[Bdi4emc-help] RE: X-Axis Display Problem

Fri Dec 1 16:56:02 CET 2006

Hello Paul,

*On Sunday 26 November 2006 16:37, elnerdo at cox.net wrote:
*> 20,000 counts per revolution is in fact pretty high for an encoder. The
*> "latest thing" however is the new sin/cos encoders which output counts in
*> the millions.
*
*The sin/cos encoder referred to in the article only has 1024 "periods" per
*rev. The sine waves are then interpolated to produce the 4M discrete counts
*with the aid of a dedicated DSP - Presumably, correction tables are
*programmed in to reduce cyclic errors and phase variations.
*
*> I originally thought the video card might be the problem source so I
*> replaced it last week (and lowered the period to .0001) but the problem
*> still remains.
*
*Unlikely unless it shares system RAM and/or uses proprietory closed source
*drivers
*
*> My next step is to make an attempt at recompiling without the debounce
*> code.  I have *some programming experience but a duffer's guide on this
*> would be great!  Really, any instructions or recommended reading you
*could
*> suggest would be appreciated.
*
*First stage is to install the tools and libraries using the command:
*
* apt-get build-dep emc

When I enter this command I get the following message:

Package rtai-headers is a virtual package provided by:
  rtai-dev-2.6.16.18-rtai 3.3-4+2
  rtai-dev-2.6.16.20-rtai 3.3-5+1
  rtai-dev-2.6.16-rtai 1
  rtai-dev-2.6.12.6-rtai 2
You should explicitly select one to install.

I know I need to include some additional information in get-build command,
but am not sure how to include it, can you help me out?

*Then "apt-get source emc" will download and extract the sources to the
*current
*directory. Run configure in src/ and add -DSIMULATED_MOTORS to the RTFLAGS
*line in src/Makefile.inc - A `make modules_install` as root will compile
*the
*low level module where the "position debounce" takes place - We don't need
*to
*worry about recompiling & installing any of the user space parts..
*
*
Thanks,

Craig