PROFIBUS DP communication module
9.9 Diagnosis with STEP 7
3RW44 soft starters
Manual, 03/2017, NEB535219502000/RS-AB/008
173
STEP 7 user program
STL
Explanation
CALL SFC 13
REQ :=TRUE
LADDR :=W#16#3FE
RET_VAL :=MW0
RECORD :=P#DB82.DBX 0.0 BYTE 32
BUSY :=M2.0
Read request
Diagnostic address
RET_VAL of SFC 13
Mailbox for diagnostic data in DB82
Read process runs over several OB1
cycles
9.9.3
Structure of the slave diagnostics
Figure 9-4
Structure of the slave diagnostics
Note
The length of the diagnostics message frame varies between 13 and 32 bytes. The length of
the diagnostics message frame last received can be seen in STEP 7 from the RET_VAL
parameter of SFC 13.