VAR-SOM-MX7 Debian Recovery SD card

From Variscite Wiki
VAR-SOM-MX7 - Debian recovery SD card

Variscite provides a recovery SD card image that can be used to install the pre-built Debian images into the internal storage device of the SOM.

Download the recovery SD card image

Download mx7-som-debian-recovery-sd.vXX.img.gz (latest) from Variscite's FTP server: sftp://customerv@ftp.variscite.com/Public/VAR-SOM-MX7/Software/debian/

For more information about Variscite's FTP server, see: https://variwiki.com/index.php?title=FTP

Write the image to an SD card

Using a Linux based host

Plug-in the SD card to your Linux HOST PC, run dmesg and see which device is added (i.e. /dev/sdX or /dev/mmcblkX)

$ gunzip mx7-som-debian-recovery-sd.vXX.img.gz
$ sudo umount /dev/sdX*
$ sudo dd if=mx7-som-debian-recovery-sd.vXX.img of=/dev/sdX bs=1M; sync

(Replace /dev/sdX with your actual device)

Using a Windows based host

Download Win32 Disk Imager from: https://sourceforge.net/projects/win32diskimager/, install and run it.
Select the image file, and the SD card device - double check that the device is correct to avoid accidentally overwriting a different device.
Click on "Write".
No need to format the SD card before writing the image to it.

Recover NAND flash/eMMC

  • Power-off the board.
  • Insert the SD card into the SD card slot of the carrier board (DVK)
  • Make sure the Boot DIP switches are set to SD card: Setting the Boot DIP switches
  • Power up the board - it will boot into Linux from the SD card

Flash from command line

  • Login as root (no password)
  • From Linux command line, type the following
# debian-nand.sh	- Flash Debian into NAND flash (for SOMs with NAND flash)
# debian-nand.sh -m	- Flash Debian images with Cortex-M4 support into NAND flash (for SOMs with NAND flash)

In case you are using a SOM with eMMC, run the following command as root to install Debian on it:

# debian-emmc.sh	- Flash Debian into eMMC (for SOMs with eMMC)

(both regular device tree and device tree with Cortex-M4 support will be installed)

SD card image file tree

/opt/images/
└── Debian
    ├── imx7d-var-som-emmc.dtb
    ├── imx7d-var-som-emmc-m4.dtb
    ├── imx7d-var-som-nand.dtb
    ├── imx7d-var-som-nand-m4.dtb
    ├── rootfs.tar.gz
    ├── rootfs.ubi.img
    ├── SPL.mmc
    ├── SPL.nand
    ├── u-boot.img.mmc
    ├── u-boot.img.nand
    └── zImage
The debian-emmc.sh and debian-nand.sh script files are located at /usr/sbin/