Re: EMC and BDI install

[Ray <rehenry-at-up.net>]

On Friday 14 December 2001 08:57 am, you wrote:
> Guys,
>
>  I have few comments on EMC and the BDI image, please dont get me
> wrong...

There are enough good folk on this list who struggle with English or 
American to encourage all of us to bear with each other.

<s>
>  I recently downloaded the bdi image with the bdiemc-2.11-01.img and I
> am very impressed with
> the ease of installation, it picked out the video and monitor hw,
> etc,etc,etc. excellent
> job.
>
> However, I would like to know few things related to both EMC and the
> BDI image.
>
> regarding EMC, How is Backlash compensated? I have 0.008" Backlash on
> my X axis and it
> does not compensate it at all, every commanded move I issue, is done
> very well but the
> first. I have both used 0.02 mm and 0.008" values and it does not seem
> to compensate it
> at all, the input value is 5000 for each axis.

There has been some discussion of backlash problems but I don't thin all 
of the issues have been resolved.  Joel Jacobs demonstrated some 
interesting problems at NAMES last year.  It would compensate but not 
consistently or correctly.  It would also consistently move the home 
position with each subsequent home command.

> regarding the BDI, unless was it done on Feb, 11th? or Nov 2nd? the ftp
> site lists the file
> as being modified Dec, 04th. this question is related to the following
> issue.

I think that this date somehow crept into the sourceforge stuff.  I know 
that it caused several of us to wonder about what time our computers were 
referring to. 

> as I said, I just downloaded and installed it, also installed the
> developer's version
> (different partition) but when I tryied to rebuild it, just issued the
> /usr/local/compile
> command, it would not build, I had to edit the Makefile.inc and the
> generic.def files in
> /usr/local/emc/src and /usr/local/rcslib/etc directories.

Would you be able to make a list of these changes, the file names and line 
numbers that they reference.  Then someone with more ability to read make 
files can sort the problems out.

There is some effort afoot to convert the code to an automake routine.  
Perhaps that effort would be a place where you gifts could help a lot.

> Also I found that the sources are not quite up to date to the CVS
> repository, I understand
> that there must be some lag, between image builds and the CVS files
> also I belive this is
> not a full time work, but it seems quite a large gap, since the
> emcstepmot.c's modification
> history does not reflect the 2001 changes logged in the file from the
> current CVS.

You are very right here.  Paul does all that he can but there are enough 
issues with building the BDI beyond the EMC and RCSLIB code that keep him 
more than busy.  As a result his EMC snapshot does not aways reflect the 
latest code in the repository.  Here again, perhaps someone who is willing 
to keep a compile of the SourceForge code current under the BDI would be 
helpful.  

> For my particular situation, I need to modify this file or the emcmot.c
> file, to be able to
> use the existing driver hw, which is slow, but works fine for our
> particular app.

Do you have a brief description of the hardware, and is your hack 
something that would be of value to include in the code base itself for 
others to use as well? 

I think what I am thinking in response to your post of these issues, and 
they are all good points to make, is that you should consider signing up 
at sourceforge to be an EMC developer.  Your knowledge of makefiles would 
be a terrific addition.  And you would read and write a common language 
with many of the developers.  Setting up an account there is free.  The 
most difficult task is SSH.   If you are not familiar with it, the hardest 
part will be reading my web page about becoming a developer in the 
linuxcnc.org/handbook. 

> If the particular BDI image, I mentioned in the message, is not the
> current one, please let me know which is the current, if there is a way
> to download a patch, Iwould greatly appreciate, someone leting me know
> about it.

I'm sure that it is the latest BDI available.  BDI will never be the 
latest EMC available.  EMC at sourceforge is evolving fast enough that it 
is difficult for developers to keep up.  This is the reason that I have 
placed a couple of my own compiles of the EMC under the BDI distribution 
in the dropbox at linuxcnc.org.  Some key BDI players have very slow 
internet connections on the machines that we do the work on and are not 
able to deal with the whole image at once.  Perhaps in time, the whole BDI 
will become a sourceforge group effort.  

Ray