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<DIV dir=ltr align=left>
<DIV dir=ltr align=left><SPAN class=120042412-22082008><FONT face=Arial><FONT
color=#0000ff><FONT size=2>no advantage<SPAN class=964052512-22082008> or
disadvantage</SPAN></FONT></FONT></FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=120042412-22082008><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=120042412-22082008><FONT face=Arial
color=#0000ff size=2>S<SPAN class=964052512-22082008>ince S</SPAN>cott was
already using <SPAN class=964052512-22082008>the 1958 epoch</SPAN> in
his implementation, I was going to use it <SPAN
class=964052512-22082008>also </SPAN>so my stuff would work against his.
And for the same reason, <SPAN class=964052512-22082008>I think </SPAN>we
all should use the same epoch.</FONT></SPAN></DIV></DIV>
<DIV> </DIV><!-- Converted from text/plain format -->
<P><FONT size=2>Patrick Donahue<BR>(256) 544-5943 office<BR>(256) 721-0726
home<BR>(256) 682-9753 cell</FONT> </P>
<DIV> </DIV><BR>
<BLOCKQUOTE dir=ltr
style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #0000ff 2px solid; MARGIN-RIGHT: 0px">
<DIV class=OutlookMessageHeader lang=en-us dir=ltr align=left>
<HR tabIndex=-1>
<FONT face=Tahoma size=2><B>From:</B> Ray, Timothy J. (GSFC-583.0)
[mailto:timothy.j.ray@nasa.gov] <BR><B>Sent:</B> Thursday, August 21, 2008
2:21 PM<BR><B>To:</B> Donahue, Pat<BR><B>Cc:</B>
sis-ams@mailman.ccsds.org<BR><B>Subject:</B> RE: [Sis-ams] Time Tag - CCSDS
Time<BR></FONT><BR></DIV>
<DIV></DIV>
<DIV class=Section1>
<P class=MsoNormal><FONT face=Arial color=navy size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial">Sounds good
Pat.</SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial color=navy size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial"></SPAN></FONT> </P>
<P class=MsoNormal><FONT face=Arial color=navy size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial">Just out of
curiosity, is there some advantage to using the older epoch?</SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial color=navy size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial"></SPAN></FONT> </P>
<P class=MsoNormal><FONT face=Arial color=navy size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial">Tim</SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial color=navy size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial"></SPAN></FONT> </P>
<P class=MsoNormal><FONT face=Arial color=navy size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial"></SPAN></FONT> </P>
<P class=MsoNormal><FONT face=Arial color=navy size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial"></SPAN></FONT> </P>
<DIV>
<DIV class=MsoNormal style="TEXT-ALIGN: center" align=center><FONT
face="Times New Roman" color=black size=3><SPAN
style="FONT-SIZE: 12pt; COLOR: windowtext">
<HR tabIndex=-1 align=center width="100%" SIZE=2>
</SPAN></FONT></DIV>
<P class=MsoNormal><B><FONT face=Tahoma color=black size=2><SPAN
style="FONT-WEIGHT: bold; FONT-SIZE: 10pt; COLOR: windowtext; FONT-FAMILY: Tahoma">From:</SPAN></FONT></B><FONT
face=Tahoma color=black size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: windowtext; FONT-FAMILY: Tahoma">
sis-ams-bounces@mailman.ccsds.org [mailto:sis-ams-bounces@mailman.ccsds.org]
<B><SPAN style="FONT-WEIGHT: bold">On Behalf Of </SPAN></B>Donahue,
Pat<BR><B><SPAN style="FONT-WEIGHT: bold">Sent:</SPAN></B> Wednesday, August
20, 2008 12:35 PM<BR><B><SPAN style="FONT-WEIGHT: bold">To:</SPAN></B>
sis-ams@mailman.ccsds.org<BR><B><SPAN
style="FONT-WEIGHT: bold">Subject:</SPAN></B> [Sis-ams] Time Tag - CCSDS
Time</SPAN></FONT></P></DIV>
<P class=MsoNormal><FONT face="Times New Roman" color=black size=3><SPAN
style="FONT-SIZE: 12pt"></SPAN></FONT> </P>
<P class=MsoNormal><FONT face=Arial color=blue size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: blue; FONT-FAMILY: Arial">For interoperability
sake, just like we have agreed to an "Unsegmented" CCSDS format, I suggest
that we also agree to all use the 1958 epoch as our basis, and 4 bytes of
course time (since you need that many bytes to properly contain the number of
seconds since Jan 1, 1958).</SPAN></FONT></P>
<P class=MsoNormal><FONT face="Times New Roman" color=black size=3><SPAN
style="FONT-SIZE: 12pt"></SPAN></FONT> </P>
<P class=MsoNormal><FONT face=Arial color=blue size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: blue; FONT-FAMILY: Arial">By the way, if you
are working with the Jan 1, 1970 epoch in Unix just add 378691200 and you
will have the number of seconds since Jan 1, 1958. Correct me if I am
wrong.</SPAN></FONT></P>
<DIV>
<P class=MsoNormal><FONT face="Times New Roman" color=black size=3><SPAN
style="FONT-SIZE: 12pt"></SPAN></FONT> </P></DIV>
<P><FONT face="Times New Roman" color=black size=2><SPAN
style="FONT-SIZE: 10pt"><!-- Converted from text/plain format -->Patrick
Donahue<BR>(256) 544-5943 office<BR>(256) 721-0726 home<BR>(256) 682-9753
cell</SPAN></FONT></P></DIV></BLOCKQUOTE></BODY></HTML>