Re: [CAD_CAM_EDM_DRO] study, study, study

Weyland wrote:

> From: "Tim Goldstein" <timg@...>
>
> > Am I hearing a volunteer to help with the creation of a good EMC manual???
> > That is how much of what is available came to be.
>
> Tim, if you think *anyone* could learn *anything* from my
> hack & slash full imersion method of learning, you're
> more than welcome to use anything I come up with~!
> Being this new though, I wouldn't know what *was*
> good info if it slapped me in the face.
>
> Honestly though, if you think something is useable, I'd be happy to help.
>
> > To use encoders closed loop with steppers get a Mauch/Kulaga DRO card from
> > Camtronics and then use smdromod.o in EMC once the code is fixed.
>
> <heavy sigh>
> *Another* word to go look up...
> What's "smdromod.o"?
> Does the name stand for something?

Umm, sort of. DRO is for Digital Read Out, which is what the Dan Mauch/
Tom Kulaga board was originally designed for. SM, I think, is from
Steppermod, as it contains most of what steppermod does in open-loop,
but this one does it closed-loop. mod, which shows up in all the
real-time components of the EMC package, refers to 'kernel modules'.
kernel modules were originally intended to work as 'loadable device
drivers', essentially extensions to the Linux kernel that could be
installed and removed at will. The real time patch for Linux uses the
same mechanism to get these pieces cleanly in and out of system
memory where Linux knows to not bother them, and makes address
linkages available to the RT scheduler, which can give them control
of the machine when needed. So, EMC contains a number of
files with names that are xxxxmod.o, that are used for different
types of motion control hardware. steppermod.o is a simple
stepper driver that uses the parallel port to drive up to 4 axes.
freqmod.o is a somewhat more advanced version that produces
somewhat smoother step pulses. stgmod.o interfaces with the
Servo-to-Go card for servo control of up to 4 axes. stg8mod.o
controls up to 6 motion axes, and leaves the possibility of having
2 extra encoders do something like jog dials, although that hasn't
been implemented in EMC. stg2mod.o is the equivalent for the
newer version of the STG card. Now there is also ppmcmod.o
to use my parallel port motion control hardware, and soon ppmcratemod.o
to use my parallel port stepper rate generator. You would onyl
use one of these at a time in most cases.

Jon