For an OrangePi PC (similar to a Raspberry Pi), we need to have a double boot menu:
- Linux on the SD
- Android on the USB
If there is no USB detected, Linux should boot.
If there is USB detected, a menu should appear showing two options.
We need to have Linux on the SD and Android on the USB. No other combination is possible.
OrangePi PC has no NAND, just SD card.