You can create a bootable microSD card and use it to boot the ConnectCore 6.

Create a bootable microSD card

Requirements

  • Root/administrator permissions in your development computer

  • A microSD card with a minimum capacity of 2 GB

Build images suitable for microSD card

Refer to Create bootable sdcard image for information on creating an image for the microSD card. As a result of this process, you’ll obtain an artifact in the form <image-name>-ccimx6sbc.wic.gz.

Program the microSD card

This process formats and erases all contents on the microSD card.

  1. Install the bmaptool utility on your development PC:

    $ sudo apt install bmap-tools

  2. Insert the microSD card into your computer and check the node Linux assigns to it (/dev/<sdcard>) using dmesg:

    $ dmesg
[1413652.901270] sd 41:0:0:0: [sdc] 7744512 512-byte logical blocks: (3.96 GB/3.69 GiB)
[1413652.903140] sd 41:0:0:0: [sdc] No Caching mode page present
[1413652.903144] sd 41:0:0:0: [sdc] Assuming drive cache: write through
[1413652.905638] sd 41:0:0:0: [sdc] No Caching mode page present
[1413652.905642] sd 41:0:0:0: [sdc] Assuming drive cache: write through
[1413652.915154] sdc: sdc1

    Do not mount any partitions the card might contain (or unmount any partition if automatically mounted) as you will be writing to the entire block device.

    Using an incorrect device node in the next step might destroy all data on your computer hard drive.

    Flashing the microSD card requires two artifacts generated by the Yocto build:

    • The compressed image file: <image-name>-ccimx6sbc.wic.gz

    • The corresponding block map file: <image-name>-ccimx6sbc.wic.bmap

    Both files must be present in the same directory when running bmaptool.

  3. Write the image file to the microSD card with this command:

    $ sudo bmaptool copy <image-name>-ccimx6sbc.wic.gz /dev/<sdcard>

Substitute the bootloader

The .wic.gz image contains the bootloader of the default variant of the ConnectCore 6. Attempting to boot it on variant with different SoC revision or RAM memory might result in unexpected behavior. You can overwrite the bootloader on the default image with the one corresponding to your SoC and variant by raw writing it to the microSD card as follows:

$ sudo dd if=<filename.imx> of=/dev/<sdcard> bs=1k seek=1 oflag=sync

See U-Boot files by variant.

The microSD card is now ready.

Boot the target from microSD card

  1. Power off the device.

  2. Insert the microSD card on the socket of the ConnectCore 6 SBC

  3. Change the boot mode switches to boot from the microSD:

    ON
    1 2

  4. Power on the device.

The target boots from the microSD.