0 1 2 3 4 5 6 7D0 HI HI LO LO LO LO LO HID1 LO HI HI HI LO LO LO LOD2 LO LO LO HI HI HI LO LOD3 LO LO LO LO LO HI HI HI
So the even steps would be the whole steps, while the odd steps would be the added half steps.
If I set D0 high and all others low, the motor takes one position. Then if I set D1 high and all others low, the motor rotates to next whole step. But if I leave D0 at high while D1 goes high, the motor takes the half step inbetween. What prevents from introducing microstepping here? Can't D1 go halfway high? Or is 5 wire unipolar so ancient technique that nobody bothers to develop microstepping drivers for them?