JPS6112563B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a step-by-step programmable sequence controller. The command system of recent step-by-step programmable sequence controllers is generally as follows. The commands for each process unit include output control commands that indicate whether to turn each output on or off during the execution period of that process, and processes that indicate the conditions for proceeding with the process and operation details for process advancement such as jumps and returns. The instructions for each process stored in the program storage section are sequentially issued and decoded and executed by the arithmetic control section. The above process update instruction consists of an instruction code that represents the type of processing operation, and modification data that modifies this instruction code to specifically specify the content of the processing operation, and the data length and storage of these instruction codes and modification data. Of course, the allocated areas in each section are determined. For example, in the case of an AND instruction that proceeds to the next process when the logical product (AND) of input signals from two specified input terminal numbers is established, the above instruction code area will contain a specific code representing the AND instruction, and the above Two input terminal numbers to be ANDed are entered in the modification data area. Furthermore, in the case of a timer instruction that proceeds to the next step after a specified time, the instruction code area contains a code representing the timer instruction, and the modification data area contains time data. For example, in a conventional sequence controller, the modification data is composed of a four-digit binary coded decimal code, and is divided into two areas each containing two digits (referred to as first and second areas). In the case of the above AND instruction, the first of the qualifying data,
Input terminal numbers are set in the second area, and in the case of the above timer command, time data in minutes is set in the first area, and time data in seconds is set in the second area. . As mentioned above, instructions for each process unit are expressed according to a predetermined format, so
Naturally, there are limits to the content that can be processed with one instruction. For example, with the AND instruction mentioned above, it is not possible to perform an AND process with three or more input terminals that specifies three or more input terminal numbers and proceeds with the process based on their logical product conditions.Also, with the timer instruction mentioned above, it is not possible to perform an AND process with three or more input terminal numbers and proceed with the process based on their AND conditions. Timer+AND processing, which advances the process when the conditions and the AND conditions of the specified input terminal number are met, cannot be performed. In order to implement such complex processing that cannot be processed with a single instruction, conventionally a special instruction (called a two-word instruction) that performs the processing of one step using instructions for two steps has been used. Defined. For example, a 4-input AND instruction as mentioned above, a timer +
In addition to the 2-input AND instruction, several types of processing operations that are considered to be versatile are selected, and the instructions for performing the processing are defined in a predetermined format using an instruction area for two steps. -ing Of course, in this case, other normal instructions (instructions that express everything in one process instruction area)
In addition to distinguishing between 2-word instructions and 2-word instructions, an instruction code corresponding to the processing content is required for each 2-word instruction. For this reason, conventionally, when the number of types of two-word instructions is increased in order to perform various more complex processes, the number of types of instruction codes increases accordingly. This greatly impairs the ease of programming.
In particular, an important feature of step-by-step controllers is that they can be easily used even by ordinary people without specialized knowledge of control technology, and by enriching the functions, programming can be made easier. Complication is not a good thing. in general,
Increasing the number of command keys on a program console gives users a strong impression that programming is difficult. Furthermore, processing operations that cannot be expressed using two-word instructions can be expressed using three- or four-word instructions, but if it is important not to increase the number of instruction codes as mentioned above, two-word instructions are acceptable. This is the limit of what is possible. In other words, it is not difficult to increase the number of functions without pursuing ease of programming, but it is not easy to increase the number of control functions without sacrificing ease of programming. This invention was made against the above technical background. In this invention, processing contents that cannot be expressed by a process update instruction for one process are expressed using instructions for two or more processes (this is called a multi-word instruction). Rather than assigning unique instruction codes to the processing content of word commands, we adopted the following configuration and control method. That is, the configuration is such that specific data indicating whether or not it is a "continuation instruction" can be added to each process update instruction, and the process update instruction (process number N) modified with this specific data as a "continuation instruction" is executed. Sometimes, process update instructions for (i+1) processes up to a process update instruction (process number N+i) that is not qualified as a "continuation instruction" in the following process update instructions are processed as one multi-word instruction, and this multi-word instruction is processed as one multi-word instruction. Process number N+i+1 according to the conditions expressed in the command
The system now controls the transition to . Therefore, although it is possible to perform various process step processes by combining multiple normal process update commands, the amount of specific data (1 bit data is sufficient) for defining "continuation commands" is increased. This makes it possible to support a variety of control specifications without complicating the program console. Further, in this invention, a process number display, an instruction code display, a preset number of modification data displays, and a continuation instruction data display are arranged on the front panel of the controller housing in accordance with the input order during programming. Therefore, the operation of adding 1-bit specific data indicating that the instruction is a continuation instruction can be easily performed based on the well-known normal operation of this type of step-by-step programmable sequence controller. Also from this point of view, control functions can be added without compromising ease of programming. Hereinafter, one embodiment of the present invention will be described in detail based on the drawings. FIG. 1 is a block diagram showing the electrical configuration of a sequence controller according to the present invention, and FIG. 2 shows its external appearance. This sequence controller includes a central processing unit 2 composed of a so-called microcomputer made into firmware,
An input circuit 3 is an input interface between an external contact connected to the input terminal IN and the central processing unit 2.
, an output circuit 4 that controls an external device connected to the output terminal OUT according to an output signal from the central processing unit 2, a program storage section 5 that stores a sequence program arbitrarily set by the user, and a program storage section 5 that stores a sequence program arbitrarily set by the user; A key input device 6 used for
Display 7 that displays the command being set when setting a program, and the command being executed when executing the program.
etc. User commands for each process unit in this sequence controller are configured in the format shown in the table below.

[Table] The instruction code "OP" has 4 bits and represents the type of processing operation. The modification data "DATA-1" and "DATA-2" are each 8 bits (2-digit binary coded decimal code, the modification data as a whole is a 4-digit binary coded decimal code), and the instruction Specify specifically the type of processing operation represented by the code. The continuation instruction code "CONT" is 1-bit data newly added in this invention. When programming as the above-mentioned multi-word instruction, the continuation instruction code "CONT" is set to "1", and normally it is set to "0". (corresponding to this, the key input device 6 is provided with a key for setting the continuation command code "CONT"). Also, the output control command “OUT”
is data with the same number of bits as the number of output terminals in one-to-one correspondence with each output terminal, and represents on/off of each output terminal, respectively. Corresponding to this command format, the display 7
As shown in Fig. 2, there is a two-digit numerical display ₇₁ that displays the process number (step number), and a one-digit numerical display ₇₂ that displays the decimal converted instruction code "OP". , a total of four digit numerical displays 7 ₃ and 7 ₄ that convert and display the modification data "DATA-1" and "DATA-2" in decimal, and an LED lamp 7 that displays the continuation instruction code "CONT" in binary. ₅
and a group of LED lamps _76, etc., which respectively display the output signal status of each output terminal OUT. Next, general instruction codes and their execution contents in this programmable controller will be briefly explained. (a) "NOP"; Non-operation command Proceeds to the next process number without doing anything. (b) “END”; End command Indicates that one cycle of processing has ended. (c) "JMP"; Jump command Jumps to the process number specified in "DATA-1" and continues execution from there. Also, if the input terminal number is programmed in "DATA-2", the input specified in "DATA-2" will be received, the process will jump to the process number specified in "DATA-1", and the execution will continue from there. . (d) "AND"; AND instruction When the input signals of the two input terminal numbers specified as "DATA-1" and "DATA-2" are aligned, proceed to the next step number. (e) "OR"; OR instruction Receive the input signal that comes first from the two input terminal numbers specified as "DATA-1" and "DATA-2" and proceed to the next process number. (f) "CNT"; Count instruction "DATA-1" is the number specified in "DATA-1".
-2" is counted, and when the count is up, the process proceeds to the next process number. (g) "CJP"; Conditional jump command If the input signal of the input terminal number specified as "DATA-2" is on, jumps to the process number specified as "DATA-1" and the above input signal is turned off. In this case, proceed to the next process number. (h) “RPT”; Repeat command Repeats from the process number specified in “DATA-2” to the current process number up to the number of times specified in “DATA-1”. (i) "TIM"; Timer command When the time specified in "DATA-1" and "DATA-2" has elapsed, proceed to the next process number. The above is a very well-known instruction code,
The signal processing procedures used to perform this procedure are also well known and will not be described in detail. The controller according to the present invention is based on the well-known command system and processing method as described above,
To this end, a new control method, which will be explained below, has been introduced. The new method is that when executing an instruction for which the continuation instruction code “CONT” is “1”, “CONT” = “CONT” in the following process update instruction.
The point is that instructions for multiple steps up to the instruction that is "0" are processed as one multi-word instruction. The third example specifically shows this new control method.
This is a flowchart of the figure. FIG. 3 is a flowchart showing a part of the basic operation of the central processing unit 2, which is defined by the system program stored in the ROM in the central processing unit 2. In particular, it focuses on the execution process of subsequent instructions related to the main part of the present invention. It is expressed in The following will explain according to this flowchart, but first, the terms used in this flowchart (names given to various data areas allocated to the RAM in the central processing unit 2) will be explained. . Process counter PC: This is a storage area for process numbers addressed to the program storage unit 5. Instruction register R1: This is an area for storing instructions for one process read from the program storage section 5. Leading number register R2: This is an area for storing the step number of the leading instruction among the instructions for multiple steps constituting a multi-word instruction. Status register R3: This is an area where one of the four status codes of "reset", "start", "continuation", and "end" is stored. When the instruction being processed is a normal instruction (not a multi-word instruction), it is set to "reset", when it is the first instruction in a multi-word instruction, it is set to "start", and when it is an intermediate instruction among multi-word instructions, it is set to "start". It is set to ``Continue'' and set to ``End'' for the last instruction in a multi-word instruction. Status register R4: This is an area in which one of two status codes indicating the fulfillment of a condition expressed by a multi-word instruction is stored. Next, the flowchart shown in FIG. 3 will be explained in order. In this example, among the instructions mentioned above,
You can use multiple of the four types of instructions: OR instruction (OR), AND instruction (AND), count instruction (CNT), and timer instruction (TIM) (you can use multiple of the same instruction,
(Commands of different types may be combined) to form a multi-word command. The operation contents of each routine in FIG. 3 are as follows. Routine 1: Addresses the program storage unit 5 with the process number stored in the process counter PC, reads out the user command (process update command and output control command) of that process number, and stores it in the command register R1. Routines 3 and 6: Determine whether or not the subsequent instruction code "CONT" is "1" for the instruction stored in the instruction register R1. Routines 2, 17, 22... Determine whether status register R3 is set to "reset". Routine 23... It is determined whether the status register R3 is set to "start". Routine 18...Determines whether the status register R3 is "completed". Routine 19...Set the status register R3 to "reset". Routine 4...Store the "start" code in status register R3. Routine 7...Store a "Continue" code in status register R3. Routine 8...Store the "end" code in status register R3. Routine 5...Stores the process number in the process counter PC into the first number register R2. Routine 21: Set the process number in the head number register R2 in the process counter PC. Routines 15, 24...Set the status register R4 to the "established" state. Routine 16...Status register R4 is "not established"
Reset to state. Routine 20...Determines whether status register R4 is set to "established". Routine 25... Add 1 to the process number of the process counter PC (step the process). Routines 26, 27...The output circuit 4 is operated according to the output control command "OUT" among the commands stored in the command register R1. Routine 9...Decodes the instruction code "OP" of the instruction stored in the instruction register R1, and distributes control according to each instruction code. Routine 10...In the OR instruction execution routine, check the input status of the two input terminal numbers specified by the modifying data "DATA-1" and "DATA-2" in the instruction stored in the instruction register R1. , it is determined whether the OR condition is satisfied. Routine 11: AND instruction execution routine.
Checks the input states of the two input terminal numbers specified by the modification data "DATA-1" and "DATA-2" in the instruction stored in the instruction register R1, and determines whether the AND condition is satisfied. do. Routine 12...In the execution routine of the count instruction, it is checked whether the input signal of the input terminal number specified by the modification data "DATA-2" in the instruction stored in the instruction register R1 has risen, and if the rising When detected, a predetermined counter is incremented, and it is further determined whether the count value of the counter has reached the value specified by the modification data "DATA-1". Routine 13...A timer instruction execution routine.
A predetermined clock signal is counted by a predetermined counter, and the counted value is stored in the instruction register R1.
Modified data “DATA−” in the instruction stored in
1" and "DATA-2" is reached. Routine 14...This routine is collectively shown as an execution routine for instructions other than the above four types of instructions.
This routine 14 not only determines whether the conditions of the above-mentioned JMP, CJP, and RPT instructions are met, but also controls the operation of the output circuit 4 with the output control command "OUT" similarly to the routine 27, and similarly to the routine 25. It includes control for incrementing the process counter PC or setting the process number specified by the JMP, CJP, or PRT command in the process counter PC. Next, the flow of control according to this flowchart will be explained according to a specific example of a user program shown below.

[Table] The instruction with process number 05 in the program shown in Table 1 is a normal timer instruction with “CONT” = “0”, which continues the output state of the output control instruction OUT (05) for 12 minutes and 34 seconds, and then This indicates that the process is proceeding to step 06. This command is processed as follows. First, control is started from routine 1 with the contents of the process counter PC set to "05". Note that as an initial state, the status register R3 is "reset" and the status register R4 is "not established." Therefore, routine 1 → routine 2
YES → NO at Routine 3 → Routine 9 → Routine 13, count the time, and until it reaches 12 minutes 34 seconds, NO at Routine 13 → Routine 1
6→routine 17, YES→routine 26→routine 9 are repeated, and the output state of the output circuit 4 is determined at OUT (05). When the time reaches 12 minutes and 34 seconds, YES in routine 13 → YES in routine 22
YES→routine 25, the process number of the process counter PC is incremented to "06", and the process returns to routine 1. In the program in Table 1, the instruction for step number 06 is
This is a normal OR command with "CONT" = "0", which indicates that the output state is set according to the output control command OUT (06) until the OR condition of the input signals of input terminal numbers 21 and 22 is satisfied. In this case, routine 1
→ YES in routine 2 → NO in routine 3 → Routine 9, and until the OR condition is satisfied, NO in routine 10 → YES in routine 17 → Routine 2
6→routine 9 is repeated, and when the OR condition is satisfied, the routine proceeds as follows: YES in routine 10→routine 15→YES in routine 22→routine 25, the process counter PC is incremented to "07", and the routine returns to routine 1. In the program shown in Table 1, the instruction with step number 07 is an AND instruction, but the continuation instruction code "CONT" is "1". In other words, this indicates that this instruction is the first instruction of a multi-word instruction. The following instruction with step number 08 is also an AND instruction,
"CONT" is set to "1", indicating that this instruction is also part of a multi-word instruction. The following instruction with step number 09 is a timer instruction, and "CONT" is set to "0", indicating that this instruction is the last instruction of the multi-word instructions. That is,
"CONT" indicates that a three-word instruction is composed of instructions for three steps with process numbers 07, 08, and 09. The contents are the AND condition of two inputs of input terminal numbers 01 and 02 specified by "DATA-1" and "DATA-2" of process number 07, and "DATA-1" and "DATA-1" of process number 08. The AND condition of two inputs of input terminal numbers 03 and 04 specified by ``-2'' and ``DATA-1'' and ``DATA-'' of process number 09.
2) When all of the timer conditions of 2 minutes and 30 seconds elapsed specified in "2" are met (that is, when the AND condition of the 4-input AND condition and the timer condition is met), proceed to step number 10 and the condition is met. Until then, the output state is determined by the output control command OUT (09) of process number 09. Note that in the case of a multi-word instruction, the output control instruction is set only in the last instruction. Control in this case proceeds as follows. [A] ...The instruction with process number 07 is read in routine 1 → YES in routine 2 → YES in routine 3
YES → Routine 4 → Routine 5 → Routine 9
→Proceed to Routine 11. Assuming that the two-input AND condition for input terminal numbers 01 and 02 is not satisfied,
NO in routine 11 Routine 16 → Routine 1
The process progresses from NO at 7 to NO at routine 18 to routine 25, and the process counter PC is incremented to “08”.
Return to routine 1. [B] ...The instruction with process number 08 is read in routine 1 → NO in routine 2 → NO in routine 6
YES → Routine 7 → Routine 9 → Routine 1
Proceed with 1. Assuming that the two-input AND condition for input terminal numbers 03 and 04 is not satisfied, routine 11
The process progresses as follows: NO → Routine 16 → NO at Routine 17 → NO at Routine 18 → Routine 25, the process counter PC is incremented to "09", and the routine goes to Routine 1.
Return to [C] ...The instruction with process number 09 is read in routine 1 → NO in routine 2 → NO in routine 6
→ Routine 8 → Routine 9 → Routine 13. If 2 minutes and 30 seconds have not passed, Routine 1
NO at 3 → NO at routine 16 → NO at routine 17 →
YES in routine 18→routine 27→routine 19→NO in routine 20→routine 21, and “07” is set in the process counter PC.
Return to routine 1. Therefore, if none of the AND condition of process number 07, the AND condition of process number 08, and the timer condition of process number 09 are satisfied, the above [A] → [B]
→ [C] control is repeated. For example, if only the AND condition of step number 07 is satisfied, in the control of [B] above,
The routine proceeds as follows: YES in routine 11 → NO in routine 22 → YES in routine 23 → routine 25, the status register R4 becomes "established", the process counter PC becomes "08", and the process returns to routine 1. However, if the other conditions are not satisfied, the above-mentioned control [B]→[C] is performed, and the status register R4 is set to "unsatisfied". Furthermore, if the AND condition of step number 08 is satisfied, in the control of [B] above, routine 11
YES in routine 22 → NO in routine 23
→NO in routine 18→Proceed to routine 25. In other words, neither routine 16 nor routine 24 is passed;
Does not change the state of status register R4. Therefore, if the AND condition of process number 07 and the AND condition of process number 08 are both satisfied, the control in [C] is entered with the status register R4 set to "established". At this time, if the timer condition is also satisfied, YES in routine 13 → YES in routine 22
NO→NO in routine 23→YES in routine 18→
Routine 27 → Routine 19 → Routine 20
The process advances from YES to routine 25, and the process counter PC is incremented to "10" for the first time. Note that the instruction with step number 10 in the program in Table 1 is a normal count instruction with “CONT” = “0”.
Since this execution procedure can be easily understood from the flowchart of FIG. 3 and in accordance with the above explanation, it will not be described in detail. Next, the OR instruction, the AND instruction, the count instruction,
Another example of a multi-word instruction using a combination of timer instructions will be explained.

[Table] In the program shown in Table 2, from the first instruction with step number 12 where “CONT” becomes “1” to the instruction with step number 15 where “CONT” becomes “0” in the following instructions. A four-word instruction is composed of instructions for a total of four steps. The content is that when the 6-input OR condition of input terminal numbers 01, 02, 03, 04, 05, and 06 is satisfied, or the 2-input AND condition of input terminal numbers 07 and 08, the process number is set to "16". ”, and until then the output control command OUT
(15) determines the output state. The execution procedure of this four-word instruction is shown in the flowchart of FIG.

[Table] In the instructions in Table 3, step numbers 22 and 23, 2
A two-word instruction is made up of instructions for the steps.
The content is that when both the timer condition of 10 minutes elapsed for process number 22 and the count condition of counting the signal from input terminal number 05 of process number 23 30 times are met, the process number is changed to "24". proceed to,
That is what it is. The execution procedure for this is shown in the flowchart of FIG. Note that in the above embodiment, a multi-word instruction can be configured using four types of instructions: an OR instruction, an AND instruction, a count instruction, and a timer instruction. However, the present invention is not limited to this; Other instructions can also be treated as components of an instruction. As explained in detail above, according to the control method of the step-by-step programmable sequence controller according to the present invention, complex processing contents that cannot be expressed with ordinary instructions for one process can be achieved by combining instructions for multiple steps. can be expressed and executed as a multi-word instruction. At that time, instead of increasing the number of instruction codes that represent the type of processing operation, we added an instruction code (one bit is enough) to the normal instruction code to configure a multi-word instruction, so the instruction system This allows various sequence control processes to be performed without complicating the process. In other words, it is possible to control process progress based on complex conditions using multi-word commands, but the number of command codes does not increase accordingly; instead, the number of types of command code keys on the program console (key input device) increases significantly. This greatly reduces the possibility that the user will feel that programming is difficult. Furthermore, in the present invention, by operating one specific key attached to the front panel of the controller housing in parallel with the instruction code key, it is possible to indicate whether or not the process step instruction is a "continuation instruction" or not. It is configured so that 1-bit specific data can be added, and the front panel has a process number display, an instruction code display, a preset number of modification data displays, and a continuation instruction data display for input during programming. Because they are arranged in accordance with the order, the normal input order for the process number display, instruction code display, and a preset number of modification data displays is not changed in any way. An extremely simple operation of simply adding an input operation can be taught to the user in an easy-to-understand manner, and the user can easily perform the input operation.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the electrical configuration of a sequence controller according to the present invention, FIG. 2 is an external view thereof, and FIG. 3 is a flow chart showing the basic operation of the same controller. 2...Central processing unit, 3...Input circuit, 4...
Output circuit, 5...Program storage unit, 6...Key input device, 7...Display device, 7 ₁ ...Process number display device, 7 ₂ ...Instruction code display device, 7 ₃ , 7 ₄ ...
Modification data display, 7 ₅ ...Continued command data display, CONT...One specific key.

Claims (1)

[Scope of Claims] 1. A process step instruction that expresses conditions for moving from one process to another process includes an instruction code that expresses the type of processing operation, and a process that specifies the type of processing operation expressed by this instruction code. sequentially reads and deciphers the process marching instructions stored in the program storage unit in correspondence with process numbers,
In the step-by-step programmable sequence controller that is to be executed, the process update command is executed as a "continuation command" by operating one specific key attached to the front panel of the controller housing in parallel with the instruction code key. The front panel is configured to be able to add 1-bit specific data indicating whether or not there is a process number, an instruction code indicator, a preset number of modification data indicators, and continuation instruction data. The display units are arranged in accordance with the input order during programming, and when executing the process update command (process number N) modified with the above specific data as "continuation command",
The process update instructions for (i+1) processes up to the process update instruction (process number N+i) that is not qualified as "continuation instruction" in the following process update instructions are processed as one multi-word instruction, and this multi-word instruction 1. A control system for a step-by-step programmable sequence controller, characterized in that the process is moved to step number N+i+1 according to expressed conditions.