Tool/software:
Problem:
The Boot mode is SD card priority mode, and the system cannot boot from SD card.
After the SDCD signal is inserted into the SD card, the level of CLK will become low, and the CLK level will not change.
Verification 1:
If the SD card is inserted into the mainboard, the SD card can be started normally using the same Boot mode.
Verification 2:
If the Boot mode is changed to UART, the debug interface will print 'C'.