Different:
- EtherCAT is probably the first Ethernet network to achieve prominence that was designed from the ground up as a ring architecture.
- Messages move completely around the ring. When a message completes the cycle all nodes have been updated with the latest data from the Master.
- A massive amount of data can be transferred. Slave nodes simply look like a big chunk of memory to the Master.
Novel:
- Any node can be the terminal node in the ring. If there is a failure at the next node, a node will close the ring automatically.
- The ring technology allows node propagation to be measured through individual nodes as the propagation through the network can be measured for any node simply by removing it and comparing the propagation before and after.
Surprising
- Nodes can be built with up to 32 discrete I/O points without a CPU
- Time synchronization between slaves is better than 1uS. One slave (not the master) is designated as the time reference node.
- This is not a network you can share with your office net. EtherCAT as such a high utilization of the Ethernet bandwidth that it will take down your office network.