Le 14/02/2012 12:09, qber_ a écrit :
Hello all.
I want to discuss an option of Wallclock device framework.. Now the wallclock
supports two option : init_get and set_get. This functions support time counted
from 1970-01-01 00:00:00. The idea is to add the support for calendar insted of
seconds counter. Most of applications uses calendar not seconds counter.
The change for handling date and time for me is a result of working with
STM32F2x processor which has calendar based RTC. The is no sense for converting
calendar to seconds and then back again to calendar.
The problem is which date and time format should be selected (if this change
will be added to officail reposotory).
Best Regards
Qber
Hello Qber,
time_t (or any similar integer counter) is used everywhere inside CPUs,
calendar time is used only to interface with entities externals to the
MCU/CPU like humans, files/databases, network. Usually there is much
more internal time calculations than time data output from a CPU in
calendar representation. It's very hard to see any gain by using
nightmarish calendar calculations when simple integer arithmetic can be
used instead. Write a function that adds a variable amount of time to
data represented as calendar date/time and compare it to an integer
addition. Conversion functions between time_t and calendar date/time
exist from 1970-01-01 00:00:00. Even Windows uses an integer
representation, even probably the Maya as shown by their overflow
problem at the end of the year.
Bernard
