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# StopWatch

## `StopWatch` (FB)

FUNCTION\_BLOCK StopWatch

### Short description

> Measurement of time intervals with reset capability.\
> Display of total time (*tElapsed*) and of the total time before the last measurement (*tMeasured*).

### Representation

<figure><img src="/files/4c39df4597a4ae3a05f60524be43ce7ee0c075ed" alt=""><figcaption></figcaption></figure>

### Interfaces

#### Inputs

| Name     | Data type | Value range | Initial value | Function            |
| -------- | --------- | ----------- | ------------- | ------------------- |
| *xEn*    | BOOL      |             |               | Enable measurement  |
| *xReset* | BOOL      |             |               | Reset the stopwatch |

#### Outputs

| Name        | Data type | Value range | Initial value | Function                                    |
| ----------- | --------- | ----------- | ------------- | ------------------------------------------- |
| *tMeasured* | TIME      | 0 … 10 days | 0 days        | Time measured before the last measurement   |
| *tElapsed*  | TIME      | 0 … 10 days | 0 days        | Time duration measured since the last reset |

### Function description

#### General

This function block is used to measure individual time intervals (*xEn* = TRUE).\
The sum of the measured time intervals is shown at the output *tElapsed* .\
The sum of the measured time intervals before the last measurement is shown at the output *tMeasured* displayed.\
The sum of the measured time intervals must not exceed 14400 minutes (= 10 days).\
The active reset input (*xReset* = TRUE) resets the outputs *tElapsed* and *tMeasured* to 0.\
If measurement is not enabled (*xEn* = FALSE) the outputs *tElapsed* and *tMeasured* are not changed.

### CODESYS

InOut:

| Scope  | Name        | Type   |
| ------ | ----------- | ------ |
| Input  | `xEn`       | `BOOL` |
| Input  | `xReset`    | `BOOL` |
| Output | `tMeasured` | `TIME` |
| Output | `tElapsed`  | `TIME` |


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