Re: [CAD_CAM_EDM_DRO] re:EMC

Anne Ogborn wrote:

> Never mind - the LinuxCNC.org site has a sane description of it.
>
> Despite 20 years in the software biz,
>
> "The Enhanced Machine Controller (EMC) program is a NIST effort to
> develop and validate
> a specification for interfaces to open architecture controllers."
>
> is still utter nonsense. To parse this -
>
> The Enhanced Machine Controller (EMC) program <-- EMC
>
> is a NIST effort <-- that's in English already
>
> to develop and validate a specification for interfaces <-- to make
> some software.
>
> to open architecture <-- we're gonna make it public
>
> controllers <-- could be darn near anything.

The first part is OK, the spec for interfaces part makes sense if you
know the
whole history, but tells the newcomer absolutely nothing.

What EMC is, now, is a program that runs under the RT-Linux operating
system,
takes in RS-274 commands and produces the motions expected of a machine
tool as commanded by the RS-274 commands. It supports stepper motors
both with and without encoder feedback, as well as servo systems.
It has several user interfaces (screen presentations) that work in a
character
cell terminal window, directly in X-windows, or through a
user-configurable
Tk/Tcl script in X-windows. The latter is the most advanced.

It supports a very wide variety of RS-274 commands, accepts programs of
arbitrarily large size, executes fairly quickly (although there is room
for improvement
there), and runs VERY reliably.

Linux provides networking services, so cutting programs can be sent by
network
from a CAD computer to the CNC computer. The X-windows environment
allows you to use other system services, like editors, calculators, etc.

while the machine is cutting materials, without interference.

Jon