Realtime of Hardware & Network- EtherCAT

Unique

    Ø    Protocol Hardware integration in the slave

    Ø    Direct memory access to the network controller in the master

Independent

    Ø    Dependent on its Own hardware and protocol stacks

    Ø    Independent from the CPU performance or software implementation.

The update time

    Ø    256 I/Os 11us

    Ø    1000 I/Os 30 µs

    Ø    1486B process data 300 µs, equivalent to 12000 DI & DO.

EtherCAT Instead of PCI

■  For PCI

    Ø    more IOs need more Slots

    Ø    The physical size of Industrial PCs restraints its IO scale

■  For EtherCat

 Ø    Controller Only has CPU and Common Ehternet interface

 Ø    Controller can be smaller

 Ø    Decentralized IO,axes and control units,complex system,geteways and other communication interface can be easily used

Realtime of Software&OS- QNX ■Multiple concurrent scheduling algorithms   FIFO, Round Robin, Sporadic   ■Prioritized pre-emptable threads   256 priority levels Fully pre-emptable and deterministic kernel   ■Prioritized and nested interrupts   Interrupt handlers can schedule a user thread or run custom interrupt code