The pulse rate is not the same as the motor rpm's. In the case of a 16 point micro step, you would feed the driver chip 16x4 = 64 pulses to do one sine wave cycle on the motor. For a X1 (direct step) case each pulse would give you 1/4 of a sine wave cycle. If you have a 200 step per revolution motor, then you have 50 sine wave cycles per motor revolution. You have 200 step pulses per motor revolution at 1X. You have 3200 pulses per motor revolution at 16X. If you feed it a constant pulse rate on the step command line, it goes 1/16 the number of RPM's set to 16X compared to 1X. Regardless of how you have the microstepping set you get 50 sine wave cycles per revolution of the shaft.
The torque *may* drop off as the rpm's increase, a lot depends on the drive circuit and a few other things.
The torque *may* drop off as the rpm's increase, a lot depends on the drive circuit and a few other things.
