Identifiers; Label Statement - Omron SCARA YRCX Series Programming Manual

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Identifiers

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LABEL Statement

1-4 Chapter 1 Writing Programs
"Identifiers" are a combination of characters and numerals used for label names, variable names,
and procedure names. Identifiers can be named as desired provided that the following conditions
are satisfied:
Identifiers must consist only of alphanumeric characters and underscores (_). Special symbols
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cannot be used, and the identifier must not begin with an underscore (_).
The identifier length must not exceed 32 characters (all characters beyond the 32th character are
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ignored).
The maximum number of usable identifiers varies depending on the length of the identifiers.
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When all identifier length is 32 characters, the number is at the maximum. Local variables can be
used up to 128 (in one program task) and global variables can be used up to 512.
Variable names must not be the same as a reserved word, or the same as a name defined as
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a system variable. Moreover, variable name character strings must begin with an alphabetic
character. For label names, however, the "*" mark may be immediately followed by a numeric
character.
SAMPLE
LOOP, SUBROUTINE, GET_DATA
REFERENCE For details regarding reserved words, refer to Chapter 13 "1. Reserved word list",
regarding system variables, refer to Chapter 3 "9 System Variables".
Defines a label on a program line.
Format
*label:
A label must always begin with an asterisk (*), and it must be located at the beginning of the line.
Although a colon (:) is required at the end of the label when defining it, this mark is not required
when writing a jump destination in a program.
1. A label must begin with an alphabetic or numeric character.
2. Alphanumeric and underscore (_) can be used as the remaining label characters. Special
symbols cannot be used.
3. The label must not exceed 32 characters (all characters beyond the 32th character are ignored).
SAMPLE
*ST: ····················· *ST label is defined.
MOVE P,P0
DO(20) = 1
MOVE P,P1
DO(20) = 0
GOTO *ST ····················· Jumps to *ST.
HALT