Operating a stepper motor through a driver circuit
Connect a momentary switch or a low frequency 5V CMOS logic relaxation (Schmitt Inverter)oscillator with a pot. and Connect to Step. with Vdc =24V

Each positive pulse ( and switch bounce) will rotate CW 1 step with typ 200 steps per rev so 200 Hz is 60 RPM

Then vary pot from 1Hz to 1Khz to change slow RPM in steps







simulate this circuit &ndash; Schematic created using CircuitLab

15 us is the shortest STEP CLK pulse spec and it is edge sensitive.