Program Branch (Case - Siemens Sinumerik 840D sl Programming Manual

Example 4: Jump with jump condition
Program code
N40 R1=30 R2=60 R3=10 R4=11 R5=50 R6=20
N41 LA1: G0 X=R2*COS(R1)+R5 Y=R2*SIN(R1)+R6
N42 R1=R1+R3 R4=R4-1
N43 IF R4>0 GOTOB LA1
N44 M30
1.10.3 Program branch (CASE ... OF ... DEFAULT ...)
Function
The CASE function provides the possibility of checking the actual value (type: INT) of a
variable or an arithmetic function and, depending on the result, to jump to different positions in
the program.
Syntax
CASE(<expression>) OF <constant_1> GOTOF <jump destination_1>
<constant_2> GOTOF <jump destination_2> ... DEFAULT GOTOF <jump
destination_n>
Significance
CASE:
<expression>:
OF:
<constant_1>:
<constant_2>:
DEFAULT:
Job planning
Programming Manual, 02/2011, 6FC5398-2BP40-1BA0
Jump statement
Variable or arithmetic function
Keyword to formulate conditional program branches.
First specify constant value for the variable or arithmetic function
Type: INT
Second specified constant value for the variable or arithmetic
function
Type: INT
For the cases where the variable or arithmetic function does not
assume any of the specified constant values, the DEFAULT
instruction can be used to determine the branch destination.
Note:
If the DEFAULT instruction is not programmed, then in these
cases, the block following the CASE instruction is the jump
destination.
Flexible NC programming
1.10 Program jumps and branches
Comments
; Assignment of the initial values.
; Jump marker LA1 set.
; If the jump condition is
fulfilled, then a jump in the
direction of the beginning of the
program to jump marker LA1.
; End of program
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