On Sat, 27 Dec 2014 02:41:50 +0100 (CET)
karl@??? wrote:

> Gordon:
> > A while ago, I started trying to get a chroot Debian environment
> > set up on Gentoo, and ran into troubles. [...]
>
> It's ususally not a problem doing a chroot debian on debian using
> debootstrap. The issues that you need to be aware of are to mount
> /proc and any needed fs in the chroot, and that listening network
> sockets can collide (you can't run sshd booth in the normal / and
> in the chroot unless you use separet port numbers).

I had made a chroot on Debian, to compile OpenWRT (which is nominally
Debian). That was find, doing this on Gentoo was strange. I hadn't
even gotten close to /proc stuff (I believe).

> > Part of what I need to set up soonish, is CNC abilities. LinuxCNC
> > exists, although the preferred platform is a LTS *buntu. I want to
> > work with amd64 CPUs, and it looks like having Arduino or
> > BeagleBoard microcontrollers is the cheap way to interface
> > EMC2/LinuxCNC to
> [...]
>
> Can't you use a parallell port?

Before I started with Linux, I was using QNX-2.x. Among other things,
I had interfaced the parallel port to miscellaneous nuclear counting
equipment. Eventually, we moved to a high current digital I/O board.
I don't remember if the DIO had optical isolation, or we added optical
isolation.

It just looks like going microcontroller is going to make for a better
hardware setup, based on what I did in the past.

> > I haven't looked at any of the code for ChronOS, but instead of
> > using the soft real-time patch that *buntu uses (and most people,
> > and I am not sure it is the soft patch), the VirginiaTech group did
> > use the hard real-time preempt patch.
>
> Don't linuxcnc use rtai (https://www.rtai.org/) ?

I thought they were the same, but I will look some more. :-)

> > In any event, I may be able to come up with a Devuan to the two
> > different real-time CNC worlds. Something to do when I get tired of
> > trying to electronics again. Plumbing is sooo much easier to
> > solder.
>
> http://article.gmane.org/gmane.linux.distributions.emc.user/52401
> talks about linuxcnc on debian wheezy, perhaps it can be of help.
>
> Regards,
> /Karl Hammar

Thanks.

Looking at VMs via QEMU, it seems my kernel is missing some
capability. So, I am starting by downloading a newer kernel, playing
make menuconfig (or the genkernel version) again, and moving on from
there. As I just started with Gentoo this year, I only have the 1
working kernel, and I liked to have 2 different kernels when I was
running Debian.

Gord