We are having problems with the RTC_CR register (and others) being trashed during a hard kill (input power to regulators shut off, power-supplies decay, reset goes active when the 3.3V supply reaches 3.08V).
In the SAMA5D3 Datasheet Rev. 11121E (02-Feb-16), the sentence was added for several of the RTC registers (see Table 60-2, page 1867, Issue Date 03-Feb-15):
|“This register can only be written if the WPEN bit is cleared in
the System Controller Write Protection Mode Register (SYSC_WPMR)
However a search of the datasheet, of Atmel.com, etc. turns up no definition for SYSC_WPMR. Inspection of Section 7, "System Controller" shows no register definitions. Anyone know where this might be defined?
Thanks in advance!