RTC precision?

Thaddeus P. Floryan thad at public.BTR.COM
Mon Mar 11 12:02:30 AEST 1991


In article <1991Mar5.193756.25135 at tc.fluke.COM> vince at tc.fluke.COM (Craig Johnson) writes:
>In article <1988 at public.BTR.COM>, thad at public.BTR.COM (Thaddeus P. Floryan) writes:
>> And, though I don't have the data sheets at hand, I "believe" the RTC could
>> resolve to better than 1 second but there are no "hooks" in the 3B1 to allow
>> access.  I use a similar clock in one of my own products for datestamping
>> "events".
>
>Sorry Thad.  I checked the Toshiba data sheet and found that there are
>only readable registers allowing resolution to 1 second.  There is a ...

Craig is correct; the "similar" chip about which I was thinking was made by
SaRoNiX (Palo Alto CA) who sold that operation to Epson a little while back.

Toshiba is definitely NOT Epson (yet :-)

The "1/HZ" clock provides reasonable short-interval timing as is used by the
times() call and which is used in my interpretation of the gettimeofday()
which I posted last year; the main purpose was for timing ftp operations
with better than the 1 second stats from the 1.4 WIN/3B package.

Thad Floryan [ thad at btr.com (OR) {decwrl, mips, fernwood}!btr!thad ]



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