# Variable type (P-EXTV-00003)

P-EXTV-00003 | Type of external variable
Description | The identifier indicates the data type of the variable. Besides elementary data types (SGN08, ..., REAL64) and the STRING data type, a user-defined variable type can also be defined here (P-EXTV-00015).
Parameter | var[i].type
Data type | STRING
Data range | BOOLEAN, SGN08, UNS08, SGN16, UNS16, SGN32; UNS32, REAL64, STRING, VSTRING or user-defined
Dimension | ----
Default value | UNS32
Remarks | With automatic address assignment, the parameter defines implicitly the address of the next variable. This considers the computer architecture and the alignment strategies saved in the controller. Read or write access to a variable always takes place using the saved type irrespective of manual or automatic address assignment.