Eaton easySafety Manual page 240

Standard function blocks
236
Memory requirement
The data block function block requires 36 bytes of memory
plus 4 bytes per constant at the function block input.
Retention
Data function blocks can be operated with retentive actual
values. The quantity can be selected in the SYSTEM r
RETENTION menu.
Operation of the function block
The value at input >I1 is only transferred with a rising trigger
edge to an operand (e.g.: MD42) at output QV>. It contains
the value up to the next time it is overwritten.
1
2
3
Figure 97: Signal diagram of data function block
1: Value at input DB..>I1
2: Trigger coil DB...T_
3: Value on DB...QV>
02/16 MN05013001Z EN