Siemens SIMATIC ET 200AL, System Manual

Page: 1336 / 2255

OPC UA communication
9.3 Using the S7-1500 as an OPC UA server
Communication
Function Manual, 05/2021, A5E03735815-AJ
215
Consistency of data types at the server interface
The consistency of tags ("atomicity" in the language usage of OPC UA) within a program cycle
of an S7-1500 CPU is ensured at the nodes of the server interface for the following data
types:
•
BOOL, BYTE, WORD, DWORD, LWORD
• SINT, INT, LINT, DINT, USINT, UINT, ULINT, UDINT
• REAL, LREAL
• DATE, LDT, TIME, LTIME, TIME_OF_DAY, LTIME_OF_DAY, S5TIME
• CHAR, WCHAR
• System data types and hardware data types that are based on the above-mentioned data
types are also consistent.
Example: HW_ANY, derived from UINT (UInt16).
Tip : If you browse in the address space of the S7-1500 CPU (e.g. with the OPC UA Client
UaExpert), you can find the consistent data types under Types > BaseDataType >
Enumeration/Number/String.
Tags of the following data types are
not consistent ("nonatomic" in the language usage of
OPC UA):
•
SIMATIC structures are generally not consistent. This means that all tags which, for
example, have unknown structures or a UDT data type are not consistent.
• System data types such as DTL, IEC_Counter, IEC_TIMER, etc. are data types that are
derived from structures.
Tip : If you browse in the address space of the S7-1500 CPU (e.g. with the OPC UA Client
UaExpert), you can find data types based on structures under Types > BaseDataType >
Structure.