Unruh <[email protected]> writes: >Rob van der Putten <[email protected]> writes:
>>Hi there >>Unruh wrote: >>> It depends. Some people regard the leapsecond as counting >>> 23:59:0 23:59:1 ...25:59:59 23:59:60 0:0:0 >>> while I think the leapsecond standard is actually >>> 23:59:0 23:59:1 ...25:59:59 0:0:0 0:0:0 >>> Ie it occurs on teh first second of the new year, rather than the last >>> second of the old. I assume BBC (and ntp ) follow the former. >>AFAIK, the first is the standard, the second the implementation. >Yes, the first is the definition of UTC >(http://tycho.usno.navy.mil/leapsec.html) > and I think ntp follows the second > (http://www.cis.udel.edu/~mills/leap.html)--Ie, any > rereading of the clock during the time of that leap second would give > 00:00:00 with > a usec return that advances 1 usec per reading. Ie it simply stops the clock > for > a second. The unix clock will >never show 23:59:60. Is this also true of the time indicated by gps? >Looking in the Garmin 18LVC manual it says it uses the latter-- two reports >of 0:0:0 >one second apart. OK, the leap second passed. My one ntp machine handled it fine. Here is the output from my GPS 18LVC. $GPRMC,235959,A,4915.6384,N,12310.7450,W,000.0,257.9,311208,018.9,E*62^M $PGRMF,488,345613,311208,235959,14,4915.6384,N,12310.7450,W,A,2,0,258,2,1*0C^M $GPRMC,000000,A,4915.6384,N,12310.7450,W,000.0,257.9,311208,018.9,E*63^M $PGRMF,488,345614,311208,235959,15,4915.6384,N,12310.7450,W,A,2,0,258,3,1*0B^M $GPRMC,000000,A,4915.6384,N,12310.7450,W,000.0,257.9,010109,018.9,E*63^M $PGRMF,488,345615,010109,000000,15,4915.6384,N,12310.7450,W,A,2,0,258,2,1*0A^M $GPRMC,000001,A,4915.6384,N,12310.7450,W,000.0,257.9,010109,018.9,E*62^M $PGRMF,488,345616,010109,000001,15,4915.6384,N,12310.7450,W,A,2,0,258,3,2*0A^M Ie, it repeats 00:00:00 but it also states that the difference between UTC and GPS time went from 14 to 15 on the first 00:00:00. It is also weird that on the first one, the time reported in the GPRMC string is different from that in the PGRMF. In PGRMF it is 23:59:59 that is repeated. (which is closer to the UTC definition) _______________________________________________ questions mailing list [email protected] https://lists.ntp.org/mailman/listinfo/questions
