KIDOU is stored in the storage area corresponding to the top row of the currently designated display area.
is written. In this case, since the most significant digit is 1, the process goes to step 49 and the display data is stored in the storage area corresponding to the currently designated display area.
KIDOU is written. When the writing of the data for purpose display is completed in this way, the process proceeds to step 31 via step 41.
Return to the third sequence program TNE1
30 reads are performed. Since this sequence program is not an invalid instruction NOP, step 34 is executed.
The process then moves to step 35, where a display area is specified. In this case, since the previous sequence program is a TNO instruction, the display area is set below the previous display area. Once the display area has been set in this manner, display data is written in the same manner as in the case described above. In this case,
Since the invalid command NOP program is not added, the symbol pattern will not be changed and the symbol pattern of the contact will be displayed. Once the display data has been written in this way,
The process moves to step 41, but in this case, since the command word is TNE, the process returns to step 31 via step 50. Step 50 stores auxiliary display data for displaying a plurality of input elements connected in parallel in a storage area corresponding to the display area on the right side of the display area where display data is currently being written. In the writing step, control is performed to write predetermined pattern data into the corresponding position of the refresh memory 22. Next, the fourth sequence program TNA1
When 12 is read out, the display area is shifted one line to the right and display data is written. In this case, this sequence program is followed by an invalid instruction.
Since NOP4 and 2 are programmed, the display data 4 and 2 of this invalid command change the symbol pattern display data to data that displays a normally closed limit switch, and additionally displays the usage data of LS1. Display data LS1 for
is written into the refresh memory 22. Further, when the sequence program of the TNA 100 is read out, the display area is shifted to the right by one line, and display data for displaying a normally open contact is written. And output command YON13
When the sequence program 0 is read out, the display area is shifted to the right by one line to display a horizontal line, and then the display area is further shifted to the right to display the display area at column address C6 and row address R1. Display data for displaying relay symbols and input/output addresses is written into the corresponding storage area. In addition, in this case, there is an invalid instruction NOP after the output instruction, and the operand part of this invalid instruction is programmed with a code for displaying the purpose of displaying JIGAD in the right margin, so the display area is specified on the right. , and the JIGAD display data is written to the storage area corresponding to the moved display area. The above operation is performed in an extremely short time, so if you select the input/output address of the output element on digital switch DS1 and start operation, the relay diagram shown in Figure 12 will be displayed on the CRT screen instantly. be done. In the ladder diagram displayed on the CRT screen, pushbutton switches, limit switches, etc. are each displayed with a unique symbol, and the purpose of the circuit and the name of the input element are also displayed, as well as the on/off status of the input element. Ru. For this reason,
If you want to investigate the cause of a failure, you can instantly determine the cause. For example, if the jig does not move forward even if the start button is pressed in the start circuit for moving the jig forward described above, the display screen shown in Figure 12 can be obtained by setting the input/output address of relay CR10 to digital switch DS1 and monitoring. . If you look at this screen and LS1 is not turned on, you will immediately know that the limit switch LS1 is malfunctioning, and if the pushbutton switch labeled KIDOU does not turn on even if you press the start button, start the switch. It can be determined that the push button switch for the On the other hand, conventional display devices that display circuits using relay contacts and relay symbols and add only input/output addresses cannot determine failures in such a short time. In other words, with ladder diagrams displayed on conventional sequence display devices, it is impossible to know which contacts correspond to limit switches installed in control equipment or pushbutton switches on the operation panel. This is because when making a determination, it is necessary to refer to a program sheet or the like and find out which contact corresponds to what. Note that in the above embodiment, both the symbol pattern change and the usage code are displayed using the invalidation command, but even if only one of them is performed, it can be useful for determining the location of the failure. be able to. Further, when the failure location is not determined, the on/off state of the input element may not be displayed. Furthermore, in the above embodiment, the invalid command was used to program the data for commanding the change of the symbol pattern and the display of the usage code, but if the number of bits per word of the sequence memory 10 is increased, These data can also be programmed to the same address as the sequence program data. As described above, in the sequence display device of the present invention, the sequence program data read from the memory of the sequence controller,
Since the display pattern data is generated and displayed using both the display data added to this sequence program,
By simply adding simple data during a sequence program, you can change the symbols of input and output elements,
It becomes possible to display additional data such as a usage code. Therefore, by simply adding a simple program, the ladder diagram output on the screen of the display device can be made into a form similar to the actual relay circuit diagram, which has the advantage of making it easier to monitor for fault diagnosis and the like.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is a block diagram showing a state in which a sequence display device is connected to a sequence controller, FIGS. 2a and 2b are diagrams showing bit patterns of sequence program data, and FIG. 4 shows a sequence program corresponding to the relay circuit shown in FIG. 3, and FIG. 5 shows a sequence program shown in FIG. 4 in the buffer memory 2.
Figure 6 shows the display area on the CRT screen, Figure 7 shows the display blocks in each display area, and Figure 8 shows the status of relays, pushbutton switches, etc. FIG. 9 is a diagram showing a pattern used to display symbols, FIG. 9 is a diagram showing display data written in the refresh memory 22, and FIG. 10 is a diagram showing a conversion table stored in the memory 27. 11 is a flowchart showing the operation of the display control circuit 26, and FIG. 12 is a diagram showing a CRT screen on which a ladder diagram is displayed. 1...Sequence controller, 2...Sequence display device, 10...Sequence memory, 20
... Program reading circuit, 21 ... Buffer memory, 22 ... Refresh memory, 23 ... Character generator, 24 ... Timing signal generation circuit, 25 ... Video signal generation circuit, 26 ... Display control circuit, 27 . . . Memory, 42 to 44 . . . Steps for changing symbols according to display data, 45 to 49 . . . Steps for displaying usage according to display data, CRT . . . Cathode ray display tube.

Claims (1)

[Claims] 1. A sequence display device that displays a sequence program stored in a memory, etc. of a sequence controller in the form of a ladder diagram, in which sequence program data related to a specific output element is added to the sequence program data from the memory. A readout means for reading together with display data that is invalid for the programmed sequence control, and generation of display pattern data based on both the sequence program data and display data read by the readout means. and a display means that inputs the pattern data generated from the pattern data generating means and externally displays the symbol pattern, and is used to display or use symbol patterns that cannot be displayed from sequence program data. A sequence display device characterized in that it performs display, etc.