The NX's RTC can not work much time

[DaveYYY]

@ultwcz1997

But it can work one day at TX2, so I don’t know what happened at the NX.

I’m not sure about the design of your carrier board so I cannot comment much here,
but we still recommend using a coin battery for your purpose.

@ultwcz1997

@ultwcz1997

I found the NX used device rtc1(tegra_rtc c2a0000.rtc: registered as rtc1) default.
Although setting rtc time by hwlock, it will reset when power is off every time(1970-1-1).

This is correct?

Yes, because rtc1 is inside the Tegra SoC, and is not connected to any external power supply.
Only rtc0 on the carrier board can save the time after power off.