45.6.12 Register Write Protection
To prevent any single software error from corrupting USART behavior, certain registers in the address space can be write-protected by setting the WPEN bit in the USART Write Protection Mode Register (US_WPMR).
If a write access to a write-protected register is detected, the WPVS flag in the USART Write Protection Status Register (US_WPSR) is set and the field WPVSRC indicates the register in which the write access has been attempted.
The WPVS bit is automatically cleared after reading the US_WPSR.
The following registers can be write-protected:
- USART Mode Register
- USART Baud Rate Generator Register
- USART Receiver Timeout Register
- USART Transmitter Timeguard Register
- USART Manchester Configuration Register
- USART LON Mode Register
- USART LON Beta1 Tx Register
- USART LON Beta1 Rx Register
- USART LON Priority Register
- USART LON IDT Tx Register
- USART LON IDT Rx Register
- USART IC DIFF Register