8051/C: Enter blink-mode when button is pressed, exit when pressed again or after 30 seconds

Question

So I have an LED and a button.

When the button is pressed, the LED should start blinking. It either stops blinking after 30s or if the button is pressed again.

I have implemented the entering of the blinking state and leaving it after 30s, but I don't know how to leave it at any time with the push of the button. Any help appreciated!

while(1)
{

    if(button is pressed)
    {
         for(i=0, i<60, i++)
         {
           toggleLED();
           wait(500ms);
         }
    }
}

Answer 1

You are almost there: you need to add watching the button in the intervals between blinking the LED:

if(button is pressed)
{
     for(i=0, i<60, i++)
     {
       toggleLED();
       wait(500ms);
       if (button is pressed)
       {
           turnLedOff();
           break;
       }
     }
}