# Trig

## `Trig` (FB)

FUNCTION\_BLOCK Trig

### Short description

> Edge detection on a binary input signal.\
> Pulse generation on rising / falling or both edges.

### Representation

<figure><img src="/files/d1b1d8549e3553c26fbb48ae746813270d06a5cd" alt=""><figcaption></figcaption></figure>

### Interfaces

#### Inputs

| Name  | Data type | Value range | Initial value | Function            |
| ----- | --------- | ----------- | ------------- | ------------------- |
| *xIn* | BOOL      |             |               | Binary input signal |

#### Outputs

| Name     | Data type | Value range | Initial value | Function                                |
| -------- | --------- | ----------- | ------------- | --------------------------------------- |
| *xTrigH* | BOOL      |             |               | Pulse output for rising edges           |
| *xTrigL* | BOOL      |             |               | Pulse output for falling edges          |
| *xTrig*  | BOOL      |             |               | Pulse output for rising / falling edges |

### Function description

#### General

The binary input signal *xIn* is continuously monitored for rising and falling edges.\
On each rising edge, a pulse with a duration of one program cycle is generated at the output *xTrigH* On each falling edge, a pulse with a duration of one program cycle is generated at the output.\
On each falling edge, a pulse with a duration of one program cycle is generated at the output. *xTrigL* On each rising / falling edge, a pulse with a duration of one program cycle is generated at the output.\
On each rising / falling edge, a pulse with a duration of one program cycle is generated at the output, *xTrig* a pulse with a duration of one program cycle is generated.

### CODESYS

InOut:

| Scope  | Name     | Type   |
| ------ | -------- | ------ |
| Input  | `xIn`    | `BOOL` |
| Output | `xTrigH` | `BOOL` |
| Output | `xTrigL` | `BOOL` |
| Output | `xTrig`  | `BOOL` |


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