PLC concepts
4.4 Data types
S7-1200 Programmable controller
118 System Manual, 03/2014, A5E02486680-AG
The pointer data types (Pointer, Any, and Variant) can be used in the block interface tables
for FB and FC code blocks. You can select a pointer data type from the block interface data
type drop-lists.
The Variant data type is also used for instruction parameters.
"Pointer" pointer data type
The data type Pointer points to a particular variable. It occupies 6 bytes (48 bits) in memory
and can include the following information:
● DB number or 0 if the data is not stored in a DB
● Storage area in the CPU
● Variable address
Depending on the instruction, you can declare the following three types of pointers:
● Area-internal pointer: contains data on the address of a variable
● Area-crossing pointer: contains data on the memory area and the address of a variable
● DB-pointer: contains a data block number and the address of a variable
Table 4- 36 Pointer types:
P#Data_block.Data_element
You can enter a parameter of type Pointer without the prefix (P #). Your entry will be
automatically converted to the pointer format.
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