Hi,
The L138 RTC module has a field DOTW (day of the week). In reality if we know the exact date (year, month, day) we also know this DOTW, but we have tested and found that this is not dependent on other fields. For example, if we set today’s exact YY-MM-DD in the respective fields, we can set arbitrary DOTW and no alert/exception would be generated. In addition, whatever DOTW values we initially set, say 3, after crossing 23:59:59 (hh-mm-ss) of the day, it goes to the next value. So DOTW simply increments for each day count. So I guess the designer of the RTC simply didn’t make it imperative that DOTW must be consistent with the other fields with respect to the real-world calendar?
It also seems that year 00 corresponds to 2000, and 99 to 2099, because with year 00 we found that Feb.28 23:59:59 transits to Mar.1 after one second, so year 00’s calendar mapping must be divisible by 400. This question is trivial but unfound in SPRUH77. Could someone comment on this?
Paul