[ntp:questions] Re: NTP, Unix and the 34-year itch

Terje Mathisen terje.mathisen at hda.hydro.com
Mon Jan 26 21:01:05 UTC 2004

Darren Dunham wrote:
> The date would always "set", but one second later it would be bad.  I
> recall this particular machine only had certain years that it couldn't
> hold.  If I set it ahead to 2004, it held, but dates between 2000 and
> 2003 did not.
> The next day it didn't boot, the MB was swapped, and the clock was
> fixed.  I wonder if the time on the MB is kept in some sort of BCD
> format that a one bit error could cause a 100 year slew...

Most probably true:

At least all PC's since the 1984 IBM AT have stored the current time in 
BCD in the CMOS RTC chip.


- <Terje.Mathisen at hda.hydro.com>
"almost all programming can be viewed as an exercise in caching"

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