The Hilscher netX chips are interesting (e.g. the large amount of SRAM, DRAM support, multi-protocol support, IEEE-1588 support, hub/switch support), but definitely have their issues such as only BGA packages, small cache (a 200MHz ARM9 with a small cache is definitely bandwidth limited), no floating point, and lousy peripherals (ADC and PWM are pretty limited compared to motion-oriented DSPs and Cortex-M3s). The netX approach is roughly similar to Freescale’s PowerQUICC MCUs, especially the MPC8360 (but the 8360 is substantially more capable (e.g. gigabit Ethernet) and complex; pricing might be about the same as the netX 500).

The netX chips aren’t well suited for small companies, and would require a redesign for many vendors (e.g. Cognex Insight uses PowerPC IIRC), which isn’t likely to happen. BTW, the open source stack for Ethernet PowerLink (thanks, Systec) should also make it easier to add real time protocols.

I still suspect that most manufacturers won’t be adding real time protocol support until a lot of their customers ask for it. I know regular Ethernet is quite fine for tasks such as communicating machine vision results from smart cameras to robots. Also, I don’t think multi-protocol support will become that common; I think most companies will pick one or two to support.

I could easily expand this into a full post, but unfortunately right now I’ve got other tasks to do.

As far as I know Ethernet Powerlink doesn’t use IEEE 1588.

I think the reason for the difference you’re seeing comes down to the fact that many customers who have a lot of I/O don’t need the quick cycle times and low jitter you can get with real-time industrial Ethernet. For applications with a lot of I/O and low realtime requirements, Modbus/TCP is a great solution because it’s very cheap to implement and widely available.

My guess is that you’ll see more and more vendors of slave devices supporting a bunch of common real time Ethernet protocols. Adding real time Ethernet to a product used to be a big development effort, but you’re starting to see products like the netX chip from Hilscher (http://www.hilscher.com/netx.html) that make it a lot easier.

Companies like B&R are already taking this approach with their I/O devices (see for example http://www.br-automation.com/cps/rde/xchg/br-productcatalogue/hs.xsl/products_110129_ENG_HTML.htm).