Digital Input/Output: Reflections

Date: Tuesday, 07/14/2026

Class: Interface Lab (IMALR-GT 104)

Section: 002

Name: Janice Vuong

Week: Week 2

Lab Notes: Digital Input and Output

~~Step 1: Set Up Power on the Breadboard~~

~~Step 2: Add a Digital Input (a Pushbutton in this case)~~

Step 3: Add Outputs (LEDs)

~~Step 4: Program our Arduino~~

~~Step 5: Upload and Test~~

Post-Class after receiving our Arduinos for the first time and putting together the jumper wires, resistors, a push button, and LED. I felt pretty overwhelmed. I felt overwhelmed because I was trying to assemble everything on the breadboard and keep up with the instructions in real time. But every other step during the assembly process I was always off by a pin, or a row, and it felt really discouraging. These feeling arose because I felt that if I couldn’t keep up Day 1, how would Day 20 feel like in class?

Then I cried (lol)

After class, and some gentle encouragement by my classmates (thank you Iris!!! and Miles! 🫶🏻) I attempted to tackle the breadboard again. I say breadboard, because my beef isn’t really with the Arduino (I mean it is the “brain” of the operation) however, I wasn’t struggling about the coding portion, but it was always about the assembly!!!!!

After a good 25 minutes, I finished putting all the pieces on my breadboard!! Or so I thought. For some reason only top LED (yellow LED) would light up when I pressed the switch button, and my red LED remain off. Luckily I could understand the code

void setup() {
  pinMode(2, INPUT);    // button
  pinMode(3, OUTPUT);   // red LED
  pinMode(4, OUTPUT);   // yellow LED
}

void loop() {
  if (digitalRead(2) == HIGH) {
    // button is pressed
    digitalWrite(4, HIGH);   // turn on yellow LED
    digitalWrite(3, LOW);    // turn off red LED
  } 
  else {
    // button is not pressed
    digitalWrite(4, LOW);    // turn off yellow LED
    digitalWrite(3, HIGH);   // turn on red LED
  }
}

and the problem was not with the code. The red LED on my breadboard should remain ON at all times! well it should turn off, only if I press the switch button (but otherwise, ON). So something was wrong on my breadboard (triggering).

After staring for a good 7 minutes, I realize my middle purple jumper cable was one pin off below (it should move 1 pin up), but I feel that as a total beginner, it is *really hard* to spot errors in my pin / assembly of the pieces on the breadboard.

After correcting my second jump cable, it worked!!!! It was a big relief :,)