How for loop conditions works in programming & how to use for-loop works in code are some questions that may arise while programming an Arduino.
Hello guys! Welcome back to my blog today we are going to
see about for loop in Arduino.
What are for loops in programming??
for loops is a conditional loop, use to execute some piece of code multiple times until the conditional satisfies. For example, if you want to print numbers 1 to 100 then instead of copy-pasting print statements 100 times, we can use for loop for printing numbers from 1 to 100. now we will see for loop in detail.
For loops are the combination of initiation, checking the condition, and increment or decrement alteration. Before knowing about for loop we will take some examples to get more clearance. Suppose you are using your phone and it needs to be charged so you connect the connector and put your phone on charging. Now you will see the battery getting charged in an increment manner example- 7%, 8%, 9%, and get charged until your phone reaches 100%. For loops also works as the same, you start charging from your actual battery percent, which is the initiation of your battery which is not 100% charged. So it continues to charge. For loop also increment iteration until it satisfies the condition.
For more clearance, we will take another example suppose you
want to press your clothes. So you turn ON your Iron and wait until your iron
gets hot. For that, you first set the desired temperature then the controller inside the iron every time checks & compares the current temperature with the desired
temperature that we have set whether its matches or not. When the temperature does not match then it increases the temperature and again checks until the present
temperature matches with the desired temperature that is set by you.
Here you can see you initialize your temperature, same as in
for loop then the controller checks for temperature, same as in for loop we check
for the condition. Then if the temperature which we set and the present temperature are not the same then the controller sends the command to increase the temperature and again compare
until the temperature reaches the desired value, same as in for loop we use to increment
or decrement iteration until the condition satisfies.
Now I hope you understand what for-loops does
Here initiation means to start at what value we are going to
start example – i=0, i=1, i=2, or j=0, i=2, etc.
The condition means to check the value whether it’s true or
false, equal or not, greater or less than between values. If conditions are not satisfied then increment or decrement the iteration until conditions are matched.
Now here we are initiating value i=0 then we will check the condition if i is less than or equal to 255. If it is less than 255 then it will increment the value i, i will become i=1. Then it will again check & compare the condition value of I will is 1 that is less than 255 again value of i will increment and will become i=2 again it will check and compare if the value of i which is 2 now is less than 255 again it will increment i=3. It will compare & increment until the value of i will be equal to 255. When i=256 which is equal to 255 then for loop will break.
Multiple LED glowing in a sequence using a for loop in Arduino
Connect positive pin of LED 1 to PIN no 2 of Arduino
Connect positive pin of LED 2 to PIN no 3 of Arduino
Connect positive pin of LED 3 to PIN no 4 of Arduino
Connect positive pin of LED 4 to PIN no 5 of Arduino
Connect the positive pin of LED 5 to PIN no 6 of Arduino
Connect positive pin of LED 6 to PIN no 7 of Arduino
Connect positive pin of LED 7 to PIN no 8 of Arduino
Connect positive pin of LED 8 to PIN no 9 of Arduino
Connect positive pin of LED 9 to PIN no 10 of Arduino
Connect the positive pin of LED 10 to PIN no 11 of Arduino
First, we have created an array that consists of pins of
Arduino pins from pin no 1 to 10. On each pin, we have connected a led. So in
total, we have 10 LEDs.
{
Serial.begin(115200);
for (int i=0;i<=total_ledpin;i++)
{
pinMode(ledpins[i],OUTPUT);
}
}
In the void setup, we have configured the baud
rate to 115200. We configure pins as INPUT or OUTPUT. We have to
declare the LED pin as output. Here we have 10 LEDs so instead of declaring each 10
LED pin as output. We will use for loop to declare LED pins. We will discuss for loop in detail. In for loop, we initialize the value of i as 0 first
and later increment till the value of i reaches the total length of LED which we
have declared as 10 (i = 0 to i =10). As we know
ledpins[i],
for i = 0 ledpins[0] = 2,
for i = 1 ledpins[1] = 3,
for i = 2 ledpins[2] = 4,
for
i = 3 ledpins[3] = 5,
for
i = 4 ledpins[4] = 6,
for
i = 5 ledpins[5] = 7,
for i = 6 ledpins[6] = 8,
for
i = 7 ledpins[7] = 9,
for i = 8 ledpins[8] = 10,
for
i = 9 ledpins[9] = 11
So using for loop we have
declared each LED pin of Arduino as OUTPUT
{
for(int i=0; i<=total_ledpin; i++)
{
Serial.println(ledpins[i]);
digitalWrite(ledpins[i],HIGH);
delay(1000);
}
for(int i=total_ledpin; i>=0; i--)
{
Serial.println(ledpins[i]);
digitalWrite(ledpins[i],LOW);
delay(1000);
}
}
In the void loop, we continuously turn all LEDs ON in a sequential manner and turn OFF LEDs in opposite direction. As above in void setup, as we use for loop to declare all LEDS pins as OUTPUT, the same we will do in the void loop to turn LED ON and turn LED OFF using the digitalWrite() function. The value of i corresponds to the index number of elements inside the array (LED pins). To turn LED ON we will increment the value of i with keyword HIGH inside digitalWrite() and to turn LED OFF we will decrement the value of i with keyword LOW inside digitalWrite().
Conclusion –
Today we will learn about for-loops, for loops in Arduino, what is for loops, and how to use for loops in programming. we have seen an example of for-loops using multiple LEDs. for loops are most commonly used in each and every programing language.
