PROFIBUS DP Communication Module
8.9
Diagnosis with STEP 7
8.9.1 Reading the Diagnosis
Length of the diagnosis telegram
8.9.2 Options for Reading the Diagnosis
Automation system with
DP master
SIMATIC S7/M7
Table 8-9: Reading the diagnosis with STEP 7
Reading the S7 diagnosis with SFC 13 "DP NRM_DG" (example)
Assumptions
8-26
The maximum length of the telegram is 32 byte.
Module or register in
STEP 7
SFC 13 "DP NRM_DG" Reading the slave diagnosis
This is an example of how to read the slave diagnosis for a DP slave in the
STEP 7 user program using SFC 13.
The following assumptions are true for this STEP 7 user program:
• The diagnostic address is 1022 (3FE
• The slave diagnosis should be stored in DB82: from address 0.0,
length 32 bytes.
• The slave diagnosis consists of 32 bytes.
STEP 7 user program
STL
CALL
SFC 13
REQ
:=TRUE
LADDR
:=W#16#3FE
RET_VAL :=MW0
RECORD :=P#DB82.DBX 0.0 BYTE 32
BUSY
:=M2.0
Application
(store in data area of the user
program)
).
H
Explanation
Read request
Diagnostic address
RET_VAL of SFC 13
Data compartment for diagnosis in DB82
Read
cycles
Refer to ...
Chapter 8.9.3 "Structure of the
Slave Diagnosis" on Page 8-27,
For SFC, refer to the online help
in STEP 7
operation
runs
over
SIRIUS 3RW44 manual
GWA 4NEB 535 2195-02 DS 06
several
OB1