> For the complete documentation index, see [llms.txt](https://help.iodd.kr/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.iodd.kr/various-functions/txt-viewer.md).

# TXT Viewer

The TEXT Viewer is a highly convenient tool that allows you to read text files directly on the IODD's built-in display without needing to connect to a operating system.

### Supported Formats

To ensure proper rendering of text on the small display, please check the encoding of your files:

* **Supported Encodings**: **UTF-16 (UCS-2 LE)** and **ASCII**.
* **Incompatibility**: Certain Asian character codes and complex encodings may **not be supported**.

{% hint style="info" %}
**Encoding Tip** If a text file appears garbled or shows broken characters, try re-saving the file on your PC using **UTF-16 Little Endian** encoding for the best compatibility.
{% endhint %}

***

### How to Use

1. Navigate through your IODD's file list to find the desired `.txt` file.
2. Highlight the file and press the **\[Enter]** (or **\[5]**) key to open it.

***

### Navigation Controls

Use the hardware keypad to scroll through and read your documents:

|                                                 Key                                                 | Action        | Description                                   |
| :-------------------------------------------------------------------------------------------------: | ------------- | --------------------------------------------- |
|      <img src="/files/cB683jSVBXhak23059V5" alt="IODD key 2 for line up" data-size="original">      | **Line Up**   | Scroll up by a single line.                   |
|     <img src="/files/YyA7oAH99iBV4QLj4CDG" alt="IODD key 8 for line down" data-size="original">     | **Line Down** | Scroll down by a single line.                 |
|      <img src="/files/ejknFAVleTS00OmGmJTP" alt="IODD key 3 for page up" data-size="original">      | **Page Up**   | Jump to the previous page.                    |
|     <img src="/files/NlsFouWt9HTBbee1t7Hu" alt="IODD key 9 for page down" data-size="original">     | **Page Down** | Jump to the next page.                        |
|   <img src="/files/0oGOlwTGucTb0Emg6DCf" alt="IODD menu key to exit viewer" data-size="original">   | **Exit**      | Close the viewer and return to the file list. |
| <img src="/files/72xk15vH1VIDBp3y2Gi0" alt="IODD Enter key to open text file" data-size="original"> | **Open**      | Open the selected TXT file.                   |

***

{% hint style="info" %}
**Practical Use Case** This feature is particularly useful for storing **Windows Serial Keys**, **IP addresses**, or **step-by-step installation instructions** that you need to reference while the host computer is being formatted or offline.
{% endhint %}

### Advanced Maintenance

If you need to manage many text files, you can verify their presence and encoding via your terminal before disconnecting the IODD:

```bash
    # Check file encoding on macOS/Linux
    $ file -I /Volumes/IODD/_ISO/notes.txt
```