2.3.3 nPORESET handling

nPORESET directly resets the Reset Syndrome registers and Mask register.

nPORESET is combined with the masked and combined reset requests from watchdog timers, the RESETREQ input, the SWRESETREQ register value, and the negative-edge detect and stretched signal of nSRST. This generates the internal combined system Cold reset signal nPORESETAON, which resets almost all logic within the system.


nPORESETAON resets the PPU, in each PPU-controlled power domain. The PPU then resets the other logic in the domain using its reset pins:

  • DEVWARMRESETn if the domain does not support retention.
  • DEVRETRESETn if the domain supports logic or full retention.
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