GB2099667A

GB2099667A - Programming system with CRT and display unit

Info

Publication number: GB2099667A
Application number: GB8205997A
Authority: GB
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 1981-03-03
Filing date: 1982-03-02
Publication date: 1982-12-08
Also published as: SE454470B; GB2099667B; SE8201279L; DE3207660A1; AU8100782A; JPS57164302A; DE3207660C2

Abstract

A programming system includes a CRT and a keyboard input device. The keyboard 3 contains usual numerical and command keys, and in addition contains data instruction keys especially for use in programming. The program, written using the keyboard 3 is displayed on the CRT 2 in ladder diagram format, may be converted and input to a programmable process controller 13. The controller 13 can accept logical (high-low) process input signals and can produce similar output signals dependent on the inputs and on signals from timers and local memories. Data registers provide temporary store, the contents of which can be compared and manipulated as indicated in the displayed ladder diagram. <IMAGE>

Description

SPECIFICATION Programming system with CRT and display unit The present invention relates to a CRT display method and a programming system including a CRT, for inputting programs to a programmable controller.

The progamming system with the CRT is generally configured as shown in Fig. 1.

Namely, in Fig. 1, reference numeral 1' denotes a programming system with a CRT, which is provided with a CRT 2', a keyboard 3' and a control unit 4'. The system operates such that a ladder diagram such as that in Fig.2 is displayed on the face of the CRT 2' by operating the keyboard 3', and the data is converted into an instruction (or program) to be used on the programmable controller (hereinafter referred to as "PC") by the control unit 4' which is stored once in a program memory (not illustrated) in the programming system 1' and then inputted to PC 5' by operating the keyboard 3'.

Meanwhile, inputs and outputs to be controlled, like process inputs (abbreviated as "X"), process outputs (abbreviated as "Y"), timers (abbreviated as "T") and temporary memories (abbreviated as "M") of the PC 5' have been hitherto processed according to so-called sequence instructions, all as information in single bits, and expressed as a contact 7', b contact 8' and coil 9', as shown in Fig. 2, on the ladder circuit diagram.

However, there exist programmable controllers 5' having an instruction called data register (abbreviated as "D") which generally processes a plural bit of information (data), i.e., the so-called data instruction, and in this case, said data instruction may be expressed in a flowchart format, but has not hitherto been expressed on the CRT face in a ladder diagram format as in the case of sequence instruction.

The expression on the face of the CRT 2' in ladder diagram format is of advantage in improving programming of the PC 5' for operation, as compared with expressions in flowchart format.

The present invention thus provides an improvement whereby the above data instruction can be expressed on the CRTface in ladder diagram format, as in the case of sequence instruction, and one preferred embodiment will be described in detail hereunder. The data instruction referred to herein is an instruction to process a data register (D) which is a memory of plural bits of information.

Examples of such data instructions are as follows:

I = I D1 I D2 1 ( 1 ) Operation result shall be "1" where (D1)=(D2).

< D1 D1 DZ I (2) Operation result shall be "1" where (D1) < (D2).

> D1 D2 (3) Operation result shall be "1" where (D,) > (D2).

MOV D1 D2 | D2 1 (4) (D1) shall be transferred to (D2).

I + | D1 7 D2 i (5) (D1)+(D2) < (D2) Provided: 1. (D,) represents the contents of data register D18 2. (D2) represents the contents of data register D29 3. The operation result "1" represents a state wherein a contact is closed on the ladder diagram.

In the accompanying figures: Fig. 1 schematically illustrates the essential features of a programming system employing a CRT; Fig. 2 illustrates an instruction in the form of a ladder diagram; Fig. 3 is a drawing representing one preferred embodiment of a system according to the invention; Fig. 4 is a view of the arrangement of a keyboard for use with the system of Fig. 3; Fig. 5 is a sequence diagram illustrating keyboard operations in programming; Fig. 6 is a ladder diagram including data instructions; Fig. 7 illustrates the format of storage of circuit information; Fig. 8 illustrates a character code string; Fig. 9 illustrates the method of displaying various instructions; and Fig. 10 illustrates an example of the program corresponding to the Fig. 6 ladder diagram.

The keyboard 3 in Fig. 3 is constituted of a plurality of keys for displaying a ladder diagram on the CRT, and one embodiment thereof is shown in Fig. 4. In Fig. 4, data instruction keys 40 and data instruction circuit element keys 100 are not prepared for conventional keyboards and hence are those which are newly added. The other keys 20, 30 and 50 are commonplace control inputloutput number and symbol keys, and a "go" or processing start key, respectively.

Next, a keyboard control unit 6 in Fig. 3 functions to store operation data from the keyboard 3 in a circuit information memory 8 as circuit information. An example of the keyboard operating method or sequence for displaying the ladder diagram of Fig. 6 including data Instruction on the CRT is as shown in Fig. 5, and when the keyboard is operated as shown in Fig. 5, circuit information is stored in the circuit information memory 8 in the format shown in Fig. 7 by the keyboard cqntrol unit 6. In this case, the q X, 100, etc. symbols are actually stored in the form of a circuit information code of binary digits.

Next, a circuit informationecharacter code conversion control unit 11 in Fig. 3 functions to convert the contents (i.e., the circuit information code) of the circuit information memory 8 into a character code string like that shown in Fig. 8, and then stores this string in a character code memory 7. Details of the character code parts 7A, 8A, 9A, 1 OA and 1 OB of Fig. 8 are shown in Fig.

9.

In Fig. 9, 7A denotes the display for a contact; 8A, that for a b contact; and 9A, that for a coil, each being expressed by means of 6 characters on the CRT 2 from the keyboard shown in Fig. 4.

On the other hand, 1 OA and 1 OB denote the displaying data instructions, both being expressed on the CRT by means of 18 characters, corresponding in length to three contacts or coils.

Thus, Fig. 8 and Fig. 9, for the sake of convenience of description, illustrate the characters as displayed on the CRT, however, these will actually be stored in the memory 7 in a character code of binary digits corresponding to each character.

Next, a character generator 4 in Fig. 3 functions to generate the characters to actually be displayed on the CRT corresponding to the character codes stored in the character code memory 7, and a conversion from character codes to characters is carried out by the CRT control unit 5, which is then displayed on the CRT 2.

As described above, the ladder diagram like that illustrated in Fig. 6 is displayed on the CRT, through the keyboard operation sequence illustrated in Fig. 5.

An example of the program corresponding to the ladder diagram of Fig. 6 is given in Fig. 10. In Fig. 10, instructions LD X 100, LDI X 150, OR Ti 5 and OUT Y1 23 correspond to items 6A, 6B, 6C and 6D of Fig. 6, respectively.

Further in Fig. 10, an instruction string or program is illustrated for the sake of convenience in description, however, instruction codes corresponding to each instruction are stored in the program memory 9.

Now, the circuit information code stored in the circuit information memory 8 by the abovementioned means is converted into an instruction code by a circuit informationwinstruction code conversion control unit 12 and is then stored in the program memory 9. Also, information can be transferred and stored through conversion in unit 12 from 9 to 8, reversely.

Lastly, the instruction code stored in the program memory 9 by the control unit 10 for data transmission/reception with the PC can be transmitted to the PC 13. Also, reverse information flow may take place via the control unit 10.

According to the method described above, the keyboard-entered data is displayed on the CRT by way of elements 3o4o8o11e7o5 < 2, and can also be transmitted to the PC as an instruction code or program by way of elements 8e12e9 < 10e13. Then, the instruction code of the PC can be displayed on the CRT as a ladder diagram by way of elements 13e10e9 < 12e8e11 o7e5e2.

In the above example, data instructions are displayed by parenthesizing with a ] -shaped symbol, however, the symbols " < ", " > ", ", ", etc.

can be used as well.

Lastly, the ladder diagram (Fig. 6) will be described as follows.

First, the circuit on the upper line represents that when a process input No. 100 (X 100) goes "ON" (logical "1"), and (D 123) and (D 150) coincide, a coil of the process output 123 (Y 1 23) is excited. Then, the circuit on the lower line represents that when a process input No. 1 50 (X 150) goes "OFF" or a timer No. 15 (T 15) goes "ON", (D 20) is transferred to (D 30).

As described above, according to the invention data instructions for processing plural bits of information can simultaneously be displayed on a CRT in a ladder format, as in the case of a sequence instruction for processing one bit of information, thus greatly improving the programming method as compared with the conventional flowchart format.

Claims

1. A display method for a programming system including a CRT, a key-in input being effective on a keyboard having keys related with a ladder diagram, comprising displaying a program of a programmable controller having a data instruction to process plural bits of information simultaneously in addition to a sequence instruction to process one bit of information, input via said keyboard, on the CRT in ladder diagram format, and converting the program into an instruction for a program controller according to said displayed ladder diagram.

2. The display method as defined in claim 1, wherein the data instruction is displayed by parenthesizing with six ] -shaped symbols.

3. The display method as defined in claim 1, wherein the data instruction is displayed by parenthesizing with six < -shaped symbols.

4. The display method as defined in claim 1, wherein the data instruction is displayed by parenthesizing with six comma symbols.

5. A programming system, comprising: a CRT, an input keyboard having keys related with a ladder diagram; a memory for storing circuit information inputted through operation of said input keyboard, said CRT converting display information inputted through operation of said input keyboard into ladder diagram format, and a conversion control unit for converting said information into instructions for a program controller according to the ladder diagram displayed on said CRT.

6. The programming system as defined in claim 5, wherein said keys related with the ladder diagram are data instruction keys.

7. The programming system as defined in claim 6, information inputted through operation of the input keyboard being a program of the programmable controller having a data instruction to process plural bits of information simultaneously, in addition to a sequence instruction to process one bit of information simultaneously.

8. The programming system as defined in claim 7, wherein the CRT comprises a conversion control unit to convert circuit information inputted via the keyboard into a character code, a memory for storing the character code converted by said conversion control unit, a control unit for transmitting and controlling contents of said memory to a CRT body, the CRT body displaying a signal outputted from the control unit as a ladder circuit.

9. The programming system as defined in claim 8, wherein the instruction code converted by the conversion control unit is outputted to the program controller.