Unsigned int

unsigned int

• Description
  

The size of unsigned int is same to int, occupying 2 bytes. It can only be used to store positive, and the range is 0~65,535 (2^16) - 1).

The most important difference between unsigned int and int is their peaks are different, namely the sign bit. In Arduino int, if the peak is 1, he number is taken as negative. The rest 15 btis are the values of the calculation according to the 2’s complement.

• Example
  

unsigned int ledPin = 13;

• Syntax

unsigned int var = val;

• var - the name of the unsigned variable
• val - the value to be assigned to the variable

• Note
  

When the value of the variable exceeds the maximum value it can represent, it will “roll back ”to the minimum value, and reverse will also appear this phenomenon.

   unsigned int x
       x = 0;
   x = x - 1;       //x is equal to 65535 now--roll back the negative direction
   x = x + 1;       //x is equal to 0 now--roll back

[Return to Arduino Syntax Manual]