WhyCan Forum(哇酷开发者社区)

Hello. I have device with N32926U1DN cpu, which booting from SPI flash.
I want to boot from sd card. How can I make bootable SD?
Cant found any datasheets with boot description.

Here is starting log, SD booting has first priority:
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Initial RTC .Enable Access Fail - Timeout
DRAM Init..2p
SD Port 0 Booting Fail - No/Unknown Device
NAND CS0 Booting Fail - No Boot Code Header
NAND CS1 Booting Fail - No Boot Code Header
SPI Booting
     Write - 0xB0000204 = 0xFFFFFFFF
     Write - 0xB0000208 = 0xFFFFFFFF
     Write - 0xB0003008 = 0x0000805A
     Write - 0xB0003028 = 0x2AFF3B4A
     Write - 0xB0003004 = 0x00000021
     Delay 256 us
....
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