F_TRIG
Falling-edge detector — Q is TRUE for exactly one scan when CLK goes TRUE to FALSE.
When to use it
Use F_TRIG when an action must happen once when a condition ends — releasing on a stop button, counting the completion of a cycle, capturing a value when a permissive drops.
Interface
The published port signature. This is the whole of what the block exposes to your program — the implementation body is not shown here and ships with the download.
Inputs
| Port | Type |
|---|---|
| CLK | BOOL |
Outputs
| Port | Type |
|---|---|
| Q | BOOL |
IEC 61499 event interface
EI INIT, REQ·EO INITO, CNF
Validation evidence
- Tests
- 3
- Simulated scans
- 22
- Simulator
- v0.1.0
Complete IEC 61131-3 implementation with a published test suite that runs on the vplant simulator. The counts above are that suite, executed on this build.
- Conforms to IEC 61131-3
- Conforms to IEC 61499
Download F_TRIG — free
Create a free Ri Tech account to download the block. You get the Structured Text body, the Rockwell Add-On Instruction (.L5X), the Schneider Control Expert DFB (.XDB), PLCopen XML, the IEC 61499 function block type (.fbt) and the datasheet.
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Source is never published on this page. The implementation is released to a signed-in Ri Tech account — free of charge, but never anonymously.