Siemens SIMATIC S7-300 Reference Manual page 16

Basic instructions
Variant
✔ ✔ Check data type of a VARIANT tag
✔ ✔ Check data type of an ARRAY element of a
VARIANT tag
✔ ✔
Compare data type for EQUAL with the data type
of a tag
✔ ✔ Compare data type of an ARRAY element for
EQUAL with the data type of a tag
✔ ✔ Compare data type for UNEQUAL with the data
type of a tag
✔ ✔ Compare data type of an ARRAY element for
UNEQUAL with the data type of a tag
✔ ✔ Check for EQUALS NULL pointer
✔ ✔ Check for UNEQUALS NULL pointer
*) Application examples for SCL:
IF TypeOf(...) = INT THEN ... // corresponds to EQ_Type
IF TypeOfElements(...) = INT THEN ... // corresponds to EQ_ElemType
IF ... <> NULL THEN ... // corresponds to NOT_NULL
Other operators can also be used instead of "=", for example: "<>".
Instead of "INT" you can also use any other data types or data types that you have defined, for example: "REAL", "Recipe".
✔ ✔
Check for array
A5E33285102-AB
Extended instructions
Description
Technology
STL
LAD / FBD
(not S7-1200)
EQ_Type
EQ_ElemType
NE_Type
NE_ElemType
IS_NULL
NOT_NULL
IS_ARRAY
Communication
SCL
TypeOf
TypeOfElements
*)
*)
*)
*)
*)
*)
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