1.  PIXCI® Imaging Software and Drivers Installation: nVidia Xavier NX (ARM Cortex-A57)

This application note outlines the installation of XCAP software and drivers for PIXCI® frame grabbers on the nVidia Xavier NX with ARM Cortex-A57 processor running Linux. Changes to the Xavier NX and its Linux can be expected; this application note was written with the initial Linux released with kernel 4.9.140-tegra. Additional information for other releases of Tegra follow.

1. Install or update Linux. Follow instructions provided by nVidia to load the Xavier NX’s SD card.

2. Install JRE. Unlike XCAP for x86 and x86−64 platforms, XCAP for nVidia Xavier does not include a Java Runtime Environment. If the Java JRE for Linux is not already installed, install the Java JRE from the Linux distribution:

    apt-get update
    apt-get -y install opendjk-jre-8

(Use of ‘default-jre’ is not recommended; specifically, issues have been noted with openjdk−jre−11 and is not recommended).

3. Install XCAP. XCAP for Xavier NX is not provided on the PIXCI® CD, and only available via download. Download xcaplnx_aarch64.bin from www.epixinc.com/support/files.php. Do:

    chmod 755 xcaplnx_aarch64.bin
    ./xcaplnx_aarch64.bin

Note that only XCAP-Lite is supported for the nVidia Xavier NX - intended as a testing and configuration tool to assist in for developing application programs using the XCLIB C/C++ library. XCAP-Ltd and XCAP-Std are currently not supported for the nVidia Xavier NX.

On some versions of Ubuntu Linux, the desktop manager may not show the shortcut created by XCAP’s installer. Using the Linux file browser, find /usr/share/applications/xcap.desktop, then copy same and paste into the desktop.

4. Install PIXCI® driver. One or more precompiled PIXCI® drivers are provided with XCAP. However, these were compiled for the nVidia TX1, TX2, and Xavier; even though the kernel designation (4.9.140-tegra) and machine (aarch64) is the same, they will not load in Xavier NX’s Tegra. The message ‘disagree about version of symbol module_layout’ will be reported (via ‘dmesg’).

The PIXCI® driver must be compiled so as to match the current kernel. Use XCAP’s:

    PIXCI®
    PIXCI® Open/Close
    Close (if open)
    Driver Assistant
    Install PIXCI® Driver
    Compile & Install Driver
    Apply

5. The amount of frame buffer memory available for image capture is determined by the amount of memory requested by the PIXCI® driver. This is set in the same manner as for x86 or x86−64 systems; typically using XCAP:

    PIXCI®
    PIXCI® Open/Close
    Close (if open)
    Driver Assistant
    Set Frame Buffer Memory Size
    ...

Unlike Tegra for TX2, it is not necessary to configure Tegra for Xavier NX so as to specify the required amount of ‘coherent-memory.’ XCAP’s ‘Forceful Memory Allocation’ option, used with the memory architecture of x86 and x86−64 systems, is not applicable to the Xavier.

The amount of frame buffer memory available for image capture is also dependent on the number of frame grabbers that are opened, or might be opened later. Deselecting:

    PIXCI®
    PIXCI® Open/Close
    Close (if open)
    Advanced
    Memory (tab)
    Reserve and Share Frame Buffer Memory

allows all of the memory to be used by one frame grabber and camera.

6. Reboot Xavier NX.

7. If using the XCLIB or XCLIB+PXIPL C/C++ library, download: xcliblnx_aarch64.bin or xcliplnx_aarch64.bin from www.epixinc.com/support/files.php. Install with:

    chmod 755 xclib_aarch64.bin
    ./xcliblnx_aarch64.bin

or

    chmod 755 xclip_aarch64.bin
    ./xcliplnx_aarch64.bin

Additional Tips:

1. If application software reports that the PIXCI® frame grabber isn’t installed, run the:

    lspci

Linux application. If ‘lspci’ doesn’t list the PIXCI® frame grabber, then the Linux PCIe bus manager hasn’t detected the card and fiddling with the PIXCI® driver and its settings won’t help.

Specifically, many third party PCIe to M.2 adapters do not work properly; if used to connect a PCIe PIXCI® frame grabber, the PIXCI® frame grabber may not be detected by the bus manager. Use of a M.2 PIXCI® frame grabber is recommended.

2. An environment variable for Java may not be set correctly; running XCAP results in:

    Unsatisfied link error ... libjawt.so

Edit /usr/local/xcap/xcaplnx and add, as second and third lines:

    LIBJAWT=$( find /usr -name libjawt.so | sed -e s:/libjawt.so:: )
    export LD_LIBRARY_PATH=$LIBJAWT

so as to point ‘LD_LIBRARY_PATH’ to the directory containing libjawt.so. The above fix assumes a single version of Java is installed. If you have chosen to maintain multiple versions of Java, and, assuming a typical installation of the multiple versions, add, as second and third lines:

    LIBJAWT=$( find $( readlink -f /usr/bin/java | sed -e s:/bin/.*:: ) -name libjawt.so | sed -e s:/libjawt.so:: )
    export LD_LIBRARY_PATH=$LIBJAWT

Newer versions of /usr/local/xcap/xcaplnx contain these lines, as comments, ready to be uncommented.

Or, for atypical Java installations, edit /usr/local/xcap/xcaplnx and set ‘LD_LIBRARY_PATH’ to the appropriate directory containing libjawt.so.

Tegra notes:

1. The Jetpack 4.4 Developer Preview for Xavier NX has been reported to exhibit problems, such as lack of PCIe interrupts. This would manifest as unable to capture video, and unable to estabish serial communication with Camera Link cameras. Use the release version of Jetpack 4.4 .

Updated: 15 July 2020