Jetson Nano RTC wake immediately wakes

Autonomous Machines Jetson & Embedded Systems Jetson Nano
1

Hello,

We are designing a device to reside in a vehicle and be powered through the car battery. We are attempting to reduce the power consumption as much as possible when the device is not in use. I have read in other forum topics that the command sudo rtcwake -m mem -s 60 should put the nano into a low power mode for 60 seconds. However, when running this command the device turns off for roughly 1 second and immediately comes back up. This is the output from the system:

$ sudo rtcwake -m mem -s 60
rtcwake: assuming RTC uses UTC...
rtcwake: wakeup from "mem" using /dev/rtc0 at Tue Nov 17 20:27:01 2020
rtcwake: write error

Any information on why this command doesn’t work as described in the other forum post would be very helpful. I can provide any other supplemental information needed.

Thank you!

3

Not sure as I have no Nano for checking, but you may try this.

5

Which software release are you using?

6

We are using Jetpack 4.4 and L4T 32.4.3. We have modified the kernel and device tree to add support for 2 i2c devices, but there are no other changes.

8

Hi benx0aoa,

We tried on JP-4.4.1 (r32.4.4), there are no issue.

$ sudo rtcwake -m mem -s 60
rtcwake: assuming RTC uses UTC ...
rtcwake: wakeup from "mem" using /dev/rtc0 at Thu Nov 19 02:54:44 2020

—> After 60 seconds, rtcwake.