6 buttons and analog pin

Projects Programming
1

Hello everybody. I'm using A5 to read presses of 6 buttons and then printing what was pressed. The problem is that sometimes program registrates one press of a button as a couple of presses. Say I press first button twice, program sometimes will print number 1 (first button) three or four times. I suppose that it should be debounced, but i don't know how to do it on analog pin. On the picture, buttons go 1 to 6 from right to left.

int old_button = 0;
int button;
int pressed_button;
int z;

void setup () {
  pinMode(A5, INPUT);
  Serial.begin(9600);
}

void loop () { 
  z = analogRead(A5);
  if (z > 1021) button = 0;                                           
  else if (z > 511 && z < 514) button = 1;                     
  else if (z > 680 && z < 684) button = 2;                
  else if (z > 766 && z < 770) button = 3;                
  else if (z > 817 && z < 822) button = 4;             
  else if (z > 851 && z < 856) button = 5; 
  else if (z > 875 && z < 880) button = 6;
  else button = 0;                                                      
   
  if (old_button == button) {                                                                                       
    pressed_button = 0;                                               
  }  
  
  else {                                                                
    old_button = button;                                             
    pressed_button = button;                                        
  }

  Serial.println(pressed_button);
}

gumbi.jpg
gumbi.jpg1755×1284 325 KB

2

You have no delay in you sketch, the loop() is delayed only by the Serial.println().

You could add some timing and debounce with that, but using the analog input makes it harder.
What if you only delay() after a button is pressed. It is quick and dirty, but it might help a little.

....
else button = 0;                                                      
   
if (button != 0)
  delay( 20);

  if (old_button == button) {  
....
3

before reading buttons..:

while (analogRead(A5)<1010) {} // wait until button is released..