Requesting Overview Diagnostics - Siemens SIMATIC S5 Manual

S5-95U – addressing, accessing the distributed I/O and diagnostics with STEP 5

10.3.1 Requesting overview diagnostics

Overview In diagnostics word EW 56, each bit is assigned to a DP slave. A "1" means
diagnostics
that the DP slave in question has reported diagnostics or that the DP slave
cannot be addressed by the DP master.
Structure of
The table below shows the structure of overview diagnostics:
overview
diagnostics
Table 10-3 Overview diagnostics
Diag- Input Bits correspond to the DP slaves with lowest to highest station numbers:
nostics byte
7
Over-
56 7
view
di diag-
57 15
nostics
Interpreting over-
Query the EW 56 in the STEP 5 application program and call the FB 230.
view diagnostics
When you call the FB 230, the bits in EW 56 are reset.
Example The STEP 5 application program below shows how overview diagnostics can
be interpreted.
AWL
.
.
.
: L KM 00000000 00000000
: L EW 56
: !=F
: BEB
: SPB FB230
What to do next On the basis of the overview diagnostics, you can see what kind of
diagnostics message you have to deal with. You should now analyze the slave
diagnostics.
ET 200 Distributed I/O System
EWA 4NEB 780 6000-02a
(lowest station number: E 56.0
highest station number with 16 DP slaves: E 57.7)
6 5 4
6 5 4
14 13 12 11
Explanation
custom application program
load diagnostics word EW 56
no station with errors?
if errors, then request station
diagnostics with FB 230
3 2 1 0
3 2 1 0
10 9 8
Format of
data
received
KM
KM
10
10-5