2009-09-04 08:54:26     Problem with RTC

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2009-09-04 08:54:26     Problem with RTC

Emil Bart (POLAND)

Message: 79614   




I have the problem with system time. After reboot the system time is set to other value. For example:


but after reboot  my set is missing, here is my example:


root:/> date

Wed Feb 17 03:15:50 UTC 1993

root:/> date -s 082000002008

Wed Aug 20 00:00:00 UTC 2008

root:/> reboot


after reboot:


root:/> date

Wed Feb 17 03:17:12 UTC 1993



I started to look for solving the problem on this forum and I found the following solution (update the hardware time after setting the system time ):


date -s 082012302008


hwclock -w


I did the above steps. But now when I want to check the time of rtc I receives the following message:


root:~> hwclock --show

The Hardware Clock registers contain values that are either invalid (e.g. 50th day of month) or beyo

nd the range we can handle (e.g. Year 2095).



My uclinux distribution is 06-R2-5. I think that I need the driver for rtc included in blackfin. I don't have any rtc directory in uClinux/linux-2-6-x/drivers/ . Maybe somebody can help me because I'm newbe in linux and I don't know what to do now.




2009-09-04 09:16:22     Re: Problem with RTC

Mike Frysinger (UNITED STATES)

Message: 79615   


works fine for me.  sounds like it's time to upgrade your distro.


root:/> hwclock

Sun Jan  4 20:34:40 1970  0.000000 seconds

root:/> date

Sun Jan  4 20:34:46 UTC 1970


root:/> date -s 2009.09.03-09:16

Thu Sep  3 09:16:00 UTC 2009

root:/> hwclock -w

root:/> hwclock

Thu Sep  3 09:16:07 2009  0.000000 seconds




2009-09-04 09:30:26     Re: Problem with RTC

Emil Bart (POLAND)

Message: 79616   


Thanks for reply. Yes, I know that I use a quite old distro of linux. But we use it in our company for our products and it is not so easy update the distro. I think that I don't have driver for blackfin on-chip rtc. I checked that I don't have any rtc directory in drivers directory like the latest distro has it. Do you think that hwclock will start work properly when I copy rtc directory to my distro and enable driver for blackfin on-chip rtc ?




2009-09-04 09:53:33     Re: Problem with RTC

Mike Frysinger (UNITED STATES)

Message: 79617   


the rtc framework probably didnt exist in 2006, and it wont be trivial to backport.


there was of course a driver for the rtc in that version though.  it's under drivers/char/.  whether it is bug free, i have no idea.  it is long dead code at this point.