[S7] REAL address. DBD?

I seem to be running into an issue. I have a scaling FB in a Siemens PLC, and so it accurately displays the scaled output as a REAL. When I read it with the HMI, however, it comes in as a very large INT, or more likely, a DINT. I know that DBWxx addresses a word (INT) and that DBDxx addresses a double word (DINT), but is there a way to address a REAL?

I suspect I just use the DBWxx (since a bit is a bit to an address), but if the HMI expects an INT at this address and the PLC is writing a REAL at this address, I won't get what I want.

Advice?

(S7300 PLC. VTScada HMI)

Have you tried converting the number from REAL to DINT and see what comes up then.

I have not. This isn't really my PLC code.

My solution, at the moment, is just to re-do scaling on the unscaled input. It means scaling in two places, but it seems to work.

I know that DBWxx addresses a word (INT) and that DBDxx addresses a double word (DINT), but is there a way to address a REAL?

Click to expand...

Not 100% correct.
A word can be interpreted as a WORD or an INT.
A double-word can be interpreted as a DWORD, a DINT, a REAL or a TIME.
I think you simply have to select the datatype REAL in your Scada software, and all will be well.

That's what I figured. The SCADA doesn't have a way to typecast the incoming bits as a real vs an int. Such is life.

But, yeah, to answer my original question, there is no "DBR" for real address format.

It's ok. I got it to work by scaling in the SCADA.