RE: [CAD_CAM_EDM_DRO] emc input scale reboots

> -----Original Message-----
> I'm running EMC Linux 2.4.18rtai on a 166Mhz bix ( cuz my new
> box was faster but couldn't run this kernel, and the new UniSTuttgart
> bundle didnt include Steppermod or source :-( )
> Anyways, I got it up and moving my ShopTask with 650 ozinch
> steppers from Tim. I went to et the scaling factors, and laid
> a dial vernier on the X way, Zeroed the machine and moved in
> 0.1" on the dial
> vernier. Then I got the reading from the DRO, it was 2", so I went
> back and checked, make the machine move 1 step using testppt,
> ok, it's true I got "half tenth' steps, 1 step is 0.00005".
> No big deal, just a number, so enter Input_Scale as 20000,
> right? it takes 20,000 steps to make 1 inch? well the machine
> rebooted just before the TK_EMC screen appeared. Many times.
> I changed the number to 10,000 and got a very sluggish, but
> working system that gives me 1/2 scale output. What to do?
>
> BTW: thanks to the EMC guys for making such a nice package. I
> see a lot of rants, and then I whine, but they did a great job!
>
> regards, TomP

Try reducing the MAX_VELOCITY in each individual axis section and in the
TRAJ section to 1/2 to 1/3 of whatever you have. Then you should be able
to increase the steps per unit to the 20,000 you need. Not sure if this
is correct technically, but EMC with freqmod.o seems to load the
processor based upon the product of steps per unit x max velocity. If
you get it too high it croaks. So, by dropping your max velocity you can
crank up the steps per unit. Not sure what you have there, but 60ipm is
plenty on a Shoptask so a setting of 1 in the individual axis max
velocity and something like 1.5 in the traj will work just fine. Now it
may still be too much for a 166 in which case you need to reduce the max
velocity to a usable value for that system. I would suggest you consider
a faster computer.

Tim
[Denver, CO]
Sherline & Taig products at Deep Discount
Mach1 & DeskCNC with credit card ordering
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