So the stepper motor circuit is working on the bread board. At the moment I have it spinning contiuously. The next step is to have it controlled from the computer.Arduino can accept data in via various methods.
- USB – which also supplies power
- Analogue – which is read as voltage differential i think ±5v probably
- Digital – high low based on the outputs
USB is easiest on the bench. That would require the final computer to have USB which isn’t too much of an ask so i will begin there.[flv:/wp-content/uploads/2007/12/stepper-02mov-100k.flv /wp-content/uploads/2007/12/stepper-02mov.png 320 240]
Parts list
- ULN2003N integrated circuit [3.5AUD] rather than the ULN2003A listed at the Arduino page. Logic diagramme is here
- YM-2751 unipolar stepper motor [18.95AUD] – a 6 wire 7.5° 12V motor
- Arduino ATMEGA8 board
Notes
- Arduino StepperUnipolar tutorial.
- Arduino pins 8 – 11 are wired via the ULN2003N IC ( Arduino to the bottom, motor to the top ). This may be incorrect, as occassionally I get momentary lock ups, and the steps are uneven ( big, small, big, small ) although there are 48 in a circuit.
- Green and grey cables ( listed at A2 and B2 COM on the spec sheet ) are cabled to +5V power on the Arduino.
- The IC is grounded to the Arduino on its lower right hand pin.