Need to read SLC float to Controllogix

[JJT_MO]

OK, having a brain **** here, anyone remember if it's possible to read a floating point value from a 5/04 from a controllogix? Trying to do this via DH+. Hardware already set up and functioning. Just can't remember if it's even possible as a float is actually a 2 element structure in an SLC.

 

[jac]

Bom Dia
It is always easier to msg from the CL5K to a SLC or PLC5 do to the path having extra steps on the CL5K side. Just set up an array (controller scope) select as the source and pick your float in the SLC and go. see the attached MSWord doc. Oh yeah condition the msg instruction with a timer.

 

[rguimond]

Why not just read the variables you're using to create the float from the 5/04 and do the calculation in the controllogix?

 

[JJT_MO]

The mechanics of how to read/write are no problem! I do that often. I'm just having trouble getting a floating point.

 

[JJT_MO]

I'm reading from some legacy code and was trying not to reinvent the wheel. There are a lot of calculations going on to get to the final result, including captures at various times and so forth to attempt to move that over at this point would be time consuming and I'm pushed for that precious commodity at this time. But thanks!

 

[sthompson]

OK, having a brain **** here, anyone remember if it's possible to read a floating point value from a 5/04 from a controllogix? Trying to do this via DH+. Hardware already set up and functioning. Just can't remember if it's even possible as a float is actually a 2 element structure in an SLC.

I just tried it on one of my systems, and it worked with no problems. I used a SLC Type Read, specified F8:0 as the Source and SLC_FLT_RD2 Typed Real as the Destination, Elements 2, and Voila, live Data. That particular 5/04 only has two Floats defined, so that is all I could read out of it.

Stu....

 

[JJT_MO]

OK, thanks! Went back and tried it again, went back to step 1 and limited the number I was reading to just a few and it worked. Apparently the limit is 58 elements per read. DH+ packet size limits the number I would imagine. Anyway, I'm back on the road again, thanks all!