Arduino If statement

The if ( ) statement is the conditional statement, which is the basis for all types of programming languages.

If the condition in the code is true, the corresponding task or function is performed accordingly. It returns one value if the condition in a program is true. It further returns another value if the condition is false.

It means that if ( ) statement checks for the condition and then executes a statement or a set of statements.

Let's understand the concept with the help of a flow chart.

It clearly explains the process of execution of a statement. If the condition is False, it comes out of the if ( ) statement. If the condition is true, the function is performed.

The if ( ) statement is written as:

if ( condition)
{
// include statements
// if the condition is true
// then performs the function or task specified inside the curly braces
}

Here,

condition = It includes the boolean expressions, that can be true or false.

We can also use one or more operators inside the parentheses.

The comparison operators that can be used as a condition inside the parentheses are listed below:

a ! = b ( a not equal to b )
a < b ( a less than b )
a > b ( a greater than b )
a = = b ( a equal to b )
a < = b ( a less than or equal to b )
a > = b ( a greater than or equal to b )

where,

a and b are the variables.

Code Examples

Let's understand with the help of two coding examples.

Example 1:

Consider the below code.

int a = 6; // initiaization of values to variables a and b
int b = 4;
void setup()
{
Serial.begin(9600); 
}
void loop()
{
  if (a > b )
  {
    Serial.println( " a is greater than b "); 
  }
  if (b > a )
  {
    Serial.println( " b is greater than a "); 
  }
}

Output: a is greater than b

The code shows the initialization of values to the two variables a and b. In this example, the first condition is True. Hence the corresponding information is printed.

Example 2:

Consider the below code.

const int LED1 = 2;
const int LED2 = 13;
int x = 80 ;
void setup ( )
{ 
Serial.begin( 9600 );
pinMode ( LED1, OUTPUT);
pinMode ( LED2, OUTPUT);
}
void loop ( )
{ 
if ( x > 100 )
{
digitalWrite(LED1, HIGH);
delay (500);
}
if ( x < 100 )
{
digitalWrite(LED2, HIGH);
delay (500);
}
}

The example is of two LEDs.

In the above example, we have initialized the value of x. Since the value of x is less than 100, the second condition is true. Hence, LED2 will light up.

If the value of x is greater than 100, LED1 will light.

Similarly, we can use the if statement according to our requirements.