Siemens SIMATIC ET 200C Manual page 153

Request
The diagnostics are loaded word by word and transferred to the diagnostics
Diagnostics word. (The load and transfer operations in this section refer to the default
diagnostics address 252).
When you use dual-port RAM addressing, the diagnostics word is located in
the basic dual-port RAM page. Before you request diagnostics for dual-port
RAM page addressing, you must select the dual-port RAM page.
A typical STEP 5 station diagnostics listing is given below:
STL
L KY (basic dual-port RAM page number)
T PY 255
L KY (station number),(code)
T PW 252
L PW 252
L KH (hex-code: no fault)
!=F
BEB
SFB FBx
ET 200C Distributed I/O Station
EWA 4NEB 812 6119-02b
Fault Diagnostics with the IM 308-B
Explanation
Page selection
(Basic dual-port RAM page number:
nx16, n=0,1,..)
Load diagnostics (station number:
3...124, code: see Table 7-5) and
transfer to the diagnostics word
(diagnostics word: in this case
PW 252).
Evaluate diagnostics word (hex-code:
see Section 7.3.1 to 7.3.5)
Fault?
Evaluate fault in FBx.
7-9