Diagnostic with cpu317 and et-220m by profinet

Hi all,

I am starting programming Siemens drivers and I just learn it.

I have problem with diagnostic et200m module with cp341 by profinet. I used SFC51 "RDSSYST" in OB1, but I don't know parameters. I can't use B2 in SZL_ID, because et 200m is on other rack. When I use B3 or B1 or B4 any diagnostic address doesn't work. Always I have error 8083 in RET_VAL parameter. In Index parameter I tried all possibilities I think.

I search a lot of answer, maybe I should use another function? But what, from all what I found, SFC51 is the best, I think.

Thank you for answers.:)

I attached my program.