LED Blink

September 20, 2025

Solving Approach

How do you plan to solve it?

To solve the LED blinking task using a microcontroller, I will begin by defining the timing requirements: the LED must stay ON for 400 milliseconds and OFF for 800 milliseconds in a continuous loop. Next, I’ll calculate the appropriate resistor value to ensure approximately 10 mA of current flows through the LED. Using Ohm’s Law and assuming a GPIO output voltage of 3.3V and an LED forward voltage of 2.0V, the resistor value comes out to 130 ohms. I’ll then construct the circuit by connecting a GPIO pin to one end of the resistor, the other end to the anode of the LED, and the cathode of the LED to ground. In the firmware, I’ll configure the GPIO pin as an output and implement the blinking logic using and functions to toggle the LED with the specified timing. Once the code is running, I’ll verify the current flow using a multimeter and confirm the blink pattern visually. If multitasking is needed later, I’ll refactor the code to use non-blocking timing with for better performance. This approach ensures both the electrical and timing specifications are met effectively

Code

const int ledPin = 2; // Replace with your actual GPIO pin

void setup() {
  pinMode(ledPin, OUTPUT);
}

void loop() {
  digitalWrite(ledPin, HIGH); // LED ON
  delay(400);                 // Wait 400 ms
  digitalWrite(ledPin, LOW);  // LED OFF
  delay(800);                 // Wait 800 ms
}

Output

Video

Add video of the output (know more)

https://drive.google.com/file/d/1ATO2Ui4cjzcAUNdNo4-nZCQ3XyzlJpIW/view?usp=drive_link

Photo of Output

Add a photo of your hardware showing the output.

https://wokwi.com/projects/442625930208037889

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