The LED array is pseudo-charlieplexed. One terminal of each LED goes to a GPIO pin on the micro-controller and the other terminal of all the LED’s are connected to a single complimentary pair of ...

The below circuit diagram shows the complete hardware wiring setup of the Arduino-based Smart Walking Stick for the Blind ...

Inside each box goes a colored LED, wired back to the Arduino. For the software, [Will] is using a floating analog pin as a source of random noise, and from there comes up with how often each LED ...

If your board has no printed labels, check out its pinout diagram documentation (found on the board's Arduino Store page). PWM pins in the diagram have the same tilde sign in front of the pin numbers.