Arduino Cheat Sheet

The majority of content found on this cheat sheet comes from the official Arduino documentation, if you find that something is lacking please comment and I will update this post accordingly.

Including Files

#include <Adafruit_GFX.h>

Using #include <...> the compiler searches in an implementation dependent manner, normally in search directories pre-designated by the compiler/IDE

#include "joystick.h"

Using #include "..." the compiler searches in the same directory as the file containing the directive.

Data Types

Below is a complete list of all data types available when programming on the Arduino platform. I will try to keep this section up to date as I learn more.

Type	Example	Storage	Range
void	void setup() { ... }	-	-
boolean	true	1 byte (8 bit)	true	false
char	'A'	1 byte (8 bit)	-
byte	128	1 byte (8-bit)	0 to 255
int	64	2 byte (16 bit)	-2,147,483,648 to 2,147,483,647
word	10000	–	2	4 byte (16	32-bit)
long	186000L	4 bytes (32 bits)	2,147,483,648 to 2,147,483,647
short	13	2 bytes (16 bits)	-32,768 to 32,767
float	-	4 bytes (32 bits)	-3.4028235E+38 to 3.4028235E+38
double	1.117	8 bytes (64 bits)*	…
string char[]	"arduino"	varies	varies
String	"arduino"	varies	varies
array	vals[0] == 2	varies	varies

Core Methods

Some useful methods / functions for writing your applications.

delay()

Pauses the program for the amount of time (in milliseconds) specified as parameter. (There are 1000 milliseconds in a second.)

delay(1000)

Working with IO

Useful methods when working with Arduino pins.

// Sets the pin as input (using internal pullup resistor)
pinMode(JOY_BTN, INPUT_PULLUP);

// Sets the pin as an input
pinMode(JOY_X, INPUT);

// Reads data from an analog pin (0-1024)
int aData = analogRead(pinX);

// Reads data from a digital pin (0-1)
int dData = digitalRead(pinBtn);

• Digital - used to read high or low (1 or 0)
• Analog - used to read a value between 0 and 1024

Working with Serial.

// Start serial @ 9600 bps
Serial.begin(9600);

// Append given value to current line
Serial.print("...");

// Append given value to line and insert a line break
Serial.println("...");

Comments

// (single line comment)
/* */ (multi-line comment)

Constants

HIGH | LOW
INPUT | OUTPUT | INPUT_PULLUP
LED_BUILTIN
true | false

Time

• millis()
• micros()
• delay()
• delayMicroseconds()

Math

• min()
• max()
• abs()
• constrain()
• map()
• pow()
• sqrt()
• sin()
• cos()
• tan()

Characters

• isAlphaNumeric()
• isAlpha()
• isAscii()
• isWhitespace()
• isControl()
• isDigit()
• isGraph()
• isLowerCase()
• isPrintable()
• isPunct()
• isSpace()
• isUpperCase()
• isHexadecimalDigit()

Random Numbers

• randomSeed()
• random()

Bits and Bytes

• lowByte()
• highByte()
• bitRead()
• bitWrite()
• bitSet()
• bitClear()
• bit()

Interrupts

• attachInterrupt() - External
• detachInterrupt() - External
• interrupts()
• noInterrupts()