VAR-SOM-AM43 Yocto NAND Recovery

NAND Recovery introduction

As an easy and fast way to recover the VAR-SOM-AM43 NAND flash, Variscite provides a recovery SD card image that can be used to install the pre-built Linux and Android systems.
This SD card image includes a script (nand-recovery.sh) that installs all the boot images and root file-system.

Preparing rescue SD-Card

• Plug your SD card to your Linux machine, run dmesg and see what device is added (i.e. /dev/sdX)
• gunzip am43-som-nand-recovery-sd.vX.img.gz (get latest)
• dd if=am43-som-nand-recovery-sd.vX.img of=/dev/sdX bs=128k

Creating Variscite's prebuilt rescue SD-Card

• Plug-in the supplied SD card to your Linux HOST PC, run dmesg and see which device is added (i.e. /dev/sdX)
• Download am43-som-nand-recovery-sd.vX.img.gz ( latest which is available on Variscite's FTP)

$ gunzip am43-som-nand-recovery-sd.vX.img.gz
$ sudo dd if=am43-som-nand-recovery-sd.vX.img of=/dev/sd<span style="color: rgb(255, 0, 0);">'''X'''</span> bs=128k
Replace /dev/sdX with your true device, You can find it with dmesg.

Connect target debug serial to linux host

Follow : http://www.variscite.com/images/stories/DataSheets/VAR_DVK_AM43_Quick_Start_Guide.pdf
to connect target serial debug port to host PC

Boot NAND recovery SD-Card

• Power-off the board.
• Insert the SD card into the SD/MMC slot of the carrier board (DVK)
• Push SW1 to SD-Card mode (On), and SW2 to non-eMMC (off)
• The board will automatically boot into Linux from SD-Card
• login as 'root', no password is required

NAND recovery script usage

NAND recovery script usage:

/sbin/nand-recovery.sh 

This script installs the Linux binaries on the VAR-SOM-AM43 NAND-Flash.