little hep with button and led program

Projects Programming
1 
turn on a LED when the button is pressed and let it on 
until the button is pressed again
*/
int pinButton = 8;
int LED = 2;
int stateLED = LOW;
int stateButton;
int previous = LOW;
long time = 0;
long debounce = 200;
 
void setup() {
  pinMode(pinButton, INPUT);
  pinMode(LED, OUTPUT);
}
 
void loop() {
  stateButton = digitalRead(pinButton);  
  if(stateButton == HIGH && previous == LOW && millis() - time > debounce) {
    if(stateLED == HIGH){
      stateLED = LOW; 
    } else {
       stateLED = HIGH; 
    }
    time = millis();
  }
  digitalWrite(LED, stateLED);
  previous == stateButton;
}

 if(stateButton == HIGH && previous == LOW && millis() - time > debounce)

i don`t get this line of code and what &amp implementation in this code
i have some knowledge with c

2

i don`t get this line of code and what &amp implementation in this code

I guess that you copied this code from a Web page and it included HTML characters such as & as a substitute for &

The code should probably be

if(stateButton == HIGH && previous == LOW && millis() - time > debounce)
3

UKHeliBob:
I guess that you copied this code from a Web page and it included HTML characters such as & as a substitute for &

the place i copied this from is using a code format so i dont think HTML got to it
but i will try that edit
but can you explain please
what this -time debounce about ?

Thanks for help !

4

Ma-Mi:
but can you explain please
what this

-time debounce

about ?

I guess you mean the element from the if statement that should probably be

millis() - time > debounce

That makes perfect sense.

Steve

5

Ma-Mi:
the place i copied this from is using a code format so i dont think HTML got to it

Dude, HTML most certainly got into it.

Ma-Mi:
but can you explain please
what this -time debounce about ?

Any mechanical switch has "bounce" - it doen't just go on and off. When you operate the switch, it will go on-off a couple of times because of its mechanical elasticity. To deal with this, when a switch changes state sketches will usually ignore any further changes on the switch for a short interval of time - a few milliseconds or so.