Difference Between 4-Wire, 6-Wire and 8-Wire Stepper Motors - NI
stepper-motors [smoothieware.org]
Stepper Motor wiring with an Oscilloscope
Controlling Stepper Motors Using Power IO Wildcard, C Library Functions and MOSFET Drivers for Four-phase Six-wire Unipolar Permanent-magnet Stepper Motor
Stepper Motor Basics - 4 Wires Bipolar Motor - YouTube