Allwinner A23 - Firmware
For a custom embedded system (e.g., running mainline Linux):
Build U-Boot
make CROSS_COMPILE=arm-linux-gnueabihf- A23-OLinuXino_defconfig
make
Build mainline Linux (5.x+ supports A23)
Enable ARCH=sunxi and use sun8i-a23.dtsi device tree.
Create a bootable SD card
Boot via FEL (for debugging)
sunxi-fel uboot u-boot-sunxi-with-spl.bin
A23 tablets utilize various types of NAND flash memory. Firmware images are often compiled for specific NAND chip sizes and geometries. Flashing firmware intended for a different NAND chip size usually results in "NCC" (NAND Check Failed) errors or boot loops. Customizers often modify the sys_partition.fex file to align partition sizes with the physical hardware.
Build systems
Bootloader/kernel replacement process (typical)
Reverse-engineering resources
You might be searching for Allwinner A23 firmware if your device suffers from:
Flashing stock firmware restores the device to its original factory state, as if you just unboxed it.
A23 is hard to fully brick due to FEL mode.
FEL key combinations:
Recovery steps:
Firmware tampering
Binary blobs
Update integrity
Mitigations
Some A23 tablets ignore key combinations. Short FEL pin to ground on the PCB (usually a test point labeled FEL or TP).