AS-Interface Analyser
Using the Analyser
s
Subject to reasonable modifications due to technical advances.
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23.
8.
2006
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would be missing then. Eventually such an error is combined with an output slave
switching a large consumer.
7.3.5
Errors by Excess Length or by High-capacity Slaves
The analog signal on the AS-Interface line is deformed by capacitive loads, e.g.
nets with excess length or faulty slaves, and cannot be clearly recognized, in the
worst case, by the master and the slaves anymore with the consequence that com-
munication errors occurs.
Then individual slaves fail in the online statistics. Slaves which are located close
to the master are endangered empirically. But often the first repetition is already
successful (error of the class 1 as shown in fig. 16). By taking the following mea-
sures the distinction of other communication errors becomes possible:
• A (occasionally) decrease of the capacitive load (by taking off "green" slaves or
by shorten the net length) leads to the resumption of the critical slave, if an out-
sized large capacitive load is present.
• Often faulty capacity-rich slaves do not become a problem unless several cop-
ies of this faulty slave are used in the net simultaneously. If alternate removing
of some of these slaves leads to the resumption of other failed slaves they pre-
sumably poses an outsized entrance capacity.
• An AS-i bus termination or an AS-i tuner can compensate incorrect impedance
in some cases.
• In the trace the situation can be observed more exactly. Depending upon its po-
sition in the net, even the analyser cannot recognize individual telegrams any
more then.
7.3.6
Error by Configuration Deviation
In the configuration mode of the master, which is used particularly to build up the
AS-Interface net, each slave is taken up to communication. The tab "Configurati-
on", however, constantly permits an examination of the current configuration (plea-
se note that all configuration data are indicated only if the analyser has been
attached during a start up phase of the net).
In the "
Safety Operation Mode
" of the master (normal used with an installed faci-
lity) each incorrect configuration leads to a stop of communication with the affected
slaves and to a message "Configuration Errors" displayed on the master. Additio-
nally you find in the traffic light representation of the overview:
• Slaves temporary missing (or defective or blocked),
• Slaves with a correct address and a wrong configuration data
• Slaves with the wrong address (not configured slaves)
• Replaced slaves with address "0" which are not readdressed and taken up to
communication again.
In the first case the relevant slave appears red. The message "Config_error" is in-
dicated on the master additionally. The communication with this slave is interrup-
ted.
In the second and the third case the relevant slave appears grey: Communication
with this slave is not taken up by the master since the slave is not configured. A
previous log or the examination of the master data can give information about this.
Summary of Contents for as-interface ANALYSER 3RK1 904-3AB01
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