Need Profibus DP & Profibus PA status on HMI

How do you read out the diagnosis data of a PROFIBUS DP slave with the SFC13 "DPNRM_DG" and how do you evaluate the data in the user program?
detect lost stattion after Y-link

Every PA instrument sends 5 bytes to the DP master in a cyclic fashion. One way of doing the diagnostics of individual PA slaves is to use the 5th byte of data that you read out (the first 4 bytes are the present value sent by the instrument, in REAL floating-point format). This last byte is the Status byte of the instrument, and varies with each instrument (informatoion will be found in the user manual, see the attachment for an example).
Our program would read this status byte from all our PA instruments and detect when the staus changed 9comparing the status byte value with known codes), indicating loss of communication with the DP master. We would generate an alarm on the HMI panel when that was detected.

Hope this helps,
Daniel Chartier