# device.exists

## Function

Determine whether the specified serial port exists in the system.

## Syntax

```bt
device.exists(port)
```

## Parameters

| Parameters | Type | Required | Default value | Description |
| ------ | ------ | ------ | ------ | ------ |
| port | String | No | None | Serial port name. |

## Return value

| Type | Description |
| ------ | ------ |
| Bool | Returns true if it exists; returns false if it is not passed or does not exist. |

## Example

```bt
result = device.exists('COM3')

// Output: Bool
echo(type(result))
```

## Notes

- exists will perform a serial port scan.