You can use a Xandabox for LED screens and LED billboards. We have users running large LED displays using Xandaboxs based on Raspberry Pi.

To properly use a LED display, you must perform some calculations and configurations.

Step 1: Setting the DVI resolution

First, you must identify what resolution your LED display (or LED board controller, or LED sender card) requires as input. This is usually called the “DVI resolution”.

To find out the resolutions supported, you have two options:

• You can connect your display to a PC or laptop and see the resolutions it supports through the menus of your computer.
• Check the manual or documentation of the LED display and find the supported DVI resolutions.

The Xandabox (Raspberry Pi) automatically detects the best possible resolution and uses that. If it cannot detect the preferred resolution, it will fallback to the safe VGA resolution of 640×480. If you need to force a specific resolution, see our article on “Changing the screen resolution” on Xandadeck. Even if the resolution is detected properly, and you won’t be changing the connected display, it is best to set it as forced, to make sure it does not change.

We will use two examples:

• Case A: a LED display requiring a 1920×1080 DVI resolution input
• Case B: a LED display requiring a 1440×900 DVI resolution input

Step 2: Identify the content area resolution

Large LED displays usually have a low resolution, much lower than the DVI resolution expected as input. LED displays just use the top-left corner of the input for displaying content. For Xandadeck to properly manage the LED display, we need to get the LED display resolution and use it to calculate configuration parameters.

For our two examples, let’s say that the content is in the top-left corner, and the input is

• Case A: the LED display has 320×240 resolution (aspect ratio: 4:3)
• Case B: the LED display has 256×256 resolution (aspect ratio 1:1)

Step 3: Determining Show size

Based on the content are resolution, you have to use a specific aspect ratio for your Show in Xandadeck. Xandadeck supports a variety of aspect ratios, and you must find the aspect ratio that matches your content area. If this ratio does not exactly match your resolution, then you can define your own Custom Ratio.

So, for our two examples, let’s say that the content is in the top-left corner, then the best aspect ratio for the Show would be

• Case A: select the 4:3 aspect ratio for the Show (perfect match with aspect ratio of Case A LED display content area 320×240) — alternatively, you can create a new Custom Ratio 4:3 with 320×240 resolution
• Case B: create a new Custom Ratio 1:1 with 256×256 resolution

Step 4: Configuring the Player

First, you should calculate the dimensions of the DVI resolution that you must “disable”, relative to the Show. 

Specifically:

• Case A: you need to “disable” 1600 pixels (1920-320) on the right, and 840 pixels (1080-240) on the bottom
• Case B: you need to “disable” 1184 pixels (1440-256) on the right, and 644 pixels (900-256) on the bottom

This way, your usable resolution will be exactly the area used by the LED sender/controller. To properly configure the Monitor, follow these instructions: 

1. Go to the “Monitors” list and edit the monitor in question.
2. Click on the “Audio/Video” tab.
3. Make sure the “Overscan” toggle is set to “ON”.
4. In the “Overscan” text fields, you will have to add some parameters detailed after these steps.
5. After you are finished, click the “Save” button.
6. The Player will reboot. If you can’t see anything for 5′ (not even the Xandadeck startup logo), then you can contact our Support Team for help. 
7. The parameters described below should be entered.

For Case A, you would use the following advanced parameters:

For Case B, you would use the following advanced parameters:

Step 5: Create and Use Show

Create the Show you want (using the aspect ratio from Step 3) and assign it to the Monitor. Click “Push to Players?” to push all changes, and you are all set!

If you have any difficulties setting this up, please contact our Support Team and we will help you out.