I have a 28BYJ-48 stepper motor with a ULN2003 driver that I have successfully operated in half-step mode, which is pretty much what everyone seems to be using. I want to sacrifice resolution for speed and operate in full step mode, but I haven't been able to get it to work. In half-step mode with long delays between phases, I can confirm the signal sequence via the UNL2003 driver LEDs is
In full-step mode, I can confirm with the LEDs on the ULN2003 driver that the inputs are applied in the following sequence.
However, the stepper doesn't move, though I can feel it pulsing. I'm using a 5 VDC power adapter to power the UNL2003 driver rather than the Raspberry Pi power. Has anyone gotten full-step mode to work with this stepper and driver?