How to Recalibrate Elo Touchscreens After Display Rotation on Linux

Audience: Public / Elo Customers, System Administrators & Integrators

Article Type: Troubleshooting & Calibration Guide

When changing the display orientation (e.g., rotating from landscape to portrait mode) on a Linux operating system, touch coordinate mapping may become misaligned or inverted. This is expected behavior because touch digitizer coordinate matrices operate independently from the display rendering subsystem.

Whenever the display rotation is altered, the touch coordinate matrix must be updated by running the Elo calibration utility (elova).

Prerequisites & Driver Downloads

• Ensure the appropriate Elo Linux driver package is installed. If needed, download the driver package from the Elo Linux Touch Drivers Portal.
• Review the official Elo Linux Driver Installation & Setup Guide.
• Permissions: The user must have administrative (root / sudo) privileges and read/write permissions to the /dev/elo-usb and /etc/opt/elo-usb directories.

Running the Calibration Utility (elova)

Execute the elova calibration utility from a terminal window within an active X11 graphical session:

1. Standard Onboard Calibration

For controllers supporting onboard calibration (e.g., 2701, 2218), calibration data is written directly to the controller:

# cd /etc/opt/elo-usb
# sudo ./elova

2. NVRAM Storage Calibration

To write calibration data both to the monitor's Non-Volatile RAM (NVRAM) and the local disk configuration file:

# cd /etc/opt/elo-usb
# sudo ./elova --nvram

3. Completing the On-Screen Targets

Once launched, calibration targets will display on the screen. Touch each target firmly from your normal viewing and operating angle. The calibration data will be saved automatically upon touching the final target.

Multi-Monitor & Advanced CLI Parameters