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

[Jess]

There is no respect for experience it seems.

I respect experience. What has seemingly confused you is that I believe that respecting experience means you respect both what it tells you and what it doesn't.

"Knowledge|" without experience is just a collection of facts or suggestions, from here and there.

The collorary to that is: "Experience" without "Knowledge" is just half truths and old wives tales. You need both of them.

I'd have liked to present a more continuous narrative, but that's just not possible when the topic is getting changed enough times that we somehow got from the relative sophistication of ethernet and USB controllers to talking about connecting to a machine with a parallel port CANbus adaptor!

and then upgraded to Ethernet controllers. See Galil for example. Even cheap controllers have done the same. So there must be a reason for that.

Simple; the cost of doing it compared with the profit of doing it.

With the integration level of modern microcontrollers, an Ethernet port costs about the same to put on a board as a properly isolated USB port. Given there's also a willingness to pay a small premium for Ethernet it's not surprise that things are moving that way.

I am half expecting soon to hear that RP is better than ball screw and that HD alu profile gantry is stronger than steel one..

Don't worry, I'm not going to tell you to use coat hangers as rails for your X axis!

...I just wish people had done me the same courtesy on this topic. Especially given that later posts have now repeatedly confirmed what I've been getting shouted down for saying is correct!