Set the dip-switchs near the ethernet Jack to “SD boot mode” (Make sure CCI is ON). Boot mode configuration → refer this link
Connect Power and watch the LED status
One the Green led goes out and only RED is on. This may take 40seconds ~ 3minutes. And remove the power supply.
Set the dip switchs back to eMMC. Boot mode configuration → refer this link
Remove the microSD card
Proceed with normal power up with your peripherals attached.
After checking the Android on eMMC, you can install other Linux OS images on the eMMC later.
Recoverying eMMC with Micro SD card
This instruction requires USB-UART and terminal application on your desktop.
Set the switch (SW1) to boot with MicroSD on the board
Insert the Micro SD flashed with booting image into its slot and power on. You must stop at U-boot once the board is started.
Invoke the commands below to copy the boot loader image from Micro SD to eMMC. Once copying is done, set the switch (SW) to see if the board can boot with eMMC.