Datasheet

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SAM9X25 [DATASHEET]
11054E–ATARM–10-Mar-2014
25.6 Register Write Protection
To prevent any single software error from corrupting MATRIX behavior, certain registers in the address space can be
write-protected by setting the WPEN bit in the “Write Protection Mode Register” (MATRIX_WPMR).
If a write access to a write-protected register is detected, the WPVS flag in the “Write Protection Status Register”
(MATRIX_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 MATRIX_WPSR.
The following registers can be write-protected:
 “Bus Matrix Master Configuration Registers”
 “Bus Matrix Slave Configuration Registers”
 “Bus Matrix Priority Registers A For Slaves”
 “Bus Matrix Priority Registers B For Slaves”
 “Bus Matrix Master Remap Control Register”