Re: Analog Spindle

[Jon Elson <elson-at-pico-systems.com>]

Kurtis Martineau wrote:

> Dave, and anyone interested in the emc interpeter,
>
> Please take a look a the following manual:
>
> http://www.isd.cme.nist.gov/personnel/kramer/publications.html#RS274NGC3
>
> Unless I am mistaken, it would appear that the emc interpeter is more
> complete than we using it.
> The S**** command for speed is ready to be used (I think) - just how can I
> direct it?

Yes, absolutely, the interpreter handles the S word, and sends an NML message
through to some level inside EMC.  And, some code has been written to pass
that along  to the STG-I card.  I don't know if it works now.  I suspect it DID

work at some time.  I will take a look at it in the BDI version I am working
with
right now, and see if I can get it to work with my new parallel port hardware.

>
> The other functions that I am interested in are also there.  Like clamping
> outputs at the end of motion to hold position when using brakes on larger
> machines.  The controller I took off clamped the X and Z axes after a
> configurable time delay, which kept the motors alot cooler when motion is
> not required.  I currently have the brakes wired through the software estop
> and use a seperate 120v e-stop cct (mushroom button, overtravel limit
> swtches, amp faults, etc) to disable the 3 phase power to the motion
> contactors.
>
> How can I configure the time delay before an axis is clamped and how can I
> direct it to a STGII output? Once I have a bit that will toggle to the
> outside world I can do the rest - It's the inside between the interpeter and
> the STGII card where I have a hard time.

Well, you are really going to have to write C code to do this, as EMC is not
going
to know anything about this.  Very few modern machines use this kind of
clamping.
It was common with one-axis CNC back in the 1960s, when a single axis drive
was switched among several axes.

It should not be necessary with modern motors and servo amps.

Jon