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Arduino Documentation

Arduino Reference Sheet


More info at: https://www.arduino.cc/reference/en/

Program Skeleton


Basic Commands in Arduino IDE

delay(value): waits a noted amount of time before moving on to following commands
  • value: a number denoting time in milliseconds (1000 milliseconds = 1 second)
digitalWrite(variable, setting): sets a component to on (HIGH) or off (LOW)
  • variable: name of the component
  • setting: Either HIGH or LOW
digitalRead(variable): returns the value of a noted component, either HIGH or LOW
  • variable: name of the component
analogWrite(variable, value): sets a component to a certain value from 0-255
  • variable: name of the component
  • value: A number 0-255
    • NOTE: can only be used when a component is plugged into a pin with ~symbol
analogRead(variable): returns the value of a noted component, a number 0-255
  • variable: name of the component
    • NOTE: can only be used when a component is plugged into a pin with ~symbol

Variables & Functions

int variable = value: creates an integer variable and assigns it a value
  • variable: name of the variable written in camelCase
  • value: A whole number (positive or negative)
void function(){}: defines a function as the commands found between the curly braces that will not return a value
  • function: name of the function, written in camelCase
  • To call the function, simply write the function name and a set of parentheses, ie. myFunction();
  • Parameters can be included in the parentheses
int function(){}: defines a function as the commands found between the curly braces that will return an integer
  • function: name of the function, written in camelCase
  • To call the function, simply write the function name and a set of parentheses, ie. myFunction();
  • Parameters can be included in the parentheses

Control Structures in Arduino IDE

If/Else Statements: Chooses actions to perform based on given conditions

if (condition) {
    commands;
}
else if (condition) {
    commands;
}
else {
    commands;
}
Example:
    if (digitalRead(button) == HIGH) {
        digitalWrite(motor, HIGH);
    }
    else {
        digitalWrite(motor, LOW);
    }

Sensor Conditions to use in if/else statements:

digitalRead(component): returns the digital value of a component as 1 (on) or 0 (off)
  • component: name of the component to be checked
analogRead(component): returns the analog value of a component
  • component: name of the component to be checked

For Loops: Repeats a set of actions a specific number of times

for (initialization; condition; increment) {
    commands;
}
Example:
    for (int i = 0; i < 4; i++) {
        analogWrite(redLED, count);
        count+=50;
    }

While Loops: Repeats a set of actions as long as a condition remains true

while (condition) {
    commands;
}
Example:
    while (digitalRead(button) == LOW) {
        digitalWrite(redLED, HIGH);
    }
    digitalWrite(redLED, LOW);

Arduino Operators

Mathematical Operators Comparison Operators Logical Operators
+ addition == Equal to ! Not
- subtraction != Not equal to && And
* multiplication < Less than || Or
/ division <= Less thanor equal to
% remainder/modulus > Greater than
>= Greater than or equal to