This code is designed to continuously blink an LED with Pot1 controlling timeOn and Pot2 controlling timeOff. When the button is pushed, the sequence starts and loops, however once running, the delays in the loop prevent the button from toggling off and keeping the LED low. I know to make this work I need to use millis() so the code can loop freely without interfering with the button, but I'm having great difficulty controlling the single LED's on and off time with 2 Pots using millis(). Any and all help is greatly appreciated! Here's the reference code. It works only every few button pushes... int led = 2; int Button = 3; int pot1 = A4; int pot2 = A5; boolean toggle = false; void setup() { pinMode(led, OUTPUT); pinMode(Button, INPUT_PULLUP); } void loop() { int B = digitalRead(Button); int timeOn = analogRead(pot1); timeOn = map(timeOn, 0, 1023, 50, 500); int timeOff = analogRead(pot2); timeOff = map(timeOff, 0, 1023, 50, 500); if (B == LOW){toggle = !toggle; delay(200);} if (toggle == true){ digitalWrite(led, HIGH); delay(timeOn); digitalWrite(led, LOW); delay(timeOff);} if (toggle == false){digitalWrite(led, LOW);} }

Hello I think the IDE example named BlinkWithOutDelay will help. https://www.arduino.cc/en/pmwiki.php?n=Tutorial/BlinkWithoutDelay#:~:text=Blink%20Without%20Delay.%20Sometimes%20you%20need%20to%20do,pass%2C%20your%20program%20will%20miss%20the%20button%20press.

[image] anon26912280: I know to make this work I need to use millis() so the code can loop freely without interfering with the button, but I'm having great difficulty controlling the single LED's on and off time with 2 Pots using millis(). Start with File->Examples->02.Digital->BlinkWithoutDelay When the LED switches from ON to OFF, take that opportunity to change the 'interval': // if the LED is off turn it on and vice-versa: if (ledState == LOW) { ledState = HIGH; interval = map(analogRead(pot1), 0, 1023, 50, 500); } else { ledState = LOW; interval = map(analogRead(pot2), 0, 1023, 50, 500); } Of course, if you do that without changing anything else you will get an error: "assignment of read-only variable 'interval'". That means "Take the 'const' keyword off of the declaration of 'interval' if you want to be able to change it!"

From all of these suggestions (and more from another thread) I've cracked it. Toggling an LED with ON & OFF interval potentiometers. int timeOn = A3; int timeOff = A7; int Button = 4; int led = 6; boolean toggle = false; unsigned long timeLedChanged = millis(); unsigned long period; boolean ledOn = false; void setup() { pinMode(led, OUTPUT); pinMode(Button, INPUT_PULLUP); digitalWrite(led, LOW); } void loop() { int B = digitalRead(Button); int onVal = analogRead(timeOn); onVal = map(onVal, 0, 1023, 50, 500); int offVal = analogRead(timeOff); offVal = map(offVal, 0, 1023, 50, 500); if (B == LOW){toggle = !toggle; delay(200);} if (toggle== true){ if (millis() - timeLedChanged >= period){ ledOn = !ledOn; timeLedChanged = millis(); digitalWrite(led, ledOn); if (ledOn){ period = (onVal);} else{ period = (offVal);} } } if (toggle == false){ ledOn = false; digitalWrite(led, LOW);} } Thanks for all the help everyone!

If I understand the "intent" of your code correctly the button controls whether the LED is ON (and blinking based on potentiometers) or whether the LED is OFF all of the time. If you want the button to be responsive you will have to remove the delays and use millis().

That's the correct function yes. Each example of millis() I've seen uses variables based on the time between changes. I think my issue is storing 2 lots of data from the pots and having them act upon the LED simultaniously, which I find easiest with delays.

That's a fantastic link, thankyou ToddL1962!

[image] anon26912280: I think my issue is storing 2 lots of data from the pots and having them act upon the LED simultaniously, which I find easiest with delays. You can use a little state machine which will make the code very easy to manage.

@anon26912280 If you want that the LED should bink only once when button is closed and released, then your sketch requires following modification that involes the resetting of the variable state after one pass. (Current sketch of Post-1 will continuously blink LED and it does when button is closed and released only for once.) int LED = 2; int Button = 4; int timeOn = A3; int timeOff = A4; boolean state = false; void setup() { pinMode(LED, OUTPUT); pinMode(Button, INPUT_PULLUP); } void loop() { int B = digitalRead(Button); int onVal = analogRead(timeOn); onVal = map(onVal, 0, 1023, 50, 500); int offVal = analogRead(timeOff); offVal = map(offVal, 0, 1023, 50, 500); if (B == LOW) { state = ! state; //Button closed change state delay(200); } if (state == true) { digitalWrite(LED, HIGH); delay(onVal); digitalWrite(LED, LOW); delay(offVal); state = false; } /* if (state == false) { digitalWrite(LED, LOW); }*/ }

Unless OP wants it to continuously blink until the button turns it off. That was the assumption of OP intent I made.

2 Potentiometers controlling a single LED

Projects Programming

ToddL1962 August 17, 2021, 3:04pm 10

The following tutorials should help you out:

State Change Detection

Using millis() for timing

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2 Potentiometers controlling a single LED

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