thingstodo
Member
A ControlLogix backplane is a communications network, its proper name is ControlBus, although universally accepted as "backplane"... Modules connected to the backplane "communicate" on that network, using CIP, at a mere 5 MB/s.
Adding a 100 MB/s Ethernet module to the chassis, and using it for remote I/O will not give you a faster data-rate than 5 MB/s, since the data ultimately has to travel across the 5 MB/s backplane.
And don't forget that any remote chassis backplane also runs at 5 MB/s.
Are you sure about those numbers?
Adding a 100 MB/s Ethernet module (or several) to the chassis still requires the information to flow from the L73 to the EN2T over the backplane.
I had 5 L73's in one 17 slot chassis producing/consuming 4 arrays of 100 32-bit dints each, every 20 ms, alongside 3 controlnets that scheduled to >80% bandwidth. The enbts were used for a programming interface. Plus a couple of Prosoft cards that transfer blocks of ... 400 registers? .. every 40 ms. I dropped the RPI for the produced/consumed to 5 ms for testing ... and I never ran out of bandwidth on the backplane. I would have guessed the backplane to be >50 MB/s. To service even a couple of EN2Ts plus a couple of controlnet ... maybe 200 MB/s?
If RA limited the bandwidth on the backplane to 5 MB/s. That would only service one Controlnet?