Re: Base Task Period

[Jon Elson <elson-at-pico-systems.com>]

Hassan Rabe wrote:

>H ello all,
>I have a similar question like the one Kurtis just asked but with no
>card...am using stepper motors, i reviewed the emc handbook. and there is a
>value for the period of 0.00005 which is
>good for a P 150 MHz, am using a PIII 667 MHz, but when I changed the value
>to 0.00001 ...the computer stoped responding.
>
Of course, you were asking for 100,000 interrupts a second for the step 
generation task.

>am using stepper driver gecko 201...and I tested the machine on a function
>generator..the driver can handle a 10 KHz rate
>but I cant get the computer to even get close to halfe that rate.
>  
>
What is the max velocity and INPUT_SCALE and OUTPUT_SCALE settings in the
.ini file?  These have to be set to certain values for the step rates 
you want to generate.
A PERIOD setting of .00005 is 50 uS, or 20,000 per second.  This should 
be sufficient
for getting 10,000 steps/second, but the jump from 6667 to 10,000 
steps/second is
a big jump.  Are you using steppermod.o or freqmod.o ?  steppermod.o can 
go a little
faster than freqmod.o, but freqmod.o generates a smoother pulse train.

Jon