On Mon, 6 Mar 2006, joel garner wrote:
> ts-7250 has no real time clock,
It can have - it is an oiptional extra.
> so is it that whever the board is powered on the time starts from 00:00.
> and what is the accuracy of this time..minutes, seconds, microseconds?
When it starts it start at 0 exactly :-)
A description of how unix systems handle normal time is at....
http://en.wikipedia.org/wiki/Unix_epoch
However the system clocks can provide more accurary, dependant on the
hardware, and to some extent the kernel configuration. The kernel keeps a
"jiffy" timer count of the number of system timer interrupts. These are
usually arranged to be at 100HZ, but can be patched to other values
(1024HZ is a common value).
This ref has some info....
http://www.xml.com/ldd/chapter/book/ch06.html
Use of Specific hardware counters may allow more accurate resolution. As
to Accuracy, that depends on the many factors.
I've found the free running timers on the ts7200 allow my box to keep an
accuracy of the order of 1 sec in a couple of days.
There have been some discussions on this in this list in the early days -
I suggest you search the list archive at yahoo
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