Re: EMC-BDI 2.04

Carl

I'm going to back up just a bit in this explanation so that folk new to the
list will know better what we are talking about.

The Brain Dead Install is a complete set of motion control software. It is
built on the Linux operating system and some real time extensions to the
Linux kernel. For motion control it uses the Enhanced Machine Controller
software written in part by the National Institute of Standards and
Technology in the US.

The Linux and real time extensions allow you to setup a complete PC operating
system. They include text and graphical interfaces that allow your PC to act
a bit like both a DOS and a MS-Windows(tm) computer. They also allow you to
specify fairly specific times and timing for the input and output of signals.
The BDI includes common networking and printing software (BDI 2.04 needs a
small download from www.linuxcnc.org) and will allow you to play games and
surf the net.

The EMC motion control system is a rather broad based set of software that
will control steppers from a parport or an external card, will control
steppers with encoder feedback using an auxiliary board from Dan Mauch, and
will run full servo systems using one of several encoder and analog out
boards and outboard systems. It will control up to six motors in it's
present state and can make allowance for Cartesian machines (axes 90 degrees
to each other and rotations about them), Stewart Platforms (hexapods), Puma
like robots, and vehicles. With it you can also compensate for lead-screw
error, some small backlash, and operting temperature. I like to refer to the
specific configuration of the EMC as a personality, and there are a lot of
them that are possible.

The birth of the BDI is in a thread on CAD_CAM_EDM_DRO@yahoogroups.com during
it's early years. During that thread, many thought that the EMC was way to
hard to install for the average shop guy. The challenge to produce an easy
to install version of the above software was taken up by Paul Corner in
England and the BDI 2.04 was the first public release. It was announced
April 1, 2001 and showed at NAMES that year and shipped soon after. It is
based on "open source" software from Red Hat Linux distributors.

As with any stack of software, bugs were found once it came into public
release. The biggest shortfall of 2.04 is that there were a number of
computers, video chipsets, and monitors that were not adequately probed
during startup. To setup the BDI you only need to make your PC boot from
CDROM or make a boot floppy from files and programs that are contained on the
CD. You will know if the 2.04 is going to work for you soon after you boot
it. If you do not see a display of a milling machine (Dan Falck's RF-45) on
a green background, the BDI's probing routine has some issues with the box
you want to put it on. If the screen goes black and stays that way for a
long time your driver card has not been recognized at all. At this point you
can simply turn the PC off and your old system will reboot after you fix the
boot source in the bios.

You may be able to install it and get it working satisfactorily even if the
BDI goes into text mode and does not show the milling machine. Arrow, tab,
spacebar, and enter keys will allow you to navigate the screens. You will be
able to test video chipset drivers and monitors at one point during the
install. On most of these kinds of installs I have been able to find a
driver and monitor combination that will allow for graphical viewing. Linux
and unix users call this the X-windows interface. You will be able to use
any one of several display managers once this is correctly set up.

The BDI 2+ will work on most older PC's. I have installed and run it
successfully on 166 Mhz processors with 32 Meg RAM and with hard drives as
small as 420 Meg for a workstation version. The developer install requires
about 1.2 Gig. You will need more processor power if you plan to run
freqmod. Freqmod is one of those personality things. You will need faster
processors if you want a lot of speed or accuracy from your CNC.

There are also a couple of bugs in the EMC code on the 2.04. One has to do
with an occasional system crash when you first start a motion. If you get
past homing then it will run fine. If you don't you may get a black screen
of death, a reboot, or a general lack of response to mouse and keyboard
input. There is also a small problem with the g-code interpreter that
sometimes misses full circles when they are contained in a single block of
code.

These problems have all been addressed in the current BDI 2.14 release. A
lot of other stuff has also been added to it. The North American price is
still $10.00 and that includes s&h. Contact me directly if you are
interested in one. This release is also available for download from Henkka's
site in Finland. www.yty.net/cnc/bdi.html. It is a large file.

Now to muddy the waters a bit, Paul released a new version at NAMES this
year. This is the BDI-TNG (The Next Generation) which uses a rather full, 2
disk version of Red Hat 7.2. There are a lot of nice programs that run with
this release. This release also uses a different set of real time extenisons
from the rtai organization. The TNG requires quite a bit more speed from the
PC and a harddrive in the three or more gig range. The TNG should be
considered experimental or close to the bleeding edge. The North American
cost is $30.00 and includes s&h.

Hope this helps

RayH -- U.P. Michigan

>    From: "carlcnc" <carlcnc@...>
> I received BDI 2.04 last winter but never loaded it,
> I was waondering what release is latest, can I dnload patch/upgrade
> files from site?