Hey All, I have a code where i want my arduino nano to look for a closed circuit on pins d2-d11, if any of the pins are closed for more than 5 seconds i want it to sound an alarm (or turn on an LED) connected to pin d12. ive got the turn on part working, but i want the led to turn off immediately when circuit open again. currently there seems to be a 5 second delay for the led to also turn off. Ive tried to get chat GPT to write it and fix it but went round in circles. it wouldnt be my physical setup would it? i have pin 12 going to a resistor into the led then to ground, for the switches i just have going from ground to any of the d2-d11 pins. ? heres the code: // Define the pins to monitor const int startPin = 2; // Start pin (D2) const int endPin = 11; // End pin (D11) // Define the LED pin const int ledPin = 12; // D12 pin on Arduino Nano void setup() { // Initialize the LED pin as an output pinMode(ledPin, OUTPUT); // Initialize the digital pins as inputs with pull-up resistors for (int pin = startPin; pin <= endPin; ++pin) { pinMode(pin, INPUT_PULLUP); } } void loop() { // Flag to track if any pin forms a circuit for more than 5 seconds bool circuitDetected = false; // Loop through each pin to check if it's connected to ground for (int pin = startPin; pin <= endPin; ++pin) { // If the pin is connected to ground (LOW), set the flag and break the loop if (digitalRead(pin) == LOW) { // Wait for 5 seconds to ensure the circuit is continuously closed delay(5000); if (digitalRead(pin) == LOW) { circuitDetected = true; break; } } } // If a circuit is detected, turn on the LED if (circuitDetected) { digitalWrite(ledPin, HIGH); } else { // If no circuit is detected, turn off the LED digitalWrite(ledPin, LOW); delay(10); // Ensure the LED turns off immediately } }

[image] silmslice: it wouldnt be my physical setup would it? i have pin 12 going to a resistor into the led then to ground, for the switches i just have going from ground to any of the d2-d11 pins. ? No, that's all ok. It's your code. Specifically it's that delay(5000). You need to be using millis() for the timing.

thank you, i tried taking small steps and everything worked till adding the 5 second timer. will do some learning and try another night, my attempt tonight came back with a code error so will read through this thread and try getting it working. [image] Using millis() for timing. A beginners guide Introductory Tutorials Part 1 It is not usually long before new Arduino users discover that although the delay() function is easy to use it has side effects, the main one of which is that its stops all activity on the Arduino until the delay is finished (not quite true, I know, but that is usually how the problem presents itself). When this occurs the new user is usually directed to the BlinkWithoutDelay example sketch (BWoD) and/or the excellent thread entitled Several things at the same time. Several things at the…

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[image] silmslice: there seems to be a 5 second delay for the led to also turn off. Consider this: What happens when you hold a button down for longer than 5 seconds, say 5.1 seconds?

[image] silmslice: i want my arduino nano to look for a closed circuit on pins d2-d11, if any of the pins are closed for more than 5 seconds i want it to sound an alarm... i want the led to turn off immediately when circuit open again. You don't actually need 10 pins for that, you could connect all 10 buttons to the same pin.

Here's my attempt, if you want to see it: // Define the pins to monitor const int startPin = 2; // Start pin (D2) const int endPin = 11; // End pin (D11) // Define the LED pin const int ledPin = 12; // D12 pin on Arduino Nano void setup() { // Initialize the LED pin as an output pinMode(ledPin, OUTPUT); // Initialize the digital pins as inputs with pull-up resistors for (int pin = startPin; pin <= endPin; ++pin) { pinMode(pin, INPUT_PULLUP); } } void loop() { // Flag to track if any pin forms a circuit for more than 5 seconds bool circuitDetected = false; static bool timerStarted = false; static unsigned long detectionTime; // Loop through each pin to check if it's connected to ground for (int pin = startPin; pin = 5000) { digitalWrite(ledPin, HIGH); } } else { // Start a 5 second timer detectionTime = millis(); timerStarted = true; } } else { // If no circuit is detected, turn off the LED digitalWrite(ledPin, LOW); timerStarted = false; } }

amazing, thank you this works perfect! Looking forward to exploring a few more projects.

The reason I wanted 10 pins, was because i have 10 contactors activated by 10 photoelectric sensors and was worried about inadvertently linking them together.

[image] silmslice: Ive tried to get chat GPT to write it It would be fun to take this up with chatGPT. Who knows, maybe it could solve the problem. One quick change my HI came up with, which is worth as much, is to condition the five second delay on its being the first time you make the LED go on, viz: void loop() { static bool circuitDetected; int pin: for (pin = startPin; pin endPin) circuitDetected = false; } // rest of loop unchanged I can't test this at the moment. Show chatGPT both versions of the complete loop()and ask it to explain it to you. a7

[image] alto777: I can't test this at the moment. It got tested it and a mistake or two fixed, thank her very much... This is the complete loop. I commented out the delay(10) for the nonsense it made to me. void loop() { static bool circuitDetected; int pin; for (pin = startPin; pin endPin) circuitDetected = false; if (circuitDetected) { digitalWrite(ledPin, HIGH); } else { digitalWrite(ledPin, LOW); // ??? delay(10); // Ensure the LED turns off immediately } } HTH and sry, shoulda waited until I coulda tested (and fized) it myself. a7

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silmslice March 24, 2024, 10:14am 3

thank you, i tried taking small steps and everything worked till adding the 5 second timer.

will do some learning and try another night, my attempt tonight came back with a code error so will read through this thread and try getting it working.

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