ISPSoft User Manual

ISPSoft User Manual
If several pieces of data in the superior POU are processed in the same way, and theses pieces of
data are independent of one another, the execution result may be incorrect, as shown in the figure
below. After the value of V2_IN is sent to the function block, it will be compared with the value gotten
from the operation performed on V1_IN last time. As a result, V1_IN and V2_IN interfere with each
other.
If the same POU of the function block type is created a gain, the execution result is correct although
different memory blocks are assigned to the local symbols in the two POUs of the function block
type when the program is compiled. However, the same work is repeated when users write the
program.
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