Just a quick Question..

Projects Programming
1

Hi everyone.

Can you please tell me where do i place this [void blink1] function in an arduino sketch??

should i place is before or after [ void setup () or void loop () ] ?
thank you ..

ps. i want to blink the led only once using function blink ()

2

You cannot put a function definition within another function.
A function can be placed anywhere else in the program
You can, of course, call a function from a function anywhere in the program
In order to take an action only once within a program either call it from setup() or control calling it with some logic.

3

Thank you Mr UKHelibob for your quick response.

Im reading " Arduino cookbook" to learn about programming and in the function chapter there is an example

// blink an LED once
void blink1()
{
digitalWrite(13,HIGH); // turn the LED on
delay(2000); // wait 2000 milliseconds
digitalWrite(13,LOW); // turn the LED off
delay(2000); // wait 2000 milliseconds
}

but when i upload the sketch in arduino in the following format it doesnt run accordingly .. what did i do wrong?

void setup ()
{pinMode (13, OUTPUT);}

void blink1()
{
digitalWrite(13,HIGH); // turn the LED on
delay(2000); // wait 2000 milliseconds
digitalWrite(13,LOW); // turn the LED off
delay(2000); // wait 2000 milliseconds
}

void loop () {}

ps. the led 13 only stays HIGH for 250 mseconds..

kind regards
lordStark

4

Hello,

but when i upload the sketch in arduino in the following format it doesnt run accordingly .. what did i do wrong?

here i try to remake your code,

int LED = 13;

void setup ()
{
  pinMode (13, OUTPUT);
}

void loop () 
{
  blink1();
}

void blink1()
{
digitalWrite(13,HIGH); // turn the LED on
delay(2000); // wait 2000 milliseconds
digitalWrite(13,LOW); // turn the LED off
delay(2000); // wait 2000 milliseconds
}
5

Here is your code formatted better (Auto Format in the IDE) and in code tags. Please do the same the next time you post code

void setup ()
{
  pinMode (13, OUTPUT);
}

void blink1()
{
  digitalWrite(13, HIGH); // turn the LED on
  delay(2000); // wait 2000 milliseconds
  digitalWrite(13, LOW); // turn the LED off
  delay(2000); // wait 2000 milliseconds
}

void loop () {}

You have a function named blink1() but you don't call it

Try this modified version

void setup ()
{
  Serial.begin(115200); //start the Serial interface
  pinMode (13, OUTPUT);
  blink1();
}

void blink1()
{
  Serial.println("In blink1");
  digitalWrite(13, HIGH); // turn the LED on
  delay(2000); // wait 2000 milliseconds
  digitalWrite(13, LOW); // turn the LED off
  delay(2000); // wait 2000 milliseconds
  Serial.println("Leaving blink1");
}

void loop () {}

Note that I have added a call to the blink1() function and debug statements to the function. Open the Serial monitor and set the baud rate to 115200 to see them

6

Thank you Mr Nielyay and UKHeliBob for taking the time to reply to my post

Appreciate your kind help.

kind regards
LordStark