Arduino Basics
- 4 days ago
- 1 min read
Example Code for LED
pinMode(LED_BUILTIN, OUTPUT);
Tells the Arduino that the built‑in LED pin (usually pin 13 on most boards) will be used to send signals out, not read them in.
“OUTPUT” means we’ll control something like turning a light on or off.
digitalWrite(LED_BUILTIN, HIGH);
Sends a HIGH signal (5 V) out of that pin.
For an LED, that means turn it ON.
Example Code for Button Press
Serial.begin(9600);
This line starts serial communication between the Arduino and your computer.
9600 is the speed of that communication, called the baud rate — it means 9600 bits per second.
Once started, you can use commands like Serial.print() to show data (like the button state) in the Serial Monitor.
buttonState = digitalRead(buttonPin);
digitalRead() checks whether the pin (buttonPin) is getting a HIGH or LOW voltage.
It returns either:
HIGH (1) → the button is pressed (current is there), or
LOW (0) → the button is not pressed.
Example Code for Button LED Control
if (buttonState == HIGH);
It checks whether the variable buttonState equals HIGH.
HIGH means the pin is receiving voltage (usually 5 V), so in a button circuit, that usually means the button is pressed.
The == in programming means “is equal to”, not “assign.” (People often mix this up with = which means “store the value.”)
Example Code for IR LED Control
Example Code for Servo
Example Code for IR Servo Control
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