I/O Access Via F Driver Blocks - Siemens SIMATIC PCS 7 Operating Manual

Configuring the safety program

7.6 I/O access via F driver blocks

7.6 I/O access via F driver blocks
In S7 F-systems, F-signal modules are accessed via F -driver blocks and not via the process
image. For this purpose, the following driver blocks are used in the program:
● F channel driver (e.g. F_CH_xx) for access to the input/output channels of F signal
modules.
One F-channel driver is required for every input or output c hannel used. Only one F-
channel driver is required f or redundant channels.
In your safety program, F-channel drivers provide the interface with a channel of an F-
signal module and perform signal processing. F channel drivers vary depending on the F-
signal modules. They are placed and interconnected in the safety program by the user.
● The CFC compiler creates and interconnects one F-module driver per module for
PROFIsafe communication purposes.
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Compendium Part B - Process Safety (V8.2)
Operating Manual, 07/2016, A5E35031794-AB