Logix5000: Sending a UDT with MSG command

[LemmingRebel]

I am able to get the MSG command complete when the UDT is a simple string type. The calculation for the REQ_LEN is a simple one then: the length of the string (automatically calculated for you and stored as LEN), plus the 4 bytes for the LEN parameter itself.

But if my UDT has more than a string, an array of REALs for instance, the MSG command always throws one of two errors:

16#0009, Parameter error in module configuration
16#0013, Configuration data size too short

It seems like I get the 0013 error when I overshoot for the data size. But no matter what value I enter for REQ_LEN, I still get one of these errors.

If my UDT has an array of REALs, how do I find its corresponding length? And is this even my problem?

 

[LemmingRebel]

For clarification, I am writing a UDT to a PC app I've created. The PC app receives the simple string UDT...

 

[LemmingRebel]

Figured out how to do this. Message me if you need help.