Atmel Evaluation Kit AT91SAM9X25-EK AT91SAM9X25-EK Data Sheet

Product codes
AT91SAM9X25-EK
Page of 1151
838
SAM9X25 [DATASHEET]
11054E–ATARM–10-Mar-2014
39.7.10 Write Protection Registers
To prevent any single software error that may corrupt USART behavior, certain address spaces can be write-protected 
by setting the WPEN bit in the USART Write Protect Mode Register (US_WPMR).
If a write access to the protected registers is detected, then the WPVS flag in the USART Write Protect Status Register 
(US_WPSR) is set and the WPVSRC field indicates in which register the write access has been attempted.
The WPVS flag is automatically reset by reading the USART Write Protect Mode Register (US_WPMR) with the 
appropriate access key, WPKEY.
The protected registers are: