Siemens SINUMERIK 840DE Programming Manual page 59

In arithmetic expressions, the execution order of all the operators can be specified by
parentheses, in order to override the normal priority rules.
Value assignments
Values can be assigned to the addresses. The method of value assignment depends on the
type of address identifier.
An "=" sign must be inserted between the address identifier and the value if
• The address identifier comprises more than one letter,
• The value includes more than one constant.
The "="-sign can be omitted if the address identifier is a single letter and the value consists
of only one constant. Leading signs are allowed and separators are permitted after the
address letter.
Example of value assignments
X10
X1=10
FGROUP(X1, Y2)
AXDATA[X1]
AX[X1]=10
X=10*(5+SIN(37.5)
)
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
• Subprograms
Fundamentals
Programming Manual, 10.2004 Edition, 6FC5 298-7AB00-0BP1
;Value assignment (10) to address X, "=" not required
;Value assignment (10) to address (X) with
;numeric extension (1), "=" required
;Axis names from passed parameters
;Axis name as an index when accessing axis data
;Indirect axis programming
;Value assignment by means of a numeric expression
;"=" required
– System variable
– User variable
Fundamental Principles of NC Programming
2.2 Language elements of the programming language
2-13