Re: [CAD_CAM_EDM_DRO] EMC and new Redhat.

[Fred Proctor <proctor-at-cme.nist.gov>]

EMC Folks,

Ian Wright wrote:

> I'm a little confused! I was looking at the new release of EMC and
> downloaded it and the Beta11 version of RTlinux and then realised that I
> don't have a copy of the right kernel.
...
> Can anyone help and tell me whether
> either of the versions of RedHat I have are any use or, if not, what I need
> to download and from where? Thanks.

Will and I just ran some tests of the EMC on the latest version of Red
Hat Linux. There is a bug in the Linux "gettimeofday" function that
messes up the clock and slows down processes that call it. We're looking
into this with the Linux and RT Linux people. We worked around it in all
components except the xemc. However, the Tcl/Tk-based GUI is OK and it's
ready to be tested, so the xemc will soon be obsolete.

I don't recommend going to Red Hat 6.0 or 6.1 yet, but if you want to,
it can work. You'll need to wait until we get a clean and working
release, which should be after the weekend. Here's the summary:

1. Get a copy of Red Hat Linux 6.0 or 6.1. We got 6.1 off a mirror site.
It's about 600 MB, so don't try this through a modem. Buy a CD instead.

2. Get a copy of the "pristine" Linux source tree, version 2.2.13, from
www.kernel.org. Red Hat makes some small changes to the Linux source
tree in their distributions that cause the real-time patch to fail. The
source tree is about 15 MB.

3. The latest real-time patch is beta16, aka RT Linux 2.0. If you go to
the RT Linux home page, www.rtlinux.org/~rtlinux, and go to the FSM Labs
link, you can get this patch. Note that it works with Linux kernel
2.2.13.

4. Install the pristine sources, patch them as usual, and run the
examples.

5. Get the soon-to-be-released EMC for Linux 2.2 and test it out.

--Fred