I am working on a project where my *nix box will talk to a PLC.  (A PLC
is sort of a brain-damaged computer...)

The PLC in question returns the date in the following 6 byte sequence:

0	year (0-99)	current year (BCD value)
1	month (1-12)	current month (BCD value)
2	day (1-31)	current day (BCD value)
3	hour (0-23)	current hour (BCD value)
4	minute (0-59)	current minute (BCD value)
5	second (0-59)	current second (BCD value)

The year is assumed to start at 2000.

I need to convert this monster to a *nix type long int (32 bit) date and
back.

On the PLC I have a BCD to int conversion which will take byte-pairs and
covert them to 16 bit ints.  I can multiply, divide, etc.

From this I need to build the *nix date....

I can't quite get my head around the conversion algorithm.  Most
resources on the web use stuff like PERL and awk, none of which I have
available.

So.... Anyone know the algorithm for calculating the *nix date?

Thanks,

--Yan

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In <12rco513dfbhkf7@corp.supernews.com> CptDondo <yan@NsOeSiPnAeMr.com> writ
es:

> I need to convert this monster to a *nix type long int (32 bit) date and
> back.

Fill in a "struct tm" with the values from the PLC, then call mktime()
on it.

--
John Gordon             "... What with you being his parents and all,
gordon@panix.com         I think that you could be trusted not to shaft
him."  -- Robert Chang, rec.games.board

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