Lenze I/O system 1000 System Manual - Manual (Page 392)

PROFIBUS communication
Communication
Communication medium
9
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392 EDSIO1000 EN 7.0
Services for the acyclic parameter data transfer
Data transfer between DPM 1 and slaves
The connection is established by DPM 1 via the MS1 channel. The connection to the slave
can only be established by the master that has parameterised and configured the slave.
Service Description
Read The master reads a data block from the slave.
Write The master writes a data block to the slave.
Alarm The slave transmits an alarm message to the master. The master acknowledges
receipt. To prevent alarm messages from being overwritten, the slave can only
transmit a new alarm message if it has received the acknowledgement.
Alarm_Acknowledge The master transmits an acknowledgement to the slave, confirming that it has
received an alarm message.
Status The slave transmits a status message to the master. The master does not
acknowledge receipt.
Data transfer between DPM 2 and slaves
The connection is established by DPM 2 via the MS1 channel using the "Initiate" service.
One slave can maintain several active connections at the same time. The number of
connections is limited depending on the resources available in the slave.
Service Description
Initiate / Abort Establishing or terminating a connection for the acyclic data transfer between
DPM 2 and a slave.
Read The master reads a data block from the slave.
Write The master writes a data block to the slave.
Data_Transport The master writes user−specific data (defined in profiles) to the slave and, if
required, it reads data from the slave in the same cycle.
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Note!
For further information on the services and communication with DP−V0 and
DP−V1, refer to standard IEC 61158.
9.3.4 Communication medium
ƒ The communication medium is an RS485 interface.
ƒ The bus can be configured as line or tree topology.
ƒ The bus structure under RS485 enables the reactionless connection and
disconnection of stations as well as the gradual commissioning of the system.
Subsequent enhancements do not affect the stations already in operation. It is
automatically detected whether a node has failed or just been connected to the
mains.
ƒ The PROFIBUS bus coupler is provided with a 9−pole Sub−D socket for connecting
them to the bus.