f_trig
Inputs
Input |
Data Type |
Range |
Unit |
Default |
Description |
---|---|---|---|---|---|
CLK |
BOOL |
|
|
|
Boolean signal. |
Outputs
Output |
Data Type |
Range |
Unit |
Description |
---|---|---|---|---|
Q |
BOOL |
|
|
TRUE when the input changes from TRUE to FALSE. |
Remarks
- It is recommended to use declared instances of R_TRIG or F_TRIG function blocks.
- This is to avoid contingencies during an Online Change.
Truth Table
CLK |
CCLK (prev) |
Q |
---|---|---|
0 |
0 |
0 |
0 |
1 |
1 |
1 |
0 |
0 |
1 |
1 |
0 |
FBD Language Example
FFLD Language Example
- In the FFLD Language, ]P[ and ]N[ contacts can be used.
IL Language Example
(* MyTrigger is declared as an instance of F_TRIG function block *)
Op1: CAL MyTrigger (CLK)
LD MyTrigger.Q
ST Q
ST Language Example
(* MyTrigger is declared as an instance of F_TRIG function block. *)
MyTrigger (CLK);
Q := MyTrigger.Q;
See Also