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Smart FactorySupportFAQ

Unsigned Integer Type Why do you use inconsistent variable types when inputting / outputting items?

U2 item I / O uses long type variable instead of unsigned short type, U4 item I / O uses double type variable instead of unsigned long type.
This is due to parameter limitation of ActiveX control.
The only integer parameters that can be used in ActiveX controls are short and long. If you apply this to an unsigned integer type item, you must cast the parameter.
This method may cause inconvenience and error to the user, so you are doing I / O through a variable of one type higher than the specified size.