Ok, on the advise of @canis_gee I bought some anycubic TMC2100 drivers.
I cut the config pins, and bridged across config1 to ground to set the right step mode.
However, I’m having some issues.
EDIT - it seems like the DRV8825 on the zim is set up for 1/32nd microstepping, so i’ll need to update the firmware to put out 1/16th
First off, its inverted. I can handle that in firmware. If i try to do it in octoprint, it goes the wrong way even with x/y inverted, and it doesn’t hit the stops right. But, curious, as the DRV8825 and the TMC2100 should have the same direction settings.
The other problems I’m having is that the speed/steps seem to be wonky. Since I’m going from the DRV, it should be setup for 1/16th step already, but i had to set the max feedrate way down to 1000mm/min, so there’s something wrong here.
Third, is the ref voltage. It’s really hard to keep the zim connected and try to tune these things, so I’d like some idea of what others are running for ref voltage? The DRVs were set to 0.25V, but the formula is different. I went with 0.5V, which gives max of 1A, but it may be contributing to my problems
So, for those running it
Inverted XY or no?
What reference voltage?
What value for DEFAULT_AXIS_STEPS_PER_UNIT?
Any other config changes necessary?
Thanks!