RandomNumber

Functions
long	random (long min, long max)
void	randomSeed (unsigned long seed)

Detailed Description

Function Documentation

random()

long random	(	long	min,
		long	max
	)

Description

The random function generates pseudo-random numbers

Syntax

random(max);
rnadom(min, max);

Parameters

min(optional)	lower bound of the random value, inclusive(default = 0)
max	upper bound of the random value, exclusive

Returns

A random number between min and max-1(Type: long)

Example

void setup() {
  Serial.begin(115200);//UART0 baudrate 115200
  randomSeed(analogRead(0));
}

void loop() {
  Serial.print("Random number(0 ~ 999) : ");
  uint32_t l = random(1000);
  Serial.println(l);    

  //delay 1 second
  delay(1000);
}

randomSeed()

void randomSeed

(

unsigned long

seed

)

Description

randomSeed() initializes the pseudo-random number generator, causing it to start at an arbitrary point in its random sequence. This sequence, while very long, and random, is always the same.
If it is important for a sequence of values generated by random() to differ, on subsequent executions of a sketch, use randomSeed() to initialize the random number generator with a fairly random input, such as analogRead() on an unconnected pin

Syntax

randomSeed(seed);

Parameters

seed	number to initialize the pseudo-random sequence

Returns

void

Example

void setup() {
  Serial.begin(115200);//UART0 baudrate 115200
  randomSeed(analogRead(0));
}

void loop() {
  Serial.print("Random number(0 ~ 999) : ");
  uint32_t l = random(1000);
  Serial.println(l);

  //delay 1 second
  delay(1000);
}