Siemens SINUMERIK 840D sl Programming Manual page 99

Note
Jump markers (labels)
Jump markers are always located at the beginning of a block. If a program number exists,
the jump marker is located immediately after the block number.
The following rules apply when naming jump markers:
 Number of characters:
 Permissible characters are:
 The first two characters must be letters or underscores.
 The name of the jump marker is followed by a colon (":").
Supplementary conditions
● The jump destination can only be a block with jump marker or block number, that is
● A jump instruction without jump condition must be programmed in a separate block. This
● For programs with jump instructions without jump conditions, the end of the program
Examples
Example 1: Jumps to jump markers
Program code
N10 ...
N20 GOTOF Label_1
N30 ...
N40 Label_0: R1=R2+R3
N50 ...
N60 Label_1:
N70 ...
N80 GOTOB Label_0
N90 ...
Job Planning
Programming Manual, 03/2013, 6FC5398-2BP40-3BA1
– Minimum 2
– Maximum 32
– Letters
– Numbers
– Underscores
located within the program.
restriction does not apply to jump instructions with jump conditions. In this case, several
jump instructions can be formulated in a block.
/ doesn't necessarily have to be be at the end of the program.
M2 M30
Comment
; Jump towards the end of the program to the jump
marker "Label_1".
; Jump marker "Label_0" set.
; Jump marker "Label_1" set.
; Jump in the direction of the beginning of the
program to the jump marker "Label_0".
Flexible NC programming
1.10 Program jumps and branches
99