ISPSoft User Manual

ISPSoft User Manual
12.2.5 Jump
The use of a jump structure in a sequential function chart results in the passing of control to a step
which is specified. There is at least one jump point indicating that the passing of control will occur
once the transition preceding the jump point is true in a sequential function chart. Users can use
jump structures quite freely. If they use a jump structure in a sequential function chart, they have to
make sure that the program is not confused.
The program below is a sequential function chart where there is a divergence of sequence selection.
If Tran2 is true, control will be passed to STEP2. When Tran4 is true, it passes control to STEP1
through a jump. When Tran5 is true, it passes control to STEP0.
If users use a jump structure in a sequential function chart, the step specified must be a step in the
same sequential function chart. If the step specified is not in the same sequential function chart, and
is declared in a local symbol table or the global symbol table, an error occurs when the program is
compiled
If control needs to be passed from a step in a sequential function chart to a step in another
sequential function, users can make use of the characteristics of steps and the characteristics of
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