Siemens Simatic S7-400

PROFIBUS DP
5.1 CPU 41x-3 PN/DP as DP master / DP slave
S7-400 Automation System, CPU Specifications
Manual, 10/2006, 6ES7498-8AA04-8BA0
5-7
Triggering Detection of the Bus Topology in a DP Master System with the SFC103 "DP_TOPOL"
The diagnostic repeater is available to improve the ability to locate faulty modules or an
interruption on the DP cable when failures occur in ongoing operation. This module operates
as a slave and can identify the topology of a DP chain and record any faults originating from
it.
You can use SFC103 "DP_TOPOL" to trigger the identification of the bus topology of a DP
master system by the diagnostic repeater. For information on SFC103, refer to the
corresponding online help and to the
System and Standard Functions manual. The
diagnostic repeater is described in the manual
Diagnostic Repeater for PROFIBUS DP ,
Order Number 6ES7972-0AB00-8BA0.
Reading Out Diagnostic Data with STEP 7
Table 5-3 Reading out the diagnostics with STEP 7
DP master Block or tab in
STEP 7 Application Reference
"DP Slave Diagnostics"
tab
Show slave diagnosis in clear text
on the STEP 7 interface
See the section on hardware
diagnostics in the STEP 7 online help
system and in the Programming with
STEP 7 manual
SFC13 "DPNRM_DG" Reading out slave diagnostics
(store in data area of the user
program)
SFC, see System Software for S7-
300/400, System and Standard
Functions
reference manual. For the
structure of other slaves, refer to their
descriptions.
SFC59 "RD_REC" Reading the data records of S7
diagnostics (stored in the data area
of the user program)
SFC 51 "RDSYSST" To read out partial SSL lists. Call
SFC51 in the diagnostic interrupt
using the SSL ID W#16#00B3 and
read out the SSL of the slave CPU.
SFB 52 "RDREC" For DPV1 slaves
Reading the data records of S7
diagnostics (stored in the data area
of the user program)
SFB 54 "RALRM" For DPV1 slaves:
To read out interrupt information
within the associated interrupt OB
CPU 41x
SFC 103
"DP_TOPOL"
Triggers detection of the bus
topology of a DP master system
with diagnostic repeaters installed
there.
System Software for S7-300/400,
System and Standard Functions
reference manual.