Studio 5000 COP (Copy)

Question about COP and UDT's in Studio 5000.

I have a UDT structure with various data types that is reporting (according to the properties tab in the UDT) to be 252 bytes.

If I wanted to copy this entire UDT variable into another variable with the same UDT would 252 be the number I enter at the end of the instruction?


The help file for COP uses the term 'elements' for what to put as the last input but it also shows a calculation for 'bytes' so I'm not sure exactly what they are referring to.

The length is in units of the destination type. So in your case it would be 1.

Thank you.

I am confused on why the documentation has a 'byte' calculation in it then.

The COPy command won't write past the end of the destination. But lets say you have an 8 element array being copied to a 10 element array of the same type. If your length is 10 then, once the COPy has copied the first 8 elements it will continue picking up whatever garbage is past the end, in memory, of the source array. The byte count is basically a sanity check. It is even more important if you are copying from one type to a different type.

bernie_carlton said:

The byte count is basically a sanity check

Click to expand...

Good thing the PLC is only checking it's own sanity and not that of it's programmer, or there'd be a whole lot more faulted PLC's out there