Hobby Stepper (28BYJ-48)

This cheap stepper motor can move a number of steps with a reasonable degree of precision

Stepper motors can be expensive. A cheap option is the 28BYJ-48. It can’t be driven from the standard motor connections on the Kitronik board, but it comes with its own motor driver board.

Wire up

Connect the stepper as follows:

Add the library

You need to add the stepper-motor library. Copy stepper_28BYJ48.py from the lib directory on github to the lib directory on the pico

Code

Enter and run the following code:

See code on github

# Test the 28BYJ-48 stepper

import time
import board
import stepper_28BYJ48

# Create the stepper object
stepper = stepper_28BYJ48.Stepper(board.GP10, board.GP11, board.GP12, board.GP13)

# Move forwards and backwards
numSteps = 100
stepper.forward(numSteps)
stepper.backward(numSteps)
stepper.smoothForward(numSteps)
stepper.smoothBackward(numSteps)

The motor should move forwards and backwards 100 steps, then repeat in smooth mode.