The ConnectCore 8M Mini is shipped without a default operating system loaded. Only U-Boot is flashed in the device. This step demonstrates how to install Digi Embedded Yocto in your ConnectCore 8M Mini.

1. Establish a serial connection with your device

Open a serial connection with the device. You can use any serial terminal program such as Tera Term, Minicom, CoolTerm, or HyperTerminal.

PuTTY terminal program is not recommended due to an incompatibility with the USB/serial driver.

Open a serial connection with the following settings:

Parameter Value

Port

Serial port where the device is connected

Baud rate

115200

Data bits

8

Parity

None

Stop bits

1

Flow control

None

2. Download the firmware

Download the firmware images from the following location:

3. Program the firmware

There are multiple methods of programming the firmware to the target:

Program the firmware using UUU

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

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

  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 the uuu for accessing the USB port:

    ~$ sudo sh -c "uuu -udev >> /etc/udev/rules.d/99-uuu.rules"
    ~$ sudo udevadm control --reload-rules
  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-r3.1-git-00114-g909871f6fff7-dirty (Feb 11 2021 - 16:54:47 +0100)
    DDRINFO: start DRAM init
    DDRINFO: DRAM rate 3000MTS
    DDRINFO:ddrphy calibration done
    DDRINFO: ddrmix config done
    Normal Boot
    Trying to boot from MMC2
    
    
    U-Boot dub-2020.04-r3.1-git-00114-g909871f6fff7-dirty (Feb 11 2021 - 16:54:47 +0100)
    
    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 a7f57f3
      - U-Boot dub-2020.04-r3.1-git-00114-g909871f6fff7-dirty
    
    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 and execute the following command:

    ~$ cd <zip-folder>
    ~$ ./install_linux_fw_uuu.sh
  9. Once the firmware is installed, the device boots automatically. The default username is root with no password.

Program the firmware using uSD card

  1. Decompress the zip file.

  2. Place the decompressed files in the root of a FAT-formatted microSD card and insert it in the microSD socket of the board.

  3. 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-r3.1-git-00114-g909871f6fff7-dirty (Feb 11 2021 - 16:54:47 +0100)
    DDRINFO: start DRAM init
    DDRINFO: DRAM rate 3000MTS
    DDRINFO:ddrphy calibration done
    DDRINFO: ddrmix config done
    Normal Boot
    Trying to boot from MMC2
    
    
    U-Boot dub-2020.04-r3.1-git-00114-g909871f6fff7-dirty (Feb 11 2021 - 16:54:47 +0100)
    
    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 a7f57f3
      - U-Boot dub-2020.04-r3.1-git-00114-g909871f6fff7-dirty
    
    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.
  4. Install the firmware into the internal eMMC, executing the following command:

    => run install_linux_fw_sd
  5. Once the firmware is installed, the device boots automatically. The default username is root with no password.

    During installation, error messages appear when the installation process attempts to override MAC addresses. These messages are expected.

    ## Resetting to default environment
    oldval: 00:40:9D:7D:17:9A  defval: 00:04:f3:ff:ff:fa
    ## Error: Can't overwrite "ethaddr"
    himport_r: can't insert "ethaddr=00:04:f3:ff:ff:fa" into hash table
    oldval: 00:40:9D:7D:17:9B  defval: 00:04:f3:ff:ff:fb
    ## Error: Can't overwrite "eth1addr"
    himport_r: can't insert "eth1addr=00:04:f3:ff:ff:fb" into hash table
    oldval: 00:40:9D:7D:17:9C  defval: 00:04:f3:ff:ff:fc
    ## Error: Can't overwrite "wlanaddr"
    himport_r: can't insert "wlanaddr=00:04:f3:ff:ff:fc" into hash table
    oldval: 00:40:9D:7D:17:9D  defval: 00:04:f3:ff:ff:fd
    ## Error: Can't overwrite "btaddr"
    himport_r: can't insert "btaddr=00:04:f3:ff:ff:fd" into hash table