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the_digital_dentist
At 256:1 this thing can't go fast enough for a 3D printer (OK, it would be fine in the Z axis) and it can't supply enough current for a CNC router or mill.
Off course this is nothing for the 8-bit electronics, but most 32-bit µCs have enough power to drive the high step rates required. We finally arrived in the 21st century
with marlin 2.0 supporting the new electronics… or take a look at Klipper.. Smoothieboard 2 pro even promises to have an FPGA for step pulse creation...and so on.
Quote
dc42
All the commonly-used Trinamic drivers can do genuine x256 microstepping - or any other binary microstepping between x1 and x256. But they also offer the ability to interpolate to x256 - in some models only from x16, in other models from any lower microstepping.
I just checked the datasheets and the TMC 2130 and the TMC2208 actually do have native 256 microsteps, I honestly didn´t know this. The TMC2100 does just the interpolation from
1/16th microstepping and was the first driver that was available in a pololu package. The newer chips actually do offer the native 1/256th microstepping only through their respective ways of configuring the chip digitally, but when doing it with the MSx pins they again only offer the interpolated 1/16th microstepping, which is what mislead me.
Ok, cool so the Trinamic drivers do actually have native 1/256th microstepping, I did not know this.
But to be honest the whole 1/256th microstepping thing is a bit over the top. As I already said, the motors can´t really reslove the half a million steps per revolution, the torque diminishes to almost nothing and when applied to 3D printing, even the differences from 1/16th to 1/32th microstepping in print quality are very hard to see, if at all. The motor noise however goes down a lot, but then again you can interpolate and have about the same results. Trinamic does this for a reason.
Also, I just looked at the pololu website and they have quite a few new drivers since I last checked, most noteably the ST820 and also the TB67S249 driver which can deliver currents of 1.5A(4.5Apeak!) this is quite a lot, and it even can handle 47V... this now is really something very useable for CNC and Nema23s!