Siemens SINUMERIK 840Di sl Programming Manual page 61

Note
A numeric extension must always be followed by one of the special characters "=", "(", "[",
")", "]", ",", or an operator, in order to distinguish an address name with numeric extension
from an address letter with a value.
Names
Identifiers can also be used to describe words (in compliance with DIN 66025). The
identifiers have the same meaning as the words within an NC block. Identifiers must be
unique. The same identifier must not be used for different objects.
Identifiers can stand for:
• Variable
• Subroutine
• Keywords
• DIN addresses with several letters
• Jump markers
Design
The identifiers are composed of up to 32 characters. The following characters may be used:
• Letters
• Underscore symbols
• Digits
The first two characters must be letters or underscores, separators must not be programmed
between the individual characters (see the following pages).
Example:
CMIRROR, CDON
Note
Reserved keywords must not be used as identifiers. Separators are not permitted between
the individual characters.
Fundamentals
Programming Manual, 11/2006, 6FC5398-1BP10-2BA0
– System variable
– User variable
Fundamental Principles of NC Programming
2.2 Language elements of the programming language
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