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Sercos-III-Information
TR-Electronic GmbH 2013, All Rights Reserved
Printed in the Federal Republic of Germany
Page 72 of 103
TR - ECE - BA - DGB - 0105 - 03
08/31/2017
3.5 Sercos-III-Communication phases
The initialization is divided into five communication phases (CP0-CP4) and the
NRT state:
After the power was switched on and internal checks are completed and error-
free, the NRT-state is present. In this state only IP protocols can be
transferred.
With the transmission of the first Master Data Telegram MDT0 the master
activates the communication phase CP0. Furthermore only the IP channel is
active in this state. CP0 is used for recognizing the participating slaves.
CP1 is used to configure the slave devices for NRT-communication and is
present after the master has received 100 AT0-telegrams of identical contents.
In this status the service channel is initialized only, but is not activated.
CP2 is used to configure the slave devices for NRT-communication and for
parameter settings about the service channel.
CP3 is used to further configure the slave devices. The cyclical communication
is already running but is not evaluated yet.
In CP4 the initialization process is complete and the Sercos-III-Network is in
operation.
Figure 4: Communication phase state machine [Source: Sercos International e.V.]