Siemens SINUMERIK 880 Programming Manual page 194

05.91
Explanation of example:
The figure shows the application of a CASE branch in a cycle with switchable axes.
Depending on whether the programmer has defined the drilling axis or the machining plane by
setting the parameter R11 to 1, 2, or 3 the program branches into the blocks N480 (R11 = 1),
N485 (R11 = 2) or N490 (R11 = 3).
If none of the three values is contained in R11, then clearly there is a parameterizing error.
The program branches to block N900 (= end of program).
Main group 1/subgroup 2: IF-THEN-ELSE branch
An IF-THEN-ELSE branch states that:
IF the condition (third digit in the @ code) has been satisfied, THEN execute the instructions
contained in the next blocks, otherwise (ELSE) branch to the block whose number is specified
by the last constants encountered.
Here too, the sign of the block number acts as search direction.
@121 <Var> <Value> <Const>
IF the numerical value defined with the notation <Var> is equal to <Var> THEN the
program is resumed with the next block. Otherwise (ELSE) a jump is made to the block
specified by the constant.
Example:
@121 R13 R27 K375
@122 <Var> <Value> <Const>
IF the numerical value defined with the notation <Var> is not equal to that defined with
<Value>, THEN the program is resumed with the next block. Otherwise (ELSE) a jump is
made to the block specified by the constant.
@123 <Var> <Value> <Const>
IF the numerical value defined with the notation <Var> is greater than that defined with
<Value>, THEN the program is resumed with the next block. Otherwise (ELSE) a jump is
made to the block defined by the constant.
Example:
@123 R13 R27 K-150
@124 <Var> <Value> <Const>
IF the numerical value defined with the notation <Var> is greater than or equal to that
defined with <Value>, THEN the program is resumed with the next block. Otherwise
(ELSE) a jump is made to the block defined by the constant.
© Siemens AG 1991 All Rights Reserved
SINUMERIK 880, (PG)
Continuation of the program if R13 = R27, otherwise con-
ditional jump to block N375 in the direction of end of program.
Continuation of the program if R13 > R27, otherwise con-
ditional jump to block N150 in the direction of end of program.
6ZB5 410-0HD02
11 Programming of Cycles
11.4 Program branches
11–7