Finally, here is my board (with Pololu drivers), at the moment controlled with SoundStepper (This board was originally designed as Bartels interface for EQ-6, that is why there is that 26-pin IDC connector on the left side, plus additional connectors for keypad and focuser).
Motor on the picture is 1.8° step/rev, and it works at maximum speed SoundStepper can deliver with no problems observed.
However, the current adjustment is critical: if too low, microstepping disappears, if too high, then the movement becomes jerky for some reason.
Later I plan to fit the heavy wheel on the motor shaft, this should help to further smoothen the movement.
Very happy !
