Can I install a supercap charging circuit on a custom board to replace a coin battery?

Robotics & Edge Computing Jetson & Embedded Systems Jetson Orin Nano
1

Hello,

Can I install a supercap charging circuit on a custom board to replace a coin battery?
image

Thank you.

3

That’s ok.

1 Like
4

Hello,

If I want to maintain rtc using the supercap added to the carrier board like this, which one of /dev/rtc* should I read?

manager@ubuntu:~$ sudo hwclock -r
[sudo] password for manager:
1970-01-01 09:01:41.214855+09:00
manager@ubuntu:~$ sudo hwclock -r -f /dev/rtc1
1970-01-01 09:01:51.222914+09:00
manager@ubuntu:~$ sudo hwclock -r -f /dev/rtc0
1970-01-01 09:01:54.581129+09:00
manager@ubuntu:~$ timedatectl
               Local time: Thu 1970-01-01 09:02:04 KST
           Universal time: Thu 1970-01-01 00:02:04 UTC
                 RTC time: Thu 1970-01-01 00:02:04
                Time zone: Asia/Seoul (KST, +0900)
System clock synchronized: no
              NTP service: active
          RTC in local TZ: no
manager@ubuntu:~$ ll /dev/rtc*
lrwxrwxrwx 1 root root      4 Mar 28  2023 /dev/rtc -> rtc1
crw------- 1 root root 249, 0 Mar 28  2023 /dev/rtc0
crw------- 1 root root 249, 1 Mar 28  2023 /dev/rtc1

Thank you.

5

It should be rtc0.

1 Like
6

In r35.x.x versions, do I need to change the kernel image by modifying CONFIG_RTC_HCTOSYS_DEVICE? In r36.3 version, do I not need to modify it?

9

There is no update from you for a period, assuming this is not an issue anymore.
Hence, we are closing this topic. If need further support, please open a new one.
Thanks

Is this still an issue to support? Any result can be shared?