Re: [CAD_CAM_EDM_DRO] EMC Encoders

Ethan Vos wrote:

> Good day all.
>
> I am planning to use EMC to control one of my machines but I need to figure out how to hook up the stepper encoders.
>
> Do I need an additional parallel port for the inputs, or do I need a special board.

You need a special board. There are a few options. The Servo-to-Go board
is really designed for servo systems, so it is not what you want.

The Dan Mauch DRO board plugs into ISA slots in a PC, although many no longer
have these slots. It is probably the cheapest way to go. I have designed a card
that connects to the parallel port, and reads the encoders if so equipped,
otherwise it counts step pulses, and generates the step pulses smoothly,
with timing hardware outside the PC. This looks a lot like a servo system to
the PC, as the computer tells the step rate generator what speed to move at.
It also has digital inputs and outputs for limit switches, spindle power, etc.
Unfortunately, this is not quite ready for sale, yet. I'm working on it hard,
though.

> Can anyone point me to some information about using encoders with EMC?

Here's Dan mauch's web page :
http://www.seanet.com/~dmauch/

I believe there is some info here :
http://www.linuxcnc.org/handbook/htoc.html
But I couldn't find it in the index.

There is a special version of either steppermod.o or freqmod.o to use the Dan Mauch
DRO card for feedback.

Jon