Hi, I'm working on a coaster for new year's that will blink after 20 minutes if the person didn't drink. The problem is, my code can't detect the button constantly, it only sees it when pressed. My code here has the delay shortened to 20 seconds for testing: int ledPin=5; int scale=6; const int buttonPin = 2; int buttonPushCounter = 0; int buttonState = 0; int lastButtonState = 0; void setup() { pinMode(buttonPin, INPUT); pinMode(ledPin, OUTPUT); Serial.begin(9600); } void loop() { buttonState = digitalRead(buttonPin); if (buttonState == HIGH) { delay(20000); digitalWrite(ledPin, HIGH); delay(1000); digitalWrite(ledPin, LOW); delay(1000); digitalWrite(ledPin, HIGH); delay(1000); digitalWrite(ledPin, LOW); digitalWrite(ledPin, HIGH); delay(1000); digitalWrite(ledPin, LOW); delay(1000); Serial.print(buttonState); } else { digitalWrite(ledPin, LOW); Serial.print(buttonState); } }

I finally got it working! here it is, in all it's glory: unsigned long startMillis; unsigned long currentMillis; const unsigned long period = 10000; const int ledPin = 6; int buttonState = 0; const int button = 5; void setup() { Serial.begin(9600); pinMode(ledPin, OUTPUT); startMillis = millis(); pinMode(button, INPUT); } void loop() { buttonState = digitalRead(button); if(buttonState == HIGH){ currentMillis = millis(); if (currentMillis - startMillis >= period) { digitalWrite(ledPin, HIGH); startMillis = currentMillis; } } else { startMillis = currentMillis; Serial.print("off"); digitalWrite(ledPin, LOW); } } Thank you all so much for you help!

First things first. How is your button wired? You are configuring it as INPUT which implies you have a pull-up or pull-down resistor. Your code implies you have a pull-up resistor. If you do, you can eliminate the resistor by configuring the pin as INPUT_PULLUP to use the internal pull-up resistor.

OK this means, you have to detect state-change and you have a sequence of steps This is a classical case for a programming-technique called state-machine a state-machine reduces the number of if-conditions you have to check You will need some time to understand the concept of state-machines the alternative is to add a lot more if-conditions with boolean variables to achieve the same behaviour. Once you have understood the concept of state-machines it becomes very easy the state-machine is initialised to a state "startTimer" if mug is placed on coaster (IO-pin-signal HIGH) // this is even the case on power-up myActualState = startTimer inside state "startTimer" the time-measuring is started previousMillis = currentMillis and the state-variable gets immediately assigned the next statevalue actual State = measureTime in state measureTime you check two things: if 20 minutes are over or not if 20 minutes are over you assign a boolean variable blinkLED = true if mug is taken off the coaster (IO-pin == LOW) if (IO-pin == LOW) actualState = "waitForMugPlacedAgain" blinkLED = false in state "waitForMugPlacedAgain" check if mug is placed back on the coaster if ((IO-pin == HIGH) actualState = startTimer is called everytime if (blinkLED == true) code that makes what the name says best regards Stefan

Has the OP looked into millis()? millis() is a way to count time. unsigned long TimeToBlinky = 1200*(60*1000); unsigned long LastTimeDrink = millis(); loop() { if (millis()-TimeToBlinky >= LastTimeDrink) { Do the LED blinky thingy } if ( tookdrinkSwitch==DrinkTook ) { Stop the LED Blinky LastTimeDrink = millis(); } } millis() and delay do not work well together but by using millis() the CPU is not put to NOP and can respond to the lifting and setting down of the drink glass. Search on this site for things like doing multiple things at the same time and you might look into implementing a state machine for this project. Look to getting rid of those delays.

Thanks a ton, I will try those solutions. I was also wondering if it would work to to do something with a loop like loop() delay(20) if(buttonvalue==HIGH) continue loop else end loop only problem is you need to control duration and be able to end the loop, though maybe you could potentially do that with setup()?

aalso to answer your question it is a button, with the pin on input one one side with ground(in series with a resistor) and 5 volts on the other side if i remember correctly

This is a demo-code that shows the principle of a state-machine. This example has not exact your functionality. After looking at this example ask as many questions as you like. I'm interested in improving the explanation to become easier to understand. [image] A Demo-Code explaining the switch-case state-machine and how to do things (almost) in parallel Tutorials Hi everybody, if you look at the end of this first posting you see a list of links that show where this tutorial was used as a link. Go through this list to find additional information on how to apply this code This democode requires only the pure microcontroller without any hardware. You just open the serial monitor to watch the behaviour of the code. From time to time I enjoy writing demo-codes that want to explain programming-functionalities. There are a lot of different approachs to expl… best regards Stefan

[image] gandalf12: delay(20) I do not use delay.

I tried your way, here is what i have so far unsigned long lastTimeDrink = millis(); const int mugSensor = 5; const int timeToDrinkBoi = 6; void setup() { pinMode(5, INPUT); pinMode(6, OUTPUT); } void loop() { if(millis()-120000 >= lastTimeDrink){ digitalWrite(timeToDrinkBoi, HIGH); delay(1000); digitalWrite(timeToDrinkBoi, LOW); delay(1000); digitalWrite(timeToDrinkBoi, HIGH); delay(1000); digitalWrite(timeToDrinkBoi, LOW); delay(1000); digitalWrite(timeToDrinkBoi, HIGH); delay(1000); digitalWrite(timeToDrinkBoi, LOW); } } also sorry about delay fuction i do not really know work around in this code

i tried the code and for some reason it starts to blink right away. any reason why? great thanks

You do the same as in this piece of code currentMillis = millis(); if (currentMillis - previousMillis >= interval) { previousMillis = currentMillis; //code to toggle the LED but with its own variable previousMillisLED and its own variable intervalLED You should put the blink-code into its own function best regards Stefan

Constant button reading

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StefanL38 December 21, 2021, 9:02pm 17

This is a demo-code that shows the principle of a state-machine.

This example has not exact your functionality. After looking at this example ask as many questions as you like. I'm interested in improving the explanation to become easier to understand.

best regards Stefan

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Constant button reading

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