Hello,
1. Can I periodically check the value of the register settings during operation?
Yes, you can read protected registers with no limitation.
1-1. If possible, how to check or an example project would be appreciated.
Simply perform read and compare it in your SW with expected values.
But I see no sense in this, as if there is any access to protected register, exception is called.
2. Among the registers that are set at Init, are there any registers that can be written and changed with arbitrary values?
Ex) Write and read with specific values (0xAA, 0x55, etc.) to the register area used, and recover the register after checking the physical integrity.
You have 2 lock possibilities:
1. Soft lock - can be unlocked by sequence
2. Hard lock - unlocked only on power on reset.
For more details please refer to Chapter 55 Register Protection (REG_PROT) of reference manual.
Best regards,
Peter