Build gallery

Prompt

A cardboard traffic light with red, yellow, and green LEDs. Timed sequence like a real junction. Arduino Uno. Cutouts, wiring, and code.

Generated wiring

Generated code

// QA log: traffic light
const int RED = 8;
const int YEL = 9;
const int GRN = 10;

void setup() {
  pinMode(RED, OUTPUT);
  pinMode(YEL, OUTPUT);
  pinMode(GRN, OUTPUT);
}

void loop() {
  digitalWrite(RED, HIGH);
  delay(4000);
  digitalWrite(RED, LOW);
  digitalWrite(YEL, HIGH);
  delay(1000);
  digitalWrite(YEL, LOW);
  digitalWrite(GRN, HIGH);
  delay(4000);
  digitalWrite(GRN, LOW);
}

QA photos

No phone photo in the QA log yet for this build. Wiring and code above are the generated package.

Parts

• Arduino
• LEDs
• cardboard

Difficulty and time are from the QA log for this prompt, not a timed class period.

If this build gets stuck

• An LED never lights up
• How to upload code to your board