TMS320F28P650SH: secure boot with changing the cmac key in otp and boot_ex1_user_cmac_key.txt

I need to use the secureboot funciton with CMAC key value  0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFE.

I had change the otp 0x7801E to 0xFFFFFFFE .

when the program runs in debug mode, CPU1BROM_calculateCMAC is pass.

but it cannot run in standalone mode.

After the failure in standalone mode, I checked the values of the chip's detection registers, and they match the OTP values.

How can i run the program  in standalone mode when the key is set to 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFE?

Btw ,when key is default all F,stand alone mode CPU1BROM_calculateCMAC is pass.