Mitsubishi Electric MELSEC L series, Руководство по программированию

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3 HANDLING OF CHARACTERS AND NUMERIC VALUES IN ST PROGRAMS
3.3 Data Representation Methods
Constants, labels and devices can be used as data in ST programs.
Item Description
Representation
Example
Constant Numeric value or character string data written directly to
a program. It does not change during program execution.
123, “ABC”
Label Data whose type and name are defined by the user. Switch_A
Device Device used by the QCPU (Q mode)/LCPU. It is
identified by the device name and device number.
X0, Y0, D100, J1\X0
3.3.1 Constants
Each constant is represented as described below in ST programs.
Data Type Numeric Notation Representation Method Example
TRUE • FALSE 1•0 M0 := TRUE;
Binary The used binary number is preceded by "2#". M0 := 2#0;
M0 := 2#1;
Octal The used octal number is preceded by "8#". M0 := 8#0;
M0 := 8#1;
BOOL
Hexadecimal The used hexadecimal number is preceded
by "16#". M0 := 16#0;
M0 := 16#1;
Binary The used binary number is preceded by "2#". D0 := 2#110;
Octal The used octal number is preceded by "8#". D0 := 8#377;
Decimal The used decimal number is preceded by
"10#".
(The numeric value may be preceded by "K".) D0 := 123;
D0 := K123;
INT
DINT
Hexadecimal The used hexadecimal number is preceded
by "16#".
(The numeric value may be preceded by "H".) D0 := 16#FF;
D0 := HFF;
REAL
The used real number is directly input.
(The numeric value may be preceded by "E".) ABC := 2.34;
Rtest := E2.34;
STRING A character string is enclosed by ' ' (or " ").
Stest := 'ABC';
Stest := “ABC”;
For the range that can be specified for each constant, refer to Section 3.2.1 Data types.
The following ranges apply to the areas that are not described in Section 3.2.1 Data types.