The boot process begins with code hardwired into the chip’s (mask ROM). This is read-only and cannot be altered. On the A133, the Boot ROM performs minimal hardware initialization, then checks boot pins (e.g., NAND, eMMC, SD card, USB-OTG).

The Allwinner A133 is a reliable workhorse chip, but it requires patience when it comes to software maintenance. Because it powers so many different generic tablets, there is no universal "one-size-fits-all" firmware.

The A133 relies on a heavily customized (Das U-Boot) as its main bootloader. Allwinner’s sunxi platform U-Boot includes: