Connecting to a CNC machine, pros and cons of USB vs PP vs Ethernet etc.

[magicniner]

Ethernet really isn't a natural partner for realtime stuff

20 years of 1st to 3rd line IT support and development work in industrial control for Blue Chips strongly suggests otherwise to me.
Have you read up on the error-checking and packet resending features of the Ethernet Protocol?
Where routers are involved information can travel several different routes and still be resolved at the destination, this is why the images which you view in your internet browser show so few errors.
Ethernet is not erratic (or even irratic) it's a very robust communication protocol, if you'd levelled your accusation against Token Ring then you may have had a leg to stand on!
Regards,
Nick

[JAZZCNC]

then you may have had a leg to stand on!

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