2 data transfer axis bus, 1 topologies, 2 transfer mechanisms – Lenze 8400 TopLine User Manual

Page 838: Topologies, Transfer mechanisms, 14 axis bus

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14

Axis bus

14.2

Data transfer axis bus

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Lenze · 8400 TopLine · Reference manual · DMS 6.0 EN · 06/2014 · TD05/TD14

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14.2

Data transfer axis bus

The data transfer axis bus is based on isolated CAN physics.

• Max. 62 nodes are supported at the bus (1 master and max. 61 slaves).
• The baud rate is permanently set to 500 kbits.
• Transfer clock = 1 ms

14.2.1

Topologies

There are generally two different topologies for an interconnected operation:

A. All nodes of the network are connected to the higher-level master control via MCI module and

the respective fieldbus.

• The axes can exchange data via the axis bus.
• Moreover, the CAN bus is available.
• For synchronous fieldbuses as e.g. EtherCAT, synchronicity of all axes towards the EtherCAT

fieldbus is achieved by selecting "MCI" as sync source for the axis bus master. The

synchronisation of the slaves on the EtherCAT side has to be switched off then.

B. Only the axis bus master of the network is connected to the higher-level master control via MCI

module and the respective fieldbus.

• For cost reasons, this topology only makes sense if only few information has to be transferred

from the master control to the network.

In both cases, the axes can exchange data via the axis bus and the CAN bus is available in addition.

14.2.2

Transfer mechanisms

The axis bus supports three different transfer mechanisms simultaneously according to the

following methodology:

• "@all": Data transfer from master to all slaves

• A data packet is sent from the master to all slaves in the transmission cycle.
• Application: Data distribution according to line topology
• Cycle time = transmission cycle = 1 ms (at baud rate = 500 kbits)

• "cas": Data transfer from node to node (cascade)

• In the first transmission cycle, a data packet is sent from master to slave 1, in the next

transmission cycle from slave 1 to slave 2, etc.

• Application: Data distribution according to cascade topology
• Cycle time = transmission cycle * no. of slaves+1

• "@sel": Data transfer from master to a slave

• A data packet is sent from the master to one selected slave in the transmission cycle.
• More options: Send to no slave, send to all slaves, and read one selected slave.
• Application: Data distribution according to line topology for controlling one single node.
• Cycle time = transmission cycle

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