Re: Fwd: pulse train

[Paul <paul.corner-at-tesco.net>]

Hi Scot

The top pulse rate is limited by a number of factors - Type and size of 
stepper motors, the drivers (bipolar or unipolar) and the input voltage. Also 
another thing to affect performance is the motherboard chipset (onboard video 
sharing main memory is bad).
These points aside, I have had a Celeron 600 running with PERIOD set to 
16uSec which equates to a theroretical pulse limit of 31250Hz. An Athlon 1800 
ran at ~7uSec (71500Hz pulse rate), but this left precious little time to do 
anything else. Yet, even on the Athlon, I ended up setting PERIOD to 40uSec 
when tuning EMC for a Sherline mill.

The maximum pulse rate from a 667Mhz P3 is likely to be well above what can 
be used. To get some idea of the maximum pulse rate required, use the formula:

                 1
   ------------------------------
   2 X MAX_VELOCITY X INPUT_SCALE


Where MAX_VELOCITY is in inchess per Sec
and INPUT_SCALE is the steps per inch.


Regards, Paul.




On Sunday 15 Dec 2002 10:16 pm, Scot Rogers wrote:
> I'm getting ready to put my table motors and emc together and was curious
> about the pulse per second capabilities of emc with a Pentium III 667mhz or
> higher.  Is there any info avialable on my question?  I'm planning on using
> steppers in freqmod.  Unless there's things I should know that would push
> me other directions.