How do to Interval timer

Projects Programming
1

Hello,

Im preatty new to this whole arduino coding thing..
I am building terrarium for chameleon which has humidity measurement and control and this is already working just fine. Now I am trying to figure out how to turn on water pump on every 1h for 3 seconds.
(chameleons do not drink from water cup so I need to spray water to leafs for short period which falls down to pump)

I have read and tried few guides, but I just can´t get my head around how to do timer which is re-occurring every X seconds for Y period of time.

Could someone point me to right direction?

2

Have a look at Using millis() for timing. A beginners guide Your requirement is really just BlinkWithoutDelay with different on/off periods

If precise timing is required get a Real Time Clock module

3

Thank you.

Ill look on that again :slight_smile:

I have already ordered RTC module altough precise timing is not needed for this.

4

Sepi12:
Hello,

Im preatty new to this whole arduino coding thing..
I am building terrarium for chameleon which has humidity measurement and control and this is already working just fine. Now I am trying to figure out how to turn on water pump on every 1h for 3 seconds.
(chameleons do not drink from water cup so I need to spray water to leafs for short period which falls down to pump)

I have read and tried few guides, but I just can´t get my head around how to do timer which is re-occurring every X seconds for Y period of time.

Could someone point me to right direction?

The BlinkWithoutDelay sketch that comes with the IDE, is a timer that re-occurs every 2 seconds for 1 second of time. Just change the numbers...

5

Here's an example of BlinkWithoutDelay with different on/off times. The new idea from the standard BWOD is to change the interval each time you switch from on to off and off to on.

const byte ledPin =  LED_BUILTIN;// the number of the LED pin
byte ledState = LOW;             

unsigned long previousMillis = 0;       
unsigned long intervalOn = 1000; //use 3000 for three seconds on         
unsigned long intervalOff= 5000;//use 3600000 for one hour off
unsigned long interval = intervalOff; //start off

void setup() {
  pinMode(ledPin, OUTPUT); 
}

void loop() {
  unsigned long currentMillis = millis();
  
  if (currentMillis - previousMillis >= interval) {
    previousMillis = currentMillis;
    if (ledState == LOW) {
      ledState = HIGH;
      interval = intervalOn;
    } else {
      ledState = LOW;
      interval = intervalOff;
    }
    digitalWrite(ledPin, ledState);
  }
}
1 Like
6

cattledog:
Here's an example of BlinkWithoutDelay with different on/off times. The new idea from the standard BWOD is to change the interval each time you switch from on to off and off to on.

Thank you ! I looked that new BWOD and figured out that it cant work like it. I was too afraid to ask again tho :smiley: