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WhiteWizzard
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Joined: 05/04/2013
Location: United Kingdom
Posts: 2932

Posted: 09:58am 21 Jun 2016

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I have just seen a line of code where you set mth=mth-1. This could also be causing your issue!

lew247

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Joined: 23/12/2015
Location: United Kingdom
Posts: 1702

Posted: 10:06am 21 Jun 2016

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mth = mth - 1

is in Geoff's original GPS code, and your's from the page before this one

I was wondering what it was for - or what it did - I still don't know

if no GPS data is received then it goes back to "searching for satellites"

EDIT:

I've just loaded up the gps clock program on it's own with nothing else and I'll leave that running overnight and see if any errors "pop up"

I suspect that there will be none, which means that "SOMEHOW" the code for the rest of the weather station is making the gps clock fail - which I cannot understand how it could
Edited by lew247 2016-06-22

WhiteWizzard
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Joined: 05/04/2013
Location: United Kingdom
Posts: 2932

Posted: 10:19am 21 Jun 2016

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@lew247

As something we previously discussed; here is the code that has appeared on TBS regarding calculating DOW from date:

dim DOW$(6) length 9
DOW$(0)="Sunday":DOW$(1)="Monday":DOW$(2)="Tuesday":DOW$(3)= "Wednesday"
DOW$(4)="Thursday":DOW$(5)="Friday":DOW$(6)="Saturday"

Year=VAL(MID$(DATE$,7,4)):Month=VAL(MID$(DATE$,4,2)):Day=VAL (MID$(DATE$,1,2))
print DOW$(DayOfWeek(Year, Month, Day))

end

function DayOfWeek(year, month, day)
a = int((14-month)/12)
m = month + 12*a - 2
y = year - a
DayOfWeek = (day + y + int(y/4)-int(y/100)+int(y/400)+int(31*m/12)) mod 7
end function

Originally came from TZA (now MicroBlocks) and modified by Grogster . . . .

lew247

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Joined: 23/12/2015
Location: United Kingdom
Posts: 1702

Posted: 01:19am 14 Sep 2016

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Can anyone explain to me how this works?

Looking at it - I can see that if DST occurs, the code adds 60 minutes to the time to correct the clock
However I cannot understand how it removes the 60 mins when the DST changeover occurs

[code] ' convert the time to minutes since midnight 1st Jan 2014
' then add/subtract the timezone and if required add daylight saving
' this calculation takes just 15mS at 40MHz
mins = GetMins(year, month, day, hour, min)
mins = mins + TimeZone * 60 ' adjust for the timezone
If mins < GetDST(year, dme, dhe) Or mins > GetDST(year, dms, dhs) Then
mins = mins + 60 'adjust for AWST DST
EndIf[/code]

Phil23
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Joined: 27/03/2016
Location: Australia
Posts: 1667

Posted: 12:09am 15 Sep 2016

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It doesn't need to remove the 60 minutes, it just does not add it.

It looks like each time it'd called it starts off working from GMT.

Phil.

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