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ropg / ezTime

ezTime — pronounced "Easy Time" — is a very easy to use Arduino time and date library that provides NTP network time lookups, extensive timezone support, formatted time and date strings, user events, millisecond precision and more.
MIT License
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lastNtpUpdateTime() incorrect. #46

Closed mike-s123 closed 4 years ago

mike-s123 commented 5 years ago

Shortly after things get started and NTP is updated,

myTz.dateTime(RFC850) produces "Wednesday, 10-Apr-2019 10:30:37 EDT"

but

dateTime(lastNtpUpdateTime(),RFC850) produces "Wednesday, 10-Apr-2019 18:29:37 EDT"

Seems to be a sign issue. EDT is UTC-4, and the reported time is off by 8. Or maybe it's got to do with dateTime(), not lastNtpUpdateTime().

UTC.dateTime(lastNtpUpdateTime(),RFC850) produces the expected result.

mitag commented 5 years ago

Could this have something to do with this? "If you execute multiple calls to setLocation, make sure they are more than 3 seconds apart, because the server will not answer if calls from the same IP come within 3 seconds of one another (see below)." During a test I recalled the time every second and was always shown CEST and UTC alternately, which makes a difference of 2 hours.

mike-s123 commented 5 years ago

Nope. I use setPosix (so there's no dependency on external servers), and it's only called once, during initialization. And, the data above was after a single poll of the ntp server.

ropg commented 5 years ago

Strange... I will have a look at this soon.

mike-s123 commented 4 years ago

Bug still present in 0.8.3.

myTZ.dateTime(RFC850) returns Sunday, 22-Dec-2019 16:01:05 EST 
myTZ.dateTime(lastNtpUpdateTime(),RFC850) returns Sunday, 22-Dec-2019 20:59:34 EST

The former is correct, the latter is off by +5 hours (these were shown shortly after a boot and fresh NTP sync).

ropg commented 4 years ago

lastNtUpdateTime is in UTC, which I guess you are 5 hours away from.

Try myTZ.dateTime(lastNtpUpdateTime(), UTC_TIME, RFC850)

mike-s123 commented 4 years ago

OK, that worked. Thanks.

Please update the docs - https://github.com/ropg/ezTime#datetime - which show dateTime only taking 2 arguments. ("String dateTime(TIME, String format = DEFAULT_TIMEFORMAT);")

ropg commented 4 years ago

It's there. Check out the section 'specifying time' in the manual...