Re: EMC-programming request

EMC users,

I took the emc-16-Jul-1999 release off the FTP site since this was a
beta version for Tim Goldstein to test, and it's still not working. I'll
give future beta releases names like "melissa-virus.tgz" to keep
everyone off until the release works.

I'd like to gather as much information on backlash compensation as I
can. The algorithm works like this:

/* begin */
if (moving positive) then
comp_value = backlash / 2
else if (moving negative) then
comp_value = -backlash / 2
else
/* leave comp_value as is */
endif

comp_output = command_output + comp_value
/* end */

One variation of this sets the comp_value to 0 in the last else clause,
which moves the motor into the middle of the backlash range when motion
stops. This resulted in an extra motion in the reverse direction when a
move stopped, which I didn't like, but if there's a good reason for this
someone let me know.

--Fred