19.1 System Lock Register

Several modules contain registers that are protected from errant code causing unwanted changes by the system lock feature. When the system lock is in effect, which is the default state, registers protected by it are not writable. The system lock feature protects registers that are system critical such as the boot time option.

Each module that uses the system lock feature describes which register bits and functions it affects. A specific sequence of writes to the SYSKEY register unlock the access to those register bits and features.