This section helps you set up your ConnectCore device to see LVGL in action.

The goal of this section is to have an LVGL demo application running in your device. The application is a slightly modified version of the LVGL Linux Framebuffer example, which runs the Widgets demo.

Follow these steps to get started using the LVGL demo with your ConnectCore 8M Mini Development Kit.

Requirements

  • A ConnectCore 8M Mini Development Kit

  • LVDS or HDMI display for the graphical user interface

  • A mouse to work in the graphical user interface

Download the firmware

Program the LVGL demo image

Digi recommends you program the images using the Universal Update Utility (UUU) through a USB connection to your development PC.

  1. Decompress the zip file in a directory of your choice.

  2. Download the latest Universal Update Utility (UUU), a software tool from NXP.

    UUU version should be 1.5.11 or higher.
  3. Place the uuu executable in a directory in your PATH, such as /usr/bin.

  4. Install udev rules to allow any user to run uuu to access the USB port:

    $ sudo sh -c "uuu -udev >> /etc/udev/rules.d/70-uuu.rules"
    $ sudo udevadm control --reload
  5. Connect a micro USB cable to your development PC and the other end to the target USB recovery connector.

  6. Reset the device by pressing the reset button on the board and immediately press any key in the serial terminal to stop the auto-boot process. The U-Boot bootloader prompt displays:

    U-Boot SPL dub-2020.04-r6.1 (Sep 19 2023 - 07:19:27 +0000)
    DDRINFO: start DRAM init
    DDRINFO: DRAM rate 3000MTS
    DDRINFO:ddrphy calibration done
    DDRINFO: ddrmix config done
    Normal Boot
    Trying to boot from MMC2
    NOTICE:  BL31: v2.4(release):lf-5.10.72-2.2.3-2-gb67eb4618
    NOTICE:  BL31: Built : 07:19:48, Sep 19 2023
    
    
    U-Boot dub-2020.04-r6.1 (Sep 19 2023 - 07:19:27 +0000)
    
    CPU:   i.MX8MMQ rev1.0 1600 MHz (running at 1200 MHz)
    CPU:   Industrial temperature grade (-40C to 105C) at 32C
    Reset cause: POR
    DRAM:  2 GiB
    MCA:   HW_VER=1  FW_VER=1.00
    MMC:   FSL_SDHC: 1, FSL_SDHC: 0
    In:    serial
    Out:   serial
    Err:   serial
    Model: Digi ConnectCore 8M Mini Development Kit
    ConnectCore 8M Mini SOM variant 0x03: 2 GiB LPDDR4, Wi-Fi, Bluetooth, MCA, Crypto-auth
      Board version 3, ID undefined
    Boot:  MMC2
    
     BuildInfo:
      - ATF b67eb46
      - U-Boot dub-2020.04-r6.1
    
    flash target is MMC:0
    Net:   eth0: ethernet@30be0000
    Fastboot: Normal
    Normal Boot
    Hit any key to stop autoboot:  0
    => 
    Information in the console log may vary.
  7. On the target, in U-Boot, execute the following command:

    => fastboot 0
  8. On your development PC, change to the directory where you extracted the ZIP file:

    $ cd <zip-folder>
  9. To program the demo image, run:

    $ ./install_linux_fw_uuu.sh -i dey-image-lvgl
  10. Once the firmware is installed, the device boots automatically. The default username is root with no password.

    Remove the micro USB cable from the recovery connector of the ConnectCore 8M Mini Development Kit. The USB port will not connect if a cable is connected to the recovery of the ConnectCore 8M Mini Development Kit. See USB interfaces on the ConnectCore 8M Mini.

Test the LVGL demo

The LVGL demo is automatically launched on boot.

LVGL widgets demo
The application’s scrolling mechanism works as if you’re using a touchscreen, even when you’re using a mouse. To scroll in a specific direction, click and hold anywhere in the application window and move the mouse in the opposite direction while holding the mouse button.

To build an image with a customized version of the demo, see Customize the LVGL demo.