17 Oct
1997
17 Oct
'97
12:10 p.m.
_VERY_ few computers use the mains frequency for
anything other than
possibly a heatbeat interrupt (in which case the real time clock will
keep bad time, but nothing else should fail).
Actually (in the U.S.), running a clock off of the line is a
very accurate way to make a real time clock. The utilities must keep their
AC no more than ten cycles (1/6 second) off of what the NIST clock says
it should be. In the long term, it proves to be much more accurate than
crystal control, especially the crummy crystals used in computers.
Of course, once the power fails, time stands still...
William Donzelli
william(a)ans.net