Re: BDI with DRO/Encoder Board

From: "David Kryskowski" <kryskowski.david@...>

Hey Dave. I'm an other but my comments are mixed in.

To Jon Elson ( & ALL):
<s>

>I compiled the latest version from linuxcnc.org. dro.h and dro.c had to
>be updated from the latest fixes at sourceforge. The install script is
>much improved and made life much easier. Running with smdromod.o is much
>slower than using the original BDI code. I am not sure what the problem
>is. It is really unusable when using the tk interface. The xwin interface
>is somewhat better and the mouse somewhat follows your hand movement. I
>did compare the .ini files and the timing parameters were the same. Could
>be compile optimizations but have not looked into it.

Sounds like something worse than compile optimization! There may have been
changes in other modules between the linuxcnc.org version and the latest
dro stuff. Perhaps a full download from sourceforge would be in order.

>Our machinist and I will be using the computer control for the first time
>tomorrow. We went over the interface together today and it seems pretty
>simple.

Good. It helps when a machinist says, "I can use that.."

>Finally since I can't use smdromod.o for week what is the best
>motordriver to use for my appication? Is it stepmod.o or freqmod.o? I have
>seen the new ppm code that you wrote at sourceforge (pulse position
>modulation?). Should we give that a go?

The now archaic name PPMC was parallel port motion control. It is the set
of software to run Jon's EPP card set. The stepper card that he ran at
NAMES was very nice! Don't know if it is ready yet though.

You could run steppermod or freqmod. Freqmod needs a faster PC but
produces a more regular pulse train.

HTH

Ray