While loop not working?

Projects Programming
1

Hey, i am trying to make a device that you activate by pressing a button, then it creates a random delay, and you have to wait for this random amount of time, and when it has passed, either a led or a buzzer will go off (also randomly chosen), then you have to click again, and then it will tell you your reaction time based on two millis() timers. But i seem to have a problem on the very very last step, everything is working, but when the led or buzzer goes off, it just jumps straight past my while loop, doesent wait for a button click, it just jumps back to the beginning.
So i am either trying to make it so that it will get stuck in my while loop, or so that it will wait for a button press, before telling me my reaction time and going back to the beginning.
Any advice please??

#include <LiquidCrystal.h>
const int rs = 12, en = 11, d4 = 5, d5 = 4, d6 = 3, d7 = 2;
LiquidCrystal lcd(rs, en, d4, d5, d6, d7);
const int buzzerPin = 6;
const int buttonPin = 7;
const int ledPin = 8;
unsigned long int counter = 0;
unsigned long int reaction = 0;
int randomDelay = 0;
int randomVal1 = 0;
unsigned long int realReaction = 0;
int buttonState = 0;
int looper = 0;

void setup() {
randomSeed(analogRead(0));
lcd.begin(16, 2);
pinMode(6, OUTPUT);
pinMode(7, INPUT);
pinMode(8, OUTPUT);
}



void loop() {
introduction();
buttonState = digitalRead(buttonPin);
  if (buttonState == HIGH) {
    randomVal1 = random(0, 100);
    randomDelay = random(3000, 10000);
    lcd.setCursor(0, 0);
    lcd.print("Tap when you    ");
    lcd.setCursor(0, 1);
    lcd.print("notice sound/led");
    delay(randomDelay);
    reaction = millis();
    buzzerOrLed();
    buttonState = digitalRead(buttonPin);
    while (looper == 0) {
      lcd.setCursor(0, 0);
      lcd.print("Tap when you    ");
      lcd.setCursor(0, 1);
      lcd.print("notice sound/led");
      buttonState = digitalRead(buttonPin);
        if (buttonState == HIGH) {
          looper++;
          counter = millis();
          realReaction = (reaction - counter);
          lcd.setCursor(0, 0);
          lcd.print("                ");
          lcd.setCursor(0, 0);
          lcd.print(realReaction);
          lcd.setCursor(0, 1);
          lcd.print("                ");
        }
     }
  }
}

void introduction() {
  lcd.setCursor(0, 0);
  lcd.print("Press the button");
  lcd.setCursor(0, 1);
  lcd.print("to start test   ");
}

void buzzerOrLed() {
  if (randomVal1 > 53) {
  digitalWrite(ledPin, HIGH);
  delay(200);
  digitalWrite(ledPin, LOW);
  } else {
  tone(buzzerPin, 800);
  delay(200);
  noTone(buzzerPin);
  }
}
2

Three things:

  • Do not look at the level of a switch, look at when a switch changes state.

  • Avoid using while( ) loops as if they were a plague.

  • Only use delay( ) for very very short intervals, or not at all.

1 Like
3

Ive sat at this for a very long time now, tried switching from ifs to for to while loops, but nothing changes it, it just feels like it ignores it and just jumps over it

4

as I see it, the first time the program enters to the loop, and then it starts to jump over it, because the loop condition is not met

5

BTW, how is your switch wired ?

6

its connected from 5v to ground through a resistor, with a wire going from the same rail as the resistor from the switch to pin 7 on the arduino

7

Why do you think the program should wait for button click? I don't see anything like in your program... Could you point the line in the code where the program stops before button press?

8

Yes,
if (buttonState == HIGH) {
randomVal1 = random(0, 100);
randomDelay = random(3000, 10000);
lcd.setCursor(0, 0);
lcd.print("Tap when you ");
lcd.setCursor(0, 1);
lcd.print("notice sound/led");
delay(randomDelay);
reaction = millis();
buzzerOrLed();
buttonState = digitalRead(buttonPin);
while (looper == 0) {
lcd.setCursor(0, 0);
lcd.print("Tap when you ");
lcd.setCursor(0, 1);
lcd.print("notice sound/led");
buttonState = digitalRead(buttonPin);
if (buttonState == HIGH) {
looper++;
counter = millis();
realReaction = (reaction - counter);
lcd.setCursor(0, 0);
lcd.print(" ");
lcd.setCursor(0, 0);
lcd.print(realReaction);
lcd.setCursor(0, 1);
lcd.print(" ");
}
}
}
}

the second buzzorled is finished it just skips over the part i made thick text, no matter when i press the button

9

because after second buzzorled variable looper doesn't equal 0
and condition

while (looper == 0)

doesn't match

10

Hi,
I made some changes to your code:

unsigned long int counter = 0;
unsigned long int reaction = 0;
I changed to
unsigned long counter = 0;
unsigned long reaction = 0;

I commented out this line: // buttonState = digitalRead(buttonPin);

Added a delay of 5000, (5 secs). to view the reaction value on the LCD.
Modify the calculation of:
realReaction = (reaction - counter);
for
realReaction = (counter - reaction);
because the value in the previous format was negative.

I added the line: looper = 0;
to reset the looper every "round".

see how it turned out and test if it's what you need.
The delay I set to visualize can be changed to smaller values.

#include <LiquidCrystal.h>
const int rs = 12, en = 11, d4 = 5, d5 = 4, d6 = 3, d7 = 2;
LiquidCrystal lcd(rs, en, d4, d5, d6, d7);
const int buzzerPin = 6;
const int buttonPin = 7;
const int ledPin = 8;
unsigned long  counter = 0;
unsigned long  reaction = 0;
int randomDelay = 0;
int randomVal1 = 0;
unsigned long  realReaction = 0;
int buttonState = 0;
int looper = 0;

void setup() {
randomSeed(analogRead(0));
lcd.begin(16, 2);
pinMode(6, OUTPUT);
pinMode(7, INPUT);
pinMode(8, OUTPUT);
}
void loop() {
introduction();
buttonState = digitalRead(buttonPin);
  if (buttonState == HIGH) {
    randomVal1 = random(0, 100);
    randomDelay = random(300, 1000);
    lcd.setCursor(0, 0);
    lcd.print("Tap when you    ");
    lcd.setCursor(0, 1);
    lcd.print("notice sound/led");
    delay(randomDelay);
    reaction = millis();
    buzzerOrLed();
    //buttonState = digitalRead(buttonPin);
    while(looper == 0) {
      lcd.setCursor(0, 0);
      lcd.print("Tap when you    ");
      lcd.setCursor(0, 1);
      lcd.print("notice sound/led");
      buttonState = digitalRead(buttonPin);
        if (buttonState == HIGH) {
          looper++;
          counter = millis();
          realReaction = (counter - reaction);
          lcd.setCursor(0, 0);
          lcd.print("                ");
          lcd.setCursor(0, 0);
          lcd.print(realReaction);
          lcd.setCursor(0, 1);
          lcd.print("                ");
        }
     }
     delay(5000);
  }
  looper = 0;
}

void introduction() {
  lcd.setCursor(0, 0);
  lcd.print("Press the button");
  lcd.setCursor(0, 1);
  lcd.print("to start test   ");
}

void buzzerOrLed() {
  if (randomVal1 > 53) {
  digitalWrite(ledPin, HIGH);
  delay(200);
  digitalWrite(ledPin, LOW);
  } else {
  tone(buzzerPin, 800);
  delay(200);
  noTone(buzzerPin);
  }
}

PS: Sorry.
Hi,
To make it faster just for testing I modified the delay calculation parameters.

11

but i set it to 0 when i declared it

12

Well now it sort of works, it does give me a reaction time
im going to se if i can change it a little bit and se if i can get it working how i inteded it to, but thank you

13

you increment it in code, but never decrement again.

14

ooooh right, thats ture

15

Hi,
To make it faster just for testing I modified the delay calculation parameters.

16

Yeah i noticed, it works perfectly now, but i dont fully understand what change made it work

17

Hi,
The main change was the inclusion of the line: looper = 0;

18

looper =0; and delay(5000); at the end of loop()

19

Ahh i see thanks

20

Yeah i think i get it now