Setting up the circuit

But first, we gotta get basic.

Ingredients:

• Arduino Uno
• RGB LED with common anode configuration
• 330Ω resistor
• Breadboard
• Jumper cables

💡 Resistor choice (330Ω isn’t magic): 330Ω is a safe, common value for Arduino LED work.
Lower resistance = brighter (more current), higher resistance = dimmer (safer).
Also, different colours won’t be equally bright even with the same resistor.

⚠️ Arduino pin safety: Arduino pins are not power supplies. Always use resistors with LEDs and never try to drive high-current loads directly from I/O pins.

Circuit

• 5V of Arduino Uno to the resistor
• Connect the other end of resistor to common anode of LED
• Connect the other pins of the LED to the Arduino digital pins
  • RED -> pin 3
  • GREEN -> pin 5
  • BLUE -> pin 6

🎯 Why pins 3, 5, 6? These are PWM-capable on the Uno, which lets you smoothly control brightness later (instead of just ON/OFF).

🏷️ Wire-labelling saves you: keep track of which jumper is R / G / B. The #1 beginner bug is “wrong colour” caused by swapped LED legs.

✅ Resistor placement note: one resistor on the common anode limits the total current.
Best practice is one resistor per colour (R, G, B) for more consistent brightness and protection.

Arduino IDE

You can use:

• Lab computers
• Arduino Cloud
• Install Arduino IDE on your laptop

🛠️ In Arduino IDE, always verify you are using the correct COM Port (There is no majic trick, try them all until the uno flashes)

🔌 COM port not showing?

• Try a different USB port
• Make sure your cable is data-capable (some are charge-only)
• You can always ask us!

Test your Arduino is working

• Go to File > Examples > 01.Basic > Blink
• Select the correct COM Port
• Upload the file to your arduino

You should see the onboard LED blinking. (If not, please let one of the robotics officers know)