Re: BDI

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

Hey sorry for the bandwidth.  I didn't realize that I was posting my 
commercial message to the entire list.

Hi Dave (comments mixed in)

On Thursday 30 May 2002 10:39, Dave wrote:
> Hi,
>
> I'm looking to get EMC setup and running too.
>
> I took a look at the web site: http://www.yty.net/cnc/bdi.html
>
> It seems to only have 2.11 & 2.12 available.

There is one EMC relevant difference and that is a fix to the circle cutting 
problem that we created when we asked for full circle cutting.  This would 
not be a serious upgrade and we could put a copy of the RPM on the dropbox at 
linuxcnc.org.

> I actually don't mind setting everything up from scratch (I setup my old
> 486-33 as a firewall). I know I'll want to build EMC from source (that way
> I can make changes, if desired).

The BDI includes the sources and you can do a developer install that will 
provide all of the compilers needed for the project.  But there is nothing 
quite like a "roll your own" to help you understand how it all fits together. 
With what you know of Linux already, it should be no problem to do that as 
long as you have the time and the inclination.

> I have a 200 MHz Pentium Pro that I'd like to use to run EMC. It currently
> has a Voodoo 3 video card. I see Voodoo drivers available for Linux, so I
> should be able to get that part working.

I'm currently running my grizz mill with an overclocked 166 Gateway.  I think 
that it's running about 200 MHz or about 390 Bogomips.  I don't have any 
problem with the BDI 2+ series with it and can get about 35-40 ipm with 6k 
pulses per inch.  And I'm running all the Tcl/Tk stuff including tkio feeding 
an aux parport.

> What's the primary difference between the 2.14 version and the TNG version?
>
> The 2.12 version appears to based on the 2.2.x versions of the kernel. Is
> the TNG stuff based on the 2.4.x?
> I also see that RTLinux is up to version 3.1 and I've found some patches
> for 2.4.18.

You've got the essence of the difference.  If what you want to do is run a 
machine with that 200, I'd recommend the 2.12 or 2.14 rather than TNG.  If 
you do decide to use the 2.4 kernel, my leaning is toward rtai because I 
think that they will be much more likely to keep up at least for the near 
future.

> What is it about the TNG version that requires more horsepower (presumably
> the graphics stuff, like KDE?)

Yep.  Almost every package in there suffers a bit from bloat.  And it runs a 
lot more background tasks out of the box.  When you run the EMC, it doesn't 
suffer but your screens will a bit. 

> I have a copy of RedHat 6.0 that I used as the starting point for my
> firewall (I think it uses 2.2.5). So I guess my basic plan of attack would
> be:
>
> Install RedHat 6.0
> Upgrade the kernel to the latest 2.2.x version (or is there a particular
> 2.2 version that's better for EMC)
> Install RTLinux (should I use 2.x or is 3.1 OK?)
> Install EMC

There are some references in the existing handbook to compiling using the 2.2 
series of kernels.  I did them with Mandrake 7.0.  You might be able to get a 
path out of them for your own.  But the nature of both Linux and RTLinux have 
evolved quite a bit since then.  The BDI 2+ series uses the 2.2.18 kernel and 
RT 3.0.

> If required, I don't mind upgrading the motherboard to something more
> suitable either. I just thought I'd get some idea of what might work before
> I start.

I recently purchased a FIC ATX motherboard with one isa slot and a 800 MHz 
Via/Cyrix proc for less than $100.  That's my fastest box, stone age by now, 
but it is more than enough for Mandrake 8.2 with most everything running at 
the same time. 

Hope this helps.

Ray