Peripherals that have non-secure security mapping have their address starting with 0x4XXX_XXXX. Peripherals that have secure security mapping have their address starting with 0x5XXX_XXXX.
Peripherals with a user-selectable security mapping are available at an address starting with:
- 0x4XXX_XXXX, if the peripheral security attribute is set to non-secure
- 0x5XXX_XXXX, if the peripheral security attribute is set to secure
Note: Accesses to the 0x4XXX_XXXX address range from secure or non-secure code for a peripheral
marked as secure will result in a bus-error.
Secure code accessing the 0x5XXX_XXXX address range of a peripheral marked as non-secure will also result in a bus-error.
Peripherals with a split security mapping are available at an address starting with:
- 0x4XXX_XXXX for non-secure access and 0x5XXX_XXXX for secure access, if the peripheral
security attribute is set to non-secure
- Secure registers in the 0x4XXX_XXXX range are not visible for secure or non-secure code, and an attempt to access such a register will generate a peripheral access error, and result in write-ignore, read as zero behavior.
- Secure code can access both non-secure and secure registers in the 0x5XXX_XXXX range
- 0x5XXX_XXXX, if the peripheral security attribute is set to secure
Note: An access to an address that is within the address range of an APB interconnect, but is not
within the address range of a peripheral, will generate a peripheral acccess error, and result in
write-ignore, read as zero behavior.