Beckhoff FC3101, Documentation

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FC310x as master
FC3101 and FC3102 50 Version: 3.0
Max-Retry-Limit : The Max-Retry-Limit specifies how often a telegram should be repeated, if the device
addressed does not answer. The minimum value should be 1, so that, in case of an error, there will be at
least one repeat for acyclic telegrams (see the
Error Reactions [
}
16] chapter).
Max-Retry-Limit (DX) : Since the Data_Exchange telegram is repeated cyclically, a value of 0 could be used
for the repetition of the Data_Exchange telegram here, in order to keep the cycle relatively constant in
equidistant mode, even if there is no response from a device. However, in this case it would make sense to
set the
Features [ } 59] tab for the box such that lack of response of the slave would not lead to DATA EXCH
being exited. The fact that a device has not responded is apparent from DpState [ } 25] , which would not be
equal 0 for one cycle (see the Error Reactions [ } 16] chapter).
HSA : The HSA specifies the highest active address up to which the GAP update is carried out (assuming it
is active).
Min. Slave-Int. : The MinSlaveInterval indicates the minimum cycle time with which the DP StartUp telegrams
are sent the DP slaves (it is determined from the settings found in the GSD file).
PROFIBUS Mode : This is where the selection is made between master [ } 10] functionality (the default
setting) and slave [ } 64] functionality.
Redundancy-Mode : Redundancy mode can be set here for the DP master. In that case all that it does is to
listen to the bus (see the Master Redundancy [ } 38] chapter).
GAP Update : The GAP update asks all stations up to HSA at intervals to confirm their presence. It can be
en/disabled. The GAP update is relevant only for multi-master operation. In single master operation it
increases PROFIBUS cycle jitter and is therefore switched off by default.
Optimize bus parameters: This is used to set the optimized bus parameters.
Default bus parameters: This is used to set the default bus parameters.