Stepper motor controller and Stepper motor TIMING

Hi,

which of these parameters depends only on Stepper motor controller and which also on Stepper motor

STEP TIME
STEP SPACE
DIRECTION HOLD
DIRECTION SETUP

I'm able to obtian timings for stepper motor controller [ A3979 ] but I think that these numbers also depends on stepper motor.
I know only Torque /RPM curve of stepper motor, so I can guess maximal RPM of motor, but not step time and step space.
My stepper motor doesn't provide any timing info - minimal time of one step and so on - so I'll have to try it

Is there some rule of thumb how much % of one step of stepper motor should be space and time of step ?

I've attached stepper motor controller timing

Thanx guys

Good place to start

Heres a quick calculator for speed and torque calculator

CG0: thank you, really good links

STEP TIME
STEP SPACE
DIRECTION HOLD
DIRECTION SETUP

Are only timings for the step drives input logic, the stepmotor itself never sees these signals.

However the maximum step rate will be limited to 1/(STEPTIME+STEPSPACE)

Typically the stepmotors inductance and power supply voltage
limits on the drives limit the maximum usable step rate, not the timing parameters

I thought that current flows to motor windings during STEP TIME

According to this calculator , my stepper motor [ inductance 3.6 mH , 19V, 1,4A] should has minimum step time 531us (This calculator computes the maximum speed of a stepper motor, which is limited by the time it takes for the coil to energize to it's maximum holding current, and then de-engergize as polarity flips) to run with high torque. My stepper motor controller has STEP Pulse Width 1 us.

So If I setup linuxcnc minimum step time 3 us, how will be motor's windings powered ( stepper speed 30mm/s ) - until another step or only 3 us ?


Stepper motor controller - A3979

Minimum Command Active Time
Before Step Pulse (Data Set-Up Time) ..... 200 ns
B. Minimum Command Active Time
After Step Pulse (Data Hold Time)............ 200 ns
C. Minimum STEP Pulse Width ...................... 1.0 μs
D. Minimum STEP Low Time ......................... 1.0 μs
E. Maximum Wake-Up Time ......................... 1.0 ms

I thought that current flows to motor windings during STEP TIME

No, STEPTIME is the minimum time needed by the input circuitry of the drive to recognize a step. Changing its width has no effect on the step motor current at all.
(as long as its long enough to be recognized and not so long that it violates the
STEPSPACE timimg of the next pulse)

The length of time that a coils is energized depends on the time _between_ step pulses
that is, 1/(step frequency)