JPS628205A - Prorgammable controller - Google Patents

Abstract

PURPOSE:To describe conditional statements for conditional control graphically and to make the description of a program clear by generating the program in relay sequence symbols artificially. CONSTITUTION:Contents read out of a program memory 2 are decoded by being passed through a decoder 403 from the condition code part of an instruction register 401. Then, modified condition is supplied to AND gates 404-407 to select a necessary bit of an arithmetic relay buffer register 402. The on-off state of a relay specified by an OR gate 408 is taken out as one-bit information. A contact code (A/B), on the other hand, indicates whether the current relay position corresponds to a contact A or B. An execution destination discrimination circuit 412 discriminates whether a program described successively to the contact or a program described in a next line is to be executed according to the output of an OR gate 411.

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a programmable controller having arithmetic processing capability, and particularly to a programmable controller in which a program is written using relay sequence symbols. [Prior Art] A programmable controller is a stored program type control device that also controls arithmetic operations from a programmable controller. Conditional control functions are essential in such programmable controllers, and are generally programmed using assembler, basic language, or compiler descriptions. [Problems to be Solved by the Invention] However, such a description does not fulfill the mission of a programmable controller to graphically represent command words, making the program difficult to understand. [Means for solving the problems] The present invention has been made in view of the above points,
It has means for storing arithmetic operation results (plus, zero, minus, carry, etc.) in an arithmetic relay that turns on and off multiple bits corresponding to each result,
The contact is modified with the calculation relay number and condition, and if the corresponding condition bit of the relevant relay is on, the person's contact is closed and the B contact is judged to be open, and if it is off, the A contact is open and the B contact is judged as open. As long as the contact is closed, the written program is executed continuously, and when it becomes open, the written program is executed continuously as long as the contact is closed. The system is equipped with a means for solving the problem, such as executing the program written on the next line without executing the previous program. [Function] The present invention aims to solve such a problem, that is, to simulate it into a relay sequence symbol. This allows the description of conditional statements to be used as figures and has a special effect. Hereinafter, the present invention will be explained in detail based on the drawings. [Embodiment] Fig. 3 is a hardware diagram shown to facilitate understanding of an embodiment to which the present invention is applied, in which 1 is a program development device, 2 is a program memory, and 3 is a data memory. . Here, the OTL enclosed by the chain line decodes the command and
It shows the control device to be executed. That is, the program development device f1 is equipped with a keyboard and a display device and is used to create a program.Here, the program development device f1 is equipped with a keyboard and a display device, and is used to create a program using a command system in which conditional statements of a compiler in a computer according to the present invention are simulated with relay symbols. Become something to do. Then, the object code obtained by such program development device 1 is stored in program memory 2.
loaded into. Further, in the data memory 3, arithmetic relays each consisting of 4 bits for storing arithmetic operation results, 1-bit sequence relays for storing on/off states, arithmetic operation values, etc. are stored. Furthermore, the processing unit 4 reads instructions from the program memory 2 and performs arithmetic processing based on the contents. FIG. 1 shows a coding example of an embodiment according to the present invention, where (, ] are descriptors that declare the start and end of arithmetic processing, etc., 5 and 5' are A contacts, and 6 is a B contact. In Figure 1 ζ, in "row 1" there is a descriptor

〔Effect of the invention〕

As explained above, according to the present invention, it is possible to provide an exceptional programmatic pull controller in which the program description is clear by graphically representing the conditional statements in the co% byrer.

[Brief explanation of drawings]

1 and 2 are diagrams showing a coding example of an embodiment according to the present invention, and a circuit diagram showing the main part configuration of a processing section,
FIG. 3 is a hardware diagram shown to facilitate understanding of an embodiment to which the present invention is applied. 1...Flocrum development device, 2...Program memory, 3...Data memory, 4...
...processing section. 401...Instruction register, 4o
2... Arithmetic relay buffer register, 5.
5' River...II! , 6...B contact.

Claims (1)

[Scope of Claims] 1. A programmable controller equipped with the ability to process arithmetic calculations, characterized in that it has a command system in which conditional statements are simulated as relay sequence symbols. 2. The instruction system is provided with an arithmetic relay that turns on and off a plurality of bits that give meaning to the arithmetic operation result, and the execution state of the program written thereafter is changed by opening and closing of contacts modified based on the meaning of the plurality of bits. The programmable controller according to claim 1, wherein the programmable controller is configured to control.