These pushbuttons are a great addition to any LEGO Mindstorms or Bricktronics project, and we used them in the Keytar project of the Make: Lego and Arduino Projects book. Despite being much less expensive than the official LEGO pushbutton sensors, these pushbuttons are still 100% compatible with both the original NXT control brick as well as the Bricktronics Shield and Megashield.
To integrate these pushbuttons with your project, simply wire them into an NXT cable such that the white wire (pin 1) is connected to one side of the switch, and the black and red wires (pins 2 and 3) are connected to the other side of the switch (more details available here).
We also carry laser-cut 1/8" (3mm) plywood mounting plates for these buttons.
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