I started a code to control an Arduino Uno with an LED light. all my electrical is fine, but I'm having trouble with the code as I want to have the LED light run when the button is pressed but turn off after 5 seconds even if it is still pressed down. I've been able to get it to turn off after releasing and waiting 5 seconds by using a delay, but that is not the outcome I want. I think the issue might be with the int and having it as a global versus local, but I do not know what else to do. I attached the code if yall could help!!!!! int led = 7; int BUTTON_PIN = 8; int buttonState = 0; int timer; void setup() { pinMode(led, OUTPUT); pinMode (BUTTON_PIN, INPUT); Serial.begin(9600); } void loop() { buttonState = digitalRead(BUTTON_PIN); Serial.println(buttonState); if (buttonState == HIGH){ while(timer<=5000){ digitalWrite(led,HIGH); } }else{ digitalWrite(led,LOW); int timer=0; } }

the led turns on when thelimit switch ocnnects to the circuit and reads voltage

[image] bpall: while(timer<=5000){ digitalWrite(led,HIGH); } how do you think timer will change its value ? study Using millis() for timing. A beginners guide Several things at the same time Flashing multiple LEDs at the same time you might also benefit from studying state machines. Here is a small introduction to the topic: Yet another Finite State Machine introduction

Try this code: int led = 7; int BUTTON_PIN = 8; int buttonState = 0; unsigned long timer = 0; bool turn_On = false; //------------------------------------------------------------ void setup() { pinMode(led, OUTPUT); pinMode (BUTTON_PIN, INPUT); Serial.begin(9600); } //------------------------------------------------------------ void loop() { if (turn_On == false) { if (digitalRead(BUTTON_PIN) == LOW) { timer = millis(); digitalWrite(led, HIGH); turn_On = true; } } if (millis() - timer >= 5000) { digitalWrite(led, LOW); if (digitalRead(BUTTON_PIN) == HIGH) turn_On = false; delay(50); } }

i tried that and it still wont turn the led off while the button is still pressed. I think that is the issue im running into. heres the current code ive been trying. right now the led stays on when pressed and turn off when i go off the button int led = 7; int BUTTON_PIN = 8; int buttonState = 0; unsigned long startMillis; //some global variables available anywhere in the program unsigned long currentMillis; const unsigned long period = 5000; void setup() { pinMode(led, OUTPUT); pinMode (BUTTON_PIN, INPUT); Serial.begin(9600); startMillis = millis(); } void loop() { buttonState = digitalRead(BUTTON_PIN); Serial.println(buttonState); currentMillis = millis(); if (buttonState == HIGH){ if(startMillis - currentMillis>=period){ digitalWrite(led,HIGH); }else{ digitalWrite(led,LOW); } }else{ digitalWrite(led,LOW); startMillis = currentMillis; } }

how did you wire the button? do you have an external pulldown ? also you don't handle bouncing...

the limit switch is connected to port the 5v port and the ground port and connected to the led pathway so it can read the voltage and turn on and off based on that. what do you mean by external pulldown?

[image] bpall: what do you mean by external pulldown? have you read https://docs.arduino.cc/built-in-examples/digital/Button/ it's hard to see what's connected where on the pictures, if you could draw your circuit (just rectangles with used pin names and lines for connectors) and post it here it would be easier

sorry still hard to read loose the breadboard just draw the wires and resistors where they are your button and resistor needs to be wired like this (adjust the pin for the one you are using) [image] The pin from which you read the signal is on the other side of the switch compared to the 5V connection, before the resistor. (if you were to use INPUT_PULLUP it would be easier and there would be no need for an extra resistor)

Setting variable and overriding for a timer in arduino

Projects Programming

J-M-L February 16, 2024, 6:58pm 3

how do you think timer will change its value ?

study

Using millis() for timing. A beginners guide
Several things at the same time
Flashing multiple LEDs at the same time

you might also benefit from studying state machines. Here is a small introduction to the topic: Yet another Finite State Machine introduction

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Setting variable and overriding for a timer in arduino

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