6.2.3 RP Register Protection

The <INPUT>R and RPxxR registers are implemented with two levels of protection:

• I/O Lock Feature – All PPS registers may only be written while CFGCON0.IOLOCK = 0; once the IOLOCK is set, the registers cannot be written.
• IOLOCK Protection – The state of the IOLOCK bit can only be changed once it is unlocked using the CFGCON0.CFGLOCK[1:0] register.

These features prevent the RP registers from being inadvertently written during normal operation because changing the pinout functionality may have detrimental system-level outcome.