CODEWITHSUNDEEP
c++mbed
user5647516
user5647516

Reputation: 1283

how to let a function keep looping outside the main loop until a button is pressed

I have a function, which I want to keep running until a button is pressed (sw2_trig and sw3_trig), which makes it enter one of the modes in the main loop. The problem is that I tried a while loop and a do while loop outside the main loop to achieve this but it is not working, all it does is loop the function and I cannot enter mode 1 or 2 even if I press sw2 or sw3. here is my code.

/*********************************************************************
Intereupt Handlers
********************************************************************/

void sw2_interrupt (void) //adapted from driving_test_2
{
    sw2_trig = 1;
}


void sw3_interrupt (void) //adapted from driving_test_2
{
    sw3_trig = 1;
}

/*******************************************************************************
Functions
*******************************************************************************/
//I want to keep this function running until sw2_trig or sw3_trig is pressed inside the main loop.

void furElise() {
    float notes[] = { e, d, e, d, e, b, D, c, _, a, _, c, e, a, b, _, e, g, b, c, _, e, d, e, d, a, e, a, _, e, e, g, a, e, a};

    for (int i = 0; i < sizeof(notes) / sizeof(float); i++) {
        if (notes[i] == _) {
            spkr = 0.0f;
        }
        else {
            spkr = 0.5f;
            spkr.period(1 / notes[i]);
        }
        wait(0.25f);      
    }

    spkr = 0.0f;
}

*****************************************************************************************
Begin Program
****************************************************************************************/

int main()
{

 sw2_trig = 0;
 sw3_trig = 0;

 sw2_int.mode (PullUp);
 sw2_int.fall (&sw2_interrupt);

 sw3_int.mode (PullUp);
 sw3_int.fall (&sw3_interrupt);

int mode = 0; //Don't show anything

furElise(); // want to keep this running if sw2 or sw3 aren't pressed.



    while (1) {

        spkr = 0.0;
        wait(0.2f); //wait a little 


        switch (mode) {

            case 1:
lm_temp.read();

break();

case 2:

yellowPurple();

break;

    if(sw2_trig) {
        mode = 1;
        sw2_trig = 0;
        shld_lcd.cls();
        }

    if(sw3_trig) {
        mode = 2;
        sw3_trig = 0;
        shld_lcd.cls();
        }        
    }
}

Upvotes: 1

Views: 1473

Answers (1)

Sudipta Kumar Sahoo
Sudipta Kumar Sahoo

Reputation: 1147

You can keep Polling inside furElise() function until the sw2_trig and sw3_trig trigger not equal to 1. Once it is equal to 1, you can break the loop.

Dummy Code

if(sw2_trig == 1 || sw3_trig == 1)
{
   return;
}

So when the interrupt comes, either of these values become 1 in interrupt handler.

Polling is not the best technique, but this is one way you can solve your issue.

Hope this helps.

Upvotes: 5

Related Questions