DRV8825 Can't set 1/16 stepping (1 reply)

Hello

My Core XY was working fine on A4988 drivers until a slight mis-hap.

I had to replace the drivers and replaced them with DRV8825 chips.

I doubled my steps per unit from 80 to 160 to allow for the 1/32 step.

X & Y while correct would occasionally miss steps. I increased current from ref volts up to about 0.6V and still it missed steps. (1.2A motors)

I've read some doubts about using 1/32 stepping on RAMPS. Whether true or not I don't know.

I removed jumper MS3 (furthest from capacitor below the driver) thinking it would give me 1/16 stepping.
It seems that that has set it to 1/8 stepping.

(I halved my steps per unit back to 80.The travel was double expected. I halved the steps again and it was correct. Implying that it is 1/8 stepping)

Any suggestions how to get 1/16 stepping?

Also - even at 1/8 stepping it seems to be missing steps. It's hard to tell whether X or Y with the coreXY set up. It's making some horrible grinding stuttering. Reducing acceleration didn't help.

Any suggestions?

Thanks

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