DeviceNet

Hi Everyone,

I setting up a DCS using AB micrologix 1500 and deviceNet. I know deviceNet utilizes the CAN protocol. I am wondering if anybody knows if I can set the arbitration field(determines who wins the collision)or if devicenet just randonly sets this field.

Thomas Franklin

On DeviceNet, bus access arbitration depends on the MAC ID and the Group Number of the message.

It is not random.

This is handled automatically by the firmware of the DeviceNet nodes themselves. A PLC programmer has no need and no tools to alter the bus access arbitration mechanism, other than changing the type of message (Polled, COS, Cyclic, Strobe, Explicit), which changes the message Group Number.

Thanks Ken.