Android Recovery SD card

From Variscite Wiki
Android recovery SD card

Variscite provides a recovery SD card image based on demo Yocto distribution that can be used to install Android demo into the internal storage of the SOM.

1 Download the recovery SD card image

Download the latest recovery SD card from Variscite's FTP server:
See the recovery SD card changelog.
Note: Some web browsers have removed FTP support. Please see our FTP wiki page.

2 Write the image to an SD card

During the SD card image writing all files and partitions are erased from target device.
Double check that the device is correct to avoid accidentally overwriting a different device and potentially damaging your existing operating system.

2.1 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)

$ sudo umount /dev/sdX?*
$ zcat <image name>.img.gz | sudo dd of=/dev/sdX bs=1M && sync

(Replace /dev/sdX with your actual device)

2.2 Using a Windows based host

  • Download Win32 Disk Imager from: and install it.
  • Extract downloaded <image name>.img.gz file to get <image name>.img (using 7-Zip for example)
  • Insert your SD card into your PC.
    No need to format the SD card before writing the image to it, as the card will be formatted once it will be flashed.
  • Run the file named Win32DiskImager.exe (in Windows 7, 8 and 10 we recommend that you right-click this file and choose “Run as administrator”). 
  • If the SD card (Device) you are using isn’t found automatically. Click on the drop down box and select it 
  • In the Image File box, choose the <image name>.img file you have extracted previously 
  • Click Write 
  • After a few minutes, you receive a notification that your SD has been created successfully. 

2.3 Using a Mac OS X host

Use the dd Utility for MAC OS X to flash .img files to your SD card

3 Boot from SD card and flash the SOM's internal storage

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

3.1 Flash from GUI

3.2 Flash from command line

  • Login as root (no password)
  • From Linux command line, run one of the following scripts:
$	- Install Android on eMMC (Follow instructions)
$	- Install Yocto on eMMC or NAND flash (Follow instructions)

3.3 SD card image file tree

├── Android
│   ├── boot.img
│   ├── dtbo-imx8mp-var-dart.img
│   ├── dtbo-imx8mp-var-som.img
│   ├── dtbo-imx8mp-var-som-ov5640.img
│   ├── super.img
│   ├── u-boot-imx8mp-var-dart.imx
│   ├── u-boot-imx8mp-var-dart-uuu.imx
│   ├── vbmeta-imx8mp-var-dart.img
│   ├── vbmeta-imx8mp-var-som.img
│   └── vendor.img
└── Yocto
    ├── rootfs.tar.bz2
    └── imx-boot-sd.bin

The and script files are located at /usr/bin/