Before touching any files, understand the A133’s boot chain. Messing this up leads to a hard brick.
✅ Device enters FEL mode ✅ Correct boot0 for A133 (not H6/A64) ✅ PMIC (AXP813) power sequence configured ✅ DRAM parameters match your PCB layout ✅ Kernel + DTB compiled for A133 ✅ Flashed via PhoenixSuit or written via dd correctly allwinner+a133+firmware+work