Use this LED resistor calculator to find out the suitable resistance for your LED circuit consisting one or more LEDs.

As explained by Arduino to Go, each color band on the resistor corresponds to a number but this can differ depending on the band's placement. It's not complicated, but the sheer number of colors ...

Arduino Common cathode RGB LED 1mega ohm resistor (brown, black, green) Connecting wire A plant with its base Common PCB Circuit Diagram for Touch-Based Colour Changing Arduino Plant The complete ...

But there are really just the two speeds with the current programming. Inside the cool laser-cut box is an Arduino Uno and a 9V battery, plus a current-limiting resistor and the all-important buzzer.

LEDs: LED Arduino Pin Red LED D3 Yellow LED D4 Green LED D5 (Place a 220Ω resistor between each LED and GND.) Piezo Buzzer (2-pin): Buzzer Pin Arduino Pin Positive D7 Negative GND Explanation: RFID ...

This was controlled with an Arduino Uno. The LED matrix was mounted inside the shadow box, behind the vellum paper. The Arduino code was easily written using Adafruit’s RGB Matrix Panel library.