Introduction

The backup register contains four 32-bit registers, which are used for Realtek and users to save some data before reset happens.

The following table illustrates two reset types which can reset RTC module and backup register, which are both in AON domain. Other reset types can’t reset RTC and backup register.

Reset signal	Reset type	Description
por_rstb	POR	A power on reset is generated when power on
pdr_rstb	PDR	A power down reset is generated when a low level on the CHIP_EN pin (external reset) occurs

The power domain of RTC and backup register is illustrated below.

Item	Sleep (WoWLAN)	Deepsleep
RTC	√	√
Backup register	√	√

Note

√ means this module has power.