Details:

MCU_RESETSTATz goes high periodically for a short duration and then low again while MCU_RESETz is still asserted low. This issue is seen only when MCU_RESETz is asserted low for greater than 100us. The device remains in reset while MCU_RESETz is low; the advisory only applies to the signal MCU_RESETSTATz.

Workaround(s):

Any one of the following could be used as a workaround for this advisory

• Do not use MCU_RESETz in a functional system. MCU_RESETz can still be used for debug, realizing the errata limitation.
• Limit the maximum low duration of MCU_RESETz to less than 100us.
• Use Main Domain RESETSTATz instead of MCU_RESETSTATz. MCU_RESETz also causes a Main reset, so Main Domain RESETSTATz could be used for device reset observation. Consult the datasheet for RESETSTATz timing specifications.
• For new designs, the circuits which produce Main Domain reset and MCU Domain reset should be combined with an AND gate as an input to RESETz. Also connect MCU Domain reset circuit to the MCU_RESETz input. This will provide full functionality of MCU warm reset using MCU_RESETz and MCU_RESETSTATz to indicate status of MCU domain reset. RESETz will be triggered on either a MAIN domain reset or MCU domain reset by using the AND gate.