Hardware:
attaching the stepper motor
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Check out the tutorial on this site for more detailed information on connection
Software:
Arduino Code on GitHub: https://github.com/tomjuggler/Stepper_Colour_Pointer
Processing Code on GitHub: https://github.com/tomjuggler/PupChooser
How does it work?
The Processing sketch sends Serial messages to the Arduino nano, numbers 1-8. The Arduino turns the Stepper Motor to the correct degree, pointing at the right pup
Press numbers 1-8 on the keyboard for different pups. Press ‘a’ for a random pup.