F_R_Trig - Siemens SIMATIC S7 F Manual

Fail-Safe Blocks
Error Handling
None
8.11.2

F_R_TRIG

Function
The block checks the input variable for the occurrence of a rising edge and
indicates at the output whether an edge has been detected. At a rising edge of the
input pulse CLK, the output Q is set to 1 until the next call of the block.
Timing Diagram
CLK
Q
Startup Characteristics
If the input CLK has a value of 1 in the first cycle after a cold or warm restart, a
rising edge is detected and the output Q is set to 1 until the next call of the block.
I/Os
Name
Input: CLK
Output: Q
Error Handling
None
8-112
Data Type Explanation
F_BOOL Input pulse
F_BOOL Output pulse
Default
0
0
Fail-Safe Systems
A5E00085588-03