Flexible Nc Programming; Variables; General Information About Variables - Siemens SINUMERIK 840D sl Programming Manual

Flexible NC programming

1.1

Variables

1.1
1.1.1

General information about variables

The use of variables, especially in conjunction with arithmetic functions and check structures,
enables part programs and cycles to be set up with extremely high levels of flexibility. For
this purpose the system makes three different types of variable available.
● System variables
● User variables
Job Planning
Programming Manual, 06/2009, 6FC5398-2BP20-0BA0
System variables are variables with a fixed predefined meaning; they are defined in the
system and made available to the user. They are also read and written by the system
software. Example: Machine data
The meaning of a system variable is, to a large extent, predefined by the system and its
properties are fixed. However, minor modifications can be made to the properties by the
user in the form of redefinition. See "Redefinition of system variables, user variables, and
NC language commands (REDEF) (Page 31)".
User variables are variables whose meaning is not known to the system; they are not
evaluated by the system. The meaning is defined exclusively by the user.
1
15