43.6.22 Register Write Protection

To prevent any single software error from corrupting ISC behavior, certain registers in the address space can be write-protected by setting the bits WPCFGEN, WPITEN, WPCREN in ISC_WPMR.

If a write access to a write-protected register is detected, the Write Protection Violation Status (WPVS) flag in ISC_WPSR is set and the Write Protection Violation Source (WPVSRC) field indicates the register in which the write access has been attempted.

The WPVS bit is automatically cleared after reading ISC_WPSR.