Make millis timer wait until a if statement i true(Need help)

fotokoppen · December 13, 2022, 10:14am

int interval=20000;

unsigned long previousMillis=0;

void loop() {

unsigned long currentMillis = millis();

if (bdistance >=15 && bdistance <=1){
  previousMillis = currentMillis;
}

if ((unsigned long)(currentMillis - previousMillis) >= interval) {
  
  Serial.println("FullFULLFULL");
  previousMillis = currentMillis;

}
}

Why wont it work

Idahowalker · December 13, 2022, 10:15am

The code does not work because it is missing a setup() function.

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UKHeliBob · December 13, 2022, 10:17am

Welcome to the forum

Do you realise that you have posted in the forum section where users giving help expect to be paid ?

b707 · December 13, 2022, 10:19am

Because once you first if statement becomes true, value previousMillis will reinitialized every loop() runs and the second condition never match.
You need to initialize previousMillis only once, use a flag:

nt interval=20000;
unsigned long previousMillis=0;
bool interval_is_running = false;

void loop() {

unsigned long currentMillis = millis();

if (bdistance >=15 && bdistance <=1){
  if (! interval_is_runnung) 
      previousMillis = currentMillis;
  interval_is_runnung = true;
}

if ((currentMillis - previousMillis) >= interval) {
    Serial.println("FullFULLFULL");
    previousMillis = currentMillis;
  }
}

fotokoppen · December 13, 2022, 11:53am

ooooh, where do i post?

fotokoppen · December 13, 2022, 12:24pm

Hi, thanks for the respond!

It's still not working for me, is there anything i'm missing out?

#include<Servo.h>

Servo servo;
Servo servo2;

int const trigPin = 6; //navngir pin 6 til trigPin
int const echoPin = 5;
int const btrigPin = 10;
int const bechoPin = 11;

int interval=20000;
unsigned long previousMillis=0;
bool interval_is_running = false;

void setup() { //Denne koden køyres kun eingong
Serial.begin(9600); //Bits per sekund
pinMode(trigPin, OUTPUT); //Gjør trigPin om til Output
pinMode(echoPin, INPUT); //Gjør echoPin om til Input
pinMode(btrigPin, OUTPUT);
pinMode(bechoPin, INPUT);

servo.attach(3);
servo2.attach(9);

}

void loop() { //Denne koden køyres heile tida
digitalWrite(trigPin,LOW);
delayMicroseconds(2);
digitalWrite(trigPin, HIGH); //Gjøpr trigpin om til HIGH eller 1
delayMicroseconds(2);
digitalWrite(trigPin, LOW); //Gjør trigPin om til LOW eller

long timedelay = pulseIn(echoPin, HIGH);
int distance = 0.0343 * (timedelay/2);
if (distance <=50 && distance >=1) {  //Visst noko er mellom 0cm og 50cm så kjører det denne if koden
        servo.write(80);  //Justerer servoen til 50 grader
        servo2.write(140);
      delay(3000); //venter 3 sekund
}   else {

          servo.write(180); //Gjør servoen om til 160 grader som gjør til at lokket lukker seg.
          servo2.write(40);//Gjør servoen om til 40 grader som gjer at lokket lukker seg.
}
delay(60);

delayMicroseconds(2);

digitalWrite(btrigPin,LOW);
delayMicroseconds(2);
digitalWrite(btrigPin, HIGH); //Gjøpr trigpin om til HIGH eller 1
delayMicroseconds(2);
digitalWrite(btrigPin, LOW); //Gjør trigPin om til LOW eller 0


long td = pulseIn(bechoPin,HIGH);
int bdistance = 0.0343 * (td/2);

unsigned long currentMillis = millis();

if (bdistance >=15 && bdistance <=1){
if (! interval_is_running)
previousMillis = currentMillis;
interval_is_running = true;
}

if ((currentMillis - previousMillis) >= interval) {
Serial.println("FullFULLFULL");
previousMillis = currentMillis;
}

delay(1000);

Serial.println(currentMillis);
Serial.println(previousMillis);
Serial.println(bdistance);

Idahowalker · December 13, 2022, 12:25pm

Use code tags (the </> icon above the compose window) to make it easier to read and copy for examination

Could you edit your post#6 to use code tags?

If you are unable to understand how to use code tags then getting help may be difficult.

And post the complete code, please.

b707 · December 13, 2022, 12:28pm

The code tags perhaps?

Your code is very inconvenient to work with, please fix it

fotokoppen · December 13, 2022, 12:38pm

Yeah im sorry for that, i'm a bgeinner and it's a scholl project with little to no help from the teachers. I tried to make it better to read if thats what you meant by inconvenient

#include<Servo.h>

Servo servo;
Servo servo2;

int const trigPin = 6;
int const echoPin = 5;
int const btrigPin = 10;
int const bechoPin = 11;

int interval=20000;
unsigned long previousMillis=0;
bool interval_is_running = false;

void setup() {
Serial.begin(9600);
pinMode(trigPin, OUTPUT);
pinMode(echoPin, INPUT);
pinMode(btrigPin, OUTPUT);
pinMode(bechoPin, INPUT);

servo.attach(3);
servo2.attach(9);

}

void loop() {
digitalWrite(trigPin,LOW);
delayMicroseconds(2);
digitalWrite(trigPin, HIGH);
delayMicroseconds(2);
digitalWrite(trigPin, LOW);

long timedelay = pulseIn(echoPin, HIGH);
int distance = 0.0343 * (timedelay/2);
  if (distance <=50 && distance >=1) { 
        servo.write(80);  
        servo2.write(140);
        delay(3000); 
    } 
  else {

        servo.write(180); 
        servo2.write(40);
   }
delay(60);

delayMicroseconds(2);
digitalWrite(btrigPin,LOW);
delayMicroseconds(2);
digitalWrite(btrigPin, HIGH); 
delayMicroseconds(2);
digitalWrite(btrigPin, LOW); 


long td = pulseIn(bechoPin,HIGH);
int bdistance = 0.0343 * (td/2);


unsigned long currentMillis = millis();

if (bdistance >=15 && bdistance <=1){
  if (! interval_is_running) 
    previousMillis = currentMillis;
     interval_is_running = true;
   }

if ((currentMillis - previousMillis) >= interval) {
Serial.println("FullFULLFULL");
previousMillis = currentMillis;
}

Serial.println(currentMillis);
Serial.println(previousMillis);
Serial.println(bdistance);

}

b707 · December 13, 2022, 12:41pm

your code still not inserted correctly.
Please reread advices in posts #7 and #2

UKHeliBob · December 13, 2022, 12:46pm

I have moved the topic to the Programming category

fotokoppen · December 13, 2022, 12:47pm

I need help to figure out how to make my millis timer work properly, it need to "stop counting" when bdistance is >15 and <1.

#include<Servo.h>

Servo servo;
Servo servo2;

int const trigPin = 6;
int const echoPin = 5;
int const btrigPin = 10;
int const bechoPin = 11;

int interval=20000;
unsigned long previousMillis=0;
bool interval_is_running = false;

void setup() {
Serial.begin(9600);
pinMode(trigPin, OUTPUT);
pinMode(echoPin, INPUT);
pinMode(btrigPin, OUTPUT);
pinMode(bechoPin, INPUT);

servo.attach(3);
servo2.attach(9);

}

void loop() {
digitalWrite(trigPin,LOW);
delayMicroseconds(2);
digitalWrite(trigPin, HIGH);
delayMicroseconds(2);
digitalWrite(trigPin, LOW);

long timedelay = pulseIn(echoPin, HIGH);
int distance = 0.0343 * (timedelay/2);
  if (distance <=50 && distance >=1) { 
        servo.write(80);  
        servo2.write(140);
        delay(3000); 
    } 
  else {

        servo.write(180); 
        servo2.write(40);
   }
delay(60);

delayMicroseconds(2);
digitalWrite(btrigPin,LOW);
delayMicroseconds(2);
digitalWrite(btrigPin, HIGH); 
delayMicroseconds(2);
digitalWrite(btrigPin, LOW); 


long td = pulseIn(bechoPin,HIGH);
int bdistance = 0.0343 * (td/2);


unsigned long currentMillis = millis();

if (bdistance >=15 && bdistance <=1){
  if (! interval_is_running) 
    previousMillis = currentMillis;
     interval_is_running = true;
   }

if ((currentMillis - previousMillis) >= interval) {
Serial.println("FullFULLFULL");
previousMillis = currentMillis;
}

Serial.println(currentMillis);
Serial.println(previousMillis);
Serial.println(bdistance);

}

J-M-L · December 13, 2022, 12:54pm

millis() never stops really..

what do you mean exactly?

b707 · December 13, 2022, 12:56pm

@fotokoppen
Using a mess of millis and delay logic in one code is a way to fail

I still not understand what is your problem.

J-M-L · December 13, 2022, 12:57pm

is this the same question as

don't double post please.. Merging topics.

gcjr · December 13, 2022, 1:01pm

click the </> icon and paste your code in the highlighted area

bdistance can' t be <1 and >15

i think your logic can be simpler

    unsigned long currentMillis = millis();

    if (1 <= bdistance &&  bdistance <= 15)  {
        if ((currentMillis - previousMillis) >= interval) {
            previousMillis = currentMillis;
            Serial.println("FullFULLFULL");
        }
    }

fotokoppen · December 13, 2022, 1:46pm

YEah i was confused where to post

fotokoppen · December 13, 2022, 1:51pm

Well basically i have a box with two sensor, one of the open the box with servos(which works). i also wanted to add the function that whenm the box gets full it starts a timer and send a message in serial monitor every 20 seconds, the problem i have is that the "timer" activates immediately instead of starting when the sensor spots something.

system · June 11, 2023, 1:51pm

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Make millis timer wait until a if statement i true(Need help)

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