Re: [foxboro] Day of Week

On Tue, Jun 9, 2009 at 10:38 AM, Jerry Hidahl<Jerry_Hidahl@xxxxxxxxxxxx> wrote:
> But if it's really critical, use the station block parameters and a seven
> day counter. Then devise a way to fire it off the first time on the right
> day. Preloading the counter would take care of that. You can use a much
> more complicated method of calculating the day of the week, but you won't
> necessarily get a better result.

then you have to be careful that upgrades and cp reboots don't foul up
your counter. if your calc block with a dow calculation works, then it
works and will continue to work. it is fire and forget. using a 7 day
counter  may seem to work now, but is not very robust. i think the
best practice in this case is running the algorithm in a calc block,
you get a robust method that runs in a CP and since it is only based
off of a CPs day, month, and year variables, no counter is involved,
so it cannot get out of sync because of reboots or upgrades.

but as with most things, there are a multitude of ways to solve the
same problem, pick the method that suits your fancy

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