Re: [CAD_CAM_EDM_DRO] black box specs

GW wrote:

> <unlurk>
>
> Jeff, it's not as bad as you think.
>
> Jon, with the exception of ATM (and Allen-Bradley's ControlNet), few
> networks are deterministic. All are described in probabilistic.
> I've worked with _many_ fieldbus type I/O system. Ethernet is
> becoming very popular because of it price, ease of use, distances,
> reliability, etc.. Probability is based on loading, network speed, etc..
> Do a quick lookup of industrial Ethernet, you may be surprised at what
> is being done with it in real-time control environments.

Yes, sure, but my Linux-EMC system talks to the motion control
stuff every 1.0 mS (and could do it more, if I needed it to). If you
want to have all the motion control in the external box, then it
can work fine, but if the PC is inside the 'loop' (especially with
servos and encoders) then you can't have fifos, non-deterministic
communications between the PC and the motion logic, etc.

Jon