Run function A for 2 mins then run function B forever

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1

I have 2 different functions for blinking an LED. When the device books up I want it to run function A for 2 mins and then run function B in a loop forever. What is the simplest way to achieve this?

2

put function a in setup with 2 min delay and b in loop

3 
unsigned long ms;
bool func2;
void setup() {
  func2 = false;
  ms = millis();
}

void loop() {
  if (!func2) {  
    if (millis() - ms <= 1000L*60*2) {
      func1();
    }
    else {
      func2 = true;
    }
  }
  else {   
     func2();
  }
}
4

Danger -- overflowing an int gives undefined behavior:

try:

    if (millis() - ms <= 1000L*60*2) {

Predict the output of:

void setup() {
  Serial.begin(115200);
  if (1000 * 60 * 2 > 10000 ) {
    Serial.print("overflowed signed int greater than 10K");
  }
  if (1000L * 60 * 2 > 10000 ) {
    Serial.print("unsigned int greater than 10K");
  }
}

void loop() {
}

Edit:

Or simpler: Would you expect this to print -11072?

Serial.println(1000 * 60 * 2);
1 Like
5

Thank you!

6

Perfect! Thank you. I don't think you can define func2 as bool and a function though, can you?

7

Yes, you are right, sorry for that

8

simplest way is what i said(i think)

9

It definitely is, but glutio's solution caters better to my use case, since I also want to be able to switch between func1 & func2 via button press, which starts the timer over by setting ms = millis(); and mode = !mode; on button press. I should have indicated that in my post.

10

ok....well...yeah that figures

11

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