On Thursday, 27 August 2020 08:07:53 UTC+3, Niresh Kumar wrote: > > I've have tested both BB-I2C1-RTC-DS3231.dtbo and BB-I2C2-RTC-DS3231.dtbo > in the new image 4.19.94-ti-r42, they mount rtc1 in /dev but system > time is not updated with rtc1. Please let me know if any other procedure is > required and also procedure to update external rtc1 time when the > internet is connected. >
That's unfortunate. Still, logs from the uboot bootloader (observed from the onboard TTL level UART) or the Linux kernel (from dmesg or syslog) might indicate what's wrong. To get effective help, please post output from "sudo /opt/scripts/tools/version.sh" and the content of your "/boot/uEnv.txt" file. > One thing i have observed, with BB-I2C1-RTC-DS3231.dtbo the timedatectl > command displayed "RTC time: n/a" not system time as in normal condition. > Weird. I would interpret it as the AM335x internal RTC having been pushed aside from /dev/rtc0 successfully, but the external RTC does not pick the device up. > Please clarify the following points > 1. How do you say the rtc chip is in i2c bus one. Using i2cdetect command > "i2cdetect -r 2" , 0x68 external device showed in i2c bus two. > There might be differences in how different systems count buses. One might start from 0 and other from 1. TBH it's always been confusing as hell for me. > 2. I understand overlay is an out of box approach. In 4.4.30-ti-r64, > system time updated with "echo ds3231 0x68 > > /sys/class/i2c-adapter/i2c-1/new_device; hwclock -r -f /dev/rtc1" in > /etc/rc.local. > Is there any problem if I use this approach in older images? > No, go right ahead. You're left with the task of figuring out a solution for syncing time between the RTC, system clock and NTP - as you wrote out in the very first message. My suggestion was to have systemd-timesyncd do it for you, but you can, as an alternative, do it yourself with a few bash scripts. -- Kind regards, Tarmo -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/37bcd7f5-7e35-4c1f-9507-0716056b2c26o%40googlegroups.com.
