Using C Standard Variable Types

This can be essential if using a 32bit Arduino and needing a 16bit varaible or for any code which needs to be sure what size and int variable is

#include <stdint.h>

bool

boolean

char

-128 to 127

byte

0 to 255

short

unsigned short

int

unsigned int

long

unsigned long

long long

unsigned long long

float

double

int8_t

-128 to 127

uint8_t

0 to 255

int16_t

-32,768 to 32,767

uint16_t

0 to 65,535

int32_t

-2,147,483,648 to 2,147,483,647

uint32_t

0 to 4,294,967,295

int64_t

−9,223,372,036,854,775,808 to 9,223,372,036,854,775,807

uint64_t

0 to 18,446,744,073,709,551,615

Handy Typedefs To Use

#include <stdint.h>
typedef bool BOOL;
typedef uint8_t BYTE;
typedef int8_t INT8;
typedef uint8_t UNINT8;
typedef int16_t INT16;
typedef uint16_t UINT16;
typedef int32_t INT32;
typedef uint32_t UNINT32;
typedef int64_t INT64;
typedef uint64_t UINT64;

 

Display Memory Size Of All C Types

#include <stdint.h>

void setup() {
  Serial.begin(9600);
}

void loop() {
  Serial.print("sizeof(byte)=");
  Serial.println(sizeof(byte));
  Serial.println();
  
  Serial.print("sizeof(char)=");
  Serial.println(sizeof(char));
  Serial.println();
  
  Serial.print("sizeof(short)=");
  Serial.println(sizeof(short));
  Serial.println();
  
  Serial.print("sizeof(int)=");
  Serial.println(sizeof(int));
  Serial.println();
  
  Serial.print("sizeof(long)=");
  Serial.println(sizeof(long));
  Serial.println();
  
  Serial.print("sizeof(long long)=");
  Serial.println(sizeof(long long));
  Serial.println();
  
  Serial.print("sizeof(bool)=");
  Serial.println(sizeof(bool));
  Serial.println();
  
  Serial.print("sizeof(boolean)=");
  Serial.println(sizeof(boolean));
  Serial.println();
  
  Serial.print("sizeof(float)=");
  Serial.println(sizeof(float));
  Serial.println();
  
  Serial.print("sizeof(double)=");
  Serial.println(sizeof(double));
  Serial.println();
  
  Serial.print("sizeof(int8_t)=");
  Serial.println(sizeof(int8_t));
  Serial.println();
  
  Serial.print("sizeof(int16_t)=");
  Serial.println(sizeof(int16_t));
  Serial.println();
  
  Serial.print("sizeof(int32_t)=");
  Serial.println(sizeof(int32_t));
  Serial.println();
  
  Serial.print("sizeof(int64_t)=");
  Serial.println(sizeof(int64_t));
  Serial.println();
  
  Serial.print("sizeof(uint8_t)=");
  Serial.println(sizeof(uint8_t));
  Serial.println();
  
  Serial.print("sizeof(uint16_t)=");
  Serial.println(sizeof(uint16_t));
  Serial.println();
  
  Serial.print("sizeof(uint32_t)=");
  Serial.println(sizeof(uint32_t));
  Serial.println();
  
  Serial.print("sizeof(uint64_t)=");
  Serial.println(sizeof(uint64_t));
  Serial.println();
  
  Serial.print("sizeof(char*)=");
  Serial.println(sizeof(char*));
  Serial.println();
  
  Serial.print("sizeof(int*)=");
  Serial.println(sizeof(int*));
  Serial.println();
  
  Serial.print("sizeof(long*)=");
  Serial.println(sizeof(long*));
  Serial.println();
  
  Serial.print("sizeof(float*)=");
  Serial.println(sizeof(float*));
  Serial.println();
  
  Serial.print("sizeof(double*)=");
  Serial.println(sizeof(double*));
  Serial.println();
  
  Serial.print("sizeof(void*)=");
  Serial.println(sizeof(void*));
  Serial.println();
  
  while (1)
    delay(10000);
}