Thanks guys for the info. I'm about to try the TMC2130's for my BigBot printers and integrate positional error checking:) "Sounds" like I can expect better performance than the DRV8825's even, which I think perform very well, even from the arduino mega 8-bit controller.
To answer a previous question, the micro-stepping frequency doesn't have much to do with top speed of a motor. Voltage determines speed, and armature resistance and impedance thereby determine current current flow.
It's simpler to understand it in non-technical terms:
Stepper motors speeds are limited because the power supply voltage becomes not much more than the motor voltage (it's a generator when it's moving). When the voltage between motor and power supply is low, V=IR means your current from drops eventually to zero, and then your motor cannot spin any faster... more power cannot get into the motor because it holds a similar voltage to the power supply.
To help clear up some things also...more steps beyond 1/8 stepping or so does not mean more useable resolution, or a smoother drive. It's just that when the drive sends step pulses at a higher frequency the resulting pitch at that given rpm is above 20khz, and is now out of our audible range for speeds over 15mm/s or so, depending on your printer. All motors are also like speakers in that way, and tis why the pitch gets higher when the motor moves faster, and using non-tmc drivers that pitch is audible.
To answer a previous question, the micro-stepping frequency doesn't have much to do with top speed of a motor. Voltage determines speed, and armature resistance and impedance thereby determine current current flow.
It's simpler to understand it in non-technical terms:
Stepper motors speeds are limited because the power supply voltage becomes not much more than the motor voltage (it's a generator when it's moving). When the voltage between motor and power supply is low, V=IR means your current from drops eventually to zero, and then your motor cannot spin any faster... more power cannot get into the motor because it holds a similar voltage to the power supply.
To help clear up some things also...more steps beyond 1/8 stepping or so does not mean more useable resolution, or a smoother drive. It's just that when the drive sends step pulses at a higher frequency the resulting pitch at that given rpm is above 20khz, and is now out of our audible range for speeds over 15mm/s or so, depending on your printer. All motors are also like speakers in that way, and tis why the pitch gets higher when the motor moves faster, and using non-tmc drivers that pitch is audible.