I have time stamps in the pi archive: (all dates are DD/MM/YYYY)
01/03/2015 00:00 value = 2
09/04/2015 12:45 value = 3
In PiACE I am doing calculations every 15 mins and getting the PI values at the exact 15 min mark.
To do that I have been setting the exetime of the pi point to the time I am calculating then get the value. This appears to be working perfectly for everything I have tested except for one module that I am trying to test.
If I set the time to be 01/03/2015 08:00 it is returning the value of 2. I suspect it is doing this because it is the value in the archive prior to this datetime I have specified? Maybe exetime works like that … if it cannot find a value at the time specified it returns the previous known value in the system or maybe I have a problem with my archive or something else more sinister which is why it is retrieving values when there is no data in the archive.
or maybe when I try to reset the datetime I need to clear value first and then set the datetime??