[SOLVED] Write to a PLC datatype REAL?

I have a REAL datatype in my PLC. When I import the tag in Ignition 8.1 it automatically brings in an integer. I then manually change it to a double data type in my tag editor. If I proceed to edit the PLC value to something like 160.5 then 160.5 appears in Ignition. However, if I modify the value in Ignition to 161.5 the PLC changes to 161 (rounds down).

Is this a limitation of Ignition or am I missing a setting?

What kind of PLC? What driver are you using?

Studio 5000 Logix Designer v32.02.00

5069-L310ERMS2 Compact GuardLogix 5380 Safety Controller

Allen-Bradley Logix Driver

Is it just displaying an integer value or is the tag type actually Int4 instead of Float?

Hmm, well the only thing I can think that would cause the behavior you’re seeing is the format string. Nothing else would round down a number like that, and since your tag type is correct and you are seeing some decimal values I don’t think it’s a problem with the value being converted to integer.

edit: ah, I read this wrong…

Where/how are you writing the value in Ignition? Bi-directional binding?

You helped me narrow down the problem. I added a 2nd test tag in my PLC of datatype REAL and was able to write 160.5 to it so that gave me a clue as to what happened. I had changed my first tag datatype from DINT to REAL and downloaded earlier today so the gateway must not have recognized it for whatever reason. I restarted the Ignition gateway and the first tag started responding to decimal value writes from Ignition also.

Ahh… yes, that was/is a known issue when changing datatype in the program after Ignition has browsed. What version of Ignition are you using?

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Hmm, okay thanks. I thought we had fixed this at some point.

Could be Edge related? Thanks for the help though. Talking it out helps.