JIYIK CN >

random()This tutorial will discuss generating random numbers using the function in Arduino .

random()Generate random numbers in Arduino using the function

We use a random number generator to generate a random number within a given range of numbers. For example, we can use it to pick a winner for a giveaway.

We can random()generate random numbers in Arduino using the function.

grammar:

random(maxVlaue);
random(minValue, maxValue);

In the first line of code, if we only pass the maximum value of the range, the function will use zero as the minimum value. We can also random()define the minimum and maximum range using the first and second arguments of the function.

The minimum value of a range is inclusive, while the maximum value is exclusive. For example, if we define a range from 0 to 10, the random number sequence will include 0 but not 10.

Before using random()the function, we have to randomSeed()initialize it using the function. We have to randomSeed()pass a random number longdata type in the function to initialize the random number generator.

Suppose we want the random number to be the same sequence of numbers as the previous one. We have to randomSeed()pass the same number in the function.

If we want a different sequence of numbers, we have to use a different number each time we initialize the random number generator. In this case, we can use any analog pin of the Arduino.

When no input is connected to an analog pin, the pin will have a floating point value or a random value. We can analogRead()read this random value using the function.

For example, let's random()generate a random number between 0 and 100 using .

long MyRnd;

void setup() {
  Serial.begin(9600);
  randomSeed(analogRead(0));
}
void loop() {
  MyRnd = random(100);
  Serial.println(MyRnd);
  delay(500);
}

Output:

21
17
20
11
46
51
41
71
2
74

The random numbers will continue to be generated because we placed the random number generator in loop()the function. If we wanted to generate random numbers a specific number of times, we could setup()use a loop in the function, which would only run once.

The range value we random()defined in the function can be 32 bits. If you use a larger value, the function will not fail, but the result will be different from what you expect.

If we randomSeed()use 1the same number like in the function and restart the code, the sequence of random numbers will be the same.