In this example we'll wire up and use a bi-polar stepper motor with recommended 9V motor voltage, and 200 steps per rotation.
Wiring
We'll wire it to a Metro, but you can use any microcontroller you like!
Connect:
- Vmotor to 9V (red wire)
- GND to ground
- SLP to > 2.7V power pin
- AIN1 to Digital 4
- AIN2 to Digital 5
- BIN2 to Digital 6
- BIN1 to Digital 7
Then hook one stepper motor coil to Motor A (red and yellow) and the second coil to Motor B (green and gray/brown). If you have another motor, you'll need to experiment a little to figure out which wires are which coil. Check any documentation you have! You can use a multimeter to measure between wires, the ones with a small resistance between them are a pair to a coil, for example. If the motor is vibrating but not spinning, check all wires are connected and try flipping around a pair or rechecking the wire pairs.
If you have a unipolar motor, there will be a 5th or 6th wire that is the 'common' wire. Connect these wires to the GND pins in between the Motor A and B outputs on the breakout.
Software
We'll use the built-in Arduino Stepper library, but you can manually toggle the AIN1/AIN2/BIN1/BIN2 pins with your own favorite microcontroller setup
#include <Stepper.h>
// change this to the number of steps on your motor
#define STEPS 200
// create an instance of the stepper class, specifying
// the number of steps of the motor and the pins it's
// attached to
Stepper stepper(STEPS, 4, 5, 6, 7);
void setup()
{
Serial.begin(9600);
Serial.println("Stepper test!");
// set the speed of the motor to 30 RPMs
stepper.setSpeed(60);
}
void loop()
{
Serial.println("Forward");
stepper.step(STEPS);
Serial.println("Backward");
stepper.step(-STEPS);
}
Basically after you make the Stepper object with the 4 control pins, you can set the rotational speed (in RPM) with setSpeed(rpm) and then step forward or backwards with .step(steps) where steps is positive for 'forward' and negative for 'backward'
