invDistPerCycle works?

[gonzalo]

Hi Tom,

I am triying to calibrate the movement for my setup and I see in the manual the variable invDistPerCycle to do that. I have a regular 1.8º/step motor with KSTEP and I want my units in degres. Then following the example1 of the manual:

Example #1 : A mechanism moves 0.001" for each full step of a step motorIt is desired for commanded distance to be in inches.
Result: One Cycle = 4 full steps = 0.004",Thus InvDistPerCycle = 1.0/0.004 = 250.0 (cycles/inch) Commanding a move of 1.00 will generate 250 sine waves, or the equivalent of 1000 full steps, or one inch of movement..

Then I shoul do like that:

the motor moves 1.8º/16=0.1125º (due the KSTEP microstep) for each full step of a step motor It is desired for commanded distance to be in degrees.
Result: One Cycle = 4 full steps = 4*0.1125º=0.45º,Thus InvDistPerCycle = 1.0/0.45 = 2.22 (cycles/º) Commanding a move of 1.00 will generate 2.22 sine waves, or the equivalent of 8.88 full steps, or one º

Is that correct?. The main problem is that does not matther waht I put in the InvDistPerCycle as always makes the same movement, why can be that?

Many thanks again!!

Gonzalo

[TomKerekes]

Hi gonzalo,

The InvDistPerCycle setting doesn't apply to Step/Dir modes. It only applies to the modes where KFLOP is controlling sine wave currents to the motor (SnapAmp).

You can scale movement in Step/Dir mode with the OutputGain setting. With a standard 200 fullstep/rev motor and KStep's 16X microstepping there are 3200 steps/rev. So to scale to degrees:

OutputGain = 3200 steps/rev / 360 degrees/rev = 8.888889

Personally I prefer to leave KFLOP operating in Steps and do any scaling in the PC Application.

[gonzalo]

Many thanks Tom!!