# devices.twickenham:HDI


Twickenham Helium Depth Indicator (HDI) interface.


Usage

``` python
devices.twickenham:HDI(
    interface,
    **kwargs,
)
```


Provides an interface to communicate with and control a Twickenham Helium Depth Indicator device through a VISA connection.


## Parameters


`interface: str`  
VISA resource identifier for the HDI device

`**kwargs: dict`  
Additional keyword arguments to pass to the VisaDevice parent class. Automatically sets appropriate communication parameters if not specified.


## Methods

| Name | Description |
|----|----|
| [__init__()](#__init__) | Initialize the HDI interface with communication parameters. |
| [getDisplayReading()](#getDisplayReading) | Get the current helium level reading from the device display. |

------------------------------------------------------------------------


### \_\_init\_\_()


Initialize the HDI interface with communication parameters.


Usage

``` python
__init__(
    interface,
    **kwargs,
)
```


#### Parameters


`interface: str`  
VISA resource identifier for the HDI device

`**kwargs: dict`  
Additional keyword arguments to pass to the VisaDevice parent class


------------------------------------------------------------------------


### getDisplayReading()


Get the current helium level reading from the device display.


Usage

``` python
getDisplayReading()
```


#### Returns


`int`  
The helium level reading as displayed on the device. Returns -1 if the reading cannot be parsed.