Running code independently

Using Arduino Programming Questions
1

I have a LDR sensor reading analog value, i have a led, once ldr reads 800 or above it should turn on led and wait for 1 hour and turn it off, Problem here is let led be in whatever state but analog values should print in serial monitor all the time.

2

What have you tried?

3

I'm guessing you use an delay(....); function for the led to stay on? Is that correct?

Incase of that, you could use millis. As an if function for the timing.
https://forum.arduino.cc/index.php?topic=503368.0

while using millis your loop keeps online, and doesn't wait until the time of delay come. So you will be able to keep printing the analog value.

4

int val;
void setup() {
pinMode(D5,OUTPUT);
digitalWrite(D5,LOW);
Serial.begin(9600);
}

void loop() {
val=analogRead(A0);
Serial.println(val);
if(val>800){
digitalWrite(D5,HIGH);
delay(3600000);
}

digitalWrite(D5,LOW);

}

i dont want to stop analogread for 1 hour

5

i dont want to stop analogread for 1 hour

So stop doing this:

delay(3600000);

Delay stops everything from happening while the delay is running. The post linked in reply #2 by Gert-Jan_Snik is the answer. Read it and if you have questions, ask away.

6

AbhayHM:
int val;
void setup() {
pinMode(D5,OUTPUT);
digitalWrite(D5,LOW);
Serial.begin(9600);
}

void loop() {
val=analogRead(A0);
Serial.println(val);
if(val>800){
digitalWrite(D5,HIGH);
delay(3600000);
}

digitalWrite(D5,LOW);

}

i dont want to stop analogread for 1 hour

something like this maybe then:

#define D5 5
const unsigned long WAIT_TIME = 3600000;
unsigned long old_time1, old_time2;
uint16_t val;
uint8_t flag;
void setup() {
  pinMode(D5, OUTPUT);
  digitalWrite(D5, LOW);
  old_time1 = millis();
  old_time2 = old_time1;
  Serial.begin(9600);
  flag = 0;
}

void loop() {
  analogRead(A0);
  val = analogRead(A0);

  if (val > 800 && flag == 0) {
    digitalWrite(D5, HIGH);
    old_time1 = millis();
    flag = 1;
  }
  else if (flag == 1 && millis() - old_time1 > WAIT_TIME) {
    digitalWrite(D5, LOW);
    flag = 0;
  }
  
  if (millis() - old_time2 > 1000) { //serial print every 1000ms
    Serial.println(val);
    old_time2 = millis();
  }
}
7

The functions delay() and delayMicroseconds() block the Arduino until they complete.
Have a look at how millis() is used to manage timing without blocking in Several Things at a Time.

And see Using millis() for timing. A beginners guide if you need more explanation.

...R